title: Brain structures associated with executive functions during everyday events in a non-clinical sample.
abstract: Executive functions involve control processes such as goal-oriented planning, flexible strategy generation, sustaining set maintenance, self-monitoring, and inhibition. Executive functions during everyday events (EFEEs) are distinct from those measured under laboratory settings; the former can be severely impaired while the latter remain intact. Non-routine everyday problems due to executive dysfunctions affect individual functioning in everyday life and are of great clinical interest. Despite the importance of anatomical bases underlying better EFEEs, such bases have never been investigated among non-clinical samples. Using voxel-based morphometry to measure regional gray matter volume (rGMV) and regional white matter volume (rWMV) and diffusion tensor imaging to determine fractional anisotropy values, we identified the anatomical correlates of better EFEEs using the Dysexecutive Questionnaire in 303 normal young subjects (168 men and 135 women). Better EFEEs were associated with a smaller rGMV in the orbitofrontal cortex (OFC) spread across Brodmann areas (BA) 25, 11, and 12 and larger rWMV in the WM area of OFC adjacent to BA 11. Furthermore, individual EFEEs were positively associated with rWMV in the temporal areas, primarily the inferior longitudinal fasciculus and inferior fronto-occipital fasciculus, the latter of which connects OFC and posterior regions. Thus, our findings suggest that brain structures involving OFC, together with other regions, contribute to the maintenance of effective EFEEs among non-clinical subjects.
authors.affiliation: Smart Ageing International Research Center, Institute of Development, Aging and Cancer, Tohoku University, 4-1 Seiryo-cho, Aoba-ku, Sendai 980-8575, Japan. takehi@idac.tohoku.ac.jp
authors.forename: Hikaru
authors.initials: H
authors.lastname: Takeuchi
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Taki
authors.forename: Yuko
authors.initials: Y
authors.lastname: Sassa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Hashizume
authors.forename: Atsushi
authors.initials: A
authors.lastname: Sekiguchi
authors.forename: Ai
authors.initials: A
authors.lastname: Fukushima
authors.forename: Ryuta
authors.initials: R
authors.lastname: Kawashima
mesh_terms: D000704:Analysis of Variance; D016880:Anisotropy; D001837:Body Weights and Measures; D001921:Brain / Q000033:anatomy & histology* / Q000502:physiology*; D056324:Diffusion Tensor Imaging; D056344:Executive Function / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009413:Nerve Fibers, Myelinated / Q000502:physiology; D036421:Nerve Fibers, Unmyelinated / Q000502:physiology; D011795:Surveys and Questionnaires; D055815:Young Adult