Abnormalities of cingulate cortex in antipsychotic-naïve chronic schizophrenia

While several morphometric studies have postulated a critical contribution of the cingulate cortex (CC) to the pathophysiology of schizophrenia based on abnormalities in CC volume, other studies have been inconclusive. Most such studies have focused only on changes in cortical volume, whereas other morphometric parameters such as surface area and cortical thickness could be more relevant and possibly account for these discrepancies. Furthermore, factors such as antipsychotic drug use and treatment duration may also influence cortical morphology. To clarify the association between schizophrenia and CC deficits, we investigated morphometric abnormalities of the CC in antipsychotic drug (AD)-naïve chronic schizophrenia patients by comparing T1-weighted magnetic resonance images (T1WI-MRI) from patients (n=17) to healthy controls (n=17) using the surface-based morphometry program FreeSurfer. Partial correlations were examined between abnormal morphometric measures and both clinical variables and cognitive performance scores. Compared to healthy controls, drug-naïve schizophrenia patients exhibited significantly lower volumes in both left rostral anterior CC (rACC) and left posterior CC (PCC). These reductions in CC volume resulted from reduced surface area rather than reduced cortical thickness. There was also a significant relationship between left PCC volume and working memory in patients. No significant correlations were observed between CC volume and clinical variables. The results suggest that abnormalities in the CC as manifested by reduced surface area may contribute to cognitive dysfunction in schizophrenia. This article is part of a Special Issue entitled SI: PSC and the brain.