Background: Studies have reported premorbid as well as postonset social dysfunction in schizophrenia. This impairment has also been observed to emerge after lesions in the ventral aspect of the frontal cortex (i.e., straight gyrus and orbitofrontal cortex).
Methods: Magnetic resonance imaging scans were obtained from 45 male patients with schizophrenia and 45 matched control subjects. Cortical gray matter volume and surface area were determined for the ventral frontal cortex (VFC), subdivided into the orbitofrontal cortex (OFC) and the straight gyrus (SG).
Results: The global measures of gray matter volume and surface area in the VFC was not significantly different between patients and control subjects; however, there was a regional difference, with the right SG volume and surface area being smaller in patients compared with control subjects. Volume of the VFC had an inverse correlation with measurements of both premorbid and postdiagnosis social function. The smaller the gray matter in these regions, the greater the social dysfunction. There was no relationship between morphology of this brain region and any other clinical variable.
Conclusions: Morphology of the VFC is directly related to abnormal social function in schizophrenia, including measures of social dysfunction that predate the onset of illness.