Abstract

This research examined the effects of extraversion on event-related potential(ERP) in response to both social and emotional stimuli. Experimental participants were assigned to either extraverts or introverts by the EPQ-R. Twelve pictures presenting four happy, four fear and four neutral faces were used as social stimuli and twelve building pictures were used as nonsocial control stimuli. The P300 component of the ERPs elicited by both human faces and buildings were analysed. Participants exhibited higher P300 amplitudes to human faces compared to buildings. Faces elicited significantly higher P300 amplitudes in extraverts than those in introverts, but buildings did not. There were no significant differences in the P300 amplitude for different facial expressions. This finding suggests that the enhanced motivational significance to social stimuli for extraverts is associated with the individual difference in underlying neural processes.