Publications

88 entries « ‹ 1 of 2 › »

2023
	Julia Ericson, Torkel Klingberg A dual-process model for cognitive training Journal Article Science of Learning, 8 (1), pp. 12, 2023. Abstract \| Links @article{Ericson2023, title = {A dual-process model for cognitive training}, author = {Julia Ericson, Torkel Klingberg}, url = {https://www.nature.com/articles/s41539-023-00161-2}, doi = {https://doi.org/10.1038/s41539-023-00161-2}, year = {2023}, date = {2023-05-06}, journal = {Science of Learning}, volume = {8}, number = {1}, pages = {12}, abstract = {A key goal in cognitive training research is understanding whether cognitive training enhances general cognitive capacity or provides only task-specific improvements. Here, we developed a quantitative model for describing the temporal dynamics of these two processes. We analyzed data from 1300 children enrolled in an 8 week working memory training program that included 5 transfer test sessions. Factor analyses suggested two separate processes: an early task-specific improvement, accounting for 44% of the total increase, and a slower capacity improvement. A hidden Markov model was then applied to individual training data, revealing that the task-specific improvement plateaued on the third day of training on average. Thus, training is not only task specific or transferable but a combination of the two. The models provide methods for quantifying and separating these processes, which is crucial for studying the effects of cognitive training and relating these effects to neural correlates.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close A key goal in cognitive training research is understanding whether cognitive training enhances general cognitive capacity or provides only task-specific improvements. Here, we developed a quantitative model for describing the temporal dynamics of these two processes. We analyzed data from 1300 children enrolled in an 8 week working memory training program that included 5 transfer test sessions. Factor analyses suggested two separate processes: an early task-specific improvement, accounting for 44% of the total increase, and a slower capacity improvement. A hidden Markov model was then applied to individual training data, revealing that the task-specific improvement plateaued on the third day of training on average. Thus, training is not only task specific or transferable but a combination of the two. The models provide methods for quantifying and separating these processes, which is crucial for studying the effects of cognitive training and relating these effects to neural correlates. Close https://www.nature.com/articles/s41539-023-00161-2 doi:https://doi.org/10.1038/s41539-023-00161-2 Close
	Samson Nivins, Torkel Klingberg Effects of prenatal exposure to maternal diabetes mellitus on deep grey matter structures and attention deficit hyperactivity disorder symptoms in children Journal Article Acta paediatrica, 2023. Abstract \| Links @article{Nivins2023b, title = {Effects of prenatal exposure to maternal diabetes mellitus on deep grey matter structures and attention deficit hyperactivity disorder symptoms in children}, author = {Samson Nivins, Torkel Klingberg}, url = {https://onlinelibrary.wiley.com/doi/full/10.1111/apa.16756}, doi = {https://doi.org/10.1111/apa.16756}, year = {2023}, date = {2023-03-23}, journal = {Acta paediatrica}, abstract = {Aim: The neuronal mechanism linking the association between maternal diabetes mellitus (DM) and risk of attention deficit hyperactivity disorder (ADHD) symptoms and working memory deficits in children was investigated. Methods: A total of 6291 children (52% boys) born beyond 28 weeks of gestation were included and underwent brain magnetic resonance imaging scans at 9–10 years. Subcortical brain volumes were estimated from the T1-weighted images. ADHD symptoms were assessed using factorial analysis of the Child Behaviour Checklist completed by parents/caregivers. Working memory performance was assessed with the NIH Toolbox. Results: Compared to unexposed children, those exposed to DM (n = 422) had smaller (β = −0.15, p = 0.001) volumes of pooled deep grey matter (GM). Regional analysis revealed smaller volumes of the caudate nucleus, putamen, thalamus and cerebellum but not of hippocampus. They also had altered cortico-striatal white matter projection tracts. DM was not associated with working memory deficits or inattention, but with increased hyperactivity/impulsivity and Sluggish Cognitive Tempo symptoms in boys. This hyperactivity/impulsivity symptom in boys was partially mediated by smaller deep GM volume. Conclusion: Exposure to DM during pregnancy leads to altered deep GM development during late childhood in their offspring. This contributed to an increased risk of hyperactivity/impulsivity symptoms in boys.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Aim: The neuronal mechanism linking the association between maternal diabetes mellitus (DM) and risk of attention deficit hyperactivity disorder (ADHD) symptoms and working memory deficits in children was investigated. Methods: A total of 6291 children (52% boys) born beyond 28 weeks of gestation were included and underwent brain magnetic resonance imaging scans at 9–10 years. Subcortical brain volumes were estimated from the T1-weighted images. ADHD symptoms were assessed using factorial analysis of the Child Behaviour Checklist completed by parents/caregivers. Working memory performance was assessed with the NIH Toolbox. Results: Compared to unexposed children, those exposed to DM (n = 422) had smaller (β = −0.15, p = 0.001) volumes of pooled deep grey matter (GM). Regional analysis revealed smaller volumes of the caudate nucleus, putamen, thalamus and cerebellum but not of hippocampus. They also had altered cortico-striatal white matter projection tracts. DM was not associated with working memory deficits or inattention, but with increased hyperactivity/impulsivity and Sluggish Cognitive Tempo symptoms in boys. This hyperactivity/impulsivity symptom in boys was partially mediated by smaller deep GM volume. Conclusion: Exposure to DM during pregnancy leads to altered deep GM development during late childhood in their offspring. This contributed to an increased risk of hyperactivity/impulsivity symptoms in boys. Close https://onlinelibrary.wiley.com/doi/full/10.1111/apa.16756 doi:https://doi.org/10.1111/apa.16756 Close
2022
	Nicholas Judd, Bruno Sauce, Torkel Klingberg Schooling substantially improves intelligence, but neither lessens nor widens the impacts of socioeconomics and genetics Journal Article npj Science of Learning, 7 (1), pp. 33, 2022. Abstract \| Links @article{Judd2022, title = {Schooling substantially improves intelligence, but neither lessens nor widens the impacts of socioeconomics and genetics}, author = {Nicholas Judd, Bruno Sauce, Torkel Klingberg}, url = {https://www.nature.com/articles/s41539-022-00148-5}, doi = {https://doi.org/10.1038/s41539-022-00148-5}, year = {2022}, date = {2022-12-15}, journal = {npj Science of Learning}, volume = {7}, number = {1}, pages = {33}, abstract = {Schooling, socioeconomic status (SES), and genetics all impact intelligence. However, it is unclear to what extent their contributions are unique and if they interact. Here we used a multi-trait polygenic score for cognition (cogPGS) with a quasi-experimental regression discontinuity design to isolate how months of schooling relate to intelligence in 6567 children (aged 9–11). We found large, independent effects of schooling (β ~ 0.15), cogPGS (β ~ 0.10), and SES (β ~ 0.20) on working memory, crystallized (cIQ), and fluid intelligence (fIQ). Notably, two years of schooling had a larger effect on intelligence than the lifetime consequences, since birth, of SES or cogPGS-based inequalities. However, schooling showed no interaction with cogPGS or SES for the three intelligence domains tested. While schooling had strong main effects on intelligence, it did not lessen, nor widen the impact of these preexisting SES or genetic factors.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Schooling, socioeconomic status (SES), and genetics all impact intelligence. However, it is unclear to what extent their contributions are unique and if they interact. Here we used a multi-trait polygenic score for cognition (cogPGS) with a quasi-experimental regression discontinuity design to isolate how months of schooling relate to intelligence in 6567 children (aged 9–11). We found large, independent effects of schooling (β ~ 0.15), cogPGS (β ~ 0.10), and SES (β ~ 0.20) on working memory, crystallized (cIQ), and fluid intelligence (fIQ). Notably, two years of schooling had a larger effect on intelligence than the lifetime consequences, since birth, of SES or cogPGS-based inequalities. However, schooling showed no interaction with cogPGS or SES for the three intelligence domains tested. While schooling had strong main effects on intelligence, it did not lessen, nor widen the impact of these preexisting SES or genetic factors. Close https://www.nature.com/articles/s41539-022-00148-5 doi:https://doi.org/10.1038/s41539-022-00148-5 Close
	Da-Wei Zhang, Alexandros Moraidis, Torkel Klingberg Individually tuned theta HD-tACS improves spatial performance Journal Article Brain Stimulation, 15 (6), pp. 1439-1447, 2022. Abstract \| Links @article{Zhang2022, title = {Individually tuned theta HD-tACS improves spatial performance}, author = {Da-Wei Zhang, Alexandros Moraidis, Torkel Klingberg}, url = {https://www.sciencedirect.com/science/article/pii/S1935861X22002327}, doi = {https://doi.org/10.1016/j.brs.2022.10.009}, year = {2022}, date = {2022-11-01}, journal = {Brain Stimulation}, volume = {15}, number = {6}, pages = {1439-1447}, abstract = {Background Using transcranial alternating current stimulation (tACS) to improve visuospatial working memory (vsWM) has received considerable attention over the past few years. However, fundamental issues remain, such as the optimal frequency, the generality of behavioral effects, and the anatomical specificity of stimulation. Objectives Here we examined the effects of two theory-driven tACS protocols for improving vsWM on behavioral and electroencephalogram (EEG) measures. Methods Twenty adults each completed 3 HD-tACS conditions (Tuned, Slow, and Sham) on two separate days. The Tuned condition refers to a situation in which the frequency of tACS is tuned to individual theta peak measured during a vsWM task. By contrast, the frequency was fixed to 4 Hz in the Slow condition. A high-definition tACS was deployed to target smaller frontal and parietal regions for increasing their phase-locking values. During each tACS condition, participants performed vsWM, mental rotation (MR), and arithmetic tasks. Resting-state EEG (rs-EEG) was recorded before and after each condition. Results Compared with Sham, Tuned but not Slow improved both vsWM and MR but not arithmetics. The rs-EEG recording showed an increased fronto-parietal synchrony for Tuned, and this increase in synchronicity was correlated with the behavioral improvement. A follow-up study showed no behavioral improvement in Tuned with an anti-phase setting. Conclusion We provide the first evidence that simulating right fronto-parietal network with the tuned frequency increases the interregional synchronicity and improves performance on two spatial tasks. The results provide insight into the structure of spatial abilities as well as suggestions for stimulating the fronto-parietal network.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Background Using transcranial alternating current stimulation (tACS) to improve visuospatial working memory (vsWM) has received considerable attention over the past few years. However, fundamental issues remain, such as the optimal frequency, the generality of behavioral effects, and the anatomical specificity of stimulation. Objectives Here we examined the effects of two theory-driven tACS protocols for improving vsWM on behavioral and electroencephalogram (EEG) measures. Methods Twenty adults each completed 3 HD-tACS conditions (Tuned, Slow, and Sham) on two separate days. The Tuned condition refers to a situation in which the frequency of tACS is tuned to individual theta peak measured during a vsWM task. By contrast, the frequency was fixed to 4 Hz in the Slow condition. A high-definition tACS was deployed to target smaller frontal and parietal regions for increasing their phase-locking values. During each tACS condition, participants performed vsWM, mental rotation (MR), and arithmetic tasks. Resting-state EEG (rs-EEG) was recorded before and after each condition. Results Compared with Sham, Tuned but not Slow improved both vsWM and MR but not arithmetics. The rs-EEG recording showed an increased fronto-parietal synchrony for Tuned, and this increase in synchronicity was correlated with the behavioral improvement. A follow-up study showed no behavioral improvement in Tuned with an anti-phase setting. Conclusion We provide the first evidence that simulating right fronto-parietal network with the tuned frequency increases the interregional synchronicity and improves performance on two spatial tasks. The results provide insight into the structure of spatial abilities as well as suggestions for stimulating the fronto-parietal network. Close https://www.sciencedirect.com/science/article/pii/S1935861X22002327 doi:https://doi.org/10.1016/j.brs.2022.10.009 Close
	Da-Wei Zhang, Alexandros Moraidis, Torkel Klingberg Individually tuned theta HD-tACS improves spatial performance Journal Article Brain Stimulation, 15 (6), pp. 1439-1447, 2022. Abstract \| Links @article{Zhang2022b, title = {Individually tuned theta HD-tACS improves spatial performance}, author = {Da-Wei Zhang, Alexandros Moraidis, Torkel Klingberg}, url = {https://www.sciencedirect.com/science/article/pii/S1935861X22002327}, doi = {https://doi.org/10.1016/j.brs.2022.10.009}, year = {2022}, date = {2022-11-01}, journal = {Brain Stimulation}, volume = {15}, number = {6}, pages = {1439-1447}, abstract = {Background Using transcranial alternating current stimulation (tACS) to improve visuospatial working memory (vsWM) has received considerable attention over the past few years. However, fundamental issues remain, such as the optimal frequency, the generality of behavioral effects, and the anatomical specificity of stimulation. Objectives Here we examined the effects of two theory-driven tACS protocols for improving vsWM on behavioral and electroencephalogram (EEG) measures. Methods Twenty adults each completed 3 HD-tACS conditions (Tuned, Slow, and Sham) on two separate days. The Tuned condition refers to a situation in which the frequency of tACS is tuned to individual theta peak measured during a vsWM task. By contrast, the frequency was fixed to 4 Hz in the Slow condition. A high-definition tACS was deployed to target smaller frontal and parietal regions for increasing their phase-locking values. During each tACS condition, participants performed vsWM, mental rotation (MR), and arithmetic tasks. Resting-state EEG (rs-EEG) was recorded before and after each condition. Results Compared with Sham, Tuned but not Slow improved both vsWM and MR but not arithmetics. The rs-EEG recording showed an increased fronto-parietal synchrony for Tuned, and this increase in synchronicity was correlated with the behavioral improvement. A follow-up study showed no behavioral improvement in Tuned with an anti-phase setting. Conclusion We provide the first evidence that simulating right fronto-parietal network with the tuned frequency increases the interregional synchronicity and improves performance on two spatial tasks. The results provide insight into the structure of spatial abilities as well as suggestions for stimulating the fronto-parietal network.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Background Using transcranial alternating current stimulation (tACS) to improve visuospatial working memory (vsWM) has received considerable attention over the past few years. However, fundamental issues remain, such as the optimal frequency, the generality of behavioral effects, and the anatomical specificity of stimulation. Objectives Here we examined the effects of two theory-driven tACS protocols for improving vsWM on behavioral and electroencephalogram (EEG) measures. Methods Twenty adults each completed 3 HD-tACS conditions (Tuned, Slow, and Sham) on two separate days. The Tuned condition refers to a situation in which the frequency of tACS is tuned to individual theta peak measured during a vsWM task. By contrast, the frequency was fixed to 4 Hz in the Slow condition. A high-definition tACS was deployed to target smaller frontal and parietal regions for increasing their phase-locking values. During each tACS condition, participants performed vsWM, mental rotation (MR), and arithmetic tasks. Resting-state EEG (rs-EEG) was recorded before and after each condition. Results Compared with Sham, Tuned but not Slow improved both vsWM and MR but not arithmetics. The rs-EEG recording showed an increased fronto-parietal synchrony for Tuned, and this increase in synchronicity was correlated with the behavioral improvement. A follow-up study showed no behavioral improvement in Tuned with an anti-phase setting. Conclusion We provide the first evidence that simulating right fronto-parietal network with the tuned frequency increases the interregional synchronicity and improves performance on two spatial tasks. The results provide insight into the structure of spatial abilities as well as suggestions for stimulating the fronto-parietal network. Close https://www.sciencedirect.com/science/article/pii/S1935861X22002327 doi:https://doi.org/10.1016/j.brs.2022.10.009 Close
	Richard Scruggs, Jalal Nouri, Torkel Klingberg Using Knowledge Tracing to Predict Students’ Performance in Cognitive Training and Math Proceeding Springer International Publishing, 2022. Abstract \| Links @proceedings{Scruggs2022, title = {Using Knowledge Tracing to Predict Students’ Performance in Cognitive Training and Math}, author = {Richard Scruggs, Jalal Nouri, Torkel Klingberg}, url = {https://link.springer.com/chapter/10.1007/978-3-031-11647-6_81}, doi = {https://doi.org/10.1007/978-3-031-11647-6_81}, year = {2022}, date = {2022-07-06}, booktitle = {Artificial Intelligence in Education. Posters and Late Breaking Results, Workshops and Tutorials, Industry and Innovation Tracks, Practitioners’ and Doctoral Consortium: 23rd International Conference}, pages = {410-413}, publisher = {Springer International Publishing}, abstract = {Cognitive training aims to improve skills such as working memory capacity and spatial ability, which have been linked to math skills. In this study, we fit Deep Knowledge Tracing with Transformers (DKTT), Dynamic Key-Value Memory Networks (DKVMN), and Knowledge Tracing Machines (KTM) to a large dataset from a cognitive training system. DKVMN achieved the highest AUC (0.739) of the algorithms. To explore connections between math skills and cognitive skills, the data was split into cognitive and math items. DKVMN’s AUC on the math items was higher (0.745) than on the cognitive (0.706). Notably, the split model AUCs did not differ from skill-level AUCs produced by a model trained on the entire dataset, suggesting that math performance did not improve DKVMN’s cognitive predictions and vice versa.}, keywords = {}, pubstate = {published}, tppubtype = {proceedings} } Close Cognitive training aims to improve skills such as working memory capacity and spatial ability, which have been linked to math skills. In this study, we fit Deep Knowledge Tracing with Transformers (DKTT), Dynamic Key-Value Memory Networks (DKVMN), and Knowledge Tracing Machines (KTM) to a large dataset from a cognitive training system. DKVMN achieved the highest AUC (0.739) of the algorithms. To explore connections between math skills and cognitive skills, the data was split into cognitive and math items. DKVMN’s AUC on the math items was higher (0.745) than on the cognitive (0.706). Notably, the split model AUCs did not differ from skill-level AUCs produced by a model trained on the entire dataset, suggesting that math performance did not improve DKVMN’s cognitive predictions and vice versa. Close https://link.springer.com/chapter/10.1007/978-3-031-11647-6_81 doi:https://doi.org/10.1007/978-3-031-11647-6_81 Close
	Samson Nivins, Bruno Sauce, Magnus Liebherr, Nicholas Judd, Torkel Klingberg The Long-Term Impact of Digital Media on Brain Development in Children Journal Article medRxiv, 2022. Links @article{Nivins2022b, title = {The Long-Term Impact of Digital Media on Brain Development in Children}, author = {Samson Nivins, Bruno Sauce, Magnus Liebherr, Nicholas Judd, Torkel Klingberg}, url = {https://www.medrxiv.org/content/10.1101/2022.07.01.22277142v2}, doi = {https://doi.org/10.1101/2022.07.01.22277142}, year = {2022}, date = {2022-07-05}, journal = {medRxiv}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close https://www.medrxiv.org/content/10.1101/2022.07.01.22277142v2 doi:https://doi.org/10.1101/2022.07.01.22277142 Close
	Bruno Sauce, Magnus Liebherr, Nicholas Judd, Torkel Klingberg The impact of digital media on children’s intelligence while controlling for genetic differences in cognition and socioeconomic background Journal Article Scientific reports, 12 (1), pp. 7720, 2022. Abstract \| Links @article{Sauce2022, title = {The impact of digital media on children’s intelligence while controlling for genetic differences in cognition and socioeconomic background}, author = {Bruno Sauce, Magnus Liebherr, Nicholas Judd, Torkel Klingberg}, url = {https://www.nature.com/articles/s41598-022-11341-2}, doi = {https://doi.org/10.1038/s41598-022-11341-2}, year = {2022}, date = {2022-05-11}, journal = {Scientific reports}, volume = {12}, number = {1}, pages = {7720}, abstract = {Digital media defines modern childhood, but its cognitive effects are unclear and hotly debated. We believe that studies with genetic data could clarify causal claims and correct for the typically unaccounted role of genetic predispositions. Here, we estimated the impact of different types of screen time (watching, socializing, or gaming) on children’s intelligence while controlling for the confounding effects of genetic differences in cognition and socioeconomic status. We analyzed 9855 children from the USA who were part of the ABCD dataset with measures of intelligence at baseline (ages 9–10) and after two years. At baseline, time watching (r = − 0.12) and socializing (r = − 0.10) were negatively correlated with intelligence, while gaming did not correlate. After two years, gaming positively impacted intelligence (standardized β = + 0.17), but socializing had no effect. This is consistent with cognitive benefits documented in experimental studies on video gaming. Unexpectedly, watching videos also benefited intelligence (standardized β = + 0.12), contrary to prior research on the effect of watching TV. Although, in a posthoc analysis, this was not significant if parental education (instead of SES) was controlled for. Broadly, our results are in line with research on the malleability of cognitive abilities from environmental factors, such as cognitive training and the Flynn effect.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Digital media defines modern childhood, but its cognitive effects are unclear and hotly debated. We believe that studies with genetic data could clarify causal claims and correct for the typically unaccounted role of genetic predispositions. Here, we estimated the impact of different types of screen time (watching, socializing, or gaming) on children’s intelligence while controlling for the confounding effects of genetic differences in cognition and socioeconomic status. We analyzed 9855 children from the USA who were part of the ABCD dataset with measures of intelligence at baseline (ages 9–10) and after two years. At baseline, time watching (r = − 0.12) and socializing (r = − 0.10) were negatively correlated with intelligence, while gaming did not correlate. After two years, gaming positively impacted intelligence (standardized β = + 0.17), but socializing had no effect. This is consistent with cognitive benefits documented in experimental studies on video gaming. Unexpectedly, watching videos also benefited intelligence (standardized β = + 0.12), contrary to prior research on the effect of watching TV. Although, in a posthoc analysis, this was not significant if parental education (instead of SES) was controlled for. Broadly, our results are in line with research on the malleability of cognitive abilities from environmental factors, such as cognitive training and the Flynn effect. Close https://www.nature.com/articles/s41598-022-11341-2 doi:https://doi.org/10.1038/s41598-022-11341-2 Close
	Torkel Klingberg, Nicholas Judd, Bruno Sauce Assessing the impact of environmental factors on the adolescent brain: the importance of regional analyses and genetic controls Journal Article World Psychiatry, 21 (1), pp. 146, 2022. Links @article{Klingberg2022, title = {Assessing the impact of environmental factors on the adolescent brain: the importance of regional analyses and genetic controls}, author = {Torkel Klingberg, Nicholas Judd, Bruno Sauce}, url = {https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8751551/}, doi = {10.1002/wps.20934}, year = {2022}, date = {2022-01-11}, journal = {World Psychiatry}, volume = {21}, number = {1}, pages = {146}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8751551/ doi:10.1002/wps.20934 Close
	Samson Nivins, Bruno Sauce, Magnus Liebherr, Nicholas Judd, Torkel Klingberg Digital media does not harm (nor benefit) brain development in children Journal Article medRxiv, 2022. Abstract \| Links @article{Nivins2022, title = {Digital media does not harm (nor benefit) brain development in children}, author = {Samson Nivins, Bruno Sauce, Magnus Liebherr, Nicholas Judd, Torkel Klingberg}, url = {https://www.medrxiv.org/content/10.1101/2022.07.01.22277142v1?%253fcollection=}, doi = {https://doi.org/10.1101/2022.07.01.22277142}, year = {2022}, date = {2022-01-01}, journal = {medRxiv}, abstract = {Importance: Digital media takes an increasingly large part of children’s time, but the effect on brain development is unclear. Objective: To investigate the effects of digital media (watching television and videos, using social media, or playing video games respectively) on the development of the cortex, striatum, and cerebellum over two years. Design, setting, and participants: A prospective, multicenter, longitudinal study of children from the Adolescent Brain and Cognitive Development Study, recruited between 2016-2018. Children underwent magnetic resonance imaging scan at two different time points and completed the Youth Screen Time Survey at first timepoint, answering questions about digital media use. The analysis controlled for differences in socioeconomic status (SES) and polygenic scores for educational attainment. Exposure: Digital media use. Main outcome measures: The primary outcome measure was the changes in the global cortical surface area. Results: 6492 children (age in months, mean [SD] = 118.6 [7.2], i.e., 9.9 years were included at the baseline. Of these, 4502 children (age in months = 142.6 [7.6], i.e., 11.9 years were included at the two years follow-up. The average time spent by children on screen time was 2.2h/day for watching television and videos, 0.4h/day for using social media, and 0.9h/day for playing video games. Over the two-year observation period, the average cortical surface area increased by approximately 2%, reflecting normal cortical development. The amount of time spent playing video games was weakly but positively correlated to change in global cortical surface area (standardised beta, β = 0.03; 95% CI [0.001 – 0.06]; P=.06). No global or regional effect on brain development was observed for a time watching television and videos or using social media. However, the regional analysis showed that playing video games was associated with a larger increase in the volume of the cerebellum (β = 0.01 [0.001 – 0.02]; P=.02). Conclusions and Relevance: This study does not suggest that digital media use in children harms brain development in mid-childhood and within a window of two years, but a longer follow-up is necessary. Question: Does the use of digital media affect brain development in children aged 9-10 years of age? Findings: In this two-year longitudinal study of 4502 children, we found no effect of playing video games, watching television, or using social media on the development of cortical surface area. playing video games was associated with a larger increase in the volume of cerebellum. Meaning: This study does not indicate that the use of digital media harms brain development.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Importance: Digital media takes an increasingly large part of children’s time, but the effect on brain development is unclear. Objective: To investigate the effects of digital media (watching television and videos, using social media, or playing video games respectively) on the development of the cortex, striatum, and cerebellum over two years. Design, setting, and participants: A prospective, multicenter, longitudinal study of children from the Adolescent Brain and Cognitive Development Study, recruited between 2016-2018. Children underwent magnetic resonance imaging scan at two different time points and completed the Youth Screen Time Survey at first timepoint, answering questions about digital media use. The analysis controlled for differences in socioeconomic status (SES) and polygenic scores for educational attainment. Exposure: Digital media use. Main outcome measures: The primary outcome measure was the changes in the global cortical surface area. Results: 6492 children (age in months, mean [SD] = 118.6 [7.2], i.e., 9.9 years were included at the baseline. Of these, 4502 children (age in months = 142.6 [7.6], i.e., 11.9 years were included at the two years follow-up. The average time spent by children on screen time was 2.2h/day for watching television and videos, 0.4h/day for using social media, and 0.9h/day for playing video games. Over the two-year observation period, the average cortical surface area increased by approximately 2%, reflecting normal cortical development. The amount of time spent playing video games was weakly but positively correlated to change in global cortical surface area (standardised beta, β = 0.03; 95% CI [0.001 – 0.06]; P=.06). No global or regional effect on brain development was observed for a time watching television and videos or using social media. However, the regional analysis showed that playing video games was associated with a larger increase in the volume of the cerebellum (β = 0.01 [0.001 – 0.02]; P=.02). Conclusions and Relevance: This study does not suggest that digital media use in children harms brain development in mid-childhood and within a window of two years, but a longer follow-up is necessary. Question: Does the use of digital media affect brain development in children aged 9-10 years of age? Findings: In this two-year longitudinal study of 4502 children, we found no effect of playing video games, watching television, or using social media on the development of cortical surface area. playing video games was associated with a larger increase in the volume of cerebellum. Meaning: This study does not indicate that the use of digital media harms brain development. Close https://www.medrxiv.org/content/10.1101/2022.07.01.22277142v1?%253fcollection= doi:https://doi.org/10.1101/2022.07.01.22277142 Close
2021
	Nicholas Judd, Bruno Sauce, Torkel Klingberg The malleability of intelligence: the effects of schooling, genetic factors, socioeconomic status, and their interplay in children. Journal Article PsyArXiv, 2021. Links @article{judd2021malleabilityb, title = {The malleability of intelligence: the effects of schooling, genetic factors, socioeconomic status, and their interplay in children.}, author = {Nicholas Judd and Bruno Sauce and Torkel Klingberg}, url = {https://psyarxiv.com/96pj4/}, year = {2021}, date = {2021-09-23}, journal = {PsyArXiv}, publisher = {PsyArXiv}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close https://psyarxiv.com/96pj4/ Close
	Da-Wei Zhang, Anna Zaphf, Torkel Klingberg Resting State EEG Related to Mathematical Improvement After Spatial Training in Children Journal Article Frontiers in Human Neuroscience, 15 , pp. 379, 2021. Abstract \| Links @article{zhang2021resting, title = {Resting State EEG Related to Mathematical Improvement After Spatial Training in Children}, author = {Da-Wei Zhang and Anna Zaphf and Torkel Klingberg}, url = {https://www.frontiersin.org/articles/10.3389/fnhum.2021.698367/full}, year = {2021}, date = {2021-09-08}, journal = {Frontiers in Human Neuroscience}, volume = {15}, pages = {379}, publisher = {Frontiers}, abstract = {Spatial cognitive abilities, including mental rotation (MR) and visuo-spatial working memory (vsWM) are correlated with mathematical performance, and several studies have shown that training of these abilities can enhance mathematical performance. Here, we investigated the behavioral and neural correlates of MR and vsWM training combined with number line (NL) training. Fifty-seven children, aged 6–7, performed 25 days of NL training combined with either vsWM or MR and participated in an Electroencephalography (EEG)-session in school to measure resting state activity and steady-state visual evoked potentials during a vsWM task before and after training. Fifty children, aged 6–7, received usual teaching and acted as a control group. Compared to the control group, both training groups improved on a combined measure of mathematics. Cognitive improvement was specific to the training. Significant pre-post changes in resting state-EEG (rs-EEG), common to both training groups, were found for power as well as for coherence, with no significant differences in rs-EEG-changes between the vsWM and MR groups. Two of the common rs-EEG changes were correlated with mathematical improvement: (1) an increase in coherence between the central frontal lobe and the right parietal lobe in frequencies ranging from 16 to 25 Hz, and (2) an increase in coherence between the left frontal lobe and the right parietal lobe ranging from 23 to 25 Hz. These results indicate that changes in fronto-parietal coherence are related to an increase in mathematical performance, which thus might be a useful measure in further investigations of mathematical interventions in children.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Spatial cognitive abilities, including mental rotation (MR) and visuo-spatial working memory (vsWM) are correlated with mathematical performance, and several studies have shown that training of these abilities can enhance mathematical performance. Here, we investigated the behavioral and neural correlates of MR and vsWM training combined with number line (NL) training. Fifty-seven children, aged 6–7, performed 25 days of NL training combined with either vsWM or MR and participated in an Electroencephalography (EEG)-session in school to measure resting state activity and steady-state visual evoked potentials during a vsWM task before and after training. Fifty children, aged 6–7, received usual teaching and acted as a control group. Compared to the control group, both training groups improved on a combined measure of mathematics. Cognitive improvement was specific to the training. Significant pre-post changes in resting state-EEG (rs-EEG), common to both training groups, were found for power as well as for coherence, with no significant differences in rs-EEG-changes between the vsWM and MR groups. Two of the common rs-EEG changes were correlated with mathematical improvement: (1) an increase in coherence between the central frontal lobe and the right parietal lobe in frequencies ranging from 16 to 25 Hz, and (2) an increase in coherence between the left frontal lobe and the right parietal lobe ranging from 23 to 25 Hz. These results indicate that changes in fronto-parietal coherence are related to an increase in mathematical performance, which thus might be a useful measure in further investigations of mathematical interventions in children. Close https://www.frontiersin.org/articles/10.3389/fnhum.2021.698367/full Close
	Bruno Sauce, John Wiedenhoeft, Nicholas Judd, Torkel Klingberg Change by challenge: A common genetic basis behind childhood cognitive development and cognitive training Journal Article Nature Science of Learning, 2021. Abstract \| Links @article{Sauce2021, title = {Change by challenge: A common genetic basis behind childhood cognitive development and cognitive training}, author = {Bruno Sauce, John Wiedenhoeft, Nicholas Judd, Torkel Klingberg}, doi = {10.1038/s41539-021-00096-6}, year = {2021}, date = {2021-06-02}, journal = {Nature Science of Learning}, abstract = {The interplay of genetic and environmental factors behind cognitive development has preoccupied multiple fields of science and sparked heated debates over the decades. Here we tested the hypothesis that developmental genes rely heavily on cognitive challenges—as opposed to natural maturation. Starting with a polygenic score (cogPGS) that previously explained variation in cognitive performance in adults, we estimated its effect in 344 children and adolescents (mean age of 12 years old, ranging from 6 to 25) who showed changes in working memory (WM) in two distinct samples: (1) a developmental sample showing significant WM gains after 2 years of typical, age-related development, and (2) a training sample showing significant, experimentally-induced WM gains after 25 days of an intense WM training. We found that the same genetic factor, cogPGS, significantly explained the amount of WM gain in both samples. And there was no interaction of cogPGS with sample, suggesting that those genetic factors are neutral to whether the WM gains came from development or training. These results represent evidence that cognitive challenges are a central piece in the gene-environment interplay during cognitive development. We believe our study sheds new light on previous findings of interindividual differences in education (rich-get-richer and compensation effects), brain plasticity in children, and the heritability increase of intelligence across the lifespan.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The interplay of genetic and environmental factors behind cognitive development has preoccupied multiple fields of science and sparked heated debates over the decades. Here we tested the hypothesis that developmental genes rely heavily on cognitive challenges—as opposed to natural maturation. Starting with a polygenic score (cogPGS) that previously explained variation in cognitive performance in adults, we estimated its effect in 344 children and adolescents (mean age of 12 years old, ranging from 6 to 25) who showed changes in working memory (WM) in two distinct samples: (1) a developmental sample showing significant WM gains after 2 years of typical, age-related development, and (2) a training sample showing significant, experimentally-induced WM gains after 25 days of an intense WM training. We found that the same genetic factor, cogPGS, significantly explained the amount of WM gain in both samples. And there was no interaction of cogPGS with sample, suggesting that those genetic factors are neutral to whether the WM gains came from development or training. These results represent evidence that cognitive challenges are a central piece in the gene-environment interplay during cognitive development. We believe our study sheds new light on previous findings of interindividual differences in education (rich-get-richer and compensation effects), brain plasticity in children, and the heritability increase of intelligence across the lifespan. Close doi:10.1038/s41539-021-00096-6 Close
	Torkel Klingberg, Nicholas Judd, Bruno Sauce Assessing the impact of environmental factors on the adolescent brain: the importance of regional analyses and genetic controls Journal Article World Psychiatry, 2021. @article{Klingberg2021, title = {Assessing the impact of environmental factors on the adolescent brain: the importance of regional analyses and genetic controls}, author = {Torkel Klingberg, Nicholas Judd, Bruno Sauce}, year = {2021}, date = {2021-05-10}, journal = {World Psychiatry}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close
	Torkel Klingberg, Bruno Sauce Working memory training: From the laboratory to schools Book Chapter Borst, Gregoire (Ed.): Cambridge Handbook of Cognitive Development, 2021. @inbook{KlingbergBookC2020, title = {Working memory training: From the laboratory to schools}, author = {Torkel Klingberg, Bruno Sauce}, editor = {Gregoire Borst}, year = {2021}, date = {2021-05-04}, booktitle = {Cambridge Handbook of Cognitive Development}, keywords = {}, pubstate = {published}, tppubtype = {inbook} } Close
	Nicholas Judd, Torkel Klingberg Training spatial cognition enhances mathematical learning in a randomized study of 17,000 children Journal Article Nature Human Behaviour, 2021. Abstract \| Links @article{Judd2020b, title = {Training spatial cognition enhances mathematical learning in a randomized study of 17,000 children}, author = {Nicholas Judd, Torkel Klingberg}, doi = {10.1038/s41562-021-01118-4}, year = {2021}, date = {2021-05-01}, journal = {Nature Human Behaviour}, abstract = {Spatial and mathematical abilities are strongly associated. Here, we analysed data from 17,648 children, aged 6–8 years, who performed 7 weeks of mathematical training together with randomly assigned spatial cognitive training with tasks demanding more spatial manipulation (mental rotation or tangram), maintenance of spatial information (a visuospatial working memory task) or spatial, non-verbal reasoning. We found that the type of cognitive training children performed had a significant impact on mathematical learning, with training of visuospatial working memory and reasoning being the most effective. This large, community-based study shows that spatial cognitive training can result in transfer to academic abilities, and that reasoning ability and maintenance of spatial information is relevant for mathematics learning in young children.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Spatial and mathematical abilities are strongly associated. Here, we analysed data from 17,648 children, aged 6–8 years, who performed 7 weeks of mathematical training together with randomly assigned spatial cognitive training with tasks demanding more spatial manipulation (mental rotation or tangram), maintenance of spatial information (a visuospatial working memory task) or spatial, non-verbal reasoning. We found that the type of cognitive training children performed had a significant impact on mathematical learning, with training of visuospatial working memory and reasoning being the most effective. This large, community-based study shows that spatial cognitive training can result in transfer to academic abilities, and that reasoning ability and maintenance of spatial information is relevant for mathematics learning in young children. Close doi:10.1038/s41562-021-01118-4 Close
	Nicholas Judd, Torkel Klingberg, Douglas Sjöwall Working memory capacity, variability, and response to intervention at age 6 and its association to inattention and mathematics age 9 Journal Article Cognitive Development, 58 (12), pp. 101013, 2021. Abstract \| Links @article{Judd2021, title = {Working memory capacity, variability, and response to intervention at age 6 and its association to inattention and mathematics age 9}, author = {Nicholas Judd, Torkel Klingberg, Douglas Sjöwall}, url = {https://www.sciencedirect.com/science/article/pii/S0885201421000083}, doi = {https://doi.org/10.1016/j.cogdev.2021.101013}, year = {2021}, date = {2021-04-01}, journal = {Cognitive Development}, volume = {58}, number = {12}, pages = {101013}, abstract = {Classically, neuropsychological evaluation only estimates an individual’s performance at one time point. For example, working memory (WM) capacity is commonly determined in a single test session. However, recent research in WM plasticity and variability has suggested performance over several sessions/days might aid in evaluating children. Here, we explored four temporal properties of WM: WM measured once, as a mean over three days (multiple-session-baseline performance), variability over 8 weeks, and performance improvement over an 8-week WM training program. To examine independence we controlled for a single-session, multiple task WM assessment while predicting inattention and mathematics three years later (n = 178, mean age 80 months at training, 49 % boys). Our results showed improved prediction for mathematics from WM training improvement and variability, yet this was not the case for inattention. While the additional variance added was not substantial, our results indicate clinically relevant information present in these alternative WM measures.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Classically, neuropsychological evaluation only estimates an individual’s performance at one time point. For example, working memory (WM) capacity is commonly determined in a single test session. However, recent research in WM plasticity and variability has suggested performance over several sessions/days might aid in evaluating children. Here, we explored four temporal properties of WM: WM measured once, as a mean over three days (multiple-session-baseline performance), variability over 8 weeks, and performance improvement over an 8-week WM training program. To examine independence we controlled for a single-session, multiple task WM assessment while predicting inattention and mathematics three years later (n = 178, mean age 80 months at training, 49 % boys). Our results showed improved prediction for mathematics from WM training improvement and variability, yet this was not the case for inattention. While the additional variance added was not substantial, our results indicate clinically relevant information present in these alternative WM measures. Close https://www.sciencedirect.com/science/article/pii/S0885201421000083 doi:https://doi.org/10.1016/j.cogdev.2021.101013 Close
2020
	Carlos Guillermo Bozzoli, Maria Luz Gonzalez-Gadea, Maria Julia Hermida, Lucía Navarro, Tomás Olego, Torkel Klingberg Digital, mathematical and cognitive training: Evidence from a randomized trial Journal Article PsyArXiv, 2020. Abstract \| Links @article{Bozzoli2020b, title = {Digital, mathematical and cognitive training: Evidence from a randomized trial}, author = {Carlos Guillermo Bozzoli, Maria Luz Gonzalez-Gadea, Maria Julia Hermida, Lucía Navarro, Tomás Olego, Torkel Klingberg}, url = {https://psyarxiv.com/24ej7/}, doi = {10.31234/osf.io/24ej7}, year = {2020}, date = {2020-11-02}, journal = {PsyArXiv}, abstract = {In this paper, we experimentally evaluate a cognitive training tool that aims to improve children’s mathematical ability through technology in rural primary schools in Argentina. We conducted a large cluster-randomized trial: schools in the treatment group used an app to train mathematical skills, while schools in the control group received a literacy book. We tested the math skills of 1,304 children in the 2nd through 6th grades from 80 rural schools and applied three cognitive tests: digit-span (working memory), face-perception (attention to objects), and block design (visuospatial reasoning), directly before and after the 10-week intervention period. In schools that received the treatment, we found no improvement in the digit-span or face-perception tests, but significant and positive effects in visuospatial reasoning and mathematical abilities. The improvement among students from treatment schools was 54 percentage points higher in math skills and 42 percentage points higher in visuospatial abilities than the gains by students in control schools. This study suggests this intervention is a feasible and effective way of enhancing the mathematical and cognitive abilities of children in rural areas.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close In this paper, we experimentally evaluate a cognitive training tool that aims to improve children’s mathematical ability through technology in rural primary schools in Argentina. We conducted a large cluster-randomized trial: schools in the treatment group used an app to train mathematical skills, while schools in the control group received a literacy book. We tested the math skills of 1,304 children in the 2nd through 6th grades from 80 rural schools and applied three cognitive tests: digit-span (working memory), face-perception (attention to objects), and block design (visuospatial reasoning), directly before and after the 10-week intervention period. In schools that received the treatment, we found no improvement in the digit-span or face-perception tests, but significant and positive effects in visuospatial reasoning and mathematical abilities. The improvement among students from treatment schools was 54 percentage points higher in math skills and 42 percentage points higher in visuospatial abilities than the gains by students in control schools. This study suggests this intervention is a feasible and effective way of enhancing the mathematical and cognitive abilities of children in rural areas. Close https://psyarxiv.com/24ej7/ doi:10.31234/osf.io/24ej7 Close
	Carlos Bozzoli, Maria Gonzalez-Gadea, Maria Hermida, Lucía Navarro, Tomás Olego, Torkel Klingberg Digital, mathematical and cognitive training: Evidence from a randomized trial Journal Article PsyArXiv, 2020. Abstract \| Links @article{Bozzoli2020, title = {Digital, mathematical and cognitive training: Evidence from a randomized trial}, author = {Carlos Bozzoli, Maria Gonzalez-Gadea, Maria Hermida, Lucía Navarro, Tomás Olego, Torkel Klingberg}, url = {https://psyarxiv.com/24ej7/}, doi = {https://doi.org/10.31234/osf.io/24ej7}, year = {2020}, date = {2020-11-01}, journal = {PsyArXiv}, abstract = {In this paper, we experimentally evaluate a cognitive training tool that aims to improve children’s mathematical ability through technology in rural primary schools in Argentina. We conducted a large cluster-randomized trial: schools in the treatment group used an app to train mathematical skills, while schools in the control group received a literacy book. We tested the math skills of 1,304 children in the 2nd through 6th grades from 80 rural schools and applied three cognitive tests: digit-span (working memory), face-perception (attention to objects), and block design (visuospatial reasoning), directly before and after the 10-week intervention period. In schools that received the treatment, we found no improvement in the digit-span or face-perception tests, but significant and positive effects in visuospatial reasoning and mathematical abilities. The improvement among students from treatment schools was 54 percentage points higher in math skills and 42 percentage points higher in visuospatial abilities than the gains by students in control schools. This study suggests this intervention is a feasible and effective way of enhancing the mathematical and cognitive abilities of children in rural areas.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close In this paper, we experimentally evaluate a cognitive training tool that aims to improve children’s mathematical ability through technology in rural primary schools in Argentina. We conducted a large cluster-randomized trial: schools in the treatment group used an app to train mathematical skills, while schools in the control group received a literacy book. We tested the math skills of 1,304 children in the 2nd through 6th grades from 80 rural schools and applied three cognitive tests: digit-span (working memory), face-perception (attention to objects), and block design (visuospatial reasoning), directly before and after the 10-week intervention period. In schools that received the treatment, we found no improvement in the digit-span or face-perception tests, but significant and positive effects in visuospatial reasoning and mathematical abilities. The improvement among students from treatment schools was 54 percentage points higher in math skills and 42 percentage points higher in visuospatial abilities than the gains by students in control schools. This study suggests this intervention is a feasible and effective way of enhancing the mathematical and cognitive abilities of children in rural areas. Close https://psyarxiv.com/24ej7/ doi:https://doi.org/10.31234/osf.io/24ej7 Close
	George Zacharopoulos, Torkel Klingberg, Roi Cohen Kadosh Structural variation within the left globus pallidus is associated with task-switching, not stimulus updating or distractor filtering Journal Article Cognitive Neuroscience, 11 (4), pp. 229-238, 2020. Abstract \| Links @article{Zacharopoulos2020b, title = {Structural variation within the left globus pallidus is associated with task-switching, not stimulus updating or distractor filtering}, author = {George Zacharopoulos, Torkel Klingberg, Roi Cohen Kadosh}, url = {https://www.tandfonline.com/doi/full/10.1080/17588928.2020.1813699}, doi = {https://doi.org/10.1080/17588928.2020.1813699}, year = {2020}, date = {2020-10-01}, journal = {Cognitive Neuroscience}, volume = {11}, number = {4}, pages = {229-238}, abstract = {Cognitive control is a pivotal aspect of cognition and it is impaired in many clinical populations. To date, several distinct types of cognitive control have been proposed, and prior work demonstrated the instrumental role of basal ganglia, frontal and parietal regions. However, the role of the structural variation of these regions in cognitive control functions is poorly understood. Here, we examined in 39 adults the association between regional brain volume and three major types of cognitive control: (i) stimulus updating, (ii) task-switching, and (iii) distractor filtering. The volume of the globus pallidus was positively correlated with individual variation in task-switching , and was anatomically specific to the left hemisphere. Importantly, this region did not track performance in distractor filtering or stimulus updating. We then aimed to use transcranial direct current stimulation to target the left midline subcortical structures. However, we did not find an effect on task-switching. While the null effect in the brain stimulation prevents us from drawing causal inference from the role of globus pallidus on task-switching, our structural results reveal a novel and highly specific neurostructural mechanism for task-switching and provide a further understanding of the link between cognitive control functions and the human brain.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Cognitive control is a pivotal aspect of cognition and it is impaired in many clinical populations. To date, several distinct types of cognitive control have been proposed, and prior work demonstrated the instrumental role of basal ganglia, frontal and parietal regions. However, the role of the structural variation of these regions in cognitive control functions is poorly understood. Here, we examined in 39 adults the association between regional brain volume and three major types of cognitive control: (i) stimulus updating, (ii) task-switching, and (iii) distractor filtering. The volume of the globus pallidus was positively correlated with individual variation in task-switching , and was anatomically specific to the left hemisphere. Importantly, this region did not track performance in distractor filtering or stimulus updating. We then aimed to use transcranial direct current stimulation to target the left midline subcortical structures. However, we did not find an effect on task-switching. While the null effect in the brain stimulation prevents us from drawing causal inference from the role of globus pallidus on task-switching, our structural results reveal a novel and highly specific neurostructural mechanism for task-switching and provide a further understanding of the link between cognitive control functions and the human brain. Close https://www.tandfonline.com/doi/full/10.1080/17588928.2020.1813699 doi:https://doi.org/10.1080/17588928.2020.1813699 Close
	Nicholas Judd, Bruno Sauce, John Wiedenhoeft, Jeshua Tromp, Bader Chaarani, Alexander Schliep, Betteke van Noort, Jani Penttilä, Yvonne Grimmer, Corinna Insensee, Andreas Becker, Tobias Banaschewski, Arun L W Bokde, Erin Burke Quinlan, Sylvane Desrivières, Herta Flor, Antoine Grigis, Penny Gowland, Andreas Heinz, Bernd Ittermann, Jean-Luc Martinot, Marie-Laure Paillère Martinot, Eric Artiges, Frauke Nees, Dimitri Papadopoulos Orfanos, Tomáš Paus, Luise Poustka, Sarah Hohmann, Sabina Millenet, Juliane H Fröhner, Michael N Smolka, Henrik Walter, Robert Whelan, Gunter Schumann, Hugh Garavan, Torkel Klingberg Cognitive and brain development is independently influenced by socioeconomic status and polygenic scores for educational attainment Journal Article Proceedings of the National Academy of Sciences, 117 (22), pp. 12411–12418, 2020, ISSN: 0027-8424. Abstract \| Links @article{Judd2020, title = {Cognitive and brain development is independently influenced by socioeconomic status and polygenic scores for educational attainment}, author = {Nicholas Judd and Bruno Sauce and John Wiedenhoeft and Jeshua Tromp and Bader Chaarani and Alexander Schliep and Betteke van Noort and Jani Penttilä and Yvonne Grimmer and Corinna Insensee and Andreas Becker and Tobias Banaschewski and Arun L W Bokde and Erin Burke Quinlan and Sylvane Desrivi{è}res and Herta Flor and Antoine Grigis and Penny Gowland and Andreas Heinz and Bernd Ittermann and Jean-Luc Martinot and Marie-Laure {Paill{è}re Martinot} and Eric Artiges and Frauke Nees and Dimitri {Papadopoulos Orfanos} and Tomáš Paus and Luise Poustka and Sarah Hohmann and Sabina Millenet and Juliane H Fröhner and Michael N Smolka and Henrik Walter and Robert Whelan and Gunter Schumann and Hugh Garavan and Torkel Klingberg}, url = {http://www.pnas.org/lookup/doi/10.1073/pnas.2001228117}, doi = {10.1073/pnas.2001228117}, issn = {0027-8424}, year = {2020}, date = {2020-06-01}, journal = {Proceedings of the National Academy of Sciences}, volume = {117}, number = {22}, pages = {12411--12418}, abstract = {Genetic factors and socioeconomic status (SES) inequalities play a large role in educational attainment, and both have been associated with variations in brain structure and cognition. However, genetics and SES are correlated, and no prior study has assessed their neural associations independently. Here we used a polygenic score for educational attainment (EduYears-PGS), as well as SES, in a longitudinal study of 551 adolescents to tease apart genetic and environmental associations with brain development and cognition. Subjects received a structural MRI scan at ages 14 and 19. At both time points, they performed three working memory (WM) tasks. SES and EduYears-PGS were correlated ( r = 0.27) and had both common and independent associations with brain structure and cognition. Specifically, lower SES was related to less total cortical surface area and lower WM. EduYears-PGS was also related to total cortical surface area, but in addition had a regional association with surface area in the right parietal lobe, a region related to nonverbal cognitive functions, including mathematics, spatial cognition, and WM. SES, but not EduYears-PGS, was related to a change in total cortical surface area from age 14 to 19. This study demonstrates a regional association of EduYears-PGS and the independent prediction of SES with cognitive function and brain development. It suggests that the SES inequalities, in particular parental education, are related to global aspects of cortical development, and exert a persistent influence on brain development during adolescence.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Genetic factors and socioeconomic status (SES) inequalities play a large role in educational attainment, and both have been associated with variations in brain structure and cognition. However, genetics and SES are correlated, and no prior study has assessed their neural associations independently. Here we used a polygenic score for educational attainment (EduYears-PGS), as well as SES, in a longitudinal study of 551 adolescents to tease apart genetic and environmental associations with brain development and cognition. Subjects received a structural MRI scan at ages 14 and 19. At both time points, they performed three working memory (WM) tasks. SES and EduYears-PGS were correlated ( r = 0.27) and had both common and independent associations with brain structure and cognition. Specifically, lower SES was related to less total cortical surface area and lower WM. EduYears-PGS was also related to total cortical surface area, but in addition had a regional association with surface area in the right parietal lobe, a region related to nonverbal cognitive functions, including mathematics, spatial cognition, and WM. SES, but not EduYears-PGS, was related to a change in total cortical surface area from age 14 to 19. This study demonstrates a regional association of EduYears-PGS and the independent prediction of SES with cognitive function and brain development. It suggests that the SES inequalities, in particular parental education, are related to global aspects of cortical development, and exert a persistent influence on brain development during adolescence. Close http://www.pnas.org/lookup/doi/10.1073/pnas.2001228117 doi:10.1073/pnas.2001228117 Close
	George Zacharopoulos, Torkel Klingberg, Roi Cohen Kadosh Cortical surface area of the left frontal pole is associated with visuospatial working memory capacity Journal Article Neuropsychologia, 143 , 2020. Abstract \| Links @article{Zacharopoulos2020, title = {Cortical surface area of the left frontal pole is associated with visuospatial working memory capacity}, author = {George Zacharopoulos, Torkel Klingberg, Roi Cohen Kadosh}, url = {https://www.sciencedirect.com/science/article/pii/S0028393220301573}, doi = {https://doi.org/10.1016/j.neuropsychologia.2020.107486}, year = {2020}, date = {2020-06-01}, journal = {Neuropsychologia}, volume = {143}, abstract = {Working memory, the ability to maintain and manipulate information over seconds, is central to cognition and it is impaired in many clinical populations. However, our knowledge of the structural properties associated with individual variation in visuospatial working memory capacity is currently poor. Across two locations (Stockholm and Oxford), we examined how regional surface area and cortical thickness in frontal and parietal regions were related to visuospatial working memory capacity. We found a negative association between visuospatial working memory capacity and the surface area of the left frontal pole across both locations, and this finding was consistently present in each of the two locations separately. Importantly, this association was specific to (i) the surface area (not cortical thickness), (ii) the left side of the brain, (iii) and the visuospatial rather than the verbal modality. This result reveals a novel and highly specific neurobiological association with visuospatial working memory which could be further explored in studies with a wider range of psychological tests and in clinical populations.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Working memory, the ability to maintain and manipulate information over seconds, is central to cognition and it is impaired in many clinical populations. However, our knowledge of the structural properties associated with individual variation in visuospatial working memory capacity is currently poor. Across two locations (Stockholm and Oxford), we examined how regional surface area and cortical thickness in frontal and parietal regions were related to visuospatial working memory capacity. We found a negative association between visuospatial working memory capacity and the surface area of the left frontal pole across both locations, and this finding was consistently present in each of the two locations separately. Importantly, this association was specific to (i) the surface area (not cortical thickness), (ii) the left side of the brain, (iii) and the visuospatial rather than the verbal modality. This result reveals a novel and highly specific neurobiological association with visuospatial working memory which could be further explored in studies with a wider range of psychological tests and in clinical populations. Close https://www.sciencedirect.com/science/article/pii/S0028393220301573 doi:https://doi.org/10.1016/j.neuropsychologia.2020.107486 Close
2019
	Nicholas Judd, Bruno Sauce, John Wiedenhoeft, Jeshua Tromp, Bader Chaarani, Alexander Schliep, Argyris Stringaris, Betteke van Noort, Jani Penttilä, Yvonne Grimmer, Corinna Insensee, Andreas Becker, Tobias Banaschewski, Arun L W Bokde, Erin Burke Quinlan, Sylvane Desrivières, Herta Flor, Antoine Grigis, Penny Gowland, Bernd Ittermann, Jean-Luc Martinot, Marie-Laure Paillère Martinot, Eric Artiges, Frauke Nees, Dimitri Papadopoulos Orfanos, Tomáš Paus, Luise Poustka, Sarah Hohmann, Sabina Millenet, Juliane H Fröhner, Michael N Smolka, Henrik Walter, Robert Whelan, Gunter Schumann, Hugh Garavan, Torkel Klingberg Independent effects of socioeconomic status and genetics on adolescent cognition and brain development Journal Article bioRxiv, 2019. Abstract \| Links @article{Judd2019, title = {Independent effects of socioeconomic status and genetics on adolescent cognition and brain development}, author = {Nicholas Judd and Bruno Sauce and John Wiedenhoeft and Jeshua Tromp and Bader Chaarani and Alexander Schliep and Argyris Stringaris and Betteke van Noort and Jani Penttilä and Yvonne Grimmer and Corinna Insensee and Andreas Becker and Tobias Banaschewski and Arun L W Bokde and Erin Burke Quinlan and Sylvane Desrivi{è}res and Herta Flor and Antoine Grigis and Penny Gowland and Bernd Ittermann and Jean-Luc Martinot and Marie-Laure Paill{è}re Martinot and Eric Artiges and Frauke Nees and Dimitri Papadopoulos Orfanos and Tomáš Paus and Luise Poustka and Sarah Hohmann and Sabina Millenet and Juliane H Fröhner and Michael N Smolka and Henrik Walter and Robert Whelan and Gunter Schumann and Hugh Garavan and Torkel Klingberg}, doi = {10.1101/866624}, year = {2019}, date = {2019-12-06}, journal = {bioRxiv}, abstract = {Genetic factors and socioeconomic (SES) inequalities play a large role in educational attainment, and both have been associated with variations in brain structure and cognition. However, genetics and SES are correlated, and no prior study has assessed their neural effects independently. Here we used polygenic score for educational attainment (EduYears-PGS) as well as SES, in a longitudinal study of 551 adolescents, to tease apart genetic and environmental effects on brain development and cognition. Subjects received a structural MRI scan at ages 14 and 19. At both time-points, they performed three working memory (WM) tasks. SES and EduYears-PGS were correlated (r = 0.27) and had both common and independent effects on brain structure and cognition. Specifically, lower SES was related to less total cortical surface area and lower WM. EduYears-PGS was also related to total cortical surface area, but in addition had a regional effect on surface area in the right parietal lobe, a region related to nonverbal cognitive functions, including mathematics, problem solving and WM. SES, but not EduYears-PGS, affected the change in total cortical surface area from age 14 to 19. This is the first study demonstrating the regional effects of EduYears-PGS and the independent role of SES on cognitive function and brain development. It suggests that the SES effects are substantial, affect global aspects of cortical development, and exert a persistent influence on brain development during adolescence.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Genetic factors and socioeconomic (SES) inequalities play a large role in educational attainment, and both have been associated with variations in brain structure and cognition. However, genetics and SES are correlated, and no prior study has assessed their neural effects independently. Here we used polygenic score for educational attainment (EduYears-PGS) as well as SES, in a longitudinal study of 551 adolescents, to tease apart genetic and environmental effects on brain development and cognition. Subjects received a structural MRI scan at ages 14 and 19. At both time-points, they performed three working memory (WM) tasks. SES and EduYears-PGS were correlated (r = 0.27) and had both common and independent effects on brain structure and cognition. Specifically, lower SES was related to less total cortical surface area and lower WM. EduYears-PGS was also related to total cortical surface area, but in addition had a regional effect on surface area in the right parietal lobe, a region related to nonverbal cognitive functions, including mathematics, problem solving and WM. SES, but not EduYears-PGS, affected the change in total cortical surface area from age 14 to 19. This is the first study demonstrating the regional effects of EduYears-PGS and the independent role of SES on cognitive function and brain development. It suggests that the SES effects are substantial, affect global aspects of cortical development, and exert a persistent influence on brain development during adolescence. Close doi:10.1101/866624 Close
	Fahimeh Darki, Bruno Sauce, Torkel Klingberg Inter-Individual Differences in Striatal Connectivity Is Related to Executive Function Through Fronto-Parietal Connectivity Journal Article Cerebral Cortex, pp. 1–10, 2019, ISSN: 1047-3211. Abstract \| Links @article{Darki2019, title = {Inter-Individual Differences in Striatal Connectivity Is Related to Executive Function Through Fronto-Parietal Connectivity}, author = {Fahimeh Darki and Bruno Sauce and Torkel Klingberg}, url = {https://academic.oup.com/cercor/advance-article/doi/10.1093/cercor/bhz117/5543637}, doi = {10.1093/cercor/bhz117}, issn = {1047-3211}, year = {2019}, date = {2019-08-01}, journal = {Cerebral Cortex}, pages = {1--10}, abstract = {The striatum has long been associated with cognitive functions, but the mechanisms behind this are still unclear. Here we tested a new hypothesis that the striatum contributes to executive function (EF) by strengthening cortico-cortical connections. Striatal connectivity was evaluated by measuring the resting-state functional connectivity between ventral and dorsal striatum in 570 individuals, aged 3–20 years. Using structural equation modeling, we found that inter-individual differences in striatal connectivity had an indirect effect (via fronto-parietal functional connectivity) and a direct effect on a compound EF measure of working memory, inhibition, and set-shifting/flexibility. The effect of fronto-parietal connectivity on cognition did not depend on age: the influence was as strong in older as younger children. In contrast, striatal connectivity was closely related to changes in cognitive ability during childhood development, suggesting a specific role of the striatum in cognitive plasticity. These results support a new principle for striatal functioning, according to which striatum promotes cognitive development by strengthening of cortico-cortical connectivity.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The striatum has long been associated with cognitive functions, but the mechanisms behind this are still unclear. Here we tested a new hypothesis that the striatum contributes to executive function (EF) by strengthening cortico-cortical connections. Striatal connectivity was evaluated by measuring the resting-state functional connectivity between ventral and dorsal striatum in 570 individuals, aged 3–20 years. Using structural equation modeling, we found that inter-individual differences in striatal connectivity had an indirect effect (via fronto-parietal functional connectivity) and a direct effect on a compound EF measure of working memory, inhibition, and set-shifting/flexibility. The effect of fronto-parietal connectivity on cognition did not depend on age: the influence was as strong in older as younger children. In contrast, striatal connectivity was closely related to changes in cognitive ability during childhood development, suggesting a specific role of the striatum in cognitive plasticity. These results support a new principle for striatal functioning, according to which striatum promotes cognitive development by strengthening of cortico-cortical connectivity. Close https://academic.oup.com/cercor/advance-article/doi/10.1093/cercor/bhz117/554363[...] doi:10.1093/cercor/bhz117 Close
	C Shawn Green, Daphne Bavelier, Arthur F Kramer, Sophia Vinogradov, Ulrich Ansorge, Karlene K Ball, Ulrike Bingel, Jason M Chein, Lorenza S Colzato, Jerri D Edwards, Andrea Facoetti, Adam Gazzaley, Susan E Gathercole, Paolo Ghisletta, Simone Gori, Isabela Granic, Charles H Hillman, Bernhard Hommel, Susanne M Jaeggi, Philipp Kanske, Julia Karbach, Alan Kingstone, Matthias Kliegel, Torkel Klingberg, Simone Kühn, Dennis M Levi, Richard E Mayer, Anne Collins McLaughlin, Danielle S McNamara, Martha Clare Morris, Mor Nahum, Nora S Newcombe, Rogerio Panizzutti, Ruchika Shaurya Prakash, Albert Rizzo, Torsten Schubert, Aaron R Seitz, Sarah J Short, Ilina Singh, James D Slotta, Tilo Strobach, Michael S C Thomas, Elizabeth Tipton, Xin Tong, Haley A Vlach, Julie Loebach Wetherell, Anna Wexler, Claudia M Witt Improving Methodological Standards in Behavioral Interventions for Cognitive Enhancement Journal Article Journal of Cognitive Enhancement, 3 (1), pp. 2–29, 2019, ISSN: 2509-3290. Abstract \| Links @article{ShawnGreen2019, title = {Improving Methodological Standards in Behavioral Interventions for Cognitive Enhancement}, author = {C {Shawn Green} and Daphne Bavelier and Arthur F Kramer and Sophia Vinogradov and Ulrich Ansorge and Karlene K Ball and Ulrike Bingel and Jason M Chein and Lorenza S Colzato and Jerri D Edwards and Andrea Facoetti and Adam Gazzaley and Susan E Gathercole and Paolo Ghisletta and Simone Gori and Isabela Granic and Charles H Hillman and Bernhard Hommel and Susanne M Jaeggi and Philipp Kanske and Julia Karbach and Alan Kingstone and Matthias Kliegel and Torkel Klingberg and Simone Kühn and Dennis M Levi and Richard E Mayer and Anne Collins McLaughlin and Danielle S McNamara and Martha Clare Morris and Mor Nahum and Nora S Newcombe and Rogerio Panizzutti and Ruchika Shaurya Prakash and Albert Rizzo and Torsten Schubert and Aaron R Seitz and Sarah J Short and Ilina Singh and James D Slotta and Tilo Strobach and Michael S C Thomas and Elizabeth Tipton and Xin Tong and Haley A Vlach and Julie Loebach Wetherell and Anna Wexler and Claudia M Witt}, url = {http://link.springer.com/10.1007/s41465-018-0115-y}, doi = {10.1007/s41465-018-0115-y}, issn = {2509-3290}, year = {2019}, date = {2019-03-01}, journal = {Journal of Cognitive Enhancement}, volume = {3}, number = {1}, pages = {2--29}, publisher = {Springer International Publishing}, abstract = {There is substantial interest in the possibility that cognitive skills can be improved by dedicated behavioral training. Yet despite the large amount of work being conducted in this domain, there is not an explicit and widely agreed upon consensus around the best methodological practices. This document seeks to fill this gap. We start from the perspective that there are many types of studies that are important in this domain—e.g., feasibility, mechanistic, efficacy, and effectiveness. These studies have fundamentally different goals, and, as such, the best-practice methods to meet those goals will also differ. We thus make suggestions in topics ranging from the design and implementation of control groups, to reporting of results, to dissemination and communication, taking the perspective that the best practices are not necessarily uniform across all study types. We also explicitly recognize and discuss the fact that there are methodological issues around which we currently lack the theoretical and/or empirical foundation to determine best practices (e.g., as pertains to assessing participant expectations). For these, we suggest important routes forward, including greater interdisciplinary collaboration with individuals from domains that face related concerns. Our hope is that these recommendations will greatly increase the rate at which science in this domain advances.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close There is substantial interest in the possibility that cognitive skills can be improved by dedicated behavioral training. Yet despite the large amount of work being conducted in this domain, there is not an explicit and widely agreed upon consensus around the best methodological practices. This document seeks to fill this gap. We start from the perspective that there are many types of studies that are important in this domain—e.g., feasibility, mechanistic, efficacy, and effectiveness. These studies have fundamentally different goals, and, as such, the best-practice methods to meet those goals will also differ. We thus make suggestions in topics ranging from the design and implementation of control groups, to reporting of results, to dissemination and communication, taking the perspective that the best practices are not necessarily uniform across all study types. We also explicitly recognize and discuss the fact that there are methodological issues around which we currently lack the theoretical and/or empirical foundation to determine best practices (e.g., as pertains to assessing participant expectations). For these, we suggest important routes forward, including greater interdisciplinary collaboration with individuals from domains that face related concerns. Our hope is that these recommendations will greatly increase the rate at which science in this domain advances. Close http://link.springer.com/10.1007/s41465-018-0115-y doi:10.1007/s41465-018-0115-y Close
	Lotfi Khemiri, Christoffer Brynte, Angela Stunkel, Torkel Klingberg, Nitya Jayaram-Lindström Working Memory Training in Alcohol Use Disorder: A Randomized Controlled Trial Journal Article Alcoholism: Clinical and Experimental Research, 43 (1), pp. 135–146, 2019, ISSN: 01456008. Abstract \| Links @article{Khemiri2019, title = {Working Memory Training in Alcohol Use Disorder: A Randomized Controlled Trial}, author = {Lotfi Khemiri and Christoffer Brynte and Angela Stunkel and Torkel Klingberg and Nitya Jayaram-Lindström}, url = {http://doi.wiley.com/10.1111/acer.13910}, doi = {10.1111/acer.13910}, issn = {01456008}, year = {2019}, date = {2019-01-01}, journal = {Alcoholism: Clinical and Experimental Research}, volume = {43}, number = {1}, pages = {135--146}, abstract = {BACKGROUND: Alcohol use disorder (AUD) is associated with cognitive deficits such as impaired executive functions, which are hypothesized to contribute to the progression of the disease and worsen treatment outcome. Training of working memory (WM) to improve cognitive functions and thereby reduce alcohol use has been proposed as a novel treatment strategy. METHODS: Patients with AUD (n = 50) who were recruited to an outpatient addiction clinic were randomized to receive 5 weeks of active WM training or control training. Participants had weekly follow-up visits, and all cognitive training sessions were done online at home. Primary outcomes were WM function and change in self-reported heavy drinking. Secondary outcomes were craving, other drinking outcomes, and performance on a range of neuropsychological tasks from the Cambridge Neuropsychological Test Automated Battery. RESULTS: The active training group demonstrated a significantly greater improvement in verbal WM compared with the control group. No statistically significant effect of training was found on the primary drinking outcome, but a trend was observed indicating that WM training reduces the number of drinks per drinking occasion. WM training had no statistically significant effect on any of the other neuropsychological tasks. CONCLUSIONS: Cognitive training can improve WM function in individuals with AUD, suggesting that such interventions are feasible to administer in this patient population. The results do not support an effect of WM training on heavy drinking or transfer effects to other cognitive domains. Future studies should evaluate WM training as an adjunct to evidence-based treatments for AUD to assess potential synergistic effects.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close BACKGROUND: Alcohol use disorder (AUD) is associated with cognitive deficits such as impaired executive functions, which are hypothesized to contribute to the progression of the disease and worsen treatment outcome. Training of working memory (WM) to improve cognitive functions and thereby reduce alcohol use has been proposed as a novel treatment strategy. METHODS: Patients with AUD (n = 50) who were recruited to an outpatient addiction clinic were randomized to receive 5 weeks of active WM training or control training. Participants had weekly follow-up visits, and all cognitive training sessions were done online at home. Primary outcomes were WM function and change in self-reported heavy drinking. Secondary outcomes were craving, other drinking outcomes, and performance on a range of neuropsychological tasks from the Cambridge Neuropsychological Test Automated Battery. RESULTS: The active training group demonstrated a significantly greater improvement in verbal WM compared with the control group. No statistically significant effect of training was found on the primary drinking outcome, but a trend was observed indicating that WM training reduces the number of drinks per drinking occasion. WM training had no statistically significant effect on any of the other neuropsychological tasks. CONCLUSIONS: Cognitive training can improve WM function in individuals with AUD, suggesting that such interventions are feasible to administer in this patient population. The results do not support an effect of WM training on heavy drinking or transfer effects to other cognitive domains. Future studies should evaluate WM training as an adjunct to evidence-based treatments for AUD to assess potential synergistic effects. Close http://doi.wiley.com/10.1111/acer.13910 doi:10.1111/acer.13910 Close
2018
	Martin Hassler Hallstedt, Torkel Klingberg, Ata Ghaderi Short and long-term effects of a mathematics tablet intervention for low performing second graders. Journal Article Journal of Educational Psychology, 110 (8), pp. 1127–1148, 2018, ISSN: 1939-2176. Abstract \| Links @article{Hallstedt2018, title = {Short and long-term effects of a mathematics tablet intervention for low performing second graders.}, author = {Martin {Hassler Hallstedt} and Torkel Klingberg and Ata Ghaderi}, url = {http://doi.apa.org/getdoi.cfm?doi=10.1037/edu0000264}, doi = {10.1037/edu0000264}, issn = {1939-2176}, year = {2018}, date = {2018-11-01}, journal = {Journal of Educational Psychology}, volume = {110}, number = {8}, pages = {1127--1148}, abstract = {Using a randomized placebo controlled design, we examined the direct and follow-up effects (at 6 and 12 months) of a mathematics tablet intervention. Math training focused primarily on basic arithmetic (addition and subtraction facts up to 12), and secondarily on number knowledge and word problems. We investigated the moderating effects of IQ and socioeconomic factors, and additive effects of working memory (WM) training. A representative sample of 283 low performing second-grade students were randomly assigned to control ( n = 52), reading placebo ( n = 78), math intervention (MA; n = 76), or math plus WM training (MA + WM; n = 77). Both math conditions scored significantly higher than control and placebo on the posttest of basic arithmetic, but not on arithmetic transfer and problem solving. WM training did not show additive effects. Given the virtually identical patterns, we collapsed the control and placebo, respectively, MA and MA + WM conditions. The collapsed MA/MA + WM condition demonstrated significant medium-sized effects ( d = 0.53–0.67) on basic arithmetic compared with the collapsed control/placebo condition at posttest. There was a fadeout of effects at 6-month follow-up ( d = 0.18–0.28), that declined further at 12 months ( d = 0.03–0.13). IQ was a significant moderator of direct and long-term effects on addition up to 12 and subtraction up to 18, where students with lower IQ benefitted more than higher IQ students. Socioeconomic factors did not moderate outcome. The intervention effectively improved basic arithmetic among low performing second graders. Although the effects waned at 6-month follow-up, there was some indication that children with lower IQ demonstrated sustained gains. (PsycINFO Database Record (c) 2018 APA, all rights reserved) (Source: journal abstract) Impact statementEducational Impact and Implications Statement: This study shows that adaptive math training on tablet can help low performing 8-year-olds catch up about half a year of schooling in critical math skills. Students with lower IQ benefitted in particular and made long-term gains 12 months after training finished. Additional short-term memory training did not result in further math improvement. Because math is a strong predictor of later school achievement, these findings highlight the potential of well-designed adaptive teaching on tablets to significantly improve students' success at school. Evidence-based programs covering the bulk of elementary math might be widely spread, potentially at a low cost. (PsycINFO Database Record (c) 2018 APA, all rights reserved)}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Using a randomized placebo controlled design, we examined the direct and follow-up effects (at 6 and 12 months) of a mathematics tablet intervention. Math training focused primarily on basic arithmetic (addition and subtraction facts up to 12), and secondarily on number knowledge and word problems. We investigated the moderating effects of IQ and socioeconomic factors, and additive effects of working memory (WM) training. A representative sample of 283 low performing second-grade students were randomly assigned to control ( n = 52), reading placebo ( n = 78), math intervention (MA; n = 76), or math plus WM training (MA + WM; n = 77). Both math conditions scored significantly higher than control and placebo on the posttest of basic arithmetic, but not on arithmetic transfer and problem solving. WM training did not show additive effects. Given the virtually identical patterns, we collapsed the control and placebo, respectively, MA and MA + WM conditions. The collapsed MA/MA + WM condition demonstrated significant medium-sized effects ( d = 0.53–0.67) on basic arithmetic compared with the collapsed control/placebo condition at posttest. There was a fadeout of effects at 6-month follow-up ( d = 0.18–0.28), that declined further at 12 months ( d = 0.03–0.13). IQ was a significant moderator of direct and long-term effects on addition up to 12 and subtraction up to 18, where students with lower IQ benefitted more than higher IQ students. Socioeconomic factors did not moderate outcome. The intervention effectively improved basic arithmetic among low performing second graders. Although the effects waned at 6-month follow-up, there was some indication that children with lower IQ demonstrated sustained gains. (PsycINFO Database Record (c) 2018 APA, all rights reserved) (Source: journal abstract) Impact statementEducational Impact and Implications Statement: This study shows that adaptive math training on tablet can help low performing 8-year-olds catch up about half a year of schooling in critical math skills. Students with lower IQ benefitted in particular and made long-term gains 12 months after training finished. Additional short-term memory training did not result in further math improvement. Because math is a strong predictor of later school achievement, these findings highlight the potential of well-designed adaptive teaching on tablets to significantly improve students' success at school. Evidence-based programs covering the bulk of elementary math might be widely spread, potentially at a low cost. (PsycINFO Database Record (c) 2018 APA, all rights reserved) Close http://doi.apa.org/getdoi.cfm?doi=10.1037/edu0000264 doi:10.1037/edu0000264 Close
	Federico Nemmi, Margot A Schel, Torkel Klingberg Connectivity of the Human Number Form Area Reveals Development of a Cortical Network for Mathematics Journal Article Frontiers in Human Neuroscience, 12 (November), pp. 1–15, 2018, ISSN: 1662-5161. Abstract \| Links @article{Nemmi2018a, title = {Connectivity of the Human Number Form Area Reveals Development of a Cortical Network for Mathematics}, author = {Federico Nemmi and Margot A Schel and Torkel Klingberg}, url = {https://www.frontiersin.org/article/10.3389/fnhum.2018.00465/full}, doi = {10.3389/fnhum.2018.00465}, issn = {1662-5161}, year = {2018}, date = {2018-11-01}, journal = {Frontiers in Human Neuroscience}, volume = {12}, number = {November}, pages = {1--15}, abstract = {The adult brain contains cortical areas thought to be specialized for the analysis of numbers (the putative number form area, NFA) and letters (the visual word form area, VWFA). Although functional development of the VWFA has been investigated, it is largely unknown when and how the NFA becomes specialized and connected to the rest of the brain. One hypothesis is that NFA and VWFA derive their special functions through differential connectivity, but the development of this differential connectivity has not been shown. Here we mapped the resting state connectivity of NFA and VWFA to the rest of the brain in a large sample (n = 437) of individuals (age 3.2 – 21 years). We show that within NFA-math network and within VWFA-reading network the strength of connectivity increases with age. The right NFA is significantly connected to the right intraparietal cortex already at the earliest age tested (age 3), before formal mathematical education has begun. This connection might support or enable an early understanding of magnitude or numerosity In contrast, the functional connectivity from NFA to the left anterior intraparietal cortex and to the right dorsolateral prefrontal cortex is not different from the functional connectivity of VWFA to these regions until around 12-14 years of age. The increase in connectivity to these regions was associated with a gradual increase in mathematical ability in an independent sample. In contrast, VWFA connects significantly to Broca's region around age 6, and this connectivity is correlated with reading ability. These results show how the differential connectivity of the networks for mathematics and reading slowly emerges through years of training and education.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The adult brain contains cortical areas thought to be specialized for the analysis of numbers (the putative number form area, NFA) and letters (the visual word form area, VWFA). Although functional development of the VWFA has been investigated, it is largely unknown when and how the NFA becomes specialized and connected to the rest of the brain. One hypothesis is that NFA and VWFA derive their special functions through differential connectivity, but the development of this differential connectivity has not been shown. Here we mapped the resting state connectivity of NFA and VWFA to the rest of the brain in a large sample (n = 437) of individuals (age 3.2 – 21 years). We show that within NFA-math network and within VWFA-reading network the strength of connectivity increases with age. The right NFA is significantly connected to the right intraparietal cortex already at the earliest age tested (age 3), before formal mathematical education has begun. This connection might support or enable an early understanding of magnitude or numerosity In contrast, the functional connectivity from NFA to the left anterior intraparietal cortex and to the right dorsolateral prefrontal cortex is not different from the functional connectivity of VWFA to these regions until around 12-14 years of age. The increase in connectivity to these regions was associated with a gradual increase in mathematical ability in an independent sample. In contrast, VWFA connects significantly to Broca's region around age 6, and this connectivity is correlated with reading ability. These results show how the differential connectivity of the networks for mathematics and reading slowly emerges through years of training and education. Close https://www.frontiersin.org/article/10.3389/fnhum.2018.00465/full doi:10.3389/fnhum.2018.00465 Close
	N Kalnak, S Stamouli, M Peyrard-Janvid, I Rabkina, M Becker, T Klingberg, J Kere, H Forssberg, K Tammimies Enrichment of rare copy number variation in children with developmental language disorder Journal Article Clinical Genetics, 94 (3-4), pp. 313–320, 2018, ISSN: 00099163. Abstract \| Links @article{Kalnak2018, title = {Enrichment of rare copy number variation in children with developmental language disorder}, author = {N Kalnak and S Stamouli and M Peyrard-Janvid and I Rabkina and M Becker and T Klingberg and J Kere and H Forssberg and K Tammimies}, url = {http://doi.wiley.com/10.1111/cge.13389}, doi = {10.1111/cge.13389}, issn = {00099163}, year = {2018}, date = {2018-10-01}, journal = {Clinical Genetics}, volume = {94}, number = {3-4}, pages = {313--320}, abstract = {Developmental Language Disorder (DLD) is a common neurodevelopmental disorder with largely unknown etiology. Rare copy number variants (CNVs) have been implicated in the genetic architecture of other neurodevelopmental disorders (NDDs) which have led to clinical genetic testing recommendations for these disorders; however, the evidence is still lacking for DLD. We analyzed rare and de novo CNVs in 58 probands with severe DLD, their 159 family members and 76 Swedish typically developing children using high-resolution microarray. DLD probands had larger rare CNVs as measured by total length (p=0.05), and average length (p=0.04). Additionally, the rate of rare CNVs overlapping coding genes was increased (p=0.03 and p=0.01) and in average more genes were affected (p=0.006 and p=0.03) in the probands and their siblings, respectively. De novo CNVs were found in 4.8% DLD probands (2/42) and 2.4% (1/42) siblings. Clinically significant CNVs or chromosomal anomalies were found in 6.9% (4/58) of the probands of which two carried 16p11.2 deletions. We provide further evidence that rare CNVs contribute to the etiology of DLD in loci that overlap with other NDDs. Based on our results and earlier literature, families with DLD should be offered molecular genetic testing as a routine in their clinical follow-up. This article is protected by copyright. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Developmental Language Disorder (DLD) is a common neurodevelopmental disorder with largely unknown etiology. Rare copy number variants (CNVs) have been implicated in the genetic architecture of other neurodevelopmental disorders (NDDs) which have led to clinical genetic testing recommendations for these disorders; however, the evidence is still lacking for DLD. We analyzed rare and de novo CNVs in 58 probands with severe DLD, their 159 family members and 76 Swedish typically developing children using high-resolution microarray. DLD probands had larger rare CNVs as measured by total length (p=0.05), and average length (p=0.04). Additionally, the rate of rare CNVs overlapping coding genes was increased (p=0.03 and p=0.01) and in average more genes were affected (p=0.006 and p=0.03) in the probands and their siblings, respectively. De novo CNVs were found in 4.8% DLD probands (2/42) and 2.4% (1/42) siblings. Clinically significant CNVs or chromosomal anomalies were found in 6.9% (4/58) of the probands of which two carried 16p11.2 deletions. We provide further evidence that rare CNVs contribute to the etiology of DLD in loci that overlap with other NDDs. Based on our results and earlier literature, families with DLD should be offered molecular genetic testing as a routine in their clinical follow-up. This article is protected by copyright. All rights reserved. Close http://doi.wiley.com/10.1111/cge.13389 doi:10.1111/cge.13389 Close
	Fahimeh Darki, Torkel Klingberg Functional differentiation between convergence and non-convergence zones of the striatum in children Journal Article NeuroImage, 173 (January), pp. 384–393, 2018, ISSN: 10538119. Abstract \| Links @article{Darki2018, title = {Functional differentiation between convergence and non-convergence zones of the striatum in children}, author = {Fahimeh Darki and Torkel Klingberg}, url = {https://linkinghub.elsevier.com/retrieve/pii/S1053811918301617}, doi = {10.1016/j.neuroimage.2018.02.054}, issn = {10538119}, year = {2018}, date = {2018-06-01}, journal = {NeuroImage}, volume = {173}, number = {January}, pages = {384--393}, abstract = {Most cortical areas send projections to the striatum. In some parts of the striatum, the connections converge from several cortical areas. It is unknown whether the convergence and non-convergence zones of the striatum differ functionally. Here, we used diffusion-weighted magnetic resonance imaging and probabilistic fiber tracking to parcellate the striatum based on its connections to dorsolateral prefrontal, parietal and orbitofrontal cortices in two different datasets (children aged 6–7 years and adults). In both samples, quantitative susceptibility mapping (QSM) values were significantly correlated with working memory (WM) in convergence zones, but not in non-convergence zones. In children, this was also true for mean diffusivity, MD. The association of MD to WM specifically in the convergent zone was replicated in the Pediatric Imaging, Neurocognition, and Genetics (PING) dataset for 135 children aged 6–9 years. QSM data was not available in the PING dataset, and the association to QSM still needs to be replicated. These results suggest that connectivity-based segments of the striatum exhibit functionally different characteristics. The association between convergence zones and WM performance might relate to a role in integrating and coordinating activity in different cortical areas.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Most cortical areas send projections to the striatum. In some parts of the striatum, the connections converge from several cortical areas. It is unknown whether the convergence and non-convergence zones of the striatum differ functionally. Here, we used diffusion-weighted magnetic resonance imaging and probabilistic fiber tracking to parcellate the striatum based on its connections to dorsolateral prefrontal, parietal and orbitofrontal cortices in two different datasets (children aged 6–7 years and adults). In both samples, quantitative susceptibility mapping (QSM) values were significantly correlated with working memory (WM) in convergence zones, but not in non-convergence zones. In children, this was also true for mean diffusivity, MD. The association of MD to WM specifically in the convergent zone was replicated in the Pediatric Imaging, Neurocognition, and Genetics (PING) dataset for 135 children aged 6–9 years. QSM data was not available in the PING dataset, and the association to QSM still needs to be replicated. These results suggest that connectivity-based segments of the striatum exhibit functionally different characteristics. The association between convergence zones and WM performance might relate to a role in integrating and coordinating activity in different cortical areas. Close https://linkinghub.elsevier.com/retrieve/pii/S1053811918301617 doi:10.1016/j.neuroimage.2018.02.054 Close
	F Nemmi, C Nymberg, F Darki, T Banaschewski, A L W Bokde, C Büchel, H Flor, V Frouin, H Garavan, P Gowland, A Heinz, J -L Martinot, F Nees, T Paus, M N Smolka, T W Robbins, G Schumann, Torkel Klingberg Interaction between striatal volume and DAT1 polymorphism predicts working memory development during adolescence Journal Article Developmental Cognitive Neuroscience, 30 (February), pp. 191–199, 2018, ISSN: 18789293. Abstract \| Links @article{Nemmi2018b, title = {Interaction between striatal volume and DAT1 polymorphism predicts working memory development during adolescence}, author = {F Nemmi and C Nymberg and F Darki and T Banaschewski and A L W Bokde and C Büchel and H Flor and V Frouin and H Garavan and P Gowland and A Heinz and J -L Martinot and F Nees and T Paus and M N Smolka and T W Robbins and G Schumann and Torkel Klingberg}, url = {https://doi.org/10.1016/j.dcn.2018.03.006 https://linkinghub.elsevier.com/retrieve/pii/S1878929317301536}, doi = {10.1016/j.dcn.2018.03.006}, issn = {18789293}, year = {2018}, date = {2018-04-01}, journal = {Developmental Cognitive Neuroscience}, volume = {30}, number = {February}, pages = {191--199}, publisher = {Elsevier}, abstract = {There is considerable inter-individual variability in the rate at which working memory (WM) develops during childhood and adolescence, but the neural and genetic basis for these differences are poorly understood. Dopamine-related genes, striatal activation and morphology have been associated with increased WM capacity after training. Here we tested the hypothesis that these factors would also explain some of the inter-individual differences in the rate of WM development. We measured WM performance in 487 healthy subjects twice: at age 14 and 19. At age 14 subjects underwent a structural MRI scan, and genotyping of five single nucleotide polymorphisms (SNPs) in or close to the dopamine genes DRD2, DAT-1 and COMT, which have previously been associated with gains in WM after WM training. We then analyzed which biological factors predicted the rate of increase in WM between ages 14 and 19. We found a significant interaction between putamen size and DAT1/SLC6A3 rs40184 polymorphism, such that TC heterozygotes with a larger putamen at age 14 showed greater WM improvement at age 19. The effect of the DAT1 polymorphism on WM development was exerted in interaction with striatal morphology. These results suggest that development of WM partially share neuro-physiological mechanism with training-induced plasticity.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close There is considerable inter-individual variability in the rate at which working memory (WM) develops during childhood and adolescence, but the neural and genetic basis for these differences are poorly understood. Dopamine-related genes, striatal activation and morphology have been associated with increased WM capacity after training. Here we tested the hypothesis that these factors would also explain some of the inter-individual differences in the rate of WM development. We measured WM performance in 487 healthy subjects twice: at age 14 and 19. At age 14 subjects underwent a structural MRI scan, and genotyping of five single nucleotide polymorphisms (SNPs) in or close to the dopamine genes DRD2, DAT-1 and COMT, which have previously been associated with gains in WM after WM training. We then analyzed which biological factors predicted the rate of increase in WM between ages 14 and 19. We found a significant interaction between putamen size and DAT1/SLC6A3 rs40184 polymorphism, such that TC heterozygotes with a larger putamen at age 14 showed greater WM improvement at age 19. The effect of the DAT1 polymorphism on WM development was exerted in interaction with striatal morphology. These results suggest that development of WM partially share neuro-physiological mechanism with training-induced plasticity. Close https://doi.org/10.1016/j.dcn.2018.03.006 https://linkinghub.elsevier.com/retrie[...] doi:10.1016/j.dcn.2018.03.006 Close
2017
	Fahimeh Darki, Satu Massinen, Elina Salmela, Hans Matsson, Myriam Peyrard-Janvid, Torkel Klingberg, Juha Kere Human ROBO1 regulates white matter structure in corpus callosum Journal Article Brain Structure and Function, 222 (2), pp. 707–716, 2017, ISSN: 18632661. Abstract \| Links @article{Darki2017, title = {Human ROBO1 regulates white matter structure in corpus callosum}, author = {Fahimeh Darki and Satu Massinen and Elina Salmela and Hans Matsson and Myriam Peyrard-Janvid and Torkel Klingberg and Juha Kere}, doi = {10.1007/s00429-016-1240-y}, issn = {18632661}, year = {2017}, date = {2017-01-01}, journal = {Brain Structure and Function}, volume = {222}, number = {2}, pages = {707--716}, publisher = {Springer Berlin Heidelberg}, abstract = {textcopyright 2016, The Author(s). The axon guidance receptor, Robo1, controls the pathfinding of callosal axons in mice. To determine whether the orthologous ROBO1 gene is involved in callosal development also in humans, we studied polymorphisms in the ROBO1 gene and variation in the white matter structure in the corpus callosum using both structural magnetic resonance imaging and diffusion tensor magnetic resonance imaging. We found that five polymorphisms in the regulatory region of ROBO1 were associated with white matter density in the posterior part of the corpus callosum pathways. One of the polymorphisms, rs7631357, was also significantly associated with the probability of connections to the parietal cortical regions. Our results demonstrate that human ROBO1 may be involved in the regulation of the structure and connectivity of posterior part of corpus callosum.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close textcopyright 2016, The Author(s). The axon guidance receptor, Robo1, controls the pathfinding of callosal axons in mice. To determine whether the orthologous ROBO1 gene is involved in callosal development also in humans, we studied polymorphisms in the ROBO1 gene and variation in the white matter structure in the corpus callosum using both structural magnetic resonance imaging and diffusion tensor magnetic resonance imaging. We found that five polymorphisms in the regulatory region of ROBO1 were associated with white matter density in the posterior part of the corpus callosum pathways. One of the polymorphisms, rs7631357, was also significantly associated with the probability of connections to the parietal cortical regions. Our results demonstrate that human ROBO1 may be involved in the regulation of the structure and connectivity of posterior part of corpus callosum. Close doi:10.1007/s00429-016-1240-y Close
	Elisabet Einarsdottir, Myriam Peyrard-Janvid, Fahimeh Darki, Jetro J Tuulari, Harri Merisaari, Linnea Karlsson, Noora M Scheinin, Jani Saunavaara, Riitta Parkkola, Katri Kantojärvi, Antti Jussi Ämmälä, Nancy Yiu-Lin Yu, Hans Matsson, Jaana Nopola-Hemmi, Hasse Karlsson, Tiina Paunio, Torkel Klingberg, Eira Leinonen, Juha Kere Identification of NCAN as a candidate gene for developmental dyslexia Journal Article Scientific Reports, 7 (1), pp. 1–11, 2017, ISSN: 20452322. Abstract \| Links @article{Einarsdottir2017, title = {Identification of NCAN as a candidate gene for developmental dyslexia}, author = {Elisabet Einarsdottir and Myriam Peyrard-Janvid and Fahimeh Darki and Jetro J Tuulari and Harri Merisaari and Linnea Karlsson and Noora M Scheinin and Jani Saunavaara and Riitta Parkkola and Katri Kantojärvi and Antti Jussi Ämmälä and Nancy {Yiu-Lin Yu} and Hans Matsson and Jaana Nopola-Hemmi and Hasse Karlsson and Tiina Paunio and Torkel Klingberg and Eira Leinonen and Juha Kere}, doi = {10.1038/s41598-017-10175-7}, issn = {20452322}, year = {2017}, date = {2017-01-01}, journal = {Scientific Reports}, volume = {7}, number = {1}, pages = {1--11}, abstract = {A whole-genome linkage analysis in a Finnish pedigree of eight cases with developmental dyslexia (DD) revealed several regions shared by the affected individuals. Analysis of coding variants from two affected individuals identified rs146011974G textgreater A (Ala1039Thr), a rare variant within the NCAN gene co-segregating with DD in the pedigree. This variant prompted us to consider this gene as a putative candidate for DD. The RNA expression pattern of the NCAN gene in human tissues was highly correlated (R textgreater 0.8) with that of the previously suggested DD susceptibility genes KIAA0319, CTNND2, CNTNAP2 and GRIN2B. We investigated the association of common variation in NCAN to brain structures in two data sets: young adults (Brainchild study, Sweden) and infants (FinnBrain study, Finland). In young adults, we found associations between a common genetic variant in NCAN, rs1064395, and white matter volume in the left and right temporoparietal as well as the left inferior frontal brain regions. In infants, this same variant was found to be associated with cingulate and prefrontal grey matter volumes. Our results suggest NCAN as a new candidate gene for DD and indicate that NCAN variants affect brain structure.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close A whole-genome linkage analysis in a Finnish pedigree of eight cases with developmental dyslexia (DD) revealed several regions shared by the affected individuals. Analysis of coding variants from two affected individuals identified rs146011974G textgreater A (Ala1039Thr), a rare variant within the NCAN gene co-segregating with DD in the pedigree. This variant prompted us to consider this gene as a putative candidate for DD. The RNA expression pattern of the NCAN gene in human tissues was highly correlated (R textgreater 0.8) with that of the previously suggested DD susceptibility genes KIAA0319, CTNND2, CNTNAP2 and GRIN2B. We investigated the association of common variation in NCAN to brain structures in two data sets: young adults (Brainchild study, Sweden) and infants (FinnBrain study, Finland). In young adults, we found associations between a common genetic variant in NCAN, rs1064395, and white matter volume in the left and right temporoparietal as well as the left inferior frontal brain regions. In infants, this same variant was found to be associated with cingulate and prefrontal grey matter volumes. Our results suggest NCAN as a new candidate gene for DD and indicate that NCAN variants affect brain structure. Close doi:10.1038/s41598-017-10175-7 Close
	Annie Möller, Federico Nemmi, Kim Karlsson, Torkel Klingberg Transcranial Electric Stimulation Can Impair Gains during Working Memory Training and Affects the Resting State Connectivity Journal Article Frontiers in Human Neuroscience, 11 (July), pp. 1–12, 2017. Abstract \| Links @article{Moller2017, title = {Transcranial Electric Stimulation Can Impair Gains during Working Memory Training and Affects the Resting State Connectivity}, author = {Annie Möller and Federico Nemmi and Kim Karlsson and Torkel Klingberg}, doi = {10.3389/fnhum.2017.00364}, year = {2017}, date = {2017-01-01}, journal = {Frontiers in Human Neuroscience}, volume = {11}, number = {July}, pages = {1--12}, abstract = {Transcranial electric stimulation (tES) is a promising technique that has been shown to improve working memory (WM) performance and enhance the effect of cognitive training. However, experimental set up and electrode placement are not always determined based on neurofunctional knowledge about WM, leading to inconsistent results. Additional research on the effects of tES grounded on neurofunctional evidence is therefore necessary. 60 young, healthy, volunteers, assigned to 6 different groups, participated in 5 days of stimulation or sham treatment. 25 of these subjects also participated in MRI acquisition. We performed 3 experiments: In the first one we evaluated tES using either direct current stimulation (tDCS) with bilateral stimulation of the frontal or parietal lobe; in the second one we used the same tDCS protocol with a different electrode placement (i.e. supraorbital cathode); in the third one we used alternating currents (tACS) of 35 Hz, applied bilaterally to either the frontal or parietal lobes. The behavioral outcome measure was the WM capacity (i.e. number of remembered spatial position) during the 5 days of training. In a subsample of subjects we evaluated the neural effects of tDCS by measuring resting state connectivity with functional MRI, before and after the 5 days of tDCS and visuo-spatial WM training. We found a significant impairment of WM training-related gains associated with parietal tACS and frontal tDCS. Five days of tDCS stimulation was also associated with significant change in resting state connectivity revealed by multivariate pattern analysis (MVPA). None of the stimulation paradigms resulted in improved WM performance or enhanced WM training gains. These results show that tES can have negative effects on cognitive plasticity and affect resting-state functional connectivity.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Transcranial electric stimulation (tES) is a promising technique that has been shown to improve working memory (WM) performance and enhance the effect of cognitive training. However, experimental set up and electrode placement are not always determined based on neurofunctional knowledge about WM, leading to inconsistent results. Additional research on the effects of tES grounded on neurofunctional evidence is therefore necessary. 60 young, healthy, volunteers, assigned to 6 different groups, participated in 5 days of stimulation or sham treatment. 25 of these subjects also participated in MRI acquisition. We performed 3 experiments: In the first one we evaluated tES using either direct current stimulation (tDCS) with bilateral stimulation of the frontal or parietal lobe; in the second one we used the same tDCS protocol with a different electrode placement (i.e. supraorbital cathode); in the third one we used alternating currents (tACS) of 35 Hz, applied bilaterally to either the frontal or parietal lobes. The behavioral outcome measure was the WM capacity (i.e. number of remembered spatial position) during the 5 days of training. In a subsample of subjects we evaluated the neural effects of tDCS by measuring resting state connectivity with functional MRI, before and after the 5 days of tDCS and visuo-spatial WM training. We found a significant impairment of WM training-related gains associated with parietal tACS and frontal tDCS. Five days of tDCS stimulation was also associated with significant change in resting state connectivity revealed by multivariate pattern analysis (MVPA). None of the stimulation paradigms resulted in improved WM performance or enhanced WM training gains. These results show that tES can have negative effects on cognitive plasticity and affect resting-state functional connectivity. Close doi:10.3389/fnhum.2017.00364 Close
	Douglas Sjöwall, Mattias Hertz, Torkel Klingberg No long-term effect of physical activity intervention on working memory or arithmetic in preadolescents Journal Article Frontiers in Psychology, 8 (AUG), pp. 1–10, 2017, ISSN: 16641078. Abstract \| Links @article{Sjowall2017, title = {No long-term effect of physical activity intervention on working memory or arithmetic in preadolescents}, author = {Douglas Sjöwall and Mattias Hertz and Torkel Klingberg}, doi = {10.3389/fpsyg.2017.01342}, issn = {16641078}, year = {2017}, date = {2017-01-01}, journal = {Frontiers in Psychology}, volume = {8}, number = {AUG}, pages = {1--10}, abstract = {We investigate if increased physical activity leads to enhanced working memory capacity and arithmetic performance, in a 2-year school-based intervention in preadolescent children (age 6-13). The active school (n = 228) increased physical activity (aimed at increasing cardiovascular fitness) from 2 to 5 days a week while the control school (n = 242) remained at 2 days. Twice a year, participants performed tests of arithmetic as well as verbal and spatial working memory. They also rated stress with a questionnaire at the start and at the end of the intervention. There was no beneficial development of working memory or arithmetic for the active school as compared to the control school. Furthermore, subgroup analyses revealed no favorable intervention effect for high/low baseline fitness, cognition or grit. Unexpectedly, a significant increase in self-rated stress was detected for the active school and this effect was driven by girls rather than boys and by the younger rather than older children. These results indicate that longtime high intensity physical activity does not lead to a beneficial development of working memory or arithmetic in preadolescent children.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close We investigate if increased physical activity leads to enhanced working memory capacity and arithmetic performance, in a 2-year school-based intervention in preadolescent children (age 6-13). The active school (n = 228) increased physical activity (aimed at increasing cardiovascular fitness) from 2 to 5 days a week while the control school (n = 242) remained at 2 days. Twice a year, participants performed tests of arithmetic as well as verbal and spatial working memory. They also rated stress with a questionnaire at the start and at the end of the intervention. There was no beneficial development of working memory or arithmetic for the active school as compared to the control school. Furthermore, subgroup analyses revealed no favorable intervention effect for high/low baseline fitness, cognition or grit. Unexpectedly, a significant increase in self-rated stress was detected for the active school and this effect was driven by girls rather than boys and by the younger rather than older children. These results indicate that longtime high intensity physical activity does not lead to a beneficial development of working memory or arithmetic in preadolescent children. Close doi:10.3389/fpsyg.2017.01342 Close
	Henrik Ullman, Torkel Klingberg Timing of white matter development determines cognitive abilities at school entry but not in late adolescence Journal Article Cerebral Cortex, 27 (9), pp. 4516–4522, 2017, ISSN: 14602199. Abstract \| Links @article{Ullman2017, title = {Timing of white matter development determines cognitive abilities at school entry but not in late adolescence}, author = {Henrik Ullman and Torkel Klingberg}, doi = {10.1093/cercor/bhw256}, issn = {14602199}, year = {2017}, date = {2017-01-01}, journal = {Cerebral Cortex}, volume = {27}, number = {9}, pages = {4516--4522}, abstract = {The primary aim of this study was to investigate to what degree the age-related white matter development, here called " brain age " , is associated with working memory (WM) and numeric abilities in 6-year-old children. We measured white matter development using diffusion tensor imaging to calculate fractional anisotropy (FA). A " brain age " model was created using multivariate statistics, which described association between FA and age in a sample of 6-to 20-year-old children. This age model was then applied to predict " brain age " in a second sample of 6-year-old children. The predicted brain age correlated with WM performance and numerical ability (NA) (P textless 0.01, P textless 0.05) in the 6-year-old children. More than 50% of the stable variance in WM performance was explained. We found that in children older than 13 years of age, this association between brain age and WM was no longer significant (P textgreater 0.5). The results bear theoretical implications as they suggest that the variability in individual developmental timing strongly affects WM and NA at school start but badly predicts adolescent cognitive functioning. Furthermore, it bears practical implications as one may differentiate maturation lags from persistent low cognitive abilities in school children, complementing cognitive tests.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The primary aim of this study was to investigate to what degree the age-related white matter development, here called " brain age " , is associated with working memory (WM) and numeric abilities in 6-year-old children. We measured white matter development using diffusion tensor imaging to calculate fractional anisotropy (FA). A " brain age " model was created using multivariate statistics, which described association between FA and age in a sample of 6-to 20-year-old children. This age model was then applied to predict " brain age " in a second sample of 6-year-old children. The predicted brain age correlated with WM performance and numerical ability (NA) (P textless 0.01, P textless 0.05) in the 6-year-old children. More than 50% of the stable variance in WM performance was explained. We found that in children older than 13 years of age, this association between brain age and WM was no longer significant (P textgreater 0.5). The results bear theoretical implications as they suggest that the variability in individual developmental timing strongly affects WM and NA at school start but badly predicts adolescent cognitive functioning. Furthermore, it bears practical implications as one may differentiate maturation lags from persistent low cognitive abilities in school children, complementing cognitive tests. Close doi:10.1093/cercor/bhw256 Close
2016
	Margot A Schel, Torkel Klingberg Specialization of the Right Intraparietal Sulcus for Processing Mathematics During Development Journal Article Cerebral Cortex, 27 (9), pp. 4436–4446, 2016, ISSN: 1047-3211. Abstract \| Links @article{Schel2017, title = {Specialization of the Right Intraparietal Sulcus for Processing Mathematics During Development}, author = {Margot A Schel and Torkel Klingberg}, url = {http://cercor.oxfordjournals.org/cgi/doi/10.1093/cercor/bhw246}, doi = {10.1093/cercor/bhw246}, issn = {1047-3211}, year = {2016}, date = {2016-08-01}, journal = {Cerebral Cortex}, volume = {27}, number = {9}, pages = {4436--4446}, abstract = {Mathematical ability, especially perception of numbers and performance of arithmetics, is known to rely on the activation of intraparietal sulcus (IPS). However, reasoning ability and working memory, 2 highly associated abilities also activate partly overlapping regions. Most studies aimed at localizing mathematical function have used group averages, where individual variability is averaged out, thus confounding the anatomical specificity when localizing cognitive functions. Here, we analyze the functional anatomy of the intraparietal cortex by using individual analysis of subregions of IPS based on how they are structurally connected to frontal, parietal, and occipital cortex. Analysis of cortical thickness showed that the right anterior IPS, defined by its connections to the frontal lobe, was associated with both visuospatial working memory, and mathematics in 6-year-old children. This region specialized during development to be specifically related to mathematics, but not visuospatial working memory in adolescents and adults. This could be an example of interactive specialization, where interacting with the environment in combination with interactions between cortical regions leads from a more general role of right anterior IPS in spatial processing, to a specialization of this region for mathematics.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Mathematical ability, especially perception of numbers and performance of arithmetics, is known to rely on the activation of intraparietal sulcus (IPS). However, reasoning ability and working memory, 2 highly associated abilities also activate partly overlapping regions. Most studies aimed at localizing mathematical function have used group averages, where individual variability is averaged out, thus confounding the anatomical specificity when localizing cognitive functions. Here, we analyze the functional anatomy of the intraparietal cortex by using individual analysis of subregions of IPS based on how they are structurally connected to frontal, parietal, and occipital cortex. Analysis of cortical thickness showed that the right anterior IPS, defined by its connections to the frontal lobe, was associated with both visuospatial working memory, and mathematics in 6-year-old children. This region specialized during development to be specifically related to mathematics, but not visuospatial working memory in adolescents and adults. This could be an example of interactive specialization, where interacting with the environment in combination with interactions between cortical regions leads from a more general role of right anterior IPS in spatial processing, to a specialization of this region for mathematics. Close http://cercor.oxfordjournals.org/cgi/doi/10.1093/cercor/bhw246 doi:10.1093/cercor/bhw246 Close
	Federico Nemmi, Elin Helander, Ola Helenius, Rita Almeida, Martin Hassler, Pekka Räsänen, Torkel Klingberg Behavior and neuroimaging at baseline predict individual response to combined mathematical and working memory training in children Journal Article Developmental Cognitive Neuroscience, 20 , pp. 43–51, 2016, ISSN: 18789293. Abstract \| Links @article{Nemmi2016, title = {Behavior and neuroimaging at baseline predict individual response to combined mathematical and working memory training in children}, author = {Federico Nemmi and Elin Helander and Ola Helenius and Rita Almeida and Martin Hassler and Pekka Räsänen and Torkel Klingberg}, url = {http://dx.doi.org/10.1016/j.dcn.2016.06.004 https://linkinghub.elsevier.com/retrieve/pii/S1878929316300500}, doi = {10.1016/j.dcn.2016.06.004}, issn = {18789293}, year = {2016}, date = {2016-08-01}, journal = {Developmental Cognitive Neuroscience}, volume = {20}, pages = {43--51}, publisher = {Elsevier Ltd}, abstract = {Mathematical performance is highly correlated with several general cognitive abilities, including working memory (WM) capacity. Here we investigated the effect of numerical training using a number-line (NLT), WM training (WMT), or the combination of the two on a composite score of mathematical ability. The aim was to investigate if the combination contributed to the outcome, and determine if baseline performance or neuroimaging predict the magnitude of improvement. We randomly assigned 308, 6-year-old children to WMT, NLT, WMT + NLT or a control intervention. Overall, there was a significant effect of NLT but not WMT. The WMT + NLT was the only group that improved significantly more than the controls, although the interaction NLTxWM was non-significant. Higher WM and maths performance predicted larger benefits for WMT and NLT, respectively. Neuroimaging at baseline also contributed significant information about training gain. Different individuals showed as much as a three-fold difference in their responses to the same intervention. These results show that the impact of an intervention is highly dependent on individual characteristics of the child. If differences in responses could be used to optimize the intervention for each child, future interventions could be substantially more effective.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Mathematical performance is highly correlated with several general cognitive abilities, including working memory (WM) capacity. Here we investigated the effect of numerical training using a number-line (NLT), WM training (WMT), or the combination of the two on a composite score of mathematical ability. The aim was to investigate if the combination contributed to the outcome, and determine if baseline performance or neuroimaging predict the magnitude of improvement. We randomly assigned 308, 6-year-old children to WMT, NLT, WMT + NLT or a control intervention. Overall, there was a significant effect of NLT but not WMT. The WMT + NLT was the only group that improved significantly more than the controls, although the interaction NLTxWM was non-significant. Higher WM and maths performance predicted larger benefits for WMT and NLT, respectively. Neuroimaging at baseline also contributed significant information about training gain. Different individuals showed as much as a three-fold difference in their responses to the same intervention. These results show that the impact of an intervention is highly dependent on individual characteristics of the child. If differences in responses could be used to optimize the intervention for each child, future interventions could be substantially more effective. Close http://dx.doi.org/10.1016/j.dcn.2016.06.004 https://linkinghub.elsevier.com/retr[...] doi:10.1016/j.dcn.2016.06.004 Close
	Christos Constantinidis, Torkel Klingberg The neuroscience of working memory capacity and training Journal Article Nature Reviews Neuroscience, 17 (7), pp. 438–449, 2016, ISSN: 1471-003X. Abstract \| Links @article{Constantinidis2016, title = {The neuroscience of working memory capacity and training}, author = {Christos Constantinidis and Torkel Klingberg}, url = {http://dx.doi.org/10.1038/nrn.2016.43 http://www.nature.com/articles/nrn.2016.43}, doi = {10.1038/nrn.2016.43}, issn = {1471-003X}, year = {2016}, date = {2016-07-01}, journal = {Nature Reviews Neuroscience}, volume = {17}, number = {7}, pages = {438--449}, publisher = {Nature Publishing Group}, abstract = {Working memory (WM) — the ability to maintain and manipulate information over a period of seconds — is a key cognitive skill. Constantinidis and Klingberg discuss non-human-primate, computational-modelling and human-neuroimaging studies that examine the neural bases of WM and training-induced enhancements of WM capacity.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Working memory (WM) — the ability to maintain and manipulate information over a period of seconds — is a key cognitive skill. Constantinidis and Klingberg discuss non-human-primate, computational-modelling and human-neuroimaging studies that examine the neural bases of WM and training-induced enhancements of WM capacity. Close http://dx.doi.org/10.1038/nrn.2016.43 http://www.nature.com/articles/nrn.2016.43 doi:10.1038/nrn.2016.43 Close
	Fahimeh Darki, Federico Nemmi, Annie Möller, Rouslan Sitnikov, Torkel Klingberg Quantitative susceptibility mapping of striatum in children and adults, and its association with working memory performance Journal Article NeuroImage, 136 , pp. 208–214, 2016, ISSN: 10959572. Abstract \| Links @article{Darki2016, title = {Quantitative susceptibility mapping of striatum in children and adults, and its association with working memory performance}, author = {Fahimeh Darki and Federico Nemmi and Annie Möller and Rouslan Sitnikov and Torkel Klingberg}, url = {http://dx.doi.org/10.1016/j.neuroimage.2016.04.065}, doi = {10.1016/j.neuroimage.2016.04.065}, issn = {10959572}, year = {2016}, date = {2016-01-01}, journal = {NeuroImage}, volume = {136}, pages = {208--214}, publisher = {Elsevier Inc.}, abstract = {Quantitative susceptibility mapping (QSM) is a magnetic resonance imaging (MRI) technique in which the magnetic susceptibility characteristic of molecular and cellular components, including iron and myelin, is quantified. Rapid iron accumulation in subcortical nuclei and myelination of the white matter tracts are two important developmental processes that contribute to cognitive functions. Both also contribute to the magnetic susceptibility of the brain tissues. Here, we used the QSM as indirect measures of iron in subcortical nuclei and myelin in caudo-frontal white matter pathways. We included two groups of participants; 21 children aged 6-7 years and 25 adults aged 21-40 years. All subjects also performed tests estimating their visuo-spatial working memory capacity.Adults had higher magnetic susceptibility in all subcortical nuclei, compared to children. The magnetic susceptibility of these nuclei highly correlated with their previously reported iron content. Moreover, working memory performance correlated significantly with the magnetic susceptibility in caudate nucleus in both children and adults, while the correlation was not significant for gray matter density. QSM of white matter in the caudo-frontal tract also differed between children and adults, but did not correlate with working memory scores. These results indicate that QSM is a feasible technique to measure developmental aspects of changes in the striatum, possibly related to iron content that is relevant to cognition.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Quantitative susceptibility mapping (QSM) is a magnetic resonance imaging (MRI) technique in which the magnetic susceptibility characteristic of molecular and cellular components, including iron and myelin, is quantified. Rapid iron accumulation in subcortical nuclei and myelination of the white matter tracts are two important developmental processes that contribute to cognitive functions. Both also contribute to the magnetic susceptibility of the brain tissues. Here, we used the QSM as indirect measures of iron in subcortical nuclei and myelin in caudo-frontal white matter pathways. We included two groups of participants; 21 children aged 6-7 years and 25 adults aged 21-40 years. All subjects also performed tests estimating their visuo-spatial working memory capacity.Adults had higher magnetic susceptibility in all subcortical nuclei, compared to children. The magnetic susceptibility of these nuclei highly correlated with their previously reported iron content. Moreover, working memory performance correlated significantly with the magnetic susceptibility in caudate nucleus in both children and adults, while the correlation was not significant for gray matter density. QSM of white matter in the caudo-frontal tract also differed between children and adults, but did not correlate with working memory scores. These results indicate that QSM is a feasible technique to measure developmental aspects of changes in the striatum, possibly related to iron content that is relevant to cognition. Close http://dx.doi.org/10.1016/j.neuroimage.2016.04.065 doi:10.1016/j.neuroimage.2016.04.065 Close
	Torkel Klingberg Neural basis of cognitive training and development Journal Article Current Opinion in Behavioral Sciences, 10 (i), pp. 97–101, 2016, ISSN: 23521546. Abstract \| Links @article{Klingberg2016, title = {Neural basis of cognitive training and development}, author = {Torkel Klingberg}, url = {http://dx.doi.org/10.1016/j.cobeha.2016.05.003}, doi = {10.1016/j.cobeha.2016.05.003}, issn = {23521546}, year = {2016}, date = {2016-01-01}, journal = {Current Opinion in Behavioral Sciences}, volume = {10}, number = {i}, pages = {97--101}, publisher = {Elsevier Ltd}, abstract = {This paper gives a brief overview of phases in brain development and discusses the hypothesis that mechanisms of working memory development are partly the same as those of working memory training. Brain development could be related to different, but overlapping phases: (i) structural maturation, with a relatively high reliance of preprogrammed processes; (ii) interactive specialization, which is a reorganization of the functional networks, partly in response to the environmental demands; (iii) training or skill learning, which is a qualitative change, such as strengthened connectivity of existent networks. The mechanisms of this skill learning could be similar to those neural processes observed during controlled studies of working memory training, where strengthened connectivity between frontal and parietal regions is suggested to play a central role. Education and formal schooling could be one important factor driving the training and skill-learning phase of executive functions, including improvement of working memory.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close This paper gives a brief overview of phases in brain development and discusses the hypothesis that mechanisms of working memory development are partly the same as those of working memory training. Brain development could be related to different, but overlapping phases: (i) structural maturation, with a relatively high reliance of preprogrammed processes; (ii) interactive specialization, which is a reorganization of the functional networks, partly in response to the environmental demands; (iii) training or skill learning, which is a qualitative change, such as strengthened connectivity of existent networks. The mechanisms of this skill learning could be similar to those neural processes observed during controlled studies of working memory training, where strengthened connectivity between frontal and parietal regions is suggested to play a central role. Education and formal schooling could be one important factor driving the training and skill-learning phase of executive functions, including improvement of working memory. Close http://dx.doi.org/10.1016/j.cobeha.2016.05.003 doi:10.1016/j.cobeha.2016.05.003 Close
2015
	Fahimeh Darki, Torkel Klingberg The role of fronto-parietal and fronto-striatal networks in the development of working memory: A longitudinal study Journal Article Cerebral Cortex, 25 (6), pp. 1587–1595, 2015, ISSN: 14602199. Abstract \| Links @article{Darki2015, title = {The role of fronto-parietal and fronto-striatal networks in the development of working memory: A longitudinal study}, author = {Fahimeh Darki and Torkel Klingberg}, url = {https://academic.oup.com/cercor/article-lookup/doi/10.1093/cercor/bht352}, doi = {10.1093/cercor/bht352}, issn = {14602199}, year = {2015}, date = {2015-06-01}, journal = {Cerebral Cortex}, volume = {25}, number = {6}, pages = {1587--1595}, abstract = {The increase in working memory (WM) capacity is an important part of cognitive development during childhood and adolescence. Cross-sectional analyses have associated this development with higher activity, thinner cortex, and white matter maturation in fronto-parietal networks. However, there is still a lack of longitudinal data showing the dynamics of this development and the role of subcortical structures. We included 89 individuals, aged 6-25 years, who were scanned 1-3 times at 2-year intervals. Functional magnetic resonance imaging (fMRI) was used to identify activated areas in superior frontal, intraparietal cortices, and caudate nucleus during performance on a visuo-spatial WM task. Probabilistic tractography determined the anatomical pathways between these regions. In the cross-sectional analysis, WM capacity correlated with activity in frontal and parietal regions, cortical thickness in parietal cortex, and white matter structure [both fractional anisotropy (FA) and white matter volume] of fronto-parietal and fronto-striatal tracts. However, in the longitudinal analysis, FA in white matter tracts and activity in caudate predicted future WM capacity. The results show a dynamic of neural networks underlying WM development in which cortical activity and structure relate to current capacity, while white matter tracts and caudate activity predict future WM capacity.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The increase in working memory (WM) capacity is an important part of cognitive development during childhood and adolescence. Cross-sectional analyses have associated this development with higher activity, thinner cortex, and white matter maturation in fronto-parietal networks. However, there is still a lack of longitudinal data showing the dynamics of this development and the role of subcortical structures. We included 89 individuals, aged 6-25 years, who were scanned 1-3 times at 2-year intervals. Functional magnetic resonance imaging (fMRI) was used to identify activated areas in superior frontal, intraparietal cortices, and caudate nucleus during performance on a visuo-spatial WM task. Probabilistic tractography determined the anatomical pathways between these regions. In the cross-sectional analysis, WM capacity correlated with activity in frontal and parietal regions, cortical thickness in parietal cortex, and white matter structure [both fractional anisotropy (FA) and white matter volume] of fronto-parietal and fronto-striatal tracts. However, in the longitudinal analysis, FA in white matter tracts and activity in caudate predicted future WM capacity. The results show a dynamic of neural networks underlying WM development in which cortical activity and structure relate to current capacity, while white matter tracts and caudate activity predict future WM capacity. Close https://academic.oup.com/cercor/article-lookup/doi/10.1093/cercor/bht352 doi:10.1093/cercor/bht352 Close
	Megan Spencer-Smith, Torkel Klingberg Benefits of a working memory training program for inattention in daily life: A systematic review and meta-analysis Journal Article PLoS ONE, 10 (3), pp. 1–18, 2015, ISSN: 19326203. Abstract \| Links @article{Spencer-Smith2015, title = {Benefits of a working memory training program for inattention in daily life: A systematic review and meta-analysis}, author = {Megan Spencer-Smith and Torkel Klingberg}, doi = {10.1371/journal.pone.0119522}, issn = {19326203}, year = {2015}, date = {2015-01-01}, journal = {PLoS ONE}, volume = {10}, number = {3}, pages = {1--18}, abstract = {BACKGROUND: Many common disorders across the lifespan feature impaired working memory (WM). Reported benefits of a WM training program include improving inattention in daily life, but this has not been evaluated in a meta-analysis. This study aimed to evaluate whether one WM training method has benefits for inattention in daily life by conducting a systematic review and meta-analysis. METHODS: We searched Medline and PsycINFO, relevant journals and contacted authors for studies with an intervention and control group reporting post-training estimates of inattention in daily life. To reduce the influence of different WM training methods on the findings, the review was restricted to trials evaluating the Cogmed method. A meta-analysis calculated the pooled standardised difference in means (SMD) between intervention and control groups. RESULTS: A total of 622 studies were identified and 12 studies with 13 group comparisons met inclusion criteria. The meta-analysis showed a significant training effect on inattention in daily life}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close BACKGROUND: Many common disorders across the lifespan feature impaired working memory (WM). Reported benefits of a WM training program include improving inattention in daily life, but this has not been evaluated in a meta-analysis. This study aimed to evaluate whether one WM training method has benefits for inattention in daily life by conducting a systematic review and meta-analysis. METHODS: We searched Medline and PsycINFO, relevant journals and contacted authors for studies with an intervention and control group reporting post-training estimates of inattention in daily life. To reduce the influence of different WM training methods on the findings, the review was restricted to trials evaluating the Cogmed method. A meta-analysis calculated the pooled standardised difference in means (SMD) between intervention and control groups. RESULTS: A total of 622 studies were identified and 12 studies with 13 group comparisons met inclusion criteria. The meta-analysis showed a significant training effect on inattention in daily life Close doi:10.1371/journal.pone.0119522 Close
	Henrik Ullman, Megan Spencer-Smith, Deanne K Thompson, Lex W Doyle, Terrie E Inder, Peter J Anderson, Torkel Klingberg Neonatal MRI is associated with future cognition and academic achievement in preterm children Journal Article Brain, 138 (11), pp. 3251–3262, 2015, ISSN: 14602156. Abstract \| Links @article{Ullman2015, title = {Neonatal MRI is associated with future cognition and academic achievement in preterm children}, author = {Henrik Ullman and Megan Spencer-Smith and Deanne K Thompson and Lex W Doyle and Terrie E Inder and Peter J Anderson and Torkel Klingberg}, doi = {10.1093/brain/awv244}, issn = {14602156}, year = {2015}, date = {2015-01-01}, journal = {Brain}, volume = {138}, number = {11}, pages = {3251--3262}, abstract = {textcopyright 2015 The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com. School-age children born preterm are particularly at risk for low mathematical achievement, associated with reduced working memory and number skills. Early identification of preterm children at risk for future impairments using brain markers might assist in referral for early intervention. This study aimed to examine the use of neonatal magnetic resonance imaging measures derived from automated methods (Jacobian maps from deformation-based morphometry; fractional anisotropy maps from diffusion tensor images) to predict skills important for mathematical achievement (working memory, early mathematical skills) at 5 and 7 years in a cohort of preterm children using both univariable (general linear model) and multivariable models (support vector regression). Participants were preterm children born textless30 weeks' gestational age and healthy control children born ≥37 weeks' gestational age at the Royal Women's Hospital in Melbourne, Australia between July 2001 and December 2003 and recruited into a prospective longitudinal cohort study. At term-equivalent age (±2 weeks) 224 preterm and 46 control infants were recruited for magnetic resonance imaging. Working memory and early mathematics skills were assessed at 5 years (n = 195 preterm; n = 40 controls) and 7 years (n = 197 preterm; n = 43 controls). In the preterm group, results identified localized regions around the insula and putamen in the neonatal Jacobian map that were positively associated with early mathematics at 5 and 7 years (both P textless 0.05), even after covarying for important perinatal clinical factors using general linear model but not support vector regression. The neonatal Jacobian map showed the same trend for association with working memory at 7 years (models ranging from P = 0.07 to P = 0.05). Neonatal fractional anisotropy was positively associated with working memory and early mathematics at 5 years (both P textless 0.001) even after covarying for clinical factors using support vector regression but not general linear model. These significant relationships were not observed in the control group. In summary, we identified, in the preterm brain, regions around the insula and putamen using neonatal deformation-based morphometry, and brain microstructural organization using neonatal diffusion tensor imaging, associated with skills important for childhood mathematical achievement. Results contribute to the growing evidence for the clinical utility of neonatal magnetic resonance imaging for early identification of preterm infants at risk for childhood cognitive and academic impairment.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close textcopyright 2015 The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com. School-age children born preterm are particularly at risk for low mathematical achievement, associated with reduced working memory and number skills. Early identification of preterm children at risk for future impairments using brain markers might assist in referral for early intervention. This study aimed to examine the use of neonatal magnetic resonance imaging measures derived from automated methods (Jacobian maps from deformation-based morphometry; fractional anisotropy maps from diffusion tensor images) to predict skills important for mathematical achievement (working memory, early mathematical skills) at 5 and 7 years in a cohort of preterm children using both univariable (general linear model) and multivariable models (support vector regression). Participants were preterm children born textless30 weeks' gestational age and healthy control children born ≥37 weeks' gestational age at the Royal Women's Hospital in Melbourne, Australia between July 2001 and December 2003 and recruited into a prospective longitudinal cohort study. At term-equivalent age (±2 weeks) 224 preterm and 46 control infants were recruited for magnetic resonance imaging. Working memory and early mathematics skills were assessed at 5 years (n = 195 preterm; n = 40 controls) and 7 years (n = 197 preterm; n = 43 controls). In the preterm group, results identified localized regions around the insula and putamen in the neonatal Jacobian map that were positively associated with early mathematics at 5 and 7 years (both P textless 0.05), even after covarying for important perinatal clinical factors using general linear model but not support vector regression. The neonatal Jacobian map showed the same trend for association with working memory at 7 years (models ranging from P = 0.07 to P = 0.05). Neonatal fractional anisotropy was positively associated with working memory and early mathematics at 5 years (both P textless 0.001) even after covarying for clinical factors using support vector regression but not general linear model. These significant relationships were not observed in the control group. In summary, we identified, in the preterm brain, regions around the insula and putamen using neonatal deformation-based morphometry, and brain microstructural organization using neonatal diffusion tensor imaging, associated with skills important for childhood mathematical achievement. Results contribute to the growing evidence for the clinical utility of neonatal magnetic resonance imaging for early identification of preterm infants at risk for childhood cognitive and academic impairment. Close doi:10.1093/brain/awv244 Close
2014
	Sissela Bergman-Nutley, Torkel Klingberg Effect of working memory training on working memory, arithmetic and following instructions Journal Article Psychological Research, 78 (6), pp. 869–877, 2014, ISSN: 0340-0727. Abstract \| Links @article{Bergman-Nutley2014, title = {Effect of working memory training on working memory, arithmetic and following instructions}, author = {Sissela Bergman-Nutley and Torkel Klingberg}, url = {http://link.springer.com/10.1007/s00426-014-0614-0}, doi = {10.1007/s00426-014-0614-0}, issn = {0340-0727}, year = {2014}, date = {2014-11-01}, journal = {Psychological Research}, volume = {78}, number = {6}, pages = {869--877}, abstract = {Abstract Mathematical ability is dependent on specific mathematical training but also associated with a range of cognitive factors, including working memory (WM) capacity. Previous studies have shown that WM training leads to improvement in non-trained WM tasks, but the results regarding transfer to mathematics are inconclusive. In the present study, 176 children with WM deficits, aged 7–15 years performed 5 weeks ofWMtraining. During the training period, they were assessed five times with a test of complex WM (the Odd One Out), a test of remembering and following instructions and a test of arithmetic. The improvements were compared to the performance of a control group of 304 typically developing children aged 7–15 years who performed the same transfer tasks at the same time intervals, but without training. The training group improved significantly more than the control group on all three transfer tests (all p$backslash$0.0001), after correction for baseline performance, age and sex. The effect size for mathematics was small and the effect sizes for the WM tasks were moderate to large. The transfer increased line- arly with the amount of training time and correlated with the amount of improvement on the trained tasks. These results confirm previous findings of training-induced improvements in non-trained WM tasks including the ability to follow instructions, but extend previous findings by showing improvements also for arithmetic. This is encouraging regarding the potential role of cognitive training for education, but it is desirable to find paradigms that would enhance the effect of the training on mathe- matics. One of the future challenges for studying training effects is combining large sample sizes with high quality and compliance, to detect relevant but smaller effects of cognitive training.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Abstract Mathematical ability is dependent on specific mathematical training but also associated with a range of cognitive factors, including working memory (WM) capacity. Previous studies have shown that WM training leads to improvement in non-trained WM tasks, but the results regarding transfer to mathematics are inconclusive. In the present study, 176 children with WM deficits, aged 7–15 years performed 5 weeks ofWMtraining. During the training period, they were assessed five times with a test of complex WM (the Odd One Out), a test of remembering and following instructions and a test of arithmetic. The improvements were compared to the performance of a control group of 304 typically developing children aged 7–15 years who performed the same transfer tasks at the same time intervals, but without training. The training group improved significantly more than the control group on all three transfer tests (all p$backslash$0.0001), after correction for baseline performance, age and sex. The effect size for mathematics was small and the effect sizes for the WM tasks were moderate to large. The transfer increased line- arly with the amount of training time and correlated with the amount of improvement on the trained tasks. These results confirm previous findings of training-induced improvements in non-trained WM tasks including the ability to follow instructions, but extend previous findings by showing improvements also for arithmetic. This is encouraging regarding the potential role of cognitive training for education, but it is desirable to find paradigms that would enhance the effect of the training on mathe- matics. One of the future challenges for studying training effects is combining large sample sizes with high quality and compliance, to detect relevant but smaller effects of cognitive training. Close http://link.springer.com/10.1007/s00426-014-0614-0 doi:10.1007/s00426-014-0614-0 Close
	Torkel Klingberg Childhood cognitive development as a skill Journal Article Trends in Cognitive Sciences, 18 (11), pp. 573–579, 2014, ISSN: 13646613. Abstract \| Links @article{Klingberg2014, title = {Childhood cognitive development as a skill}, author = {Torkel Klingberg}, url = {http://dx.doi.org/10.1016/j.tics.2014.06.007 https://www.sciencedirect.com/science/article/pii/S1364661314001533 http://linkinghub.elsevier.com/retrieve/pii/S1364661314001533 https://linkinghub.elsevier.com/retrieve/pii/S1364661314001533}, doi = {10.1016/j.tics.2014.06.007}, issn = {13646613}, year = {2014}, date = {2014-11-01}, journal = {Trends in Cognitive Sciences}, volume = {18}, number = {11}, pages = {573--579}, publisher = {Elsevier Current Trends}, abstract = {Theories view childhood development as being either driven by structural maturation of the brain or being driven by skill-learning. It is hypothesized here that working memory (WM) development during childhood is partly driven by training effects in the environment, and that similar neural mechanisms underlie training-induced plasticity and childhood development. In particular, the functional connectivity of a fronto-parietal network is suggested to be associated with WM capacity. The striatum, dopamine receptor D2 (DRD2) activity, and corticostriatal white-matter tracts, on the other hand, seem to be more important for plasticity and change of WM capacity during both training and development. In this view, the development of WM capacity during childhood partly involves the same mechanisms as skill-learning.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Theories view childhood development as being either driven by structural maturation of the brain or being driven by skill-learning. It is hypothesized here that working memory (WM) development during childhood is partly driven by training effects in the environment, and that similar neural mechanisms underlie training-induced plasticity and childhood development. In particular, the functional connectivity of a fronto-parietal network is suggested to be associated with WM capacity. The striatum, dopamine receptor D2 (DRD2) activity, and corticostriatal white-matter tracts, on the other hand, seem to be more important for plasticity and change of WM capacity during both training and development. In this view, the development of WM capacity during childhood partly involves the same mechanisms as skill-learning. Close http://dx.doi.org/10.1016/j.tics.2014.06.007 https://www.sciencedirect.com/scien[...] doi:10.1016/j.tics.2014.06.007 Close
	Charlotte Nymberg, Tobias Banaschewski, Arun LW Bokde, Christian Büchel, Patricia Conrod, Herta Flor, Vincent Frouin, Hugh Garavan, P Gowland, Andreas Heinz, Bernd Ittermann, Karl Mann, Jean-Luc Martinot, Frauke Nees, Tomas Paus, Zdenka Pausova, Marcella Rietschel, Trevor W Robbins, Michael N Smolka, Andreas Ströhle, Gunter Schumann, Torkel Klingberg DRD2/ANKK1 Polymorphism Modulates the Effect of Ventral Striatal Activation on Working Memory Performance Journal Article Neuropsychopharmacology, 39 (10), pp. 2357–2365, 2014, ISSN: 0893-133X. Abstract \| Links @article{Nymberg2014, title = {DRD2/ANKK1 Polymorphism Modulates the Effect of Ventral Striatal Activation on Working Memory Performance}, author = {Charlotte Nymberg and Tobias Banaschewski and Arun LW Bokde and Christian Büchel and Patricia Conrod and Herta Flor and Vincent Frouin and Hugh Garavan and P Gowland and Andreas Heinz and Bernd Ittermann and Karl Mann and Jean-Luc Martinot and Frauke Nees and Tomas Paus and Zdenka Pausova and Marcella Rietschel and Trevor W Robbins and Michael N Smolka and Andreas Ströhle and Gunter Schumann and Torkel Klingberg}, url = {http://www.nature.com/articles/npp201483}, doi = {10.1038/npp.2014.83}, issn = {0893-133X}, year = {2014}, date = {2014-09-01}, journal = {Neuropsychopharmacology}, volume = {39}, number = {10}, pages = {2357--2365}, abstract = {Motivation is important for learning and cognition. Although dopaminergic (D2) transmission in the ventral striatum (VS) is associated with motivation, learning, and cognition are more strongly associated with function of the dorsal striatum, including activation in the caudate nucleus. A recent study found an interaction between intrinsic motivation and the DRD2/ANKK1 polymorphism (rs1800497), suggesting that A-carriers of rs1800497 are significantly more sensitive to motivation in order to improve during working memory (WM) training. Using data from the two large-scale imaging genetic data sets, IMAGEN (n=1080, age 13-15 years) and BrainChild (n∼300, age 6-27), we investigated whether rs1800497 is associated with WM. In the IMAGEN data set, we tested whether VS/caudate activation during reward anticipation was associated with WM performance and whether rs1800497 and VS/caudate activation interact to affect WM performance. We found that rs1800497 was associated with WM performance in IMAGEN and BrainChild. Higher VS and caudate activation during reward processing were significantly associated with higher WM performance (ptextless0.0001). An interaction was found between the DRD2/ANKK1 polymorphism rs1800497 and VS activation during reward anticipation on WM (ptextless0.01), such that carriers of the minor allele (A) showed a significant correlation between VS activation and WM, whereas the GG-homozygotes did not, suggesting that the effect of VS BOLD on WM is modified by inter-individual genetic differences related to D2 dopaminergic transmission. textcopyright 2014 American College of Neuropsychopharmacology.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Motivation is important for learning and cognition. Although dopaminergic (D2) transmission in the ventral striatum (VS) is associated with motivation, learning, and cognition are more strongly associated with function of the dorsal striatum, including activation in the caudate nucleus. A recent study found an interaction between intrinsic motivation and the DRD2/ANKK1 polymorphism (rs1800497), suggesting that A-carriers of rs1800497 are significantly more sensitive to motivation in order to improve during working memory (WM) training. Using data from the two large-scale imaging genetic data sets, IMAGEN (n=1080, age 13-15 years) and BrainChild (n∼300, age 6-27), we investigated whether rs1800497 is associated with WM. In the IMAGEN data set, we tested whether VS/caudate activation during reward anticipation was associated with WM performance and whether rs1800497 and VS/caudate activation interact to affect WM performance. We found that rs1800497 was associated with WM performance in IMAGEN and BrainChild. Higher VS and caudate activation during reward processing were significantly associated with higher WM performance (ptextless0.0001). An interaction was found between the DRD2/ANKK1 polymorphism rs1800497 and VS activation during reward anticipation on WM (ptextless0.01), such that carriers of the minor allele (A) showed a significant correlation between VS activation and WM, whereas the GG-homozygotes did not, suggesting that the effect of VS BOLD on WM is modified by inter-individual genetic differences related to D2 dopaminergic transmission. textcopyright 2014 American College of Neuropsychopharmacology. Close http://www.nature.com/articles/npp201483 doi:10.1038/npp.2014.83 Close
	H Ullman, R Almeida, Torkel Klingberg Structural Maturation and Brain Activity Predict Future Working Memory Capacity during Childhood Development Journal Article Journal of Neuroscience, 34 (5), pp. 1592–1598, 2014, ISSN: 0270-6474. Abstract \| Links @article{Ullman2014, title = {Structural Maturation and Brain Activity Predict Future Working Memory Capacity during Childhood Development}, author = {H Ullman and R Almeida and Torkel Klingberg}, url = {http://www.jneurosci.org/cgi/doi/10.1523/JNEUROSCI.0842-13.2014}, doi = {10.1523/JNEUROSCI.0842-13.2014}, issn = {0270-6474}, year = {2014}, date = {2014-01-01}, journal = {Journal of Neuroscience}, volume = {34}, number = {5}, pages = {1592--1598}, abstract = {Human working memory capacity develops during childhood and is a strong predictor of future academic performance, in particular, achievements in mathematics and reading. Predicting working memory development is important for the early identification of children at risk for poor cognitive and academic development. Here we show that structural and functional magnetic resonance imaging data explain variance in children's working memory capacity 2 years later, which was unique variance in addition to that predicted using cognitive tests. While current working memory capacity correlated with frontoparietal cortical activity, the future capacity could be inferred from structure and activity in basal ganglia and thalamus. This gives a novel insight into the neural mechanisms of childhood development and supports the idea that neuroimaging can have a unique role in predicting children's cognitive development.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Human working memory capacity develops during childhood and is a strong predictor of future academic performance, in particular, achievements in mathematics and reading. Predicting working memory development is important for the early identification of children at risk for poor cognitive and academic development. Here we show that structural and functional magnetic resonance imaging data explain variance in children's working memory capacity 2 years later, which was unique variance in addition to that predicted using cognitive tests. While current working memory capacity correlated with frontoparietal cortical activity, the future capacity could be inferred from structure and activity in basal ganglia and thalamus. This gives a novel insight into the neural mechanisms of childhood development and supports the idea that neuroimaging can have a unique role in predicting children's cognitive development. Close http://www.jneurosci.org/cgi/doi/10.1523/JNEUROSCI.0842-13.2014 doi:10.1523/JNEUROSCI.0842-13.2014 Close
	F Darki, M Peyrard-Janvid, H Matsson, J Kere, T Klingberg DCDC2 Polymorphism Is Associated with Left Temporoparietal Gray and White Matter Structures during Development Journal Article Journal of Neuroscience, 34 (43), pp. 14455–14462, 2014, ISSN: 0270-6474. Abstract \| Links @article{Darki2014, title = {DCDC2 Polymorphism Is Associated with Left Temporoparietal Gray and White Matter Structures during Development}, author = {F Darki and M Peyrard-Janvid and H Matsson and J Kere and T Klingberg}, doi = {10.1523/jneurosci.1216-14.2014}, issn = {0270-6474}, year = {2014}, date = {2014-01-01}, journal = {Journal of Neuroscience}, volume = {34}, number = {43}, pages = {14455--14462}, abstract = {textcopyright 2014 the authors. Three genes, DYX1C1, DCDC2, and KIAA0319, have been previously associated with dyslexia, neuronal migration, and ciliary function. Three polymorphisms within these genes, rs3743204 (DYX1C1), rs793842 (DCDC2), and rs6935076 (KIAA0319) have also been linked to normal variability of left temporoparietal white matter volume connecting the middle temporal cortex to the angular and supramarginal gyri. Here, we assessed whether these polymorphisms are also related to the cortical thickness of the associated regions during childhood development using a longitudinal dataset of 76 randomly selected children and young adults who were scanned up to three times each, 2 years apart. rs793842 in DCDC2 was significantly associated with the thickness of left angular and supramarginal gyri as well as the left lateral occipital cortex. The cortex was significantly thicker for T-allele carriers, who also had lower white matter volume and lower reading comprehension scores. There was a negative correlation between white matter volume and cortical thickness, but only white matter volume predicted reading comprehension 2 years after scanning. These results show how normal variability in reading comprehension is related to gene, white matter volume, and cortical thickness in the inferior parietal lobe. Possibly, the variability of gray and white matter structures could both be related to the role of DCDC2 in ciliary function, which affects both neuronal migration and axonal outgrowth.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close textcopyright 2014 the authors. Three genes, DYX1C1, DCDC2, and KIAA0319, have been previously associated with dyslexia, neuronal migration, and ciliary function. Three polymorphisms within these genes, rs3743204 (DYX1C1), rs793842 (DCDC2), and rs6935076 (KIAA0319) have also been linked to normal variability of left temporoparietal white matter volume connecting the middle temporal cortex to the angular and supramarginal gyri. Here, we assessed whether these polymorphisms are also related to the cortical thickness of the associated regions during childhood development using a longitudinal dataset of 76 randomly selected children and young adults who were scanned up to three times each, 2 years apart. rs793842 in DCDC2 was significantly associated with the thickness of left angular and supramarginal gyri as well as the left lateral occipital cortex. The cortex was significantly thicker for T-allele carriers, who also had lower white matter volume and lower reading comprehension scores. There was a negative correlation between white matter volume and cortical thickness, but only white matter volume predicted reading comprehension 2 years after scanning. These results show how normal variability in reading comprehension is related to gene, white matter volume, and cortical thickness in the inferior parietal lobe. Possibly, the variability of gray and white matter structures could both be related to the role of DCDC2 in ciliary function, which affects both neuronal migration and axonal outgrowth. Close doi:10.1523/jneurosci.1216-14.2014 Close
	Sissela Bergman Nutley, Fahimeh Darki, Torkel Klingberg Music practice is associated with development of working memory during childhood and adolescence Journal Article Frontiers in Human Neuroscience, 7 (January), pp. 1–9, 2014. Abstract \| Links @article{BergmanNutley2014, title = {Music practice is associated with development of working memory during childhood and adolescence}, author = {Sissela {Bergman Nutley} and Fahimeh Darki and Torkel Klingberg}, doi = {10.3389/fnhum.2013.00926}, year = {2014}, date = {2014-01-01}, journal = {Frontiers in Human Neuroscience}, volume = {7}, number = {January}, pages = {1--9}, abstract = {Practicing a musical instrument is associated with cognitive benefits and structural brain changes in correlational and interventional trials; however, the effect of musical training on cognition during childhood is still unclear. In this longitudinal study of child development we analyzed the association between musical practice and performance on reasoning, processing speed and working memory (WM) during development. Subjects (n = 352) between the ages of 6 and 25 years participated in neuropsychological assessments and neuroimaging investigations (n = 64) on two or three occasions, 2 years apart. Mixed model regression showed that musical practice had an overall positive association with WM capacity (visuo-spatial WM}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Practicing a musical instrument is associated with cognitive benefits and structural brain changes in correlational and interventional trials; however, the effect of musical training on cognition during childhood is still unclear. In this longitudinal study of child development we analyzed the association between musical practice and performance on reasoning, processing speed and working memory (WM) during development. Subjects (n = 352) between the ages of 6 and 25 years participated in neuropsychological assessments and neuroimaging investigations (n = 64) on two or three occasions, 2 years apart. Mixed model regression showed that musical practice had an overall positive association with WM capacity (visuo-spatial WM Close doi:10.3389/fnhum.2013.00926 Close

88 entries « ‹ 1 of 2 › »

2023
	Julia Ericson, Torkel Klingberg A dual-process model for cognitive training Journal Article Science of Learning, 8 (1), pp. 12, 2023. Abstract \| Links @article{Ericson2023, title = {A dual-process model for cognitive training}, author = {Julia Ericson, Torkel Klingberg}, url = {https://www.nature.com/articles/s41539-023-00161-2}, doi = {https://doi.org/10.1038/s41539-023-00161-2}, year = {2023}, date = {2023-05-06}, journal = {Science of Learning}, volume = {8}, number = {1}, pages = {12}, abstract = {A key goal in cognitive training research is understanding whether cognitive training enhances general cognitive capacity or provides only task-specific improvements. Here, we developed a quantitative model for describing the temporal dynamics of these two processes. We analyzed data from 1300 children enrolled in an 8 week working memory training program that included 5 transfer test sessions. Factor analyses suggested two separate processes: an early task-specific improvement, accounting for 44% of the total increase, and a slower capacity improvement. A hidden Markov model was then applied to individual training data, revealing that the task-specific improvement plateaued on the third day of training on average. Thus, training is not only task specific or transferable but a combination of the two. The models provide methods for quantifying and separating these processes, which is crucial for studying the effects of cognitive training and relating these effects to neural correlates.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close A key goal in cognitive training research is understanding whether cognitive training enhances general cognitive capacity or provides only task-specific improvements. Here, we developed a quantitative model for describing the temporal dynamics of these two processes. We analyzed data from 1300 children enrolled in an 8 week working memory training program that included 5 transfer test sessions. Factor analyses suggested two separate processes: an early task-specific improvement, accounting for 44% of the total increase, and a slower capacity improvement. A hidden Markov model was then applied to individual training data, revealing that the task-specific improvement plateaued on the third day of training on average. Thus, training is not only task specific or transferable but a combination of the two. The models provide methods for quantifying and separating these processes, which is crucial for studying the effects of cognitive training and relating these effects to neural correlates. Close https://www.nature.com/articles/s41539-023-00161-2 doi:https://doi.org/10.1038/s41539-023-00161-2 Close
	Samson Nivins, Torkel Klingberg Effects of prenatal exposure to maternal diabetes mellitus on deep grey matter structures and attention deficit hyperactivity disorder symptoms in children Journal Article Acta paediatrica, 2023. Abstract \| Links @article{Nivins2023b, title = {Effects of prenatal exposure to maternal diabetes mellitus on deep grey matter structures and attention deficit hyperactivity disorder symptoms in children}, author = {Samson Nivins, Torkel Klingberg}, url = {https://onlinelibrary.wiley.com/doi/full/10.1111/apa.16756}, doi = {https://doi.org/10.1111/apa.16756}, year = {2023}, date = {2023-03-23}, journal = {Acta paediatrica}, abstract = {Aim: The neuronal mechanism linking the association between maternal diabetes mellitus (DM) and risk of attention deficit hyperactivity disorder (ADHD) symptoms and working memory deficits in children was investigated. Methods: A total of 6291 children (52% boys) born beyond 28 weeks of gestation were included and underwent brain magnetic resonance imaging scans at 9–10 years. Subcortical brain volumes were estimated from the T1-weighted images. ADHD symptoms were assessed using factorial analysis of the Child Behaviour Checklist completed by parents/caregivers. Working memory performance was assessed with the NIH Toolbox. Results: Compared to unexposed children, those exposed to DM (n = 422) had smaller (β = −0.15, p = 0.001) volumes of pooled deep grey matter (GM). Regional analysis revealed smaller volumes of the caudate nucleus, putamen, thalamus and cerebellum but not of hippocampus. They also had altered cortico-striatal white matter projection tracts. DM was not associated with working memory deficits or inattention, but with increased hyperactivity/impulsivity and Sluggish Cognitive Tempo symptoms in boys. This hyperactivity/impulsivity symptom in boys was partially mediated by smaller deep GM volume. Conclusion: Exposure to DM during pregnancy leads to altered deep GM development during late childhood in their offspring. This contributed to an increased risk of hyperactivity/impulsivity symptoms in boys.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Aim: The neuronal mechanism linking the association between maternal diabetes mellitus (DM) and risk of attention deficit hyperactivity disorder (ADHD) symptoms and working memory deficits in children was investigated. Methods: A total of 6291 children (52% boys) born beyond 28 weeks of gestation were included and underwent brain magnetic resonance imaging scans at 9–10 years. Subcortical brain volumes were estimated from the T1-weighted images. ADHD symptoms were assessed using factorial analysis of the Child Behaviour Checklist completed by parents/caregivers. Working memory performance was assessed with the NIH Toolbox. Results: Compared to unexposed children, those exposed to DM (n = 422) had smaller (β = −0.15, p = 0.001) volumes of pooled deep grey matter (GM). Regional analysis revealed smaller volumes of the caudate nucleus, putamen, thalamus and cerebellum but not of hippocampus. They also had altered cortico-striatal white matter projection tracts. DM was not associated with working memory deficits or inattention, but with increased hyperactivity/impulsivity and Sluggish Cognitive Tempo symptoms in boys. This hyperactivity/impulsivity symptom in boys was partially mediated by smaller deep GM volume. Conclusion: Exposure to DM during pregnancy leads to altered deep GM development during late childhood in their offspring. This contributed to an increased risk of hyperactivity/impulsivity symptoms in boys. Close https://onlinelibrary.wiley.com/doi/full/10.1111/apa.16756 doi:https://doi.org/10.1111/apa.16756 Close
2022
	Nicholas Judd, Bruno Sauce, Torkel Klingberg Schooling substantially improves intelligence, but neither lessens nor widens the impacts of socioeconomics and genetics Journal Article npj Science of Learning, 7 (1), pp. 33, 2022. Abstract \| Links @article{Judd2022, title = {Schooling substantially improves intelligence, but neither lessens nor widens the impacts of socioeconomics and genetics}, author = {Nicholas Judd, Bruno Sauce, Torkel Klingberg}, url = {https://www.nature.com/articles/s41539-022-00148-5}, doi = {https://doi.org/10.1038/s41539-022-00148-5}, year = {2022}, date = {2022-12-15}, journal = {npj Science of Learning}, volume = {7}, number = {1}, pages = {33}, abstract = {Schooling, socioeconomic status (SES), and genetics all impact intelligence. However, it is unclear to what extent their contributions are unique and if they interact. Here we used a multi-trait polygenic score for cognition (cogPGS) with a quasi-experimental regression discontinuity design to isolate how months of schooling relate to intelligence in 6567 children (aged 9–11). We found large, independent effects of schooling (β ~ 0.15), cogPGS (β ~ 0.10), and SES (β ~ 0.20) on working memory, crystallized (cIQ), and fluid intelligence (fIQ). Notably, two years of schooling had a larger effect on intelligence than the lifetime consequences, since birth, of SES or cogPGS-based inequalities. However, schooling showed no interaction with cogPGS or SES for the three intelligence domains tested. While schooling had strong main effects on intelligence, it did not lessen, nor widen the impact of these preexisting SES or genetic factors.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Schooling, socioeconomic status (SES), and genetics all impact intelligence. However, it is unclear to what extent their contributions are unique and if they interact. Here we used a multi-trait polygenic score for cognition (cogPGS) with a quasi-experimental regression discontinuity design to isolate how months of schooling relate to intelligence in 6567 children (aged 9–11). We found large, independent effects of schooling (β ~ 0.15), cogPGS (β ~ 0.10), and SES (β ~ 0.20) on working memory, crystallized (cIQ), and fluid intelligence (fIQ). Notably, two years of schooling had a larger effect on intelligence than the lifetime consequences, since birth, of SES or cogPGS-based inequalities. However, schooling showed no interaction with cogPGS or SES for the three intelligence domains tested. While schooling had strong main effects on intelligence, it did not lessen, nor widen the impact of these preexisting SES or genetic factors. Close https://www.nature.com/articles/s41539-022-00148-5 doi:https://doi.org/10.1038/s41539-022-00148-5 Close
	Da-Wei Zhang, Alexandros Moraidis, Torkel Klingberg Individually tuned theta HD-tACS improves spatial performance Journal Article Brain Stimulation, 15 (6), pp. 1439-1447, 2022. Abstract \| Links @article{Zhang2022, title = {Individually tuned theta HD-tACS improves spatial performance}, author = {Da-Wei Zhang, Alexandros Moraidis, Torkel Klingberg}, url = {https://www.sciencedirect.com/science/article/pii/S1935861X22002327}, doi = {https://doi.org/10.1016/j.brs.2022.10.009}, year = {2022}, date = {2022-11-01}, journal = {Brain Stimulation}, volume = {15}, number = {6}, pages = {1439-1447}, abstract = {Background Using transcranial alternating current stimulation (tACS) to improve visuospatial working memory (vsWM) has received considerable attention over the past few years. However, fundamental issues remain, such as the optimal frequency, the generality of behavioral effects, and the anatomical specificity of stimulation. Objectives Here we examined the effects of two theory-driven tACS protocols for improving vsWM on behavioral and electroencephalogram (EEG) measures. Methods Twenty adults each completed 3 HD-tACS conditions (Tuned, Slow, and Sham) on two separate days. The Tuned condition refers to a situation in which the frequency of tACS is tuned to individual theta peak measured during a vsWM task. By contrast, the frequency was fixed to 4 Hz in the Slow condition. A high-definition tACS was deployed to target smaller frontal and parietal regions for increasing their phase-locking values. During each tACS condition, participants performed vsWM, mental rotation (MR), and arithmetic tasks. Resting-state EEG (rs-EEG) was recorded before and after each condition. Results Compared with Sham, Tuned but not Slow improved both vsWM and MR but not arithmetics. The rs-EEG recording showed an increased fronto-parietal synchrony for Tuned, and this increase in synchronicity was correlated with the behavioral improvement. A follow-up study showed no behavioral improvement in Tuned with an anti-phase setting. Conclusion We provide the first evidence that simulating right fronto-parietal network with the tuned frequency increases the interregional synchronicity and improves performance on two spatial tasks. The results provide insight into the structure of spatial abilities as well as suggestions for stimulating the fronto-parietal network.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Background Using transcranial alternating current stimulation (tACS) to improve visuospatial working memory (vsWM) has received considerable attention over the past few years. However, fundamental issues remain, such as the optimal frequency, the generality of behavioral effects, and the anatomical specificity of stimulation. Objectives Here we examined the effects of two theory-driven tACS protocols for improving vsWM on behavioral and electroencephalogram (EEG) measures. Methods Twenty adults each completed 3 HD-tACS conditions (Tuned, Slow, and Sham) on two separate days. The Tuned condition refers to a situation in which the frequency of tACS is tuned to individual theta peak measured during a vsWM task. By contrast, the frequency was fixed to 4 Hz in the Slow condition. A high-definition tACS was deployed to target smaller frontal and parietal regions for increasing their phase-locking values. During each tACS condition, participants performed vsWM, mental rotation (MR), and arithmetic tasks. Resting-state EEG (rs-EEG) was recorded before and after each condition. Results Compared with Sham, Tuned but not Slow improved both vsWM and MR but not arithmetics. The rs-EEG recording showed an increased fronto-parietal synchrony for Tuned, and this increase in synchronicity was correlated with the behavioral improvement. A follow-up study showed no behavioral improvement in Tuned with an anti-phase setting. Conclusion We provide the first evidence that simulating right fronto-parietal network with the tuned frequency increases the interregional synchronicity and improves performance on two spatial tasks. The results provide insight into the structure of spatial abilities as well as suggestions for stimulating the fronto-parietal network. Close https://www.sciencedirect.com/science/article/pii/S1935861X22002327 doi:https://doi.org/10.1016/j.brs.2022.10.009 Close
	Da-Wei Zhang, Alexandros Moraidis, Torkel Klingberg Individually tuned theta HD-tACS improves spatial performance Journal Article Brain Stimulation, 15 (6), pp. 1439-1447, 2022. Abstract \| Links @article{Zhang2022b, title = {Individually tuned theta HD-tACS improves spatial performance}, author = {Da-Wei Zhang, Alexandros Moraidis, Torkel Klingberg}, url = {https://www.sciencedirect.com/science/article/pii/S1935861X22002327}, doi = {https://doi.org/10.1016/j.brs.2022.10.009}, year = {2022}, date = {2022-11-01}, journal = {Brain Stimulation}, volume = {15}, number = {6}, pages = {1439-1447}, abstract = {Background Using transcranial alternating current stimulation (tACS) to improve visuospatial working memory (vsWM) has received considerable attention over the past few years. However, fundamental issues remain, such as the optimal frequency, the generality of behavioral effects, and the anatomical specificity of stimulation. Objectives Here we examined the effects of two theory-driven tACS protocols for improving vsWM on behavioral and electroencephalogram (EEG) measures. Methods Twenty adults each completed 3 HD-tACS conditions (Tuned, Slow, and Sham) on two separate days. The Tuned condition refers to a situation in which the frequency of tACS is tuned to individual theta peak measured during a vsWM task. By contrast, the frequency was fixed to 4 Hz in the Slow condition. A high-definition tACS was deployed to target smaller frontal and parietal regions for increasing their phase-locking values. During each tACS condition, participants performed vsWM, mental rotation (MR), and arithmetic tasks. Resting-state EEG (rs-EEG) was recorded before and after each condition. Results Compared with Sham, Tuned but not Slow improved both vsWM and MR but not arithmetics. The rs-EEG recording showed an increased fronto-parietal synchrony for Tuned, and this increase in synchronicity was correlated with the behavioral improvement. A follow-up study showed no behavioral improvement in Tuned with an anti-phase setting. Conclusion We provide the first evidence that simulating right fronto-parietal network with the tuned frequency increases the interregional synchronicity and improves performance on two spatial tasks. The results provide insight into the structure of spatial abilities as well as suggestions for stimulating the fronto-parietal network.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Background Using transcranial alternating current stimulation (tACS) to improve visuospatial working memory (vsWM) has received considerable attention over the past few years. However, fundamental issues remain, such as the optimal frequency, the generality of behavioral effects, and the anatomical specificity of stimulation. Objectives Here we examined the effects of two theory-driven tACS protocols for improving vsWM on behavioral and electroencephalogram (EEG) measures. Methods Twenty adults each completed 3 HD-tACS conditions (Tuned, Slow, and Sham) on two separate days. The Tuned condition refers to a situation in which the frequency of tACS is tuned to individual theta peak measured during a vsWM task. By contrast, the frequency was fixed to 4 Hz in the Slow condition. A high-definition tACS was deployed to target smaller frontal and parietal regions for increasing their phase-locking values. During each tACS condition, participants performed vsWM, mental rotation (MR), and arithmetic tasks. Resting-state EEG (rs-EEG) was recorded before and after each condition. Results Compared with Sham, Tuned but not Slow improved both vsWM and MR but not arithmetics. The rs-EEG recording showed an increased fronto-parietal synchrony for Tuned, and this increase in synchronicity was correlated with the behavioral improvement. A follow-up study showed no behavioral improvement in Tuned with an anti-phase setting. Conclusion We provide the first evidence that simulating right fronto-parietal network with the tuned frequency increases the interregional synchronicity and improves performance on two spatial tasks. The results provide insight into the structure of spatial abilities as well as suggestions for stimulating the fronto-parietal network. Close https://www.sciencedirect.com/science/article/pii/S1935861X22002327 doi:https://doi.org/10.1016/j.brs.2022.10.009 Close
	Richard Scruggs, Jalal Nouri, Torkel Klingberg Using Knowledge Tracing to Predict Students’ Performance in Cognitive Training and Math Proceeding Springer International Publishing, 2022. Abstract \| Links @proceedings{Scruggs2022, title = {Using Knowledge Tracing to Predict Students’ Performance in Cognitive Training and Math}, author = {Richard Scruggs, Jalal Nouri, Torkel Klingberg}, url = {https://link.springer.com/chapter/10.1007/978-3-031-11647-6_81}, doi = {https://doi.org/10.1007/978-3-031-11647-6_81}, year = {2022}, date = {2022-07-06}, booktitle = {Artificial Intelligence in Education. Posters and Late Breaking Results, Workshops and Tutorials, Industry and Innovation Tracks, Practitioners’ and Doctoral Consortium: 23rd International Conference}, pages = {410-413}, publisher = {Springer International Publishing}, abstract = {Cognitive training aims to improve skills such as working memory capacity and spatial ability, which have been linked to math skills. In this study, we fit Deep Knowledge Tracing with Transformers (DKTT), Dynamic Key-Value Memory Networks (DKVMN), and Knowledge Tracing Machines (KTM) to a large dataset from a cognitive training system. DKVMN achieved the highest AUC (0.739) of the algorithms. To explore connections between math skills and cognitive skills, the data was split into cognitive and math items. DKVMN’s AUC on the math items was higher (0.745) than on the cognitive (0.706). Notably, the split model AUCs did not differ from skill-level AUCs produced by a model trained on the entire dataset, suggesting that math performance did not improve DKVMN’s cognitive predictions and vice versa.}, keywords = {}, pubstate = {published}, tppubtype = {proceedings} } Close Cognitive training aims to improve skills such as working memory capacity and spatial ability, which have been linked to math skills. In this study, we fit Deep Knowledge Tracing with Transformers (DKTT), Dynamic Key-Value Memory Networks (DKVMN), and Knowledge Tracing Machines (KTM) to a large dataset from a cognitive training system. DKVMN achieved the highest AUC (0.739) of the algorithms. To explore connections between math skills and cognitive skills, the data was split into cognitive and math items. DKVMN’s AUC on the math items was higher (0.745) than on the cognitive (0.706). Notably, the split model AUCs did not differ from skill-level AUCs produced by a model trained on the entire dataset, suggesting that math performance did not improve DKVMN’s cognitive predictions and vice versa. Close https://link.springer.com/chapter/10.1007/978-3-031-11647-6_81 doi:https://doi.org/10.1007/978-3-031-11647-6_81 Close
	Samson Nivins, Bruno Sauce, Magnus Liebherr, Nicholas Judd, Torkel Klingberg The Long-Term Impact of Digital Media on Brain Development in Children Journal Article medRxiv, 2022. Links @article{Nivins2022b, title = {The Long-Term Impact of Digital Media on Brain Development in Children}, author = {Samson Nivins, Bruno Sauce, Magnus Liebherr, Nicholas Judd, Torkel Klingberg}, url = {https://www.medrxiv.org/content/10.1101/2022.07.01.22277142v2}, doi = {https://doi.org/10.1101/2022.07.01.22277142}, year = {2022}, date = {2022-07-05}, journal = {medRxiv}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close https://www.medrxiv.org/content/10.1101/2022.07.01.22277142v2 doi:https://doi.org/10.1101/2022.07.01.22277142 Close
	Bruno Sauce, Magnus Liebherr, Nicholas Judd, Torkel Klingberg The impact of digital media on children’s intelligence while controlling for genetic differences in cognition and socioeconomic background Journal Article Scientific reports, 12 (1), pp. 7720, 2022. Abstract \| Links @article{Sauce2022, title = {The impact of digital media on children’s intelligence while controlling for genetic differences in cognition and socioeconomic background}, author = {Bruno Sauce, Magnus Liebherr, Nicholas Judd, Torkel Klingberg}, url = {https://www.nature.com/articles/s41598-022-11341-2}, doi = {https://doi.org/10.1038/s41598-022-11341-2}, year = {2022}, date = {2022-05-11}, journal = {Scientific reports}, volume = {12}, number = {1}, pages = {7720}, abstract = {Digital media defines modern childhood, but its cognitive effects are unclear and hotly debated. We believe that studies with genetic data could clarify causal claims and correct for the typically unaccounted role of genetic predispositions. Here, we estimated the impact of different types of screen time (watching, socializing, or gaming) on children’s intelligence while controlling for the confounding effects of genetic differences in cognition and socioeconomic status. We analyzed 9855 children from the USA who were part of the ABCD dataset with measures of intelligence at baseline (ages 9–10) and after two years. At baseline, time watching (r = − 0.12) and socializing (r = − 0.10) were negatively correlated with intelligence, while gaming did not correlate. After two years, gaming positively impacted intelligence (standardized β = + 0.17), but socializing had no effect. This is consistent with cognitive benefits documented in experimental studies on video gaming. Unexpectedly, watching videos also benefited intelligence (standardized β = + 0.12), contrary to prior research on the effect of watching TV. Although, in a posthoc analysis, this was not significant if parental education (instead of SES) was controlled for. Broadly, our results are in line with research on the malleability of cognitive abilities from environmental factors, such as cognitive training and the Flynn effect.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Digital media defines modern childhood, but its cognitive effects are unclear and hotly debated. We believe that studies with genetic data could clarify causal claims and correct for the typically unaccounted role of genetic predispositions. Here, we estimated the impact of different types of screen time (watching, socializing, or gaming) on children’s intelligence while controlling for the confounding effects of genetic differences in cognition and socioeconomic status. We analyzed 9855 children from the USA who were part of the ABCD dataset with measures of intelligence at baseline (ages 9–10) and after two years. At baseline, time watching (r = − 0.12) and socializing (r = − 0.10) were negatively correlated with intelligence, while gaming did not correlate. After two years, gaming positively impacted intelligence (standardized β = + 0.17), but socializing had no effect. This is consistent with cognitive benefits documented in experimental studies on video gaming. Unexpectedly, watching videos also benefited intelligence (standardized β = + 0.12), contrary to prior research on the effect of watching TV. Although, in a posthoc analysis, this was not significant if parental education (instead of SES) was controlled for. Broadly, our results are in line with research on the malleability of cognitive abilities from environmental factors, such as cognitive training and the Flynn effect. Close https://www.nature.com/articles/s41598-022-11341-2 doi:https://doi.org/10.1038/s41598-022-11341-2 Close
	Torkel Klingberg, Nicholas Judd, Bruno Sauce Assessing the impact of environmental factors on the adolescent brain: the importance of regional analyses and genetic controls Journal Article World Psychiatry, 21 (1), pp. 146, 2022. Links @article{Klingberg2022, title = {Assessing the impact of environmental factors on the adolescent brain: the importance of regional analyses and genetic controls}, author = {Torkel Klingberg, Nicholas Judd, Bruno Sauce}, url = {https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8751551/}, doi = {10.1002/wps.20934}, year = {2022}, date = {2022-01-11}, journal = {World Psychiatry}, volume = {21}, number = {1}, pages = {146}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8751551/ doi:10.1002/wps.20934 Close
	Samson Nivins, Bruno Sauce, Magnus Liebherr, Nicholas Judd, Torkel Klingberg Digital media does not harm (nor benefit) brain development in children Journal Article medRxiv, 2022. Abstract \| Links @article{Nivins2022, title = {Digital media does not harm (nor benefit) brain development in children}, author = {Samson Nivins, Bruno Sauce, Magnus Liebherr, Nicholas Judd, Torkel Klingberg}, url = {https://www.medrxiv.org/content/10.1101/2022.07.01.22277142v1?%253fcollection=}, doi = {https://doi.org/10.1101/2022.07.01.22277142}, year = {2022}, date = {2022-01-01}, journal = {medRxiv}, abstract = {Importance: Digital media takes an increasingly large part of children’s time, but the effect on brain development is unclear. Objective: To investigate the effects of digital media (watching television and videos, using social media, or playing video games respectively) on the development of the cortex, striatum, and cerebellum over two years. Design, setting, and participants: A prospective, multicenter, longitudinal study of children from the Adolescent Brain and Cognitive Development Study, recruited between 2016-2018. Children underwent magnetic resonance imaging scan at two different time points and completed the Youth Screen Time Survey at first timepoint, answering questions about digital media use. The analysis controlled for differences in socioeconomic status (SES) and polygenic scores for educational attainment. Exposure: Digital media use. Main outcome measures: The primary outcome measure was the changes in the global cortical surface area. Results: 6492 children (age in months, mean [SD] = 118.6 [7.2], i.e., 9.9 years were included at the baseline. Of these, 4502 children (age in months = 142.6 [7.6], i.e., 11.9 years were included at the two years follow-up. The average time spent by children on screen time was 2.2h/day for watching television and videos, 0.4h/day for using social media, and 0.9h/day for playing video games. Over the two-year observation period, the average cortical surface area increased by approximately 2%, reflecting normal cortical development. The amount of time spent playing video games was weakly but positively correlated to change in global cortical surface area (standardised beta, β = 0.03; 95% CI [0.001 – 0.06]; P=.06). No global or regional effect on brain development was observed for a time watching television and videos or using social media. However, the regional analysis showed that playing video games was associated with a larger increase in the volume of the cerebellum (β = 0.01 [0.001 – 0.02]; P=.02). Conclusions and Relevance: This study does not suggest that digital media use in children harms brain development in mid-childhood and within a window of two years, but a longer follow-up is necessary. Question: Does the use of digital media affect brain development in children aged 9-10 years of age? Findings: In this two-year longitudinal study of 4502 children, we found no effect of playing video games, watching television, or using social media on the development of cortical surface area. playing video games was associated with a larger increase in the volume of cerebellum. Meaning: This study does not indicate that the use of digital media harms brain development.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Importance: Digital media takes an increasingly large part of children’s time, but the effect on brain development is unclear. Objective: To investigate the effects of digital media (watching television and videos, using social media, or playing video games respectively) on the development of the cortex, striatum, and cerebellum over two years. Design, setting, and participants: A prospective, multicenter, longitudinal study of children from the Adolescent Brain and Cognitive Development Study, recruited between 2016-2018. Children underwent magnetic resonance imaging scan at two different time points and completed the Youth Screen Time Survey at first timepoint, answering questions about digital media use. The analysis controlled for differences in socioeconomic status (SES) and polygenic scores for educational attainment. Exposure: Digital media use. Main outcome measures: The primary outcome measure was the changes in the global cortical surface area. Results: 6492 children (age in months, mean [SD] = 118.6 [7.2], i.e., 9.9 years were included at the baseline. Of these, 4502 children (age in months = 142.6 [7.6], i.e., 11.9 years were included at the two years follow-up. The average time spent by children on screen time was 2.2h/day for watching television and videos, 0.4h/day for using social media, and 0.9h/day for playing video games. Over the two-year observation period, the average cortical surface area increased by approximately 2%, reflecting normal cortical development. The amount of time spent playing video games was weakly but positively correlated to change in global cortical surface area (standardised beta, β = 0.03; 95% CI [0.001 – 0.06]; P=.06). No global or regional effect on brain development was observed for a time watching television and videos or using social media. However, the regional analysis showed that playing video games was associated with a larger increase in the volume of the cerebellum (β = 0.01 [0.001 – 0.02]; P=.02). Conclusions and Relevance: This study does not suggest that digital media use in children harms brain development in mid-childhood and within a window of two years, but a longer follow-up is necessary. Question: Does the use of digital media affect brain development in children aged 9-10 years of age? Findings: In this two-year longitudinal study of 4502 children, we found no effect of playing video games, watching television, or using social media on the development of cortical surface area. playing video games was associated with a larger increase in the volume of cerebellum. Meaning: This study does not indicate that the use of digital media harms brain development. Close https://www.medrxiv.org/content/10.1101/2022.07.01.22277142v1?%253fcollection= doi:https://doi.org/10.1101/2022.07.01.22277142 Close
2021
	Nicholas Judd, Bruno Sauce, Torkel Klingberg The malleability of intelligence: the effects of schooling, genetic factors, socioeconomic status, and their interplay in children. Journal Article PsyArXiv, 2021. Links @article{judd2021malleabilityb, title = {The malleability of intelligence: the effects of schooling, genetic factors, socioeconomic status, and their interplay in children.}, author = {Nicholas Judd and Bruno Sauce and Torkel Klingberg}, url = {https://psyarxiv.com/96pj4/}, year = {2021}, date = {2021-09-23}, journal = {PsyArXiv}, publisher = {PsyArXiv}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close https://psyarxiv.com/96pj4/ Close
	Da-Wei Zhang, Anna Zaphf, Torkel Klingberg Resting State EEG Related to Mathematical Improvement After Spatial Training in Children Journal Article Frontiers in Human Neuroscience, 15 , pp. 379, 2021. Abstract \| Links @article{zhang2021resting, title = {Resting State EEG Related to Mathematical Improvement After Spatial Training in Children}, author = {Da-Wei Zhang and Anna Zaphf and Torkel Klingberg}, url = {https://www.frontiersin.org/articles/10.3389/fnhum.2021.698367/full}, year = {2021}, date = {2021-09-08}, journal = {Frontiers in Human Neuroscience}, volume = {15}, pages = {379}, publisher = {Frontiers}, abstract = {Spatial cognitive abilities, including mental rotation (MR) and visuo-spatial working memory (vsWM) are correlated with mathematical performance, and several studies have shown that training of these abilities can enhance mathematical performance. Here, we investigated the behavioral and neural correlates of MR and vsWM training combined with number line (NL) training. Fifty-seven children, aged 6–7, performed 25 days of NL training combined with either vsWM or MR and participated in an Electroencephalography (EEG)-session in school to measure resting state activity and steady-state visual evoked potentials during a vsWM task before and after training. Fifty children, aged 6–7, received usual teaching and acted as a control group. Compared to the control group, both training groups improved on a combined measure of mathematics. Cognitive improvement was specific to the training. Significant pre-post changes in resting state-EEG (rs-EEG), common to both training groups, were found for power as well as for coherence, with no significant differences in rs-EEG-changes between the vsWM and MR groups. Two of the common rs-EEG changes were correlated with mathematical improvement: (1) an increase in coherence between the central frontal lobe and the right parietal lobe in frequencies ranging from 16 to 25 Hz, and (2) an increase in coherence between the left frontal lobe and the right parietal lobe ranging from 23 to 25 Hz. These results indicate that changes in fronto-parietal coherence are related to an increase in mathematical performance, which thus might be a useful measure in further investigations of mathematical interventions in children.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Spatial cognitive abilities, including mental rotation (MR) and visuo-spatial working memory (vsWM) are correlated with mathematical performance, and several studies have shown that training of these abilities can enhance mathematical performance. Here, we investigated the behavioral and neural correlates of MR and vsWM training combined with number line (NL) training. Fifty-seven children, aged 6–7, performed 25 days of NL training combined with either vsWM or MR and participated in an Electroencephalography (EEG)-session in school to measure resting state activity and steady-state visual evoked potentials during a vsWM task before and after training. Fifty children, aged 6–7, received usual teaching and acted as a control group. Compared to the control group, both training groups improved on a combined measure of mathematics. Cognitive improvement was specific to the training. Significant pre-post changes in resting state-EEG (rs-EEG), common to both training groups, were found for power as well as for coherence, with no significant differences in rs-EEG-changes between the vsWM and MR groups. Two of the common rs-EEG changes were correlated with mathematical improvement: (1) an increase in coherence between the central frontal lobe and the right parietal lobe in frequencies ranging from 16 to 25 Hz, and (2) an increase in coherence between the left frontal lobe and the right parietal lobe ranging from 23 to 25 Hz. These results indicate that changes in fronto-parietal coherence are related to an increase in mathematical performance, which thus might be a useful measure in further investigations of mathematical interventions in children. Close https://www.frontiersin.org/articles/10.3389/fnhum.2021.698367/full Close
	Bruno Sauce, John Wiedenhoeft, Nicholas Judd, Torkel Klingberg Change by challenge: A common genetic basis behind childhood cognitive development and cognitive training Journal Article Nature Science of Learning, 2021. Abstract \| Links @article{Sauce2021, title = {Change by challenge: A common genetic basis behind childhood cognitive development and cognitive training}, author = {Bruno Sauce, John Wiedenhoeft, Nicholas Judd, Torkel Klingberg}, doi = {10.1038/s41539-021-00096-6}, year = {2021}, date = {2021-06-02}, journal = {Nature Science of Learning}, abstract = {The interplay of genetic and environmental factors behind cognitive development has preoccupied multiple fields of science and sparked heated debates over the decades. Here we tested the hypothesis that developmental genes rely heavily on cognitive challenges—as opposed to natural maturation. Starting with a polygenic score (cogPGS) that previously explained variation in cognitive performance in adults, we estimated its effect in 344 children and adolescents (mean age of 12 years old, ranging from 6 to 25) who showed changes in working memory (WM) in two distinct samples: (1) a developmental sample showing significant WM gains after 2 years of typical, age-related development, and (2) a training sample showing significant, experimentally-induced WM gains after 25 days of an intense WM training. We found that the same genetic factor, cogPGS, significantly explained the amount of WM gain in both samples. And there was no interaction of cogPGS with sample, suggesting that those genetic factors are neutral to whether the WM gains came from development or training. These results represent evidence that cognitive challenges are a central piece in the gene-environment interplay during cognitive development. We believe our study sheds new light on previous findings of interindividual differences in education (rich-get-richer and compensation effects), brain plasticity in children, and the heritability increase of intelligence across the lifespan.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The interplay of genetic and environmental factors behind cognitive development has preoccupied multiple fields of science and sparked heated debates over the decades. Here we tested the hypothesis that developmental genes rely heavily on cognitive challenges—as opposed to natural maturation. Starting with a polygenic score (cogPGS) that previously explained variation in cognitive performance in adults, we estimated its effect in 344 children and adolescents (mean age of 12 years old, ranging from 6 to 25) who showed changes in working memory (WM) in two distinct samples: (1) a developmental sample showing significant WM gains after 2 years of typical, age-related development, and (2) a training sample showing significant, experimentally-induced WM gains after 25 days of an intense WM training. We found that the same genetic factor, cogPGS, significantly explained the amount of WM gain in both samples. And there was no interaction of cogPGS with sample, suggesting that those genetic factors are neutral to whether the WM gains came from development or training. These results represent evidence that cognitive challenges are a central piece in the gene-environment interplay during cognitive development. We believe our study sheds new light on previous findings of interindividual differences in education (rich-get-richer and compensation effects), brain plasticity in children, and the heritability increase of intelligence across the lifespan. Close doi:10.1038/s41539-021-00096-6 Close
	Torkel Klingberg, Nicholas Judd, Bruno Sauce Assessing the impact of environmental factors on the adolescent brain: the importance of regional analyses and genetic controls Journal Article World Psychiatry, 2021. @article{Klingberg2021, title = {Assessing the impact of environmental factors on the adolescent brain: the importance of regional analyses and genetic controls}, author = {Torkel Klingberg, Nicholas Judd, Bruno Sauce}, year = {2021}, date = {2021-05-10}, journal = {World Psychiatry}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close
	Torkel Klingberg, Bruno Sauce Working memory training: From the laboratory to schools Book Chapter Borst, Gregoire (Ed.): Cambridge Handbook of Cognitive Development, 2021. @inbook{KlingbergBookC2020, title = {Working memory training: From the laboratory to schools}, author = {Torkel Klingberg, Bruno Sauce}, editor = {Gregoire Borst}, year = {2021}, date = {2021-05-04}, booktitle = {Cambridge Handbook of Cognitive Development}, keywords = {}, pubstate = {published}, tppubtype = {inbook} } Close
	Nicholas Judd, Torkel Klingberg Training spatial cognition enhances mathematical learning in a randomized study of 17,000 children Journal Article Nature Human Behaviour, 2021. Abstract \| Links @article{Judd2020b, title = {Training spatial cognition enhances mathematical learning in a randomized study of 17,000 children}, author = {Nicholas Judd, Torkel Klingberg}, doi = {10.1038/s41562-021-01118-4}, year = {2021}, date = {2021-05-01}, journal = {Nature Human Behaviour}, abstract = {Spatial and mathematical abilities are strongly associated. Here, we analysed data from 17,648 children, aged 6–8 years, who performed 7 weeks of mathematical training together with randomly assigned spatial cognitive training with tasks demanding more spatial manipulation (mental rotation or tangram), maintenance of spatial information (a visuospatial working memory task) or spatial, non-verbal reasoning. We found that the type of cognitive training children performed had a significant impact on mathematical learning, with training of visuospatial working memory and reasoning being the most effective. This large, community-based study shows that spatial cognitive training can result in transfer to academic abilities, and that reasoning ability and maintenance of spatial information is relevant for mathematics learning in young children.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Spatial and mathematical abilities are strongly associated. Here, we analysed data from 17,648 children, aged 6–8 years, who performed 7 weeks of mathematical training together with randomly assigned spatial cognitive training with tasks demanding more spatial manipulation (mental rotation or tangram), maintenance of spatial information (a visuospatial working memory task) or spatial, non-verbal reasoning. We found that the type of cognitive training children performed had a significant impact on mathematical learning, with training of visuospatial working memory and reasoning being the most effective. This large, community-based study shows that spatial cognitive training can result in transfer to academic abilities, and that reasoning ability and maintenance of spatial information is relevant for mathematics learning in young children. Close doi:10.1038/s41562-021-01118-4 Close
	Nicholas Judd, Torkel Klingberg, Douglas Sjöwall Working memory capacity, variability, and response to intervention at age 6 and its association to inattention and mathematics age 9 Journal Article Cognitive Development, 58 (12), pp. 101013, 2021. Abstract \| Links @article{Judd2021, title = {Working memory capacity, variability, and response to intervention at age 6 and its association to inattention and mathematics age 9}, author = {Nicholas Judd, Torkel Klingberg, Douglas Sjöwall}, url = {https://www.sciencedirect.com/science/article/pii/S0885201421000083}, doi = {https://doi.org/10.1016/j.cogdev.2021.101013}, year = {2021}, date = {2021-04-01}, journal = {Cognitive Development}, volume = {58}, number = {12}, pages = {101013}, abstract = {Classically, neuropsychological evaluation only estimates an individual’s performance at one time point. For example, working memory (WM) capacity is commonly determined in a single test session. However, recent research in WM plasticity and variability has suggested performance over several sessions/days might aid in evaluating children. Here, we explored four temporal properties of WM: WM measured once, as a mean over three days (multiple-session-baseline performance), variability over 8 weeks, and performance improvement over an 8-week WM training program. To examine independence we controlled for a single-session, multiple task WM assessment while predicting inattention and mathematics three years later (n = 178, mean age 80 months at training, 49 % boys). Our results showed improved prediction for mathematics from WM training improvement and variability, yet this was not the case for inattention. While the additional variance added was not substantial, our results indicate clinically relevant information present in these alternative WM measures.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Classically, neuropsychological evaluation only estimates an individual’s performance at one time point. For example, working memory (WM) capacity is commonly determined in a single test session. However, recent research in WM plasticity and variability has suggested performance over several sessions/days might aid in evaluating children. Here, we explored four temporal properties of WM: WM measured once, as a mean over three days (multiple-session-baseline performance), variability over 8 weeks, and performance improvement over an 8-week WM training program. To examine independence we controlled for a single-session, multiple task WM assessment while predicting inattention and mathematics three years later (n = 178, mean age 80 months at training, 49 % boys). Our results showed improved prediction for mathematics from WM training improvement and variability, yet this was not the case for inattention. While the additional variance added was not substantial, our results indicate clinically relevant information present in these alternative WM measures. Close https://www.sciencedirect.com/science/article/pii/S0885201421000083 doi:https://doi.org/10.1016/j.cogdev.2021.101013 Close
2020
	Carlos Guillermo Bozzoli, Maria Luz Gonzalez-Gadea, Maria Julia Hermida, Lucía Navarro, Tomás Olego, Torkel Klingberg Digital, mathematical and cognitive training: Evidence from a randomized trial Journal Article PsyArXiv, 2020. Abstract \| Links @article{Bozzoli2020b, title = {Digital, mathematical and cognitive training: Evidence from a randomized trial}, author = {Carlos Guillermo Bozzoli, Maria Luz Gonzalez-Gadea, Maria Julia Hermida, Lucía Navarro, Tomás Olego, Torkel Klingberg}, url = {https://psyarxiv.com/24ej7/}, doi = {10.31234/osf.io/24ej7}, year = {2020}, date = {2020-11-02}, journal = {PsyArXiv}, abstract = {In this paper, we experimentally evaluate a cognitive training tool that aims to improve children’s mathematical ability through technology in rural primary schools in Argentina. We conducted a large cluster-randomized trial: schools in the treatment group used an app to train mathematical skills, while schools in the control group received a literacy book. We tested the math skills of 1,304 children in the 2nd through 6th grades from 80 rural schools and applied three cognitive tests: digit-span (working memory), face-perception (attention to objects), and block design (visuospatial reasoning), directly before and after the 10-week intervention period. In schools that received the treatment, we found no improvement in the digit-span or face-perception tests, but significant and positive effects in visuospatial reasoning and mathematical abilities. The improvement among students from treatment schools was 54 percentage points higher in math skills and 42 percentage points higher in visuospatial abilities than the gains by students in control schools. This study suggests this intervention is a feasible and effective way of enhancing the mathematical and cognitive abilities of children in rural areas.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close In this paper, we experimentally evaluate a cognitive training tool that aims to improve children’s mathematical ability through technology in rural primary schools in Argentina. We conducted a large cluster-randomized trial: schools in the treatment group used an app to train mathematical skills, while schools in the control group received a literacy book. We tested the math skills of 1,304 children in the 2nd through 6th grades from 80 rural schools and applied three cognitive tests: digit-span (working memory), face-perception (attention to objects), and block design (visuospatial reasoning), directly before and after the 10-week intervention period. In schools that received the treatment, we found no improvement in the digit-span or face-perception tests, but significant and positive effects in visuospatial reasoning and mathematical abilities. The improvement among students from treatment schools was 54 percentage points higher in math skills and 42 percentage points higher in visuospatial abilities than the gains by students in control schools. This study suggests this intervention is a feasible and effective way of enhancing the mathematical and cognitive abilities of children in rural areas. Close https://psyarxiv.com/24ej7/ doi:10.31234/osf.io/24ej7 Close
	Carlos Bozzoli, Maria Gonzalez-Gadea, Maria Hermida, Lucía Navarro, Tomás Olego, Torkel Klingberg Digital, mathematical and cognitive training: Evidence from a randomized trial Journal Article PsyArXiv, 2020. Abstract \| Links @article{Bozzoli2020, title = {Digital, mathematical and cognitive training: Evidence from a randomized trial}, author = {Carlos Bozzoli, Maria Gonzalez-Gadea, Maria Hermida, Lucía Navarro, Tomás Olego, Torkel Klingberg}, url = {https://psyarxiv.com/24ej7/}, doi = {https://doi.org/10.31234/osf.io/24ej7}, year = {2020}, date = {2020-11-01}, journal = {PsyArXiv}, abstract = {In this paper, we experimentally evaluate a cognitive training tool that aims to improve children’s mathematical ability through technology in rural primary schools in Argentina. We conducted a large cluster-randomized trial: schools in the treatment group used an app to train mathematical skills, while schools in the control group received a literacy book. We tested the math skills of 1,304 children in the 2nd through 6th grades from 80 rural schools and applied three cognitive tests: digit-span (working memory), face-perception (attention to objects), and block design (visuospatial reasoning), directly before and after the 10-week intervention period. In schools that received the treatment, we found no improvement in the digit-span or face-perception tests, but significant and positive effects in visuospatial reasoning and mathematical abilities. The improvement among students from treatment schools was 54 percentage points higher in math skills and 42 percentage points higher in visuospatial abilities than the gains by students in control schools. This study suggests this intervention is a feasible and effective way of enhancing the mathematical and cognitive abilities of children in rural areas.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close In this paper, we experimentally evaluate a cognitive training tool that aims to improve children’s mathematical ability through technology in rural primary schools in Argentina. We conducted a large cluster-randomized trial: schools in the treatment group used an app to train mathematical skills, while schools in the control group received a literacy book. We tested the math skills of 1,304 children in the 2nd through 6th grades from 80 rural schools and applied three cognitive tests: digit-span (working memory), face-perception (attention to objects), and block design (visuospatial reasoning), directly before and after the 10-week intervention period. In schools that received the treatment, we found no improvement in the digit-span or face-perception tests, but significant and positive effects in visuospatial reasoning and mathematical abilities. The improvement among students from treatment schools was 54 percentage points higher in math skills and 42 percentage points higher in visuospatial abilities than the gains by students in control schools. This study suggests this intervention is a feasible and effective way of enhancing the mathematical and cognitive abilities of children in rural areas. Close https://psyarxiv.com/24ej7/ doi:https://doi.org/10.31234/osf.io/24ej7 Close
	George Zacharopoulos, Torkel Klingberg, Roi Cohen Kadosh Structural variation within the left globus pallidus is associated with task-switching, not stimulus updating or distractor filtering Journal Article Cognitive Neuroscience, 11 (4), pp. 229-238, 2020. Abstract \| Links @article{Zacharopoulos2020b, title = {Structural variation within the left globus pallidus is associated with task-switching, not stimulus updating or distractor filtering}, author = {George Zacharopoulos, Torkel Klingberg, Roi Cohen Kadosh}, url = {https://www.tandfonline.com/doi/full/10.1080/17588928.2020.1813699}, doi = {https://doi.org/10.1080/17588928.2020.1813699}, year = {2020}, date = {2020-10-01}, journal = {Cognitive Neuroscience}, volume = {11}, number = {4}, pages = {229-238}, abstract = {Cognitive control is a pivotal aspect of cognition and it is impaired in many clinical populations. To date, several distinct types of cognitive control have been proposed, and prior work demonstrated the instrumental role of basal ganglia, frontal and parietal regions. However, the role of the structural variation of these regions in cognitive control functions is poorly understood. Here, we examined in 39 adults the association between regional brain volume and three major types of cognitive control: (i) stimulus updating, (ii) task-switching, and (iii) distractor filtering. The volume of the globus pallidus was positively correlated with individual variation in task-switching , and was anatomically specific to the left hemisphere. Importantly, this region did not track performance in distractor filtering or stimulus updating. We then aimed to use transcranial direct current stimulation to target the left midline subcortical structures. However, we did not find an effect on task-switching. While the null effect in the brain stimulation prevents us from drawing causal inference from the role of globus pallidus on task-switching, our structural results reveal a novel and highly specific neurostructural mechanism for task-switching and provide a further understanding of the link between cognitive control functions and the human brain.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Cognitive control is a pivotal aspect of cognition and it is impaired in many clinical populations. To date, several distinct types of cognitive control have been proposed, and prior work demonstrated the instrumental role of basal ganglia, frontal and parietal regions. However, the role of the structural variation of these regions in cognitive control functions is poorly understood. Here, we examined in 39 adults the association between regional brain volume and three major types of cognitive control: (i) stimulus updating, (ii) task-switching, and (iii) distractor filtering. The volume of the globus pallidus was positively correlated with individual variation in task-switching , and was anatomically specific to the left hemisphere. Importantly, this region did not track performance in distractor filtering or stimulus updating. We then aimed to use transcranial direct current stimulation to target the left midline subcortical structures. However, we did not find an effect on task-switching. While the null effect in the brain stimulation prevents us from drawing causal inference from the role of globus pallidus on task-switching, our structural results reveal a novel and highly specific neurostructural mechanism for task-switching and provide a further understanding of the link between cognitive control functions and the human brain. Close https://www.tandfonline.com/doi/full/10.1080/17588928.2020.1813699 doi:https://doi.org/10.1080/17588928.2020.1813699 Close
	Nicholas Judd, Bruno Sauce, John Wiedenhoeft, Jeshua Tromp, Bader Chaarani, Alexander Schliep, Betteke van Noort, Jani Penttilä, Yvonne Grimmer, Corinna Insensee, Andreas Becker, Tobias Banaschewski, Arun L W Bokde, Erin Burke Quinlan, Sylvane Desrivières, Herta Flor, Antoine Grigis, Penny Gowland, Andreas Heinz, Bernd Ittermann, Jean-Luc Martinot, Marie-Laure Paillère Martinot, Eric Artiges, Frauke Nees, Dimitri Papadopoulos Orfanos, Tomáš Paus, Luise Poustka, Sarah Hohmann, Sabina Millenet, Juliane H Fröhner, Michael N Smolka, Henrik Walter, Robert Whelan, Gunter Schumann, Hugh Garavan, Torkel Klingberg Cognitive and brain development is independently influenced by socioeconomic status and polygenic scores for educational attainment Journal Article Proceedings of the National Academy of Sciences, 117 (22), pp. 12411–12418, 2020, ISSN: 0027-8424. Abstract \| Links @article{Judd2020, title = {Cognitive and brain development is independently influenced by socioeconomic status and polygenic scores for educational attainment}, author = {Nicholas Judd and Bruno Sauce and John Wiedenhoeft and Jeshua Tromp and Bader Chaarani and Alexander Schliep and Betteke van Noort and Jani Penttilä and Yvonne Grimmer and Corinna Insensee and Andreas Becker and Tobias Banaschewski and Arun L W Bokde and Erin Burke Quinlan and Sylvane Desrivi{è}res and Herta Flor and Antoine Grigis and Penny Gowland and Andreas Heinz and Bernd Ittermann and Jean-Luc Martinot and Marie-Laure {Paill{è}re Martinot} and Eric Artiges and Frauke Nees and Dimitri {Papadopoulos Orfanos} and Tomáš Paus and Luise Poustka and Sarah Hohmann and Sabina Millenet and Juliane H Fröhner and Michael N Smolka and Henrik Walter and Robert Whelan and Gunter Schumann and Hugh Garavan and Torkel Klingberg}, url = {http://www.pnas.org/lookup/doi/10.1073/pnas.2001228117}, doi = {10.1073/pnas.2001228117}, issn = {0027-8424}, year = {2020}, date = {2020-06-01}, journal = {Proceedings of the National Academy of Sciences}, volume = {117}, number = {22}, pages = {12411--12418}, abstract = {Genetic factors and socioeconomic status (SES) inequalities play a large role in educational attainment, and both have been associated with variations in brain structure and cognition. However, genetics and SES are correlated, and no prior study has assessed their neural associations independently. Here we used a polygenic score for educational attainment (EduYears-PGS), as well as SES, in a longitudinal study of 551 adolescents to tease apart genetic and environmental associations with brain development and cognition. Subjects received a structural MRI scan at ages 14 and 19. At both time points, they performed three working memory (WM) tasks. SES and EduYears-PGS were correlated ( r = 0.27) and had both common and independent associations with brain structure and cognition. Specifically, lower SES was related to less total cortical surface area and lower WM. EduYears-PGS was also related to total cortical surface area, but in addition had a regional association with surface area in the right parietal lobe, a region related to nonverbal cognitive functions, including mathematics, spatial cognition, and WM. SES, but not EduYears-PGS, was related to a change in total cortical surface area from age 14 to 19. This study demonstrates a regional association of EduYears-PGS and the independent prediction of SES with cognitive function and brain development. It suggests that the SES inequalities, in particular parental education, are related to global aspects of cortical development, and exert a persistent influence on brain development during adolescence.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Genetic factors and socioeconomic status (SES) inequalities play a large role in educational attainment, and both have been associated with variations in brain structure and cognition. However, genetics and SES are correlated, and no prior study has assessed their neural associations independently. Here we used a polygenic score for educational attainment (EduYears-PGS), as well as SES, in a longitudinal study of 551 adolescents to tease apart genetic and environmental associations with brain development and cognition. Subjects received a structural MRI scan at ages 14 and 19. At both time points, they performed three working memory (WM) tasks. SES and EduYears-PGS were correlated ( r = 0.27) and had both common and independent associations with brain structure and cognition. Specifically, lower SES was related to less total cortical surface area and lower WM. EduYears-PGS was also related to total cortical surface area, but in addition had a regional association with surface area in the right parietal lobe, a region related to nonverbal cognitive functions, including mathematics, spatial cognition, and WM. SES, but not EduYears-PGS, was related to a change in total cortical surface area from age 14 to 19. This study demonstrates a regional association of EduYears-PGS and the independent prediction of SES with cognitive function and brain development. It suggests that the SES inequalities, in particular parental education, are related to global aspects of cortical development, and exert a persistent influence on brain development during adolescence. Close http://www.pnas.org/lookup/doi/10.1073/pnas.2001228117 doi:10.1073/pnas.2001228117 Close
	George Zacharopoulos, Torkel Klingberg, Roi Cohen Kadosh Cortical surface area of the left frontal pole is associated with visuospatial working memory capacity Journal Article Neuropsychologia, 143 , 2020. Abstract \| Links @article{Zacharopoulos2020, title = {Cortical surface area of the left frontal pole is associated with visuospatial working memory capacity}, author = {George Zacharopoulos, Torkel Klingberg, Roi Cohen Kadosh}, url = {https://www.sciencedirect.com/science/article/pii/S0028393220301573}, doi = {https://doi.org/10.1016/j.neuropsychologia.2020.107486}, year = {2020}, date = {2020-06-01}, journal = {Neuropsychologia}, volume = {143}, abstract = {Working memory, the ability to maintain and manipulate information over seconds, is central to cognition and it is impaired in many clinical populations. However, our knowledge of the structural properties associated with individual variation in visuospatial working memory capacity is currently poor. Across two locations (Stockholm and Oxford), we examined how regional surface area and cortical thickness in frontal and parietal regions were related to visuospatial working memory capacity. We found a negative association between visuospatial working memory capacity and the surface area of the left frontal pole across both locations, and this finding was consistently present in each of the two locations separately. Importantly, this association was specific to (i) the surface area (not cortical thickness), (ii) the left side of the brain, (iii) and the visuospatial rather than the verbal modality. This result reveals a novel and highly specific neurobiological association with visuospatial working memory which could be further explored in studies with a wider range of psychological tests and in clinical populations.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Working memory, the ability to maintain and manipulate information over seconds, is central to cognition and it is impaired in many clinical populations. However, our knowledge of the structural properties associated with individual variation in visuospatial working memory capacity is currently poor. Across two locations (Stockholm and Oxford), we examined how regional surface area and cortical thickness in frontal and parietal regions were related to visuospatial working memory capacity. We found a negative association between visuospatial working memory capacity and the surface area of the left frontal pole across both locations, and this finding was consistently present in each of the two locations separately. Importantly, this association was specific to (i) the surface area (not cortical thickness), (ii) the left side of the brain, (iii) and the visuospatial rather than the verbal modality. This result reveals a novel and highly specific neurobiological association with visuospatial working memory which could be further explored in studies with a wider range of psychological tests and in clinical populations. Close https://www.sciencedirect.com/science/article/pii/S0028393220301573 doi:https://doi.org/10.1016/j.neuropsychologia.2020.107486 Close
2019
	Nicholas Judd, Bruno Sauce, John Wiedenhoeft, Jeshua Tromp, Bader Chaarani, Alexander Schliep, Argyris Stringaris, Betteke van Noort, Jani Penttilä, Yvonne Grimmer, Corinna Insensee, Andreas Becker, Tobias Banaschewski, Arun L W Bokde, Erin Burke Quinlan, Sylvane Desrivières, Herta Flor, Antoine Grigis, Penny Gowland, Bernd Ittermann, Jean-Luc Martinot, Marie-Laure Paillère Martinot, Eric Artiges, Frauke Nees, Dimitri Papadopoulos Orfanos, Tomáš Paus, Luise Poustka, Sarah Hohmann, Sabina Millenet, Juliane H Fröhner, Michael N Smolka, Henrik Walter, Robert Whelan, Gunter Schumann, Hugh Garavan, Torkel Klingberg Independent effects of socioeconomic status and genetics on adolescent cognition and brain development Journal Article bioRxiv, 2019. Abstract \| Links @article{Judd2019, title = {Independent effects of socioeconomic status and genetics on adolescent cognition and brain development}, author = {Nicholas Judd and Bruno Sauce and John Wiedenhoeft and Jeshua Tromp and Bader Chaarani and Alexander Schliep and Argyris Stringaris and Betteke van Noort and Jani Penttilä and Yvonne Grimmer and Corinna Insensee and Andreas Becker and Tobias Banaschewski and Arun L W Bokde and Erin Burke Quinlan and Sylvane Desrivi{è}res and Herta Flor and Antoine Grigis and Penny Gowland and Bernd Ittermann and Jean-Luc Martinot and Marie-Laure Paill{è}re Martinot and Eric Artiges and Frauke Nees and Dimitri Papadopoulos Orfanos and Tomáš Paus and Luise Poustka and Sarah Hohmann and Sabina Millenet and Juliane H Fröhner and Michael N Smolka and Henrik Walter and Robert Whelan and Gunter Schumann and Hugh Garavan and Torkel Klingberg}, doi = {10.1101/866624}, year = {2019}, date = {2019-12-06}, journal = {bioRxiv}, abstract = {Genetic factors and socioeconomic (SES) inequalities play a large role in educational attainment, and both have been associated with variations in brain structure and cognition. However, genetics and SES are correlated, and no prior study has assessed their neural effects independently. Here we used polygenic score for educational attainment (EduYears-PGS) as well as SES, in a longitudinal study of 551 adolescents, to tease apart genetic and environmental effects on brain development and cognition. Subjects received a structural MRI scan at ages 14 and 19. At both time-points, they performed three working memory (WM) tasks. SES and EduYears-PGS were correlated (r = 0.27) and had both common and independent effects on brain structure and cognition. Specifically, lower SES was related to less total cortical surface area and lower WM. EduYears-PGS was also related to total cortical surface area, but in addition had a regional effect on surface area in the right parietal lobe, a region related to nonverbal cognitive functions, including mathematics, problem solving and WM. SES, but not EduYears-PGS, affected the change in total cortical surface area from age 14 to 19. This is the first study demonstrating the regional effects of EduYears-PGS and the independent role of SES on cognitive function and brain development. It suggests that the SES effects are substantial, affect global aspects of cortical development, and exert a persistent influence on brain development during adolescence.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Genetic factors and socioeconomic (SES) inequalities play a large role in educational attainment, and both have been associated with variations in brain structure and cognition. However, genetics and SES are correlated, and no prior study has assessed their neural effects independently. Here we used polygenic score for educational attainment (EduYears-PGS) as well as SES, in a longitudinal study of 551 adolescents, to tease apart genetic and environmental effects on brain development and cognition. Subjects received a structural MRI scan at ages 14 and 19. At both time-points, they performed three working memory (WM) tasks. SES and EduYears-PGS were correlated (r = 0.27) and had both common and independent effects on brain structure and cognition. Specifically, lower SES was related to less total cortical surface area and lower WM. EduYears-PGS was also related to total cortical surface area, but in addition had a regional effect on surface area in the right parietal lobe, a region related to nonverbal cognitive functions, including mathematics, problem solving and WM. SES, but not EduYears-PGS, affected the change in total cortical surface area from age 14 to 19. This is the first study demonstrating the regional effects of EduYears-PGS and the independent role of SES on cognitive function and brain development. It suggests that the SES effects are substantial, affect global aspects of cortical development, and exert a persistent influence on brain development during adolescence. Close doi:10.1101/866624 Close
	Fahimeh Darki, Bruno Sauce, Torkel Klingberg Inter-Individual Differences in Striatal Connectivity Is Related to Executive Function Through Fronto-Parietal Connectivity Journal Article Cerebral Cortex, pp. 1–10, 2019, ISSN: 1047-3211. Abstract \| Links @article{Darki2019, title = {Inter-Individual Differences in Striatal Connectivity Is Related to Executive Function Through Fronto-Parietal Connectivity}, author = {Fahimeh Darki and Bruno Sauce and Torkel Klingberg}, url = {https://academic.oup.com/cercor/advance-article/doi/10.1093/cercor/bhz117/5543637}, doi = {10.1093/cercor/bhz117}, issn = {1047-3211}, year = {2019}, date = {2019-08-01}, journal = {Cerebral Cortex}, pages = {1--10}, abstract = {The striatum has long been associated with cognitive functions, but the mechanisms behind this are still unclear. Here we tested a new hypothesis that the striatum contributes to executive function (EF) by strengthening cortico-cortical connections. Striatal connectivity was evaluated by measuring the resting-state functional connectivity between ventral and dorsal striatum in 570 individuals, aged 3–20 years. Using structural equation modeling, we found that inter-individual differences in striatal connectivity had an indirect effect (via fronto-parietal functional connectivity) and a direct effect on a compound EF measure of working memory, inhibition, and set-shifting/flexibility. The effect of fronto-parietal connectivity on cognition did not depend on age: the influence was as strong in older as younger children. In contrast, striatal connectivity was closely related to changes in cognitive ability during childhood development, suggesting a specific role of the striatum in cognitive plasticity. These results support a new principle for striatal functioning, according to which striatum promotes cognitive development by strengthening of cortico-cortical connectivity.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The striatum has long been associated with cognitive functions, but the mechanisms behind this are still unclear. Here we tested a new hypothesis that the striatum contributes to executive function (EF) by strengthening cortico-cortical connections. Striatal connectivity was evaluated by measuring the resting-state functional connectivity between ventral and dorsal striatum in 570 individuals, aged 3–20 years. Using structural equation modeling, we found that inter-individual differences in striatal connectivity had an indirect effect (via fronto-parietal functional connectivity) and a direct effect on a compound EF measure of working memory, inhibition, and set-shifting/flexibility. The effect of fronto-parietal connectivity on cognition did not depend on age: the influence was as strong in older as younger children. In contrast, striatal connectivity was closely related to changes in cognitive ability during childhood development, suggesting a specific role of the striatum in cognitive plasticity. These results support a new principle for striatal functioning, according to which striatum promotes cognitive development by strengthening of cortico-cortical connectivity. Close https://academic.oup.com/cercor/advance-article/doi/10.1093/cercor/bhz117/554363[...] doi:10.1093/cercor/bhz117 Close
	C Shawn Green, Daphne Bavelier, Arthur F Kramer, Sophia Vinogradov, Ulrich Ansorge, Karlene K Ball, Ulrike Bingel, Jason M Chein, Lorenza S Colzato, Jerri D Edwards, Andrea Facoetti, Adam Gazzaley, Susan E Gathercole, Paolo Ghisletta, Simone Gori, Isabela Granic, Charles H Hillman, Bernhard Hommel, Susanne M Jaeggi, Philipp Kanske, Julia Karbach, Alan Kingstone, Matthias Kliegel, Torkel Klingberg, Simone Kühn, Dennis M Levi, Richard E Mayer, Anne Collins McLaughlin, Danielle S McNamara, Martha Clare Morris, Mor Nahum, Nora S Newcombe, Rogerio Panizzutti, Ruchika Shaurya Prakash, Albert Rizzo, Torsten Schubert, Aaron R Seitz, Sarah J Short, Ilina Singh, James D Slotta, Tilo Strobach, Michael S C Thomas, Elizabeth Tipton, Xin Tong, Haley A Vlach, Julie Loebach Wetherell, Anna Wexler, Claudia M Witt Improving Methodological Standards in Behavioral Interventions for Cognitive Enhancement Journal Article Journal of Cognitive Enhancement, 3 (1), pp. 2–29, 2019, ISSN: 2509-3290. Abstract \| Links @article{ShawnGreen2019, title = {Improving Methodological Standards in Behavioral Interventions for Cognitive Enhancement}, author = {C {Shawn Green} and Daphne Bavelier and Arthur F Kramer and Sophia Vinogradov and Ulrich Ansorge and Karlene K Ball and Ulrike Bingel and Jason M Chein and Lorenza S Colzato and Jerri D Edwards and Andrea Facoetti and Adam Gazzaley and Susan E Gathercole and Paolo Ghisletta and Simone Gori and Isabela Granic and Charles H Hillman and Bernhard Hommel and Susanne M Jaeggi and Philipp Kanske and Julia Karbach and Alan Kingstone and Matthias Kliegel and Torkel Klingberg and Simone Kühn and Dennis M Levi and Richard E Mayer and Anne Collins McLaughlin and Danielle S McNamara and Martha Clare Morris and Mor Nahum and Nora S Newcombe and Rogerio Panizzutti and Ruchika Shaurya Prakash and Albert Rizzo and Torsten Schubert and Aaron R Seitz and Sarah J Short and Ilina Singh and James D Slotta and Tilo Strobach and Michael S C Thomas and Elizabeth Tipton and Xin Tong and Haley A Vlach and Julie Loebach Wetherell and Anna Wexler and Claudia M Witt}, url = {http://link.springer.com/10.1007/s41465-018-0115-y}, doi = {10.1007/s41465-018-0115-y}, issn = {2509-3290}, year = {2019}, date = {2019-03-01}, journal = {Journal of Cognitive Enhancement}, volume = {3}, number = {1}, pages = {2--29}, publisher = {Springer International Publishing}, abstract = {There is substantial interest in the possibility that cognitive skills can be improved by dedicated behavioral training. Yet despite the large amount of work being conducted in this domain, there is not an explicit and widely agreed upon consensus around the best methodological practices. This document seeks to fill this gap. We start from the perspective that there are many types of studies that are important in this domain—e.g., feasibility, mechanistic, efficacy, and effectiveness. These studies have fundamentally different goals, and, as such, the best-practice methods to meet those goals will also differ. We thus make suggestions in topics ranging from the design and implementation of control groups, to reporting of results, to dissemination and communication, taking the perspective that the best practices are not necessarily uniform across all study types. We also explicitly recognize and discuss the fact that there are methodological issues around which we currently lack the theoretical and/or empirical foundation to determine best practices (e.g., as pertains to assessing participant expectations). For these, we suggest important routes forward, including greater interdisciplinary collaboration with individuals from domains that face related concerns. Our hope is that these recommendations will greatly increase the rate at which science in this domain advances.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close There is substantial interest in the possibility that cognitive skills can be improved by dedicated behavioral training. Yet despite the large amount of work being conducted in this domain, there is not an explicit and widely agreed upon consensus around the best methodological practices. This document seeks to fill this gap. We start from the perspective that there are many types of studies that are important in this domain—e.g., feasibility, mechanistic, efficacy, and effectiveness. These studies have fundamentally different goals, and, as such, the best-practice methods to meet those goals will also differ. We thus make suggestions in topics ranging from the design and implementation of control groups, to reporting of results, to dissemination and communication, taking the perspective that the best practices are not necessarily uniform across all study types. We also explicitly recognize and discuss the fact that there are methodological issues around which we currently lack the theoretical and/or empirical foundation to determine best practices (e.g., as pertains to assessing participant expectations). For these, we suggest important routes forward, including greater interdisciplinary collaboration with individuals from domains that face related concerns. Our hope is that these recommendations will greatly increase the rate at which science in this domain advances. Close http://link.springer.com/10.1007/s41465-018-0115-y doi:10.1007/s41465-018-0115-y Close
	Lotfi Khemiri, Christoffer Brynte, Angela Stunkel, Torkel Klingberg, Nitya Jayaram-Lindström Working Memory Training in Alcohol Use Disorder: A Randomized Controlled Trial Journal Article Alcoholism: Clinical and Experimental Research, 43 (1), pp. 135–146, 2019, ISSN: 01456008. Abstract \| Links @article{Khemiri2019, title = {Working Memory Training in Alcohol Use Disorder: A Randomized Controlled Trial}, author = {Lotfi Khemiri and Christoffer Brynte and Angela Stunkel and Torkel Klingberg and Nitya Jayaram-Lindström}, url = {http://doi.wiley.com/10.1111/acer.13910}, doi = {10.1111/acer.13910}, issn = {01456008}, year = {2019}, date = {2019-01-01}, journal = {Alcoholism: Clinical and Experimental Research}, volume = {43}, number = {1}, pages = {135--146}, abstract = {BACKGROUND: Alcohol use disorder (AUD) is associated with cognitive deficits such as impaired executive functions, which are hypothesized to contribute to the progression of the disease and worsen treatment outcome. Training of working memory (WM) to improve cognitive functions and thereby reduce alcohol use has been proposed as a novel treatment strategy. METHODS: Patients with AUD (n = 50) who were recruited to an outpatient addiction clinic were randomized to receive 5 weeks of active WM training or control training. Participants had weekly follow-up visits, and all cognitive training sessions were done online at home. Primary outcomes were WM function and change in self-reported heavy drinking. Secondary outcomes were craving, other drinking outcomes, and performance on a range of neuropsychological tasks from the Cambridge Neuropsychological Test Automated Battery. RESULTS: The active training group demonstrated a significantly greater improvement in verbal WM compared with the control group. No statistically significant effect of training was found on the primary drinking outcome, but a trend was observed indicating that WM training reduces the number of drinks per drinking occasion. WM training had no statistically significant effect on any of the other neuropsychological tasks. CONCLUSIONS: Cognitive training can improve WM function in individuals with AUD, suggesting that such interventions are feasible to administer in this patient population. The results do not support an effect of WM training on heavy drinking or transfer effects to other cognitive domains. Future studies should evaluate WM training as an adjunct to evidence-based treatments for AUD to assess potential synergistic effects.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close BACKGROUND: Alcohol use disorder (AUD) is associated with cognitive deficits such as impaired executive functions, which are hypothesized to contribute to the progression of the disease and worsen treatment outcome. Training of working memory (WM) to improve cognitive functions and thereby reduce alcohol use has been proposed as a novel treatment strategy. METHODS: Patients with AUD (n = 50) who were recruited to an outpatient addiction clinic were randomized to receive 5 weeks of active WM training or control training. Participants had weekly follow-up visits, and all cognitive training sessions were done online at home. Primary outcomes were WM function and change in self-reported heavy drinking. Secondary outcomes were craving, other drinking outcomes, and performance on a range of neuropsychological tasks from the Cambridge Neuropsychological Test Automated Battery. RESULTS: The active training group demonstrated a significantly greater improvement in verbal WM compared with the control group. No statistically significant effect of training was found on the primary drinking outcome, but a trend was observed indicating that WM training reduces the number of drinks per drinking occasion. WM training had no statistically significant effect on any of the other neuropsychological tasks. CONCLUSIONS: Cognitive training can improve WM function in individuals with AUD, suggesting that such interventions are feasible to administer in this patient population. The results do not support an effect of WM training on heavy drinking or transfer effects to other cognitive domains. Future studies should evaluate WM training as an adjunct to evidence-based treatments for AUD to assess potential synergistic effects. Close http://doi.wiley.com/10.1111/acer.13910 doi:10.1111/acer.13910 Close
2018
	Martin Hassler Hallstedt, Torkel Klingberg, Ata Ghaderi Short and long-term effects of a mathematics tablet intervention for low performing second graders. Journal Article Journal of Educational Psychology, 110 (8), pp. 1127–1148, 2018, ISSN: 1939-2176. Abstract \| Links @article{Hallstedt2018, title = {Short and long-term effects of a mathematics tablet intervention for low performing second graders.}, author = {Martin {Hassler Hallstedt} and Torkel Klingberg and Ata Ghaderi}, url = {http://doi.apa.org/getdoi.cfm?doi=10.1037/edu0000264}, doi = {10.1037/edu0000264}, issn = {1939-2176}, year = {2018}, date = {2018-11-01}, journal = {Journal of Educational Psychology}, volume = {110}, number = {8}, pages = {1127--1148}, abstract = {Using a randomized placebo controlled design, we examined the direct and follow-up effects (at 6 and 12 months) of a mathematics tablet intervention. Math training focused primarily on basic arithmetic (addition and subtraction facts up to 12), and secondarily on number knowledge and word problems. We investigated the moderating effects of IQ and socioeconomic factors, and additive effects of working memory (WM) training. A representative sample of 283 low performing second-grade students were randomly assigned to control ( n = 52), reading placebo ( n = 78), math intervention (MA; n = 76), or math plus WM training (MA + WM; n = 77). Both math conditions scored significantly higher than control and placebo on the posttest of basic arithmetic, but not on arithmetic transfer and problem solving. WM training did not show additive effects. Given the virtually identical patterns, we collapsed the control and placebo, respectively, MA and MA + WM conditions. The collapsed MA/MA + WM condition demonstrated significant medium-sized effects ( d = 0.53–0.67) on basic arithmetic compared with the collapsed control/placebo condition at posttest. There was a fadeout of effects at 6-month follow-up ( d = 0.18–0.28), that declined further at 12 months ( d = 0.03–0.13). IQ was a significant moderator of direct and long-term effects on addition up to 12 and subtraction up to 18, where students with lower IQ benefitted more than higher IQ students. Socioeconomic factors did not moderate outcome. The intervention effectively improved basic arithmetic among low performing second graders. Although the effects waned at 6-month follow-up, there was some indication that children with lower IQ demonstrated sustained gains. (PsycINFO Database Record (c) 2018 APA, all rights reserved) (Source: journal abstract) Impact statementEducational Impact and Implications Statement: This study shows that adaptive math training on tablet can help low performing 8-year-olds catch up about half a year of schooling in critical math skills. Students with lower IQ benefitted in particular and made long-term gains 12 months after training finished. Additional short-term memory training did not result in further math improvement. Because math is a strong predictor of later school achievement, these findings highlight the potential of well-designed adaptive teaching on tablets to significantly improve students' success at school. Evidence-based programs covering the bulk of elementary math might be widely spread, potentially at a low cost. (PsycINFO Database Record (c) 2018 APA, all rights reserved)}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Using a randomized placebo controlled design, we examined the direct and follow-up effects (at 6 and 12 months) of a mathematics tablet intervention. Math training focused primarily on basic arithmetic (addition and subtraction facts up to 12), and secondarily on number knowledge and word problems. We investigated the moderating effects of IQ and socioeconomic factors, and additive effects of working memory (WM) training. A representative sample of 283 low performing second-grade students were randomly assigned to control ( n = 52), reading placebo ( n = 78), math intervention (MA; n = 76), or math plus WM training (MA + WM; n = 77). Both math conditions scored significantly higher than control and placebo on the posttest of basic arithmetic, but not on arithmetic transfer and problem solving. WM training did not show additive effects. Given the virtually identical patterns, we collapsed the control and placebo, respectively, MA and MA + WM conditions. The collapsed MA/MA + WM condition demonstrated significant medium-sized effects ( d = 0.53–0.67) on basic arithmetic compared with the collapsed control/placebo condition at posttest. There was a fadeout of effects at 6-month follow-up ( d = 0.18–0.28), that declined further at 12 months ( d = 0.03–0.13). IQ was a significant moderator of direct and long-term effects on addition up to 12 and subtraction up to 18, where students with lower IQ benefitted more than higher IQ students. Socioeconomic factors did not moderate outcome. The intervention effectively improved basic arithmetic among low performing second graders. Although the effects waned at 6-month follow-up, there was some indication that children with lower IQ demonstrated sustained gains. (PsycINFO Database Record (c) 2018 APA, all rights reserved) (Source: journal abstract) Impact statementEducational Impact and Implications Statement: This study shows that adaptive math training on tablet can help low performing 8-year-olds catch up about half a year of schooling in critical math skills. Students with lower IQ benefitted in particular and made long-term gains 12 months after training finished. Additional short-term memory training did not result in further math improvement. Because math is a strong predictor of later school achievement, these findings highlight the potential of well-designed adaptive teaching on tablets to significantly improve students' success at school. Evidence-based programs covering the bulk of elementary math might be widely spread, potentially at a low cost. (PsycINFO Database Record (c) 2018 APA, all rights reserved) Close http://doi.apa.org/getdoi.cfm?doi=10.1037/edu0000264 doi:10.1037/edu0000264 Close
	Federico Nemmi, Margot A Schel, Torkel Klingberg Connectivity of the Human Number Form Area Reveals Development of a Cortical Network for Mathematics Journal Article Frontiers in Human Neuroscience, 12 (November), pp. 1–15, 2018, ISSN: 1662-5161. Abstract \| Links @article{Nemmi2018a, title = {Connectivity of the Human Number Form Area Reveals Development of a Cortical Network for Mathematics}, author = {Federico Nemmi and Margot A Schel and Torkel Klingberg}, url = {https://www.frontiersin.org/article/10.3389/fnhum.2018.00465/full}, doi = {10.3389/fnhum.2018.00465}, issn = {1662-5161}, year = {2018}, date = {2018-11-01}, journal = {Frontiers in Human Neuroscience}, volume = {12}, number = {November}, pages = {1--15}, abstract = {The adult brain contains cortical areas thought to be specialized for the analysis of numbers (the putative number form area, NFA) and letters (the visual word form area, VWFA). Although functional development of the VWFA has been investigated, it is largely unknown when and how the NFA becomes specialized and connected to the rest of the brain. One hypothesis is that NFA and VWFA derive their special functions through differential connectivity, but the development of this differential connectivity has not been shown. Here we mapped the resting state connectivity of NFA and VWFA to the rest of the brain in a large sample (n = 437) of individuals (age 3.2 – 21 years). We show that within NFA-math network and within VWFA-reading network the strength of connectivity increases with age. The right NFA is significantly connected to the right intraparietal cortex already at the earliest age tested (age 3), before formal mathematical education has begun. This connection might support or enable an early understanding of magnitude or numerosity In contrast, the functional connectivity from NFA to the left anterior intraparietal cortex and to the right dorsolateral prefrontal cortex is not different from the functional connectivity of VWFA to these regions until around 12-14 years of age. The increase in connectivity to these regions was associated with a gradual increase in mathematical ability in an independent sample. In contrast, VWFA connects significantly to Broca's region around age 6, and this connectivity is correlated with reading ability. These results show how the differential connectivity of the networks for mathematics and reading slowly emerges through years of training and education.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The adult brain contains cortical areas thought to be specialized for the analysis of numbers (the putative number form area, NFA) and letters (the visual word form area, VWFA). Although functional development of the VWFA has been investigated, it is largely unknown when and how the NFA becomes specialized and connected to the rest of the brain. One hypothesis is that NFA and VWFA derive their special functions through differential connectivity, but the development of this differential connectivity has not been shown. Here we mapped the resting state connectivity of NFA and VWFA to the rest of the brain in a large sample (n = 437) of individuals (age 3.2 – 21 years). We show that within NFA-math network and within VWFA-reading network the strength of connectivity increases with age. The right NFA is significantly connected to the right intraparietal cortex already at the earliest age tested (age 3), before formal mathematical education has begun. This connection might support or enable an early understanding of magnitude or numerosity In contrast, the functional connectivity from NFA to the left anterior intraparietal cortex and to the right dorsolateral prefrontal cortex is not different from the functional connectivity of VWFA to these regions until around 12-14 years of age. The increase in connectivity to these regions was associated with a gradual increase in mathematical ability in an independent sample. In contrast, VWFA connects significantly to Broca's region around age 6, and this connectivity is correlated with reading ability. These results show how the differential connectivity of the networks for mathematics and reading slowly emerges through years of training and education. Close https://www.frontiersin.org/article/10.3389/fnhum.2018.00465/full doi:10.3389/fnhum.2018.00465 Close
	N Kalnak, S Stamouli, M Peyrard-Janvid, I Rabkina, M Becker, T Klingberg, J Kere, H Forssberg, K Tammimies Enrichment of rare copy number variation in children with developmental language disorder Journal Article Clinical Genetics, 94 (3-4), pp. 313–320, 2018, ISSN: 00099163. Abstract \| Links @article{Kalnak2018, title = {Enrichment of rare copy number variation in children with developmental language disorder}, author = {N Kalnak and S Stamouli and M Peyrard-Janvid and I Rabkina and M Becker and T Klingberg and J Kere and H Forssberg and K Tammimies}, url = {http://doi.wiley.com/10.1111/cge.13389}, doi = {10.1111/cge.13389}, issn = {00099163}, year = {2018}, date = {2018-10-01}, journal = {Clinical Genetics}, volume = {94}, number = {3-4}, pages = {313--320}, abstract = {Developmental Language Disorder (DLD) is a common neurodevelopmental disorder with largely unknown etiology. Rare copy number variants (CNVs) have been implicated in the genetic architecture of other neurodevelopmental disorders (NDDs) which have led to clinical genetic testing recommendations for these disorders; however, the evidence is still lacking for DLD. We analyzed rare and de novo CNVs in 58 probands with severe DLD, their 159 family members and 76 Swedish typically developing children using high-resolution microarray. DLD probands had larger rare CNVs as measured by total length (p=0.05), and average length (p=0.04). Additionally, the rate of rare CNVs overlapping coding genes was increased (p=0.03 and p=0.01) and in average more genes were affected (p=0.006 and p=0.03) in the probands and their siblings, respectively. De novo CNVs were found in 4.8% DLD probands (2/42) and 2.4% (1/42) siblings. Clinically significant CNVs or chromosomal anomalies were found in 6.9% (4/58) of the probands of which two carried 16p11.2 deletions. We provide further evidence that rare CNVs contribute to the etiology of DLD in loci that overlap with other NDDs. Based on our results and earlier literature, families with DLD should be offered molecular genetic testing as a routine in their clinical follow-up. This article is protected by copyright. All rights reserved.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Developmental Language Disorder (DLD) is a common neurodevelopmental disorder with largely unknown etiology. Rare copy number variants (CNVs) have been implicated in the genetic architecture of other neurodevelopmental disorders (NDDs) which have led to clinical genetic testing recommendations for these disorders; however, the evidence is still lacking for DLD. We analyzed rare and de novo CNVs in 58 probands with severe DLD, their 159 family members and 76 Swedish typically developing children using high-resolution microarray. DLD probands had larger rare CNVs as measured by total length (p=0.05), and average length (p=0.04). Additionally, the rate of rare CNVs overlapping coding genes was increased (p=0.03 and p=0.01) and in average more genes were affected (p=0.006 and p=0.03) in the probands and their siblings, respectively. De novo CNVs were found in 4.8% DLD probands (2/42) and 2.4% (1/42) siblings. Clinically significant CNVs or chromosomal anomalies were found in 6.9% (4/58) of the probands of which two carried 16p11.2 deletions. We provide further evidence that rare CNVs contribute to the etiology of DLD in loci that overlap with other NDDs. Based on our results and earlier literature, families with DLD should be offered molecular genetic testing as a routine in their clinical follow-up. This article is protected by copyright. All rights reserved. Close http://doi.wiley.com/10.1111/cge.13389 doi:10.1111/cge.13389 Close
	Fahimeh Darki, Torkel Klingberg Functional differentiation between convergence and non-convergence zones of the striatum in children Journal Article NeuroImage, 173 (January), pp. 384–393, 2018, ISSN: 10538119. Abstract \| Links @article{Darki2018, title = {Functional differentiation between convergence and non-convergence zones of the striatum in children}, author = {Fahimeh Darki and Torkel Klingberg}, url = {https://linkinghub.elsevier.com/retrieve/pii/S1053811918301617}, doi = {10.1016/j.neuroimage.2018.02.054}, issn = {10538119}, year = {2018}, date = {2018-06-01}, journal = {NeuroImage}, volume = {173}, number = {January}, pages = {384--393}, abstract = {Most cortical areas send projections to the striatum. In some parts of the striatum, the connections converge from several cortical areas. It is unknown whether the convergence and non-convergence zones of the striatum differ functionally. Here, we used diffusion-weighted magnetic resonance imaging and probabilistic fiber tracking to parcellate the striatum based on its connections to dorsolateral prefrontal, parietal and orbitofrontal cortices in two different datasets (children aged 6–7 years and adults). In both samples, quantitative susceptibility mapping (QSM) values were significantly correlated with working memory (WM) in convergence zones, but not in non-convergence zones. In children, this was also true for mean diffusivity, MD. The association of MD to WM specifically in the convergent zone was replicated in the Pediatric Imaging, Neurocognition, and Genetics (PING) dataset for 135 children aged 6–9 years. QSM data was not available in the PING dataset, and the association to QSM still needs to be replicated. These results suggest that connectivity-based segments of the striatum exhibit functionally different characteristics. The association between convergence zones and WM performance might relate to a role in integrating and coordinating activity in different cortical areas.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Most cortical areas send projections to the striatum. In some parts of the striatum, the connections converge from several cortical areas. It is unknown whether the convergence and non-convergence zones of the striatum differ functionally. Here, we used diffusion-weighted magnetic resonance imaging and probabilistic fiber tracking to parcellate the striatum based on its connections to dorsolateral prefrontal, parietal and orbitofrontal cortices in two different datasets (children aged 6–7 years and adults). In both samples, quantitative susceptibility mapping (QSM) values were significantly correlated with working memory (WM) in convergence zones, but not in non-convergence zones. In children, this was also true for mean diffusivity, MD. The association of MD to WM specifically in the convergent zone was replicated in the Pediatric Imaging, Neurocognition, and Genetics (PING) dataset for 135 children aged 6–9 years. QSM data was not available in the PING dataset, and the association to QSM still needs to be replicated. These results suggest that connectivity-based segments of the striatum exhibit functionally different characteristics. The association between convergence zones and WM performance might relate to a role in integrating and coordinating activity in different cortical areas. Close https://linkinghub.elsevier.com/retrieve/pii/S1053811918301617 doi:10.1016/j.neuroimage.2018.02.054 Close
	F Nemmi, C Nymberg, F Darki, T Banaschewski, A L W Bokde, C Büchel, H Flor, V Frouin, H Garavan, P Gowland, A Heinz, J -L Martinot, F Nees, T Paus, M N Smolka, T W Robbins, G Schumann, Torkel Klingberg Interaction between striatal volume and DAT1 polymorphism predicts working memory development during adolescence Journal Article Developmental Cognitive Neuroscience, 30 (February), pp. 191–199, 2018, ISSN: 18789293. Abstract \| Links @article{Nemmi2018b, title = {Interaction between striatal volume and DAT1 polymorphism predicts working memory development during adolescence}, author = {F Nemmi and C Nymberg and F Darki and T Banaschewski and A L W Bokde and C Büchel and H Flor and V Frouin and H Garavan and P Gowland and A Heinz and J -L Martinot and F Nees and T Paus and M N Smolka and T W Robbins and G Schumann and Torkel Klingberg}, url = {https://doi.org/10.1016/j.dcn.2018.03.006 https://linkinghub.elsevier.com/retrieve/pii/S1878929317301536}, doi = {10.1016/j.dcn.2018.03.006}, issn = {18789293}, year = {2018}, date = {2018-04-01}, journal = {Developmental Cognitive Neuroscience}, volume = {30}, number = {February}, pages = {191--199}, publisher = {Elsevier}, abstract = {There is considerable inter-individual variability in the rate at which working memory (WM) develops during childhood and adolescence, but the neural and genetic basis for these differences are poorly understood. Dopamine-related genes, striatal activation and morphology have been associated with increased WM capacity after training. Here we tested the hypothesis that these factors would also explain some of the inter-individual differences in the rate of WM development. We measured WM performance in 487 healthy subjects twice: at age 14 and 19. At age 14 subjects underwent a structural MRI scan, and genotyping of five single nucleotide polymorphisms (SNPs) in or close to the dopamine genes DRD2, DAT-1 and COMT, which have previously been associated with gains in WM after WM training. We then analyzed which biological factors predicted the rate of increase in WM between ages 14 and 19. We found a significant interaction between putamen size and DAT1/SLC6A3 rs40184 polymorphism, such that TC heterozygotes with a larger putamen at age 14 showed greater WM improvement at age 19. The effect of the DAT1 polymorphism on WM development was exerted in interaction with striatal morphology. These results suggest that development of WM partially share neuro-physiological mechanism with training-induced plasticity.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close There is considerable inter-individual variability in the rate at which working memory (WM) develops during childhood and adolescence, but the neural and genetic basis for these differences are poorly understood. Dopamine-related genes, striatal activation and morphology have been associated with increased WM capacity after training. Here we tested the hypothesis that these factors would also explain some of the inter-individual differences in the rate of WM development. We measured WM performance in 487 healthy subjects twice: at age 14 and 19. At age 14 subjects underwent a structural MRI scan, and genotyping of five single nucleotide polymorphisms (SNPs) in or close to the dopamine genes DRD2, DAT-1 and COMT, which have previously been associated with gains in WM after WM training. We then analyzed which biological factors predicted the rate of increase in WM between ages 14 and 19. We found a significant interaction between putamen size and DAT1/SLC6A3 rs40184 polymorphism, such that TC heterozygotes with a larger putamen at age 14 showed greater WM improvement at age 19. The effect of the DAT1 polymorphism on WM development was exerted in interaction with striatal morphology. These results suggest that development of WM partially share neuro-physiological mechanism with training-induced plasticity. Close https://doi.org/10.1016/j.dcn.2018.03.006 https://linkinghub.elsevier.com/retrie[...] doi:10.1016/j.dcn.2018.03.006 Close
2017
	Fahimeh Darki, Satu Massinen, Elina Salmela, Hans Matsson, Myriam Peyrard-Janvid, Torkel Klingberg, Juha Kere Human ROBO1 regulates white matter structure in corpus callosum Journal Article Brain Structure and Function, 222 (2), pp. 707–716, 2017, ISSN: 18632661. Abstract \| Links @article{Darki2017, title = {Human ROBO1 regulates white matter structure in corpus callosum}, author = {Fahimeh Darki and Satu Massinen and Elina Salmela and Hans Matsson and Myriam Peyrard-Janvid and Torkel Klingberg and Juha Kere}, doi = {10.1007/s00429-016-1240-y}, issn = {18632661}, year = {2017}, date = {2017-01-01}, journal = {Brain Structure and Function}, volume = {222}, number = {2}, pages = {707--716}, publisher = {Springer Berlin Heidelberg}, abstract = {textcopyright 2016, The Author(s). The axon guidance receptor, Robo1, controls the pathfinding of callosal axons in mice. To determine whether the orthologous ROBO1 gene is involved in callosal development also in humans, we studied polymorphisms in the ROBO1 gene and variation in the white matter structure in the corpus callosum using both structural magnetic resonance imaging and diffusion tensor magnetic resonance imaging. We found that five polymorphisms in the regulatory region of ROBO1 were associated with white matter density in the posterior part of the corpus callosum pathways. One of the polymorphisms, rs7631357, was also significantly associated with the probability of connections to the parietal cortical regions. Our results demonstrate that human ROBO1 may be involved in the regulation of the structure and connectivity of posterior part of corpus callosum.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close textcopyright 2016, The Author(s). The axon guidance receptor, Robo1, controls the pathfinding of callosal axons in mice. To determine whether the orthologous ROBO1 gene is involved in callosal development also in humans, we studied polymorphisms in the ROBO1 gene and variation in the white matter structure in the corpus callosum using both structural magnetic resonance imaging and diffusion tensor magnetic resonance imaging. We found that five polymorphisms in the regulatory region of ROBO1 were associated with white matter density in the posterior part of the corpus callosum pathways. One of the polymorphisms, rs7631357, was also significantly associated with the probability of connections to the parietal cortical regions. Our results demonstrate that human ROBO1 may be involved in the regulation of the structure and connectivity of posterior part of corpus callosum. Close doi:10.1007/s00429-016-1240-y Close
	Elisabet Einarsdottir, Myriam Peyrard-Janvid, Fahimeh Darki, Jetro J Tuulari, Harri Merisaari, Linnea Karlsson, Noora M Scheinin, Jani Saunavaara, Riitta Parkkola, Katri Kantojärvi, Antti Jussi Ämmälä, Nancy Yiu-Lin Yu, Hans Matsson, Jaana Nopola-Hemmi, Hasse Karlsson, Tiina Paunio, Torkel Klingberg, Eira Leinonen, Juha Kere Identification of NCAN as a candidate gene for developmental dyslexia Journal Article Scientific Reports, 7 (1), pp. 1–11, 2017, ISSN: 20452322. Abstract \| Links @article{Einarsdottir2017, title = {Identification of NCAN as a candidate gene for developmental dyslexia}, author = {Elisabet Einarsdottir and Myriam Peyrard-Janvid and Fahimeh Darki and Jetro J Tuulari and Harri Merisaari and Linnea Karlsson and Noora M Scheinin and Jani Saunavaara and Riitta Parkkola and Katri Kantojärvi and Antti Jussi Ämmälä and Nancy {Yiu-Lin Yu} and Hans Matsson and Jaana Nopola-Hemmi and Hasse Karlsson and Tiina Paunio and Torkel Klingberg and Eira Leinonen and Juha Kere}, doi = {10.1038/s41598-017-10175-7}, issn = {20452322}, year = {2017}, date = {2017-01-01}, journal = {Scientific Reports}, volume = {7}, number = {1}, pages = {1--11}, abstract = {A whole-genome linkage analysis in a Finnish pedigree of eight cases with developmental dyslexia (DD) revealed several regions shared by the affected individuals. Analysis of coding variants from two affected individuals identified rs146011974G textgreater A (Ala1039Thr), a rare variant within the NCAN gene co-segregating with DD in the pedigree. This variant prompted us to consider this gene as a putative candidate for DD. The RNA expression pattern of the NCAN gene in human tissues was highly correlated (R textgreater 0.8) with that of the previously suggested DD susceptibility genes KIAA0319, CTNND2, CNTNAP2 and GRIN2B. We investigated the association of common variation in NCAN to brain structures in two data sets: young adults (Brainchild study, Sweden) and infants (FinnBrain study, Finland). In young adults, we found associations between a common genetic variant in NCAN, rs1064395, and white matter volume in the left and right temporoparietal as well as the left inferior frontal brain regions. In infants, this same variant was found to be associated with cingulate and prefrontal grey matter volumes. Our results suggest NCAN as a new candidate gene for DD and indicate that NCAN variants affect brain structure.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close A whole-genome linkage analysis in a Finnish pedigree of eight cases with developmental dyslexia (DD) revealed several regions shared by the affected individuals. Analysis of coding variants from two affected individuals identified rs146011974G textgreater A (Ala1039Thr), a rare variant within the NCAN gene co-segregating with DD in the pedigree. This variant prompted us to consider this gene as a putative candidate for DD. The RNA expression pattern of the NCAN gene in human tissues was highly correlated (R textgreater 0.8) with that of the previously suggested DD susceptibility genes KIAA0319, CTNND2, CNTNAP2 and GRIN2B. We investigated the association of common variation in NCAN to brain structures in two data sets: young adults (Brainchild study, Sweden) and infants (FinnBrain study, Finland). In young adults, we found associations between a common genetic variant in NCAN, rs1064395, and white matter volume in the left and right temporoparietal as well as the left inferior frontal brain regions. In infants, this same variant was found to be associated with cingulate and prefrontal grey matter volumes. Our results suggest NCAN as a new candidate gene for DD and indicate that NCAN variants affect brain structure. Close doi:10.1038/s41598-017-10175-7 Close
	Annie Möller, Federico Nemmi, Kim Karlsson, Torkel Klingberg Transcranial Electric Stimulation Can Impair Gains during Working Memory Training and Affects the Resting State Connectivity Journal Article Frontiers in Human Neuroscience, 11 (July), pp. 1–12, 2017. Abstract \| Links @article{Moller2017, title = {Transcranial Electric Stimulation Can Impair Gains during Working Memory Training and Affects the Resting State Connectivity}, author = {Annie Möller and Federico Nemmi and Kim Karlsson and Torkel Klingberg}, doi = {10.3389/fnhum.2017.00364}, year = {2017}, date = {2017-01-01}, journal = {Frontiers in Human Neuroscience}, volume = {11}, number = {July}, pages = {1--12}, abstract = {Transcranial electric stimulation (tES) is a promising technique that has been shown to improve working memory (WM) performance and enhance the effect of cognitive training. However, experimental set up and electrode placement are not always determined based on neurofunctional knowledge about WM, leading to inconsistent results. Additional research on the effects of tES grounded on neurofunctional evidence is therefore necessary. 60 young, healthy, volunteers, assigned to 6 different groups, participated in 5 days of stimulation or sham treatment. 25 of these subjects also participated in MRI acquisition. We performed 3 experiments: In the first one we evaluated tES using either direct current stimulation (tDCS) with bilateral stimulation of the frontal or parietal lobe; in the second one we used the same tDCS protocol with a different electrode placement (i.e. supraorbital cathode); in the third one we used alternating currents (tACS) of 35 Hz, applied bilaterally to either the frontal or parietal lobes. The behavioral outcome measure was the WM capacity (i.e. number of remembered spatial position) during the 5 days of training. In a subsample of subjects we evaluated the neural effects of tDCS by measuring resting state connectivity with functional MRI, before and after the 5 days of tDCS and visuo-spatial WM training. We found a significant impairment of WM training-related gains associated with parietal tACS and frontal tDCS. Five days of tDCS stimulation was also associated with significant change in resting state connectivity revealed by multivariate pattern analysis (MVPA). None of the stimulation paradigms resulted in improved WM performance or enhanced WM training gains. These results show that tES can have negative effects on cognitive plasticity and affect resting-state functional connectivity.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Transcranial electric stimulation (tES) is a promising technique that has been shown to improve working memory (WM) performance and enhance the effect of cognitive training. However, experimental set up and electrode placement are not always determined based on neurofunctional knowledge about WM, leading to inconsistent results. Additional research on the effects of tES grounded on neurofunctional evidence is therefore necessary. 60 young, healthy, volunteers, assigned to 6 different groups, participated in 5 days of stimulation or sham treatment. 25 of these subjects also participated in MRI acquisition. We performed 3 experiments: In the first one we evaluated tES using either direct current stimulation (tDCS) with bilateral stimulation of the frontal or parietal lobe; in the second one we used the same tDCS protocol with a different electrode placement (i.e. supraorbital cathode); in the third one we used alternating currents (tACS) of 35 Hz, applied bilaterally to either the frontal or parietal lobes. The behavioral outcome measure was the WM capacity (i.e. number of remembered spatial position) during the 5 days of training. In a subsample of subjects we evaluated the neural effects of tDCS by measuring resting state connectivity with functional MRI, before and after the 5 days of tDCS and visuo-spatial WM training. We found a significant impairment of WM training-related gains associated with parietal tACS and frontal tDCS. Five days of tDCS stimulation was also associated with significant change in resting state connectivity revealed by multivariate pattern analysis (MVPA). None of the stimulation paradigms resulted in improved WM performance or enhanced WM training gains. These results show that tES can have negative effects on cognitive plasticity and affect resting-state functional connectivity. Close doi:10.3389/fnhum.2017.00364 Close
	Douglas Sjöwall, Mattias Hertz, Torkel Klingberg No long-term effect of physical activity intervention on working memory or arithmetic in preadolescents Journal Article Frontiers in Psychology, 8 (AUG), pp. 1–10, 2017, ISSN: 16641078. Abstract \| Links @article{Sjowall2017, title = {No long-term effect of physical activity intervention on working memory or arithmetic in preadolescents}, author = {Douglas Sjöwall and Mattias Hertz and Torkel Klingberg}, doi = {10.3389/fpsyg.2017.01342}, issn = {16641078}, year = {2017}, date = {2017-01-01}, journal = {Frontiers in Psychology}, volume = {8}, number = {AUG}, pages = {1--10}, abstract = {We investigate if increased physical activity leads to enhanced working memory capacity and arithmetic performance, in a 2-year school-based intervention in preadolescent children (age 6-13). The active school (n = 228) increased physical activity (aimed at increasing cardiovascular fitness) from 2 to 5 days a week while the control school (n = 242) remained at 2 days. Twice a year, participants performed tests of arithmetic as well as verbal and spatial working memory. They also rated stress with a questionnaire at the start and at the end of the intervention. There was no beneficial development of working memory or arithmetic for the active school as compared to the control school. Furthermore, subgroup analyses revealed no favorable intervention effect for high/low baseline fitness, cognition or grit. Unexpectedly, a significant increase in self-rated stress was detected for the active school and this effect was driven by girls rather than boys and by the younger rather than older children. These results indicate that longtime high intensity physical activity does not lead to a beneficial development of working memory or arithmetic in preadolescent children.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close We investigate if increased physical activity leads to enhanced working memory capacity and arithmetic performance, in a 2-year school-based intervention in preadolescent children (age 6-13). The active school (n = 228) increased physical activity (aimed at increasing cardiovascular fitness) from 2 to 5 days a week while the control school (n = 242) remained at 2 days. Twice a year, participants performed tests of arithmetic as well as verbal and spatial working memory. They also rated stress with a questionnaire at the start and at the end of the intervention. There was no beneficial development of working memory or arithmetic for the active school as compared to the control school. Furthermore, subgroup analyses revealed no favorable intervention effect for high/low baseline fitness, cognition or grit. Unexpectedly, a significant increase in self-rated stress was detected for the active school and this effect was driven by girls rather than boys and by the younger rather than older children. These results indicate that longtime high intensity physical activity does not lead to a beneficial development of working memory or arithmetic in preadolescent children. Close doi:10.3389/fpsyg.2017.01342 Close
	Henrik Ullman, Torkel Klingberg Timing of white matter development determines cognitive abilities at school entry but not in late adolescence Journal Article Cerebral Cortex, 27 (9), pp. 4516–4522, 2017, ISSN: 14602199. Abstract \| Links @article{Ullman2017, title = {Timing of white matter development determines cognitive abilities at school entry but not in late adolescence}, author = {Henrik Ullman and Torkel Klingberg}, doi = {10.1093/cercor/bhw256}, issn = {14602199}, year = {2017}, date = {2017-01-01}, journal = {Cerebral Cortex}, volume = {27}, number = {9}, pages = {4516--4522}, abstract = {The primary aim of this study was to investigate to what degree the age-related white matter development, here called " brain age " , is associated with working memory (WM) and numeric abilities in 6-year-old children. We measured white matter development using diffusion tensor imaging to calculate fractional anisotropy (FA). A " brain age " model was created using multivariate statistics, which described association between FA and age in a sample of 6-to 20-year-old children. This age model was then applied to predict " brain age " in a second sample of 6-year-old children. The predicted brain age correlated with WM performance and numerical ability (NA) (P textless 0.01, P textless 0.05) in the 6-year-old children. More than 50% of the stable variance in WM performance was explained. We found that in children older than 13 years of age, this association between brain age and WM was no longer significant (P textgreater 0.5). The results bear theoretical implications as they suggest that the variability in individual developmental timing strongly affects WM and NA at school start but badly predicts adolescent cognitive functioning. Furthermore, it bears practical implications as one may differentiate maturation lags from persistent low cognitive abilities in school children, complementing cognitive tests.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The primary aim of this study was to investigate to what degree the age-related white matter development, here called " brain age " , is associated with working memory (WM) and numeric abilities in 6-year-old children. We measured white matter development using diffusion tensor imaging to calculate fractional anisotropy (FA). A " brain age " model was created using multivariate statistics, which described association between FA and age in a sample of 6-to 20-year-old children. This age model was then applied to predict " brain age " in a second sample of 6-year-old children. The predicted brain age correlated with WM performance and numerical ability (NA) (P textless 0.01, P textless 0.05) in the 6-year-old children. More than 50% of the stable variance in WM performance was explained. We found that in children older than 13 years of age, this association between brain age and WM was no longer significant (P textgreater 0.5). The results bear theoretical implications as they suggest that the variability in individual developmental timing strongly affects WM and NA at school start but badly predicts adolescent cognitive functioning. Furthermore, it bears practical implications as one may differentiate maturation lags from persistent low cognitive abilities in school children, complementing cognitive tests. Close doi:10.1093/cercor/bhw256 Close
2016
	Margot A Schel, Torkel Klingberg Specialization of the Right Intraparietal Sulcus for Processing Mathematics During Development Journal Article Cerebral Cortex, 27 (9), pp. 4436–4446, 2016, ISSN: 1047-3211. Abstract \| Links @article{Schel2017, title = {Specialization of the Right Intraparietal Sulcus for Processing Mathematics During Development}, author = {Margot A Schel and Torkel Klingberg}, url = {http://cercor.oxfordjournals.org/cgi/doi/10.1093/cercor/bhw246}, doi = {10.1093/cercor/bhw246}, issn = {1047-3211}, year = {2016}, date = {2016-08-01}, journal = {Cerebral Cortex}, volume = {27}, number = {9}, pages = {4436--4446}, abstract = {Mathematical ability, especially perception of numbers and performance of arithmetics, is known to rely on the activation of intraparietal sulcus (IPS). However, reasoning ability and working memory, 2 highly associated abilities also activate partly overlapping regions. Most studies aimed at localizing mathematical function have used group averages, where individual variability is averaged out, thus confounding the anatomical specificity when localizing cognitive functions. Here, we analyze the functional anatomy of the intraparietal cortex by using individual analysis of subregions of IPS based on how they are structurally connected to frontal, parietal, and occipital cortex. Analysis of cortical thickness showed that the right anterior IPS, defined by its connections to the frontal lobe, was associated with both visuospatial working memory, and mathematics in 6-year-old children. This region specialized during development to be specifically related to mathematics, but not visuospatial working memory in adolescents and adults. This could be an example of interactive specialization, where interacting with the environment in combination with interactions between cortical regions leads from a more general role of right anterior IPS in spatial processing, to a specialization of this region for mathematics.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Mathematical ability, especially perception of numbers and performance of arithmetics, is known to rely on the activation of intraparietal sulcus (IPS). However, reasoning ability and working memory, 2 highly associated abilities also activate partly overlapping regions. Most studies aimed at localizing mathematical function have used group averages, where individual variability is averaged out, thus confounding the anatomical specificity when localizing cognitive functions. Here, we analyze the functional anatomy of the intraparietal cortex by using individual analysis of subregions of IPS based on how they are structurally connected to frontal, parietal, and occipital cortex. Analysis of cortical thickness showed that the right anterior IPS, defined by its connections to the frontal lobe, was associated with both visuospatial working memory, and mathematics in 6-year-old children. This region specialized during development to be specifically related to mathematics, but not visuospatial working memory in adolescents and adults. This could be an example of interactive specialization, where interacting with the environment in combination with interactions between cortical regions leads from a more general role of right anterior IPS in spatial processing, to a specialization of this region for mathematics. Close http://cercor.oxfordjournals.org/cgi/doi/10.1093/cercor/bhw246 doi:10.1093/cercor/bhw246 Close
	Federico Nemmi, Elin Helander, Ola Helenius, Rita Almeida, Martin Hassler, Pekka Räsänen, Torkel Klingberg Behavior and neuroimaging at baseline predict individual response to combined mathematical and working memory training in children Journal Article Developmental Cognitive Neuroscience, 20 , pp. 43–51, 2016, ISSN: 18789293. Abstract \| Links @article{Nemmi2016, title = {Behavior and neuroimaging at baseline predict individual response to combined mathematical and working memory training in children}, author = {Federico Nemmi and Elin Helander and Ola Helenius and Rita Almeida and Martin Hassler and Pekka Räsänen and Torkel Klingberg}, url = {http://dx.doi.org/10.1016/j.dcn.2016.06.004 https://linkinghub.elsevier.com/retrieve/pii/S1878929316300500}, doi = {10.1016/j.dcn.2016.06.004}, issn = {18789293}, year = {2016}, date = {2016-08-01}, journal = {Developmental Cognitive Neuroscience}, volume = {20}, pages = {43--51}, publisher = {Elsevier Ltd}, abstract = {Mathematical performance is highly correlated with several general cognitive abilities, including working memory (WM) capacity. Here we investigated the effect of numerical training using a number-line (NLT), WM training (WMT), or the combination of the two on a composite score of mathematical ability. The aim was to investigate if the combination contributed to the outcome, and determine if baseline performance or neuroimaging predict the magnitude of improvement. We randomly assigned 308, 6-year-old children to WMT, NLT, WMT + NLT or a control intervention. Overall, there was a significant effect of NLT but not WMT. The WMT + NLT was the only group that improved significantly more than the controls, although the interaction NLTxWM was non-significant. Higher WM and maths performance predicted larger benefits for WMT and NLT, respectively. Neuroimaging at baseline also contributed significant information about training gain. Different individuals showed as much as a three-fold difference in their responses to the same intervention. These results show that the impact of an intervention is highly dependent on individual characteristics of the child. If differences in responses could be used to optimize the intervention for each child, future interventions could be substantially more effective.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Mathematical performance is highly correlated with several general cognitive abilities, including working memory (WM) capacity. Here we investigated the effect of numerical training using a number-line (NLT), WM training (WMT), or the combination of the two on a composite score of mathematical ability. The aim was to investigate if the combination contributed to the outcome, and determine if baseline performance or neuroimaging predict the magnitude of improvement. We randomly assigned 308, 6-year-old children to WMT, NLT, WMT + NLT or a control intervention. Overall, there was a significant effect of NLT but not WMT. The WMT + NLT was the only group that improved significantly more than the controls, although the interaction NLTxWM was non-significant. Higher WM and maths performance predicted larger benefits for WMT and NLT, respectively. Neuroimaging at baseline also contributed significant information about training gain. Different individuals showed as much as a three-fold difference in their responses to the same intervention. These results show that the impact of an intervention is highly dependent on individual characteristics of the child. If differences in responses could be used to optimize the intervention for each child, future interventions could be substantially more effective. Close http://dx.doi.org/10.1016/j.dcn.2016.06.004 https://linkinghub.elsevier.com/retr[...] doi:10.1016/j.dcn.2016.06.004 Close
	Christos Constantinidis, Torkel Klingberg The neuroscience of working memory capacity and training Journal Article Nature Reviews Neuroscience, 17 (7), pp. 438–449, 2016, ISSN: 1471-003X. Abstract \| Links @article{Constantinidis2016, title = {The neuroscience of working memory capacity and training}, author = {Christos Constantinidis and Torkel Klingberg}, url = {http://dx.doi.org/10.1038/nrn.2016.43 http://www.nature.com/articles/nrn.2016.43}, doi = {10.1038/nrn.2016.43}, issn = {1471-003X}, year = {2016}, date = {2016-07-01}, journal = {Nature Reviews Neuroscience}, volume = {17}, number = {7}, pages = {438--449}, publisher = {Nature Publishing Group}, abstract = {Working memory (WM) — the ability to maintain and manipulate information over a period of seconds — is a key cognitive skill. Constantinidis and Klingberg discuss non-human-primate, computational-modelling and human-neuroimaging studies that examine the neural bases of WM and training-induced enhancements of WM capacity.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Working memory (WM) — the ability to maintain and manipulate information over a period of seconds — is a key cognitive skill. Constantinidis and Klingberg discuss non-human-primate, computational-modelling and human-neuroimaging studies that examine the neural bases of WM and training-induced enhancements of WM capacity. Close http://dx.doi.org/10.1038/nrn.2016.43 http://www.nature.com/articles/nrn.2016.43 doi:10.1038/nrn.2016.43 Close
	Fahimeh Darki, Federico Nemmi, Annie Möller, Rouslan Sitnikov, Torkel Klingberg Quantitative susceptibility mapping of striatum in children and adults, and its association with working memory performance Journal Article NeuroImage, 136 , pp. 208–214, 2016, ISSN: 10959572. Abstract \| Links @article{Darki2016, title = {Quantitative susceptibility mapping of striatum in children and adults, and its association with working memory performance}, author = {Fahimeh Darki and Federico Nemmi and Annie Möller and Rouslan Sitnikov and Torkel Klingberg}, url = {http://dx.doi.org/10.1016/j.neuroimage.2016.04.065}, doi = {10.1016/j.neuroimage.2016.04.065}, issn = {10959572}, year = {2016}, date = {2016-01-01}, journal = {NeuroImage}, volume = {136}, pages = {208--214}, publisher = {Elsevier Inc.}, abstract = {Quantitative susceptibility mapping (QSM) is a magnetic resonance imaging (MRI) technique in which the magnetic susceptibility characteristic of molecular and cellular components, including iron and myelin, is quantified. Rapid iron accumulation in subcortical nuclei and myelination of the white matter tracts are two important developmental processes that contribute to cognitive functions. Both also contribute to the magnetic susceptibility of the brain tissues. Here, we used the QSM as indirect measures of iron in subcortical nuclei and myelin in caudo-frontal white matter pathways. We included two groups of participants; 21 children aged 6-7 years and 25 adults aged 21-40 years. All subjects also performed tests estimating their visuo-spatial working memory capacity.Adults had higher magnetic susceptibility in all subcortical nuclei, compared to children. The magnetic susceptibility of these nuclei highly correlated with their previously reported iron content. Moreover, working memory performance correlated significantly with the magnetic susceptibility in caudate nucleus in both children and adults, while the correlation was not significant for gray matter density. QSM of white matter in the caudo-frontal tract also differed between children and adults, but did not correlate with working memory scores. These results indicate that QSM is a feasible technique to measure developmental aspects of changes in the striatum, possibly related to iron content that is relevant to cognition.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Quantitative susceptibility mapping (QSM) is a magnetic resonance imaging (MRI) technique in which the magnetic susceptibility characteristic of molecular and cellular components, including iron and myelin, is quantified. Rapid iron accumulation in subcortical nuclei and myelination of the white matter tracts are two important developmental processes that contribute to cognitive functions. Both also contribute to the magnetic susceptibility of the brain tissues. Here, we used the QSM as indirect measures of iron in subcortical nuclei and myelin in caudo-frontal white matter pathways. We included two groups of participants; 21 children aged 6-7 years and 25 adults aged 21-40 years. All subjects also performed tests estimating their visuo-spatial working memory capacity.Adults had higher magnetic susceptibility in all subcortical nuclei, compared to children. The magnetic susceptibility of these nuclei highly correlated with their previously reported iron content. Moreover, working memory performance correlated significantly with the magnetic susceptibility in caudate nucleus in both children and adults, while the correlation was not significant for gray matter density. QSM of white matter in the caudo-frontal tract also differed between children and adults, but did not correlate with working memory scores. These results indicate that QSM is a feasible technique to measure developmental aspects of changes in the striatum, possibly related to iron content that is relevant to cognition. Close http://dx.doi.org/10.1016/j.neuroimage.2016.04.065 doi:10.1016/j.neuroimage.2016.04.065 Close
	Torkel Klingberg Neural basis of cognitive training and development Journal Article Current Opinion in Behavioral Sciences, 10 (i), pp. 97–101, 2016, ISSN: 23521546. Abstract \| Links @article{Klingberg2016, title = {Neural basis of cognitive training and development}, author = {Torkel Klingberg}, url = {http://dx.doi.org/10.1016/j.cobeha.2016.05.003}, doi = {10.1016/j.cobeha.2016.05.003}, issn = {23521546}, year = {2016}, date = {2016-01-01}, journal = {Current Opinion in Behavioral Sciences}, volume = {10}, number = {i}, pages = {97--101}, publisher = {Elsevier Ltd}, abstract = {This paper gives a brief overview of phases in brain development and discusses the hypothesis that mechanisms of working memory development are partly the same as those of working memory training. Brain development could be related to different, but overlapping phases: (i) structural maturation, with a relatively high reliance of preprogrammed processes; (ii) interactive specialization, which is a reorganization of the functional networks, partly in response to the environmental demands; (iii) training or skill learning, which is a qualitative change, such as strengthened connectivity of existent networks. The mechanisms of this skill learning could be similar to those neural processes observed during controlled studies of working memory training, where strengthened connectivity between frontal and parietal regions is suggested to play a central role. Education and formal schooling could be one important factor driving the training and skill-learning phase of executive functions, including improvement of working memory.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close This paper gives a brief overview of phases in brain development and discusses the hypothesis that mechanisms of working memory development are partly the same as those of working memory training. Brain development could be related to different, but overlapping phases: (i) structural maturation, with a relatively high reliance of preprogrammed processes; (ii) interactive specialization, which is a reorganization of the functional networks, partly in response to the environmental demands; (iii) training or skill learning, which is a qualitative change, such as strengthened connectivity of existent networks. The mechanisms of this skill learning could be similar to those neural processes observed during controlled studies of working memory training, where strengthened connectivity between frontal and parietal regions is suggested to play a central role. Education and formal schooling could be one important factor driving the training and skill-learning phase of executive functions, including improvement of working memory. Close http://dx.doi.org/10.1016/j.cobeha.2016.05.003 doi:10.1016/j.cobeha.2016.05.003 Close
2015
	Fahimeh Darki, Torkel Klingberg The role of fronto-parietal and fronto-striatal networks in the development of working memory: A longitudinal study Journal Article Cerebral Cortex, 25 (6), pp. 1587–1595, 2015, ISSN: 14602199. Abstract \| Links @article{Darki2015, title = {The role of fronto-parietal and fronto-striatal networks in the development of working memory: A longitudinal study}, author = {Fahimeh Darki and Torkel Klingberg}, url = {https://academic.oup.com/cercor/article-lookup/doi/10.1093/cercor/bht352}, doi = {10.1093/cercor/bht352}, issn = {14602199}, year = {2015}, date = {2015-06-01}, journal = {Cerebral Cortex}, volume = {25}, number = {6}, pages = {1587--1595}, abstract = {The increase in working memory (WM) capacity is an important part of cognitive development during childhood and adolescence. Cross-sectional analyses have associated this development with higher activity, thinner cortex, and white matter maturation in fronto-parietal networks. However, there is still a lack of longitudinal data showing the dynamics of this development and the role of subcortical structures. We included 89 individuals, aged 6-25 years, who were scanned 1-3 times at 2-year intervals. Functional magnetic resonance imaging (fMRI) was used to identify activated areas in superior frontal, intraparietal cortices, and caudate nucleus during performance on a visuo-spatial WM task. Probabilistic tractography determined the anatomical pathways between these regions. In the cross-sectional analysis, WM capacity correlated with activity in frontal and parietal regions, cortical thickness in parietal cortex, and white matter structure [both fractional anisotropy (FA) and white matter volume] of fronto-parietal and fronto-striatal tracts. However, in the longitudinal analysis, FA in white matter tracts and activity in caudate predicted future WM capacity. The results show a dynamic of neural networks underlying WM development in which cortical activity and structure relate to current capacity, while white matter tracts and caudate activity predict future WM capacity.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close The increase in working memory (WM) capacity is an important part of cognitive development during childhood and adolescence. Cross-sectional analyses have associated this development with higher activity, thinner cortex, and white matter maturation in fronto-parietal networks. However, there is still a lack of longitudinal data showing the dynamics of this development and the role of subcortical structures. We included 89 individuals, aged 6-25 years, who were scanned 1-3 times at 2-year intervals. Functional magnetic resonance imaging (fMRI) was used to identify activated areas in superior frontal, intraparietal cortices, and caudate nucleus during performance on a visuo-spatial WM task. Probabilistic tractography determined the anatomical pathways between these regions. In the cross-sectional analysis, WM capacity correlated with activity in frontal and parietal regions, cortical thickness in parietal cortex, and white matter structure [both fractional anisotropy (FA) and white matter volume] of fronto-parietal and fronto-striatal tracts. However, in the longitudinal analysis, FA in white matter tracts and activity in caudate predicted future WM capacity. The results show a dynamic of neural networks underlying WM development in which cortical activity and structure relate to current capacity, while white matter tracts and caudate activity predict future WM capacity. Close https://academic.oup.com/cercor/article-lookup/doi/10.1093/cercor/bht352 doi:10.1093/cercor/bht352 Close
	Megan Spencer-Smith, Torkel Klingberg Benefits of a working memory training program for inattention in daily life: A systematic review and meta-analysis Journal Article PLoS ONE, 10 (3), pp. 1–18, 2015, ISSN: 19326203. Abstract \| Links @article{Spencer-Smith2015, title = {Benefits of a working memory training program for inattention in daily life: A systematic review and meta-analysis}, author = {Megan Spencer-Smith and Torkel Klingberg}, doi = {10.1371/journal.pone.0119522}, issn = {19326203}, year = {2015}, date = {2015-01-01}, journal = {PLoS ONE}, volume = {10}, number = {3}, pages = {1--18}, abstract = {BACKGROUND: Many common disorders across the lifespan feature impaired working memory (WM). Reported benefits of a WM training program include improving inattention in daily life, but this has not been evaluated in a meta-analysis. This study aimed to evaluate whether one WM training method has benefits for inattention in daily life by conducting a systematic review and meta-analysis. METHODS: We searched Medline and PsycINFO, relevant journals and contacted authors for studies with an intervention and control group reporting post-training estimates of inattention in daily life. To reduce the influence of different WM training methods on the findings, the review was restricted to trials evaluating the Cogmed method. A meta-analysis calculated the pooled standardised difference in means (SMD) between intervention and control groups. RESULTS: A total of 622 studies were identified and 12 studies with 13 group comparisons met inclusion criteria. The meta-analysis showed a significant training effect on inattention in daily life}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close BACKGROUND: Many common disorders across the lifespan feature impaired working memory (WM). Reported benefits of a WM training program include improving inattention in daily life, but this has not been evaluated in a meta-analysis. This study aimed to evaluate whether one WM training method has benefits for inattention in daily life by conducting a systematic review and meta-analysis. METHODS: We searched Medline and PsycINFO, relevant journals and contacted authors for studies with an intervention and control group reporting post-training estimates of inattention in daily life. To reduce the influence of different WM training methods on the findings, the review was restricted to trials evaluating the Cogmed method. A meta-analysis calculated the pooled standardised difference in means (SMD) between intervention and control groups. RESULTS: A total of 622 studies were identified and 12 studies with 13 group comparisons met inclusion criteria. The meta-analysis showed a significant training effect on inattention in daily life Close doi:10.1371/journal.pone.0119522 Close
	Henrik Ullman, Megan Spencer-Smith, Deanne K Thompson, Lex W Doyle, Terrie E Inder, Peter J Anderson, Torkel Klingberg Neonatal MRI is associated with future cognition and academic achievement in preterm children Journal Article Brain, 138 (11), pp. 3251–3262, 2015, ISSN: 14602156. Abstract \| Links @article{Ullman2015, title = {Neonatal MRI is associated with future cognition and academic achievement in preterm children}, author = {Henrik Ullman and Megan Spencer-Smith and Deanne K Thompson and Lex W Doyle and Terrie E Inder and Peter J Anderson and Torkel Klingberg}, doi = {10.1093/brain/awv244}, issn = {14602156}, year = {2015}, date = {2015-01-01}, journal = {Brain}, volume = {138}, number = {11}, pages = {3251--3262}, abstract = {textcopyright 2015 The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com. School-age children born preterm are particularly at risk for low mathematical achievement, associated with reduced working memory and number skills. Early identification of preterm children at risk for future impairments using brain markers might assist in referral for early intervention. This study aimed to examine the use of neonatal magnetic resonance imaging measures derived from automated methods (Jacobian maps from deformation-based morphometry; fractional anisotropy maps from diffusion tensor images) to predict skills important for mathematical achievement (working memory, early mathematical skills) at 5 and 7 years in a cohort of preterm children using both univariable (general linear model) and multivariable models (support vector regression). Participants were preterm children born textless30 weeks' gestational age and healthy control children born ≥37 weeks' gestational age at the Royal Women's Hospital in Melbourne, Australia between July 2001 and December 2003 and recruited into a prospective longitudinal cohort study. At term-equivalent age (±2 weeks) 224 preterm and 46 control infants were recruited for magnetic resonance imaging. Working memory and early mathematics skills were assessed at 5 years (n = 195 preterm; n = 40 controls) and 7 years (n = 197 preterm; n = 43 controls). In the preterm group, results identified localized regions around the insula and putamen in the neonatal Jacobian map that were positively associated with early mathematics at 5 and 7 years (both P textless 0.05), even after covarying for important perinatal clinical factors using general linear model but not support vector regression. The neonatal Jacobian map showed the same trend for association with working memory at 7 years (models ranging from P = 0.07 to P = 0.05). Neonatal fractional anisotropy was positively associated with working memory and early mathematics at 5 years (both P textless 0.001) even after covarying for clinical factors using support vector regression but not general linear model. These significant relationships were not observed in the control group. In summary, we identified, in the preterm brain, regions around the insula and putamen using neonatal deformation-based morphometry, and brain microstructural organization using neonatal diffusion tensor imaging, associated with skills important for childhood mathematical achievement. Results contribute to the growing evidence for the clinical utility of neonatal magnetic resonance imaging for early identification of preterm infants at risk for childhood cognitive and academic impairment.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close textcopyright 2015 The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com. School-age children born preterm are particularly at risk for low mathematical achievement, associated with reduced working memory and number skills. Early identification of preterm children at risk for future impairments using brain markers might assist in referral for early intervention. This study aimed to examine the use of neonatal magnetic resonance imaging measures derived from automated methods (Jacobian maps from deformation-based morphometry; fractional anisotropy maps from diffusion tensor images) to predict skills important for mathematical achievement (working memory, early mathematical skills) at 5 and 7 years in a cohort of preterm children using both univariable (general linear model) and multivariable models (support vector regression). Participants were preterm children born textless30 weeks' gestational age and healthy control children born ≥37 weeks' gestational age at the Royal Women's Hospital in Melbourne, Australia between July 2001 and December 2003 and recruited into a prospective longitudinal cohort study. At term-equivalent age (±2 weeks) 224 preterm and 46 control infants were recruited for magnetic resonance imaging. Working memory and early mathematics skills were assessed at 5 years (n = 195 preterm; n = 40 controls) and 7 years (n = 197 preterm; n = 43 controls). In the preterm group, results identified localized regions around the insula and putamen in the neonatal Jacobian map that were positively associated with early mathematics at 5 and 7 years (both P textless 0.05), even after covarying for important perinatal clinical factors using general linear model but not support vector regression. The neonatal Jacobian map showed the same trend for association with working memory at 7 years (models ranging from P = 0.07 to P = 0.05). Neonatal fractional anisotropy was positively associated with working memory and early mathematics at 5 years (both P textless 0.001) even after covarying for clinical factors using support vector regression but not general linear model. These significant relationships were not observed in the control group. In summary, we identified, in the preterm brain, regions around the insula and putamen using neonatal deformation-based morphometry, and brain microstructural organization using neonatal diffusion tensor imaging, associated with skills important for childhood mathematical achievement. Results contribute to the growing evidence for the clinical utility of neonatal magnetic resonance imaging for early identification of preterm infants at risk for childhood cognitive and academic impairment. Close doi:10.1093/brain/awv244 Close
2014
	Sissela Bergman-Nutley, Torkel Klingberg Effect of working memory training on working memory, arithmetic and following instructions Journal Article Psychological Research, 78 (6), pp. 869–877, 2014, ISSN: 0340-0727. Abstract \| Links @article{Bergman-Nutley2014, title = {Effect of working memory training on working memory, arithmetic and following instructions}, author = {Sissela Bergman-Nutley and Torkel Klingberg}, url = {http://link.springer.com/10.1007/s00426-014-0614-0}, doi = {10.1007/s00426-014-0614-0}, issn = {0340-0727}, year = {2014}, date = {2014-11-01}, journal = {Psychological Research}, volume = {78}, number = {6}, pages = {869--877}, abstract = {Abstract Mathematical ability is dependent on specific mathematical training but also associated with a range of cognitive factors, including working memory (WM) capacity. Previous studies have shown that WM training leads to improvement in non-trained WM tasks, but the results regarding transfer to mathematics are inconclusive. In the present study, 176 children with WM deficits, aged 7–15 years performed 5 weeks ofWMtraining. During the training period, they were assessed five times with a test of complex WM (the Odd One Out), a test of remembering and following instructions and a test of arithmetic. The improvements were compared to the performance of a control group of 304 typically developing children aged 7–15 years who performed the same transfer tasks at the same time intervals, but without training. The training group improved significantly more than the control group on all three transfer tests (all p$backslash$0.0001), after correction for baseline performance, age and sex. The effect size for mathematics was small and the effect sizes for the WM tasks were moderate to large. The transfer increased line- arly with the amount of training time and correlated with the amount of improvement on the trained tasks. These results confirm previous findings of training-induced improvements in non-trained WM tasks including the ability to follow instructions, but extend previous findings by showing improvements also for arithmetic. This is encouraging regarding the potential role of cognitive training for education, but it is desirable to find paradigms that would enhance the effect of the training on mathe- matics. One of the future challenges for studying training effects is combining large sample sizes with high quality and compliance, to detect relevant but smaller effects of cognitive training.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Abstract Mathematical ability is dependent on specific mathematical training but also associated with a range of cognitive factors, including working memory (WM) capacity. Previous studies have shown that WM training leads to improvement in non-trained WM tasks, but the results regarding transfer to mathematics are inconclusive. In the present study, 176 children with WM deficits, aged 7–15 years performed 5 weeks ofWMtraining. During the training period, they were assessed five times with a test of complex WM (the Odd One Out), a test of remembering and following instructions and a test of arithmetic. The improvements were compared to the performance of a control group of 304 typically developing children aged 7–15 years who performed the same transfer tasks at the same time intervals, but without training. The training group improved significantly more than the control group on all three transfer tests (all p$backslash$0.0001), after correction for baseline performance, age and sex. The effect size for mathematics was small and the effect sizes for the WM tasks were moderate to large. The transfer increased line- arly with the amount of training time and correlated with the amount of improvement on the trained tasks. These results confirm previous findings of training-induced improvements in non-trained WM tasks including the ability to follow instructions, but extend previous findings by showing improvements also for arithmetic. This is encouraging regarding the potential role of cognitive training for education, but it is desirable to find paradigms that would enhance the effect of the training on mathe- matics. One of the future challenges for studying training effects is combining large sample sizes with high quality and compliance, to detect relevant but smaller effects of cognitive training. Close http://link.springer.com/10.1007/s00426-014-0614-0 doi:10.1007/s00426-014-0614-0 Close
	Torkel Klingberg Childhood cognitive development as a skill Journal Article Trends in Cognitive Sciences, 18 (11), pp. 573–579, 2014, ISSN: 13646613. Abstract \| Links @article{Klingberg2014, title = {Childhood cognitive development as a skill}, author = {Torkel Klingberg}, url = {http://dx.doi.org/10.1016/j.tics.2014.06.007 https://www.sciencedirect.com/science/article/pii/S1364661314001533 http://linkinghub.elsevier.com/retrieve/pii/S1364661314001533 https://linkinghub.elsevier.com/retrieve/pii/S1364661314001533}, doi = {10.1016/j.tics.2014.06.007}, issn = {13646613}, year = {2014}, date = {2014-11-01}, journal = {Trends in Cognitive Sciences}, volume = {18}, number = {11}, pages = {573--579}, publisher = {Elsevier Current Trends}, abstract = {Theories view childhood development as being either driven by structural maturation of the brain or being driven by skill-learning. It is hypothesized here that working memory (WM) development during childhood is partly driven by training effects in the environment, and that similar neural mechanisms underlie training-induced plasticity and childhood development. In particular, the functional connectivity of a fronto-parietal network is suggested to be associated with WM capacity. The striatum, dopamine receptor D2 (DRD2) activity, and corticostriatal white-matter tracts, on the other hand, seem to be more important for plasticity and change of WM capacity during both training and development. In this view, the development of WM capacity during childhood partly involves the same mechanisms as skill-learning.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Theories view childhood development as being either driven by structural maturation of the brain or being driven by skill-learning. It is hypothesized here that working memory (WM) development during childhood is partly driven by training effects in the environment, and that similar neural mechanisms underlie training-induced plasticity and childhood development. In particular, the functional connectivity of a fronto-parietal network is suggested to be associated with WM capacity. The striatum, dopamine receptor D2 (DRD2) activity, and corticostriatal white-matter tracts, on the other hand, seem to be more important for plasticity and change of WM capacity during both training and development. In this view, the development of WM capacity during childhood partly involves the same mechanisms as skill-learning. Close http://dx.doi.org/10.1016/j.tics.2014.06.007 https://www.sciencedirect.com/scien[...] doi:10.1016/j.tics.2014.06.007 Close
	Charlotte Nymberg, Tobias Banaschewski, Arun LW Bokde, Christian Büchel, Patricia Conrod, Herta Flor, Vincent Frouin, Hugh Garavan, P Gowland, Andreas Heinz, Bernd Ittermann, Karl Mann, Jean-Luc Martinot, Frauke Nees, Tomas Paus, Zdenka Pausova, Marcella Rietschel, Trevor W Robbins, Michael N Smolka, Andreas Ströhle, Gunter Schumann, Torkel Klingberg DRD2/ANKK1 Polymorphism Modulates the Effect of Ventral Striatal Activation on Working Memory Performance Journal Article Neuropsychopharmacology, 39 (10), pp. 2357–2365, 2014, ISSN: 0893-133X. Abstract \| Links @article{Nymberg2014, title = {DRD2/ANKK1 Polymorphism Modulates the Effect of Ventral Striatal Activation on Working Memory Performance}, author = {Charlotte Nymberg and Tobias Banaschewski and Arun LW Bokde and Christian Büchel and Patricia Conrod and Herta Flor and Vincent Frouin and Hugh Garavan and P Gowland and Andreas Heinz and Bernd Ittermann and Karl Mann and Jean-Luc Martinot and Frauke Nees and Tomas Paus and Zdenka Pausova and Marcella Rietschel and Trevor W Robbins and Michael N Smolka and Andreas Ströhle and Gunter Schumann and Torkel Klingberg}, url = {http://www.nature.com/articles/npp201483}, doi = {10.1038/npp.2014.83}, issn = {0893-133X}, year = {2014}, date = {2014-09-01}, journal = {Neuropsychopharmacology}, volume = {39}, number = {10}, pages = {2357--2365}, abstract = {Motivation is important for learning and cognition. Although dopaminergic (D2) transmission in the ventral striatum (VS) is associated with motivation, learning, and cognition are more strongly associated with function of the dorsal striatum, including activation in the caudate nucleus. A recent study found an interaction between intrinsic motivation and the DRD2/ANKK1 polymorphism (rs1800497), suggesting that A-carriers of rs1800497 are significantly more sensitive to motivation in order to improve during working memory (WM) training. Using data from the two large-scale imaging genetic data sets, IMAGEN (n=1080, age 13-15 years) and BrainChild (n∼300, age 6-27), we investigated whether rs1800497 is associated with WM. In the IMAGEN data set, we tested whether VS/caudate activation during reward anticipation was associated with WM performance and whether rs1800497 and VS/caudate activation interact to affect WM performance. We found that rs1800497 was associated with WM performance in IMAGEN and BrainChild. Higher VS and caudate activation during reward processing were significantly associated with higher WM performance (ptextless0.0001). An interaction was found between the DRD2/ANKK1 polymorphism rs1800497 and VS activation during reward anticipation on WM (ptextless0.01), such that carriers of the minor allele (A) showed a significant correlation between VS activation and WM, whereas the GG-homozygotes did not, suggesting that the effect of VS BOLD on WM is modified by inter-individual genetic differences related to D2 dopaminergic transmission. textcopyright 2014 American College of Neuropsychopharmacology.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Motivation is important for learning and cognition. Although dopaminergic (D2) transmission in the ventral striatum (VS) is associated with motivation, learning, and cognition are more strongly associated with function of the dorsal striatum, including activation in the caudate nucleus. A recent study found an interaction between intrinsic motivation and the DRD2/ANKK1 polymorphism (rs1800497), suggesting that A-carriers of rs1800497 are significantly more sensitive to motivation in order to improve during working memory (WM) training. Using data from the two large-scale imaging genetic data sets, IMAGEN (n=1080, age 13-15 years) and BrainChild (n∼300, age 6-27), we investigated whether rs1800497 is associated with WM. In the IMAGEN data set, we tested whether VS/caudate activation during reward anticipation was associated with WM performance and whether rs1800497 and VS/caudate activation interact to affect WM performance. We found that rs1800497 was associated with WM performance in IMAGEN and BrainChild. Higher VS and caudate activation during reward processing were significantly associated with higher WM performance (ptextless0.0001). An interaction was found between the DRD2/ANKK1 polymorphism rs1800497 and VS activation during reward anticipation on WM (ptextless0.01), such that carriers of the minor allele (A) showed a significant correlation between VS activation and WM, whereas the GG-homozygotes did not, suggesting that the effect of VS BOLD on WM is modified by inter-individual genetic differences related to D2 dopaminergic transmission. textcopyright 2014 American College of Neuropsychopharmacology. Close http://www.nature.com/articles/npp201483 doi:10.1038/npp.2014.83 Close
	H Ullman, R Almeida, Torkel Klingberg Structural Maturation and Brain Activity Predict Future Working Memory Capacity during Childhood Development Journal Article Journal of Neuroscience, 34 (5), pp. 1592–1598, 2014, ISSN: 0270-6474. Abstract \| Links @article{Ullman2014, title = {Structural Maturation and Brain Activity Predict Future Working Memory Capacity during Childhood Development}, author = {H Ullman and R Almeida and Torkel Klingberg}, url = {http://www.jneurosci.org/cgi/doi/10.1523/JNEUROSCI.0842-13.2014}, doi = {10.1523/JNEUROSCI.0842-13.2014}, issn = {0270-6474}, year = {2014}, date = {2014-01-01}, journal = {Journal of Neuroscience}, volume = {34}, number = {5}, pages = {1592--1598}, abstract = {Human working memory capacity develops during childhood and is a strong predictor of future academic performance, in particular, achievements in mathematics and reading. Predicting working memory development is important for the early identification of children at risk for poor cognitive and academic development. Here we show that structural and functional magnetic resonance imaging data explain variance in children's working memory capacity 2 years later, which was unique variance in addition to that predicted using cognitive tests. While current working memory capacity correlated with frontoparietal cortical activity, the future capacity could be inferred from structure and activity in basal ganglia and thalamus. This gives a novel insight into the neural mechanisms of childhood development and supports the idea that neuroimaging can have a unique role in predicting children's cognitive development.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Human working memory capacity develops during childhood and is a strong predictor of future academic performance, in particular, achievements in mathematics and reading. Predicting working memory development is important for the early identification of children at risk for poor cognitive and academic development. Here we show that structural and functional magnetic resonance imaging data explain variance in children's working memory capacity 2 years later, which was unique variance in addition to that predicted using cognitive tests. While current working memory capacity correlated with frontoparietal cortical activity, the future capacity could be inferred from structure and activity in basal ganglia and thalamus. This gives a novel insight into the neural mechanisms of childhood development and supports the idea that neuroimaging can have a unique role in predicting children's cognitive development. Close http://www.jneurosci.org/cgi/doi/10.1523/JNEUROSCI.0842-13.2014 doi:10.1523/JNEUROSCI.0842-13.2014 Close
	F Darki, M Peyrard-Janvid, H Matsson, J Kere, T Klingberg DCDC2 Polymorphism Is Associated with Left Temporoparietal Gray and White Matter Structures during Development Journal Article Journal of Neuroscience, 34 (43), pp. 14455–14462, 2014, ISSN: 0270-6474. Abstract \| Links @article{Darki2014, title = {DCDC2 Polymorphism Is Associated with Left Temporoparietal Gray and White Matter Structures during Development}, author = {F Darki and M Peyrard-Janvid and H Matsson and J Kere and T Klingberg}, doi = {10.1523/jneurosci.1216-14.2014}, issn = {0270-6474}, year = {2014}, date = {2014-01-01}, journal = {Journal of Neuroscience}, volume = {34}, number = {43}, pages = {14455--14462}, abstract = {textcopyright 2014 the authors. Three genes, DYX1C1, DCDC2, and KIAA0319, have been previously associated with dyslexia, neuronal migration, and ciliary function. Three polymorphisms within these genes, rs3743204 (DYX1C1), rs793842 (DCDC2), and rs6935076 (KIAA0319) have also been linked to normal variability of left temporoparietal white matter volume connecting the middle temporal cortex to the angular and supramarginal gyri. Here, we assessed whether these polymorphisms are also related to the cortical thickness of the associated regions during childhood development using a longitudinal dataset of 76 randomly selected children and young adults who were scanned up to three times each, 2 years apart. rs793842 in DCDC2 was significantly associated with the thickness of left angular and supramarginal gyri as well as the left lateral occipital cortex. The cortex was significantly thicker for T-allele carriers, who also had lower white matter volume and lower reading comprehension scores. There was a negative correlation between white matter volume and cortical thickness, but only white matter volume predicted reading comprehension 2 years after scanning. These results show how normal variability in reading comprehension is related to gene, white matter volume, and cortical thickness in the inferior parietal lobe. Possibly, the variability of gray and white matter structures could both be related to the role of DCDC2 in ciliary function, which affects both neuronal migration and axonal outgrowth.}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close textcopyright 2014 the authors. Three genes, DYX1C1, DCDC2, and KIAA0319, have been previously associated with dyslexia, neuronal migration, and ciliary function. Three polymorphisms within these genes, rs3743204 (DYX1C1), rs793842 (DCDC2), and rs6935076 (KIAA0319) have also been linked to normal variability of left temporoparietal white matter volume connecting the middle temporal cortex to the angular and supramarginal gyri. Here, we assessed whether these polymorphisms are also related to the cortical thickness of the associated regions during childhood development using a longitudinal dataset of 76 randomly selected children and young adults who were scanned up to three times each, 2 years apart. rs793842 in DCDC2 was significantly associated with the thickness of left angular and supramarginal gyri as well as the left lateral occipital cortex. The cortex was significantly thicker for T-allele carriers, who also had lower white matter volume and lower reading comprehension scores. There was a negative correlation between white matter volume and cortical thickness, but only white matter volume predicted reading comprehension 2 years after scanning. These results show how normal variability in reading comprehension is related to gene, white matter volume, and cortical thickness in the inferior parietal lobe. Possibly, the variability of gray and white matter structures could both be related to the role of DCDC2 in ciliary function, which affects both neuronal migration and axonal outgrowth. Close doi:10.1523/jneurosci.1216-14.2014 Close
	Sissela Bergman Nutley, Fahimeh Darki, Torkel Klingberg Music practice is associated with development of working memory during childhood and adolescence Journal Article Frontiers in Human Neuroscience, 7 (January), pp. 1–9, 2014. Abstract \| Links @article{BergmanNutley2014, title = {Music practice is associated with development of working memory during childhood and adolescence}, author = {Sissela {Bergman Nutley} and Fahimeh Darki and Torkel Klingberg}, doi = {10.3389/fnhum.2013.00926}, year = {2014}, date = {2014-01-01}, journal = {Frontiers in Human Neuroscience}, volume = {7}, number = {January}, pages = {1--9}, abstract = {Practicing a musical instrument is associated with cognitive benefits and structural brain changes in correlational and interventional trials; however, the effect of musical training on cognition during childhood is still unclear. In this longitudinal study of child development we analyzed the association between musical practice and performance on reasoning, processing speed and working memory (WM) during development. Subjects (n = 352) between the ages of 6 and 25 years participated in neuropsychological assessments and neuroimaging investigations (n = 64) on two or three occasions, 2 years apart. Mixed model regression showed that musical practice had an overall positive association with WM capacity (visuo-spatial WM}, keywords = {}, pubstate = {published}, tppubtype = {article} } Close Practicing a musical instrument is associated with cognitive benefits and structural brain changes in correlational and interventional trials; however, the effect of musical training on cognition during childhood is still unclear. In this longitudinal study of child development we analyzed the association between musical practice and performance on reasoning, processing speed and working memory (WM) during development. Subjects (n = 352) between the ages of 6 and 25 years participated in neuropsychological assessments and neuroimaging investigations (n = 64) on two or three occasions, 2 years apart. Mixed model regression showed that musical practice had an overall positive association with WM capacity (visuo-spatial WM Close doi:10.3389/fnhum.2013.00926 Close

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