Cognitive and motor impairments are related to gray matter volume deficits in schizophrenia

This study examined whether the neuropsychological deficits observed in patients with schizophrenia were related to cortical gray matter volume deficits in these patients. All subjects were men and included 34 patients with DSM-III-R Schizophrenia and 47 age-matched healthy controls. Subjects received a battery of 21 tests, assessing four different functional domains: executive functions, short-term memory and production, declarative memory, and motor ability. MRI volumes were corrected for normal variation in head size and age, and neuropsychological test scores were corrected for normal variation in age. The schizophrenic group had significantly smaller cortical gray matter volumes (p< .05) and lower test scores in all functional domain than the control group (p = .0001). Within the schizophrenic group, lower scores in each domain were significantly correlated with smaller total cortical gray matter volumes; however, no predictable relationships were observed between neuropsychological test performance and the volumes of specific cortical regions.