Changes in auditory P300 with clinical remission in schizophrenia: effects of facial-affect stimuli.

The auditory P300 is affected by arousal and emotion. We examined the effect of drawings expressing sadness or pleasure on auditory event-related potentials (ERP) during recovery from schizophrenia. Oddball-paradigm auditory ERP were recorded while presenting one of these drawings to nine patients with paranoid schizophrenia and seven patients with other types of schizophrenia during the acute stage and again during remission. P300 parameters (amplitude, area, and latency), reaction time, and symptom scores were evaluated. P300 amplitude and area were significantly greater in the recovery than in the acute phase. Increases were larger when viewing drawings that expressed sadness than when viewing drawings that expressed pleasure. In paranoid-type patients, P300 when viewing pleasurable drawings was similar to that when viewing sad drawings during the acute phase; in remission, P300 was significantly larger when viewing sad drawings than when viewing pleasurable drawings. In non-paranoid patients, P300 while viewing pleasurable drawings was significantly larger than that while viewing sad drawings during the acute phase; this difference disappeared during recovery. P300 latency and reaction time were not influenced by facial-affect stimuli or recovery. A significant negative correlation was noted between amplitude and negative symptom scores. P300 amplitude and area may be useful state markers during recovery in schizophrenic patients. Effects involving attention resources and emotional arousal are also involved.