Structural brain basis of latent factors of executive functions in childhood.

Executive functions can be classified into processes of inhibition, working memory and shifting, which together support flexible and goal-directed behaviour and are crucial for both current and later-life outcomes. A large body of literature has identified distinct brain regions critical to performing each of these functions. These findings are however predicated on a piecemeal and single-task approach. It is therefore unclear to what extent these associations reflect task-specific features or actual constructs of executive functions. Here, in a sample of 141 children aged 6-13 years, we administered a battery of 9 executive function tasks, derived latent factors of inhibition, working memory, and shifting and examined their associations with markers of brain structure (whole-brain cortical thickness). We identified associations between working memory and cortical thickness of right superior frontal and left medial temporal lobe as well as associations between shifting and cortical thickness in bilateral frontal and occipital lobes and left medial and anterior temporal lobes. While working memory and shifting shared a cortical substrate in right superior frontal cortex as well as left middle and inferior temporal regions no significant brain clusters were associated with inhibition. We discuss these findings in relation to theories of executive functions and their development.