Objective: There is some evidence of thalamic abnormalities in schizophrenia. This study investigated thalamic volumes in patients experiencing their first episode of psychosis and nonpsychotic comparison subjects.
Method: Magnetic resonance imaging scans were obtained for 38 patients and 29 comparison subjects. Patients' symptoms were rated by research psychiatrists using the Positive and Negative Syndrome Scale.
Results: Thalamic volumes were smaller in patients than in comparison subjects. There were no significant correlations between thalamic volumes and symptom scores.
Conclusions: Thalamic abnormalities are present close to the onset of psychosis.