title: Increased left hemisphere impairment in high-functioning autism: a tract based spatial statistics study.
abstract: There is evidence emerging from Diffusion Tensor Imaging (DTI) research that autism spectrum disorders (ASD) are associated with greater impairment in the left hemisphere. Although this has been quantified with volumetric region of interest analyses, it has yet to be tested with white matter integrity analysis. In the present study, tract based spatial statistics was used to contrast white matter integrity of 12 participants with high-functioning autism or Aspergers syndrome (HFA/AS) with 12 typically developing individuals. Fractional Anisotropy (FA) was examined, in addition to axial, radial and mean diffusivity (AD, RD and MD). In the left hemisphere, participants with HFA/AS demonstrated significantly reduced FA in predominantly thalamic and fronto-parietal pathways and increased RD. Symmetry analyses confirmed that in the HFA/AS group, WM disturbance was significantly greater in the left compared to right hemisphere. These findings contribute to a growing body of literature suggestive of reduced FA in ASD, and provide preliminary evidence for RD impairments in the left hemisphere.
authors.affiliation: Cognitive Neuroscience Unit, Department of Psychology, School of Psychology, Faculty of Health, Deakin University, 221 Burwood Highway, Victoria, Australia. Electronic address: tperkin@deakin.edu.au.
authors.forename: Thomas John
authors.initials: TJ
authors.lastname: Perkins
authors.affiliation: Cognitive Neuroscience Unit, Department of Psychology, School of Psychology, Faculty of Health, Deakin University, 221 Burwood Highway, Victoria, Australia.
authors.forename: Mark Andrew
authors.initials: MA
authors.lastname: Stokes
authors.affiliation: Cognitive Neuroscience Unit, Department of Psychology, School of Psychology, Faculty of Health, Deakin University, 221 Burwood Highway, Victoria, Australia.
authors.forename: Jane Anne
authors.initials: JA
authors.lastname: McGillivray
authors.affiliation: Cognitive Neuroscience Unit, Department of Psychology, School of Psychology, Faculty of Health, Deakin University, 221 Burwood Highway, Victoria, Australia.
authors.forename: Alexander Julien
authors.initials: AJ
authors.lastname: Mussap
authors.affiliation: Cognitive Neuroscience Unit, Department of Psychology, School of Psychology, Faculty of Health, Deakin University, 221 Burwood Highway, Victoria, Australia.
authors.forename: Ivanna Anne
authors.initials: IA
authors.lastname: Cox
authors.affiliation: Monash Alfred Psychiatry Research Centre, The Alfred and Monash University Central Clinical School, Commercial Rd, Melbourne, Victoria, Australia.
authors.forename: Jerome Joseph
authors.initials: JJ
authors.lastname: Maller
authors.affiliation: Cognitive Neuroscience Unit, Department of Psychology, School of Psychology, Faculty of Health, Deakin University, 221 Burwood Highway, Victoria, Australia; Precision Brain Spine and Pain Centre, Australia; Department of Neurosurgery, Royal Melbourne Hospital, Australia.
authors.forename: Richard Garth
authors.initials: RG
authors.lastname: Bittar
mesh_terms: D000328:Adult; D016880:Anisotropy; D001921:Brain / Q000473:pathology; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000473:pathology*; D002659:Child Development Disorders, Pervasive / Q000473:pathology*; D056324:Diffusion Tensor Imaging; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008297:Male; D055815:Young Adult
keywords: Autism spectrum disorder; Diffusion Tensor Imaging; Fractional Anisotropy; Radial Diffusivity