Abstract
The canonical approach to exploring brain-behaviour relationships is to group individuals according to a phenotype of interest, and then explore the neural correlates of this grouping. A limitation of this approach is that multiple aetiological pathways could result in a similar phenotype, so the role of any one brain mechanism may be substantially underestimated. Building on advances in network analysis, we used a data-driven community-clustering algorithm to identify robust subgroups based on white-matter microstructure in childhood and adolescence (total N = 313, mean age: 11.24 years). The algorithm indicated the presence of two equal-size groups that show a critical difference in fractional anisotropy (FA) of the left and right cingulum. Applying the brain-based grouping in independent samples, we find that these different ‘brain types’ had profoundly different cognitive abilities with higher performance in the higher FA group. Further, a connectomics analysis indicated reduced structural connectivity in the low FA subgroup that was strongly related to reduced functional activation of the default mode network. These results provide a proof-of-concept that bottom-up brain-based groupings can be identified that relate to cognitive performance. This provides a first demonstration of a complimentary approach for investigating individual differences in brain structure and function, particularly for neurodevelopmental disorders where researchers are often faced with phenotypes that are difficult to define at the cognitive or behavioural level.
Highlights
Differential psychology is an influential strand of modern psychology, concerned with identifying dimensions upon which individuals differ
Dyslexia is associated with a reduced organisation in white matter pathways along the left dorsal and ventral language pathways[17]; children with Attention Deficit Hyperactivity Disorder (ADHD) show reduced white matter organisation of the corpus callosum and major tracts of the right hemisphere[18], and reduced integrity of connections between the limbic system and frontal and temporal cortex has been reported for autism spectrum disorder (ASD)[19]
Grouping children in the NKI sample according to their similarity of fractional anisotropy (FA) values within major white matter tracts using consensus clustering indicated the presence of two groups
Summary
Differential psychology is an influential strand of modern psychology, concerned with identifying dimensions upon which individuals differ This approach has been applied at different points across development, from childhood to old adulthood, and has been central to our understanding of typical and atypical behaviour and psychopathology[1,2]. Network science tools for community detection have been successfully used to identify social groups in phone networks and to identify brain regions with similar function[22] This approach has been successfully applied to distinguish differences in behaviour within heterogeneous groups, such as subgroups of neuropsychological function in typically-developing children[8] and subgroups of executive function-related behavioural problems in children who struggle in school[9]. Community detection was applied to detect subgroups of participants with similar microstructure in 20 major tracts
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
