A study of brain structural changes analyzed schizoaffective disorder, and how similar they are to those seen in schizophrenia and bipolar disorder. A group of healthy control subjects was compared with each patient group and discovered that patients with schizophrenia and schizoaffective disorder had coinciding and widespread volume reduction in the brain. Other patients with bipolar disorder did not have these significant reductions in volume. Further analysis uncovered that patients with schizoaffective disorder tended to show a widespread area of gray matter reduction similar to the schizophrenia patient observations. Observed gray matter reductions were more extreme in patients with schizoaffective disorder and schizophrenia than those with bipolar disorder. This suggests that schizoaffective disorder more closely resembles schizophrenia than bipolar disorder (in terms of structural gray matter brain imbalances and abnormalities).