title: Smaller insula and inferior frontal volumes in young adults with pervasive developmental disorders.
abstract: Enlarged head circumference and increased brain weight have been reported in infants with pervasive developmental disorders (PDD), and volumetric studies suggest that children with PDD have abnormally enlarged brain volumes. However, little is known about brain volume abnormalities in young adults with PDD. We explored gray matter (GM) volume in young adults with PDD. T1-weighted volumetric images were acquired with a 3-T magnetic resonance scanner from 32 males with high-functioning PDD (23.8+/-4.2 years; Full Scale Intelligence Quotient [FSIQ]=101.6+/-15.6) and 40 age-matched normal male control subjects (22.5+/-4.3 years; FSIQ=109.7+/-7.9). Regional GM volumes were compared between the two groups using voxel-based morphometry (VBM) with the Diffeomorphic Anatomical Registration using Exponentiated Lie algebra (DARTEL). Compared with the control group, the high-functioning PDD group showed significantly less GM in the right insula, the right inferior frontal gyrus, and the right inferior parietal lobule. A conservative threshold confirmed considerably smaller volumes in the right insula and inferior frontal gyrus. In these areas, negative correlations were found between Autism Spectrum Quotient scores and GM volume, although no significant correlations were found between each subject's FSIQ and GM volume. No regions showed greater GM volumes in the high-functioning PDD group. The insular cortex, which works as a relay area for multiple neurocognitive systems, may be one of the key regions underlying the complex clinical features of PDD. These smaller GM volumes in high-functioning PDD subjects may reflect the clinical features of PDD itself, rather than FSIQ.
authors.affiliation: Department of Neuropsychiatry, Faculty of Medical Sciences, University of Fukui, Eiheiji, Fukui, 910-1193, Japan. hirotaka@u-fukui.ac.jp
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Kosaka
authors.forename: Masao
authors.initials: M
authors.lastname: Omori
authors.forename: Toshio
authors.initials: T
authors.lastname: Munesue
authors.forename: Makoto
authors.initials: M
authors.lastname: Ishitobi
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Matsumura
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Takahashi
authors.forename: Kousuke
authors.initials: K
authors.lastname: Narita
authors.forename: Tetsuhito
authors.initials: T
authors.lastname: Murata
authors.forename: Daisuke N
authors.initials: DN
authors.lastname: Saito
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Uchiyama
authors.forename: Tomoyo
authors.initials: T
authors.lastname: Morita
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Kikuchi
authors.forename: Kimiko
authors.initials: K
authors.lastname: Mizukami
authors.forename: Hidehiko
authors.initials: H
authors.lastname: Okazawa
authors.forename: Norihiro
authors.initials: N
authors.lastname: Sadato
authors.forename: Yuji
authors.initials: Y
authors.lastname: Wada
mesh_terms: D000293:Adolescent; D000328:Adult; D020817:Asperger Syndrome / Q000473:pathology*; D001321:Autistic Disorder / Q000473:pathology*; D002658:Developmental Disabilities / Q000473:pathology; D005625:Frontal Lobe / Q000473:pathology*; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007361:Intelligence Tests; D008279:Magnetic Resonance Imaging; D008297:Male; D036421:Nerve Fibers, Unmyelinated / Q000473:pathology; D009929:Organ Size; D012720:Severity of Illness Index; D013702:Temporal Lobe / Q000473:pathology*; D055815:Young Adult