title: Smaller corpus callosum subregions containing motor fibers in schizophrenia.
abstract: Neuropsychological and neurophysiological studies provide evidence for abnormal interhemispheric communication in schizophrenia. These abnormalities may have a substrate in structural irregularities of the corpus callosum. This study investigated schizophrenia patients (n=27) and healthy comparison subjects (n=31). Global and regional measurements of the corpus callosum were acquired from one midsagittal SPGR slice. Eight subregions were approximately matched to fiber pathways from cortical regions. Overall effects of diagnosis [Wilks' Lambda F(8,46)=2.45, p=0.03] and diagnosis by age interaction [Wilks' Lambda F(8,46)=2.58, p=0.02] were found in a MANCOVA of the eight functionally specific subregions. Specifically, chronic schizophrenia was associated with a smaller rostral body [lower by 6.9%, F(1,53)=9.70, p=0.003] and anterior midbody [lower by 9.7%, F(1,53)=4.89, p=0.03] subregions. The rostral body and anterior midbody subregions of the corpus callosum primarily have premotor, supplementary motor, and motor cortical fibers transversing through them. Functional abnormalities of the associated cortical regions are reported in schizophrenia. These novel findings suggest that structural abnormalities of the corpus callosum exist in schizophrenia, with perhaps the motor-specific subregions affected more than others. Structural differences in the corpus callosum may be a substrate for interhemispheric functional dysconnectivity in schizophrenia.
authors.affiliation: Centre for Complex Disorders, Department of Psychiatry, University of British Columbia, Vancouver, BC, Canada. gogh0001@umn.edu
authors.forename: Vina M
authors.initials: VM
authors.lastname: Goghari
authors.forename: Donna J
authors.initials: DJ
authors.lastname: Lang
authors.forename: Sean W
authors.initials: SW
authors.lastname: Flynn
authors.forename: Alex L
authors.initials: AL
authors.lastname: Mackay
authors.forename: William G
authors.initials: WG
authors.lastname: Honer
mesh_terms: D000328:Adult; D061085:Agenesis of Corpus Callosum; D003337:Corpus Callosum / Q000378:metabolism*; D039721:Diagnostic and Statistical Manual of Mental Disorders; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009044:Motor Cortex / Q000033:anatomy & histology* / Q000378:metabolism; D009412:Nerve Fibers / Q000378:metabolism*; D009434:Neural Pathways / Q000378:metabolism / Q000503:physiopathology; D012559:Schizophrenia / Q000175:diagnosis / Q000378:metabolism* / Q000503:physiopathology*