Effect of facial affect stimuli on auditory and visual P300 in healthy subjects

This study investigated whether or not P300 components are influenced by emotional affect such as sadness and pleasure in twenty healthy subjects and whether or not the P300 effects of facial affect stimuli are influenced by auditory and visual stimulus modalities. Written informed consent was taken from each subject before the study. Each subject was asked to stare at a simple picture of a facial expression (crying or smiling faces) during the auditory and visual oddball tasks. P300 amplitude and area were significantly larger when viewing a crying face (sadness) than a smiling face (pleasure) under both conditions with auditory and visual stimulus. P300 latency was significantly longer while viewing sadness than while viewing pleasure only with auditory stimuli. Reaction time was not changed by facial stimuli. Amplitude and area of P300 were significantly larger in women than men in their modalities, but the effects of facial affect on P300 amplitude and area in women were similar to those in men. These results suggest that amplitude and area of P300 with both modalities recorded while viewing sadness may induce larger attentional resource than pleasure. Gender was a less potent influence of facial expression on P300 parameters. The influence of facial emotion may be important to investigate the recognition processes of subjects.