title: Anatomical Abnormalities in Autism?
abstract: Substantial controversy exists regarding the presence and significance of anatomical abnormalities in autism spectrum disorders (ASD). The release of the Autism Brain Imaging Data Exchange (∼1000 participants, age 6-65 years) offers an unprecedented opportunity to conduct large-scale comparisons of anatomical MRI scans across groups and to resolve many of the outstanding questions. Comprehensive univariate analyses using volumetric, thickness, and surface area measures of over 180 anatomically defined brain areas, revealed significantly larger ventricular volumes, smaller corpus callosum volume (central segment only), and several cortical areas with increased thickness in the ASD group. Previously reported anatomical abnormalities in ASD including larger intracranial volumes, smaller cerebellar volumes, and larger amygdala volumes were not substantiated by the current study. In addition, multivariate classification analyses yielded modest decoding accuracies of individuals' group identity (<60%), suggesting that the examined anatomical measures are of limited diagnostic utility for ASD. While anatomical abnormalities may be present in distinct subgroups of ASD individuals, the current findings show that many previously reported anatomical measures are likely to be of low clinical and scientific significance for understanding ASD neuropathology as a whole in individuals 6-35 years old.
authors.affiliation: Department of Brain and Cognitive Sciences, Ben Gurion University of the Negev, Beer Sheva 84105, Israel.
authors.forename: Shlomi
authors.initials: S
authors.lastname: Haar
authors.affiliation: Department of Industrial Engineering and Management, Ben Gurion University of the Negev, Beer Sheva 84105, Israel.
authors.forename: Sigal
authors.initials: S
authors.lastname: Berman
authors.affiliation: Department of Psychology, Carnegie Mellon University, Pittsburgh, PA 15213, USA.
authors.forename: Marlene
authors.initials: M
authors.lastname: Behrmann
authors.affiliation: Department of Brain and Cognitive Sciences, Ben Gurion University of the Negev, Beer Sheva 84105, Israel Department of Psychology, Ben Gurion University of the Negev, Beer Sheva 84105, Israel.
authors.forename: Ilan
authors.initials: I
authors.lastname: Dinstein
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000067877:Autism Spectrum Disorder; D001321:Autistic Disorder / Q000473:pathology*; D001921:Brain / Q000002:abnormalities*; D002648:Child; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D055815:Young Adult
keywords: MRI; anatomy; autism; thickness; volume