Neural responses to faces reflect social personality traits.

Faces are a developmentally primary and critically important source of social information, and they are processed differently from most other visual percepts. Studies of brain electrophysiology reveal a face-sensitive component, the N170, which is typically enhanced to faces relative to other stimuli. Research in social disabilities suggests that an atypical N170 response in this population may stem from decreased developmental exposure to faces secondary to reduced social interest. Here we examined the relationship between neural responses to faces and social personality characteristics in a normative sample. Participants were pre-screened to identify individuals scoring high on extraversion or introversion. Both groups were presented with upright and inverted face stimuli. An inversion effect, a marker of expertise for faces, was observed in people with high extraversion but not in those with high introversion. These findings suggest that, within typically developing populations, social attitudes are reflected in the neural correlates of face perception.