Researchers compare the volumes of various regions of the brain in people with and without schizophrenia to identify the key brain structures involved.

Schizophrenia is a complex mental disorder and a major healthcare burden. Because current treatments are often ineffective, there is a need for a better understanding of the biology of the brain in order to improve treatment options. Enlargement of brain ventricles and lower volumes of grey matter are two well-established markers of schizophrenia. On average, these measurements are significantly different between patients with schizophrenia and those without schizophrenia. However, developing evidence indicates that structural differences in the key brain structures involved in schizophrenia can vary quite a lot among patients.

To determine if schizophrenia is truly linked to higher variability in brain structures, investigators from England conducted an analysis of data from previous studies that reported on schizophrenia brain structures in patients with schizophrenia compared to healthy control subjects. The research was recently published in JAMA Psychiatry. After combing through medical databases, a total of 108 studies were included in this analysis. These studies comprised a total of 3,901 patients with first-episode schizophrenia and 4,040 healthy controls.

The investigators found a significantly larger variability in volumes of the putamen, temporal lobe, thalamus, and third ventricle regions of the brain in patients with schizophrenia compared to healthy subjects. Patients with schizophrenia also had larger average volumes of the lateral and third ventricles of the brain. Conversely, average volumes of the amygdala, frontal lobe, temporal lobe, and thalamus were smaller in patients with schizophrenia. Both the variability and volume of the anterior cingulate cortex were significantly lower in patients with schizophrenia.

These findings suggest that key biological processes underlying schizophrenia may be overlooked by just comparing average measurements of brain ventricles and grey matter between patients and healthy controls. The lower variability and average volume of the anterior cingulate cortex suggest that it is a key region affected by schizophrenia.