title: The local, global, and neural aspects of visuospatial processing in autism spectrum disorders.
abstract: Behavioral studies have documented a relative advantage in some aspects of visuospatial cognition in autism although it is not consistently found in higher functioning individuals with autism. The purpose of this functional neuroimaging study was to examine the neural activity in high functioning individuals with autism while they performed a block design task that systematically varied with regard to whether a global pattern was present. Participants were 14 adults with high-functioning autism and 14 age and IQ matched typical controls. The task was to identify a missing block in target figures which had either an obvious global shape or was an arbitrary array of blocks. Behavioral results showed intact, but not superior, performance in our participants with autism. A key group difference was that the participants with autism showed reliably greater activation in occipital and parietal regions in both tasks suggesting an increased reliance of the autism group on posterior brain areas to mediate visuospatial tasks. Thus, increased reliance on relatively posterior brain regions in itself may not guarantee superior performance as seen in the present study.
authors.affiliation: Department of Psychology, University of Alabama at Birmingham, Civitan International Research Center CIRC 235G, 1719 6th Ave South, Birmingham, AL, United States. Electronic address: rkana@uab.edu.
authors.forename: Rajesh K
authors.initials: RK
authors.lastname: Kana
authors.forename: Yanni
authors.initials: Y
authors.lastname: Liu
authors.forename: Diane L
authors.initials: DL
authors.lastname: Williams
authors.forename: Timothy A
authors.initials: TA
authors.lastname: Keller
authors.forename: Sarah E
authors.initials: SE
authors.lastname: Schipul
authors.forename: Nancy J
authors.initials: NJ
authors.lastname: Minshew
authors.forename: Marcel Adam
authors.initials: MA
authors.lastname: Just
mesh_terms: D000704:Analysis of Variance; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000098:blood supply / Q000503:physiopathology*; D002659:Child Development Disorders, Pervasive / Q000150:complications*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D009483:Neuropsychological Tests; D010100:Oxygen / Q000097:blood; D010364:Pattern Recognition, Visual; D010468:Perceptual Disorders / Q000209:etiology* / Q000473:pathology; D010775:Photic Stimulation; D013028:Space Perception / Q000502:physiology*
chemical_list: D010100:Oxygen
keywords: Autism; Block design task; Global–local processing; fMRI