Reduced emotional response of schizophrenic patients in remission during social interaction.

Inappropriate emotional response during social interaction is a prominent feature of schizophrenia during the acute stage of illness. This study evaluates the course of reduced facial activity in schizophrenic patients in remission and compares it with healthy controls. The experimental conditions included watching two films, one inducing happy and the other sad emotional states. Each is followed by an interview eliciting happy and sad feelings. The facial actions were recorded (1) by a computer-based analysis of recordings of the skin movement and (2) by electromyography of the corrugator and zygomaticus muscles. Twenty schizophrenic patients in remission and 20 normal controls participated in the study. In contrast to previously studied acute patients, there was no overall reduction of facial expression in the upper face of schizophrenic patients in remission. Patients showed fewer movements (automatic analysis) of the lower face during the happy interview and more movements during the sad interview compared with controls. Furthermore, schizophrenic patients showed reduced zygomaticus activity (EMG) during both the happy film and the interview, suggesting a reduced ability of schizophrenic patients to express happy facial expressions, such as smiling, in the lower face. This may indicate a reduced variability in emotional response in schizophrenia.