Corpus callosum shape and size in male patients with schizophrenia

Corpus callosum (CC) morphology has recently been investigated in schizophrenia using refined imaging and analytic techniques; however, methodological problems and small sample sizes have led to inconsistent findings.

This study used a large sample of male schizophrenics (n = 79) and male controls (n = 65) to investigate size and shape of the CC on midsagittal magnetic resonance images. Size was determined by tracing the area of the CC, and shape was determined using a landmark-based analysis. In addition, the relationship between CC morphology and phenomenologic variables such as age of onset, length of illness, exposure to medications, and symptom severity was explored.

After controlling for age, height, and parental socioeconomic status, there was a main effect of diagnosis on CC size (F = 5.05, df = 1,139, p < .03), with patients' CCs being significantly smaller. No difference was found between patients and controls in CC shape (F = 1.07, df = 18,125, p > .38) or orientation (F = 0.79, df = 18,125, p > .70), using a landmark-based technique. Finally, there was a significant inverse correlation between size of CC and severity of negative symptoms.

These findings support previous studies that have found a decrease in size of the CC in patients with schizophrenia. Moreover, the decrement in volume is generalized, not regional, and is related to the severity of negative symptoms.