Objective: To investigate spatial and temporal patterns of event-related potentials (ERP) evoked by facial expression.
Methods: ERP was recorded in 25 healthy subjects while they performed facial recognition task. Repeated-measure one-way ANOVA was adopted to compare the subjects' responses to stimulation by 3 different expressions (positive, neutral and negative) with statistical parametric mapping (SPM).
Results: Significant facial expression effects occurred separately in the left parietal and bilateral occipital regions (280-340 ms), left frontal region (400-420 ms), and right prefrontal region (480-500 ms). In 4 time periods, significant difference was observed between positive and neutral emotion wave in the right frontoparietotemporal and left prefrontal regions (60-80 ms), right occipital region (120-140 ms), left occipital region (280-320 ms), and left frontoparietal region (400-440 ms). Significant difference between negative and neutral emotion waves was observed in 5 time periods in the right occipital region (120-140 ms), central frontoparietal region (220-240 ms), central parietal region (280-300 ms), left parietal and right temporopartial regions (320-340 ms) and frontopartial occipitotemporal region (480-500 ms).
Conclusions: The spatiotemporal patterns of ERP suggest that the information processing of facial expression involves extensive brain regions dynamically.