Event-related potential patterns and gender effects underlying facial affect processing in schizophrenia patients.

This study was designed to clarify the consecutive temporal mechanisms and gender effects underlying facial affect processing in patients with schizophrenia and normal controls through electrophysiological measurements. The following four event-related potential (ERP) components were chosen as indexes of four distinct stages: P100, N170, N250, and P300. A total of 38 schizophrenia patients (22 females) and 38 normal controls (20 females) were recruited. ERPs were recorded while participants identified emotions in images of faces showing three different states: happy, fearful and neutral. The mean peak amplitude of N170 was significantly lower in schizophrenia patients than in normal controls. The mean peak amplitudes of N170 and N250 for fearful emotion were significantly higher than that for happy emotion. The latencies of N170, and P300 were longer in schizophrenia patients than in normal controls. Gender effects were found for P100 peak amplitude and N170 latency, and significant interactions with gender were found for P300 amplitudes and P100 latency. Our results provide evidences of the dysfunctional ERP patterns underlying facial affect processing in schizophrenia patients. Furthermore, the results suggest that gender could be an important controlling factor for facial affect processing in schizophrenia patients.