An ERP study on the time course of emotional face processing.

Using event-related brain potentials (ERPs), we investigated the time course of facial expression processing in human subjects watching photographs of fearful and neutral faces. Upright fearful faces elicited a frontocentral positivity within 120 ms after stimulus presentation, which was followed by a broadly distributed sustained positivity beyond 250 ms post-stimulus. Emotional expression effects were delayed and attenuated when faces were inverted. In contrast, the face-specific N170 component was completely unaffected by facial expression. We conclude that emotional expression analysis and the structural encoding of faces are parallel processes. Early emotional ERP modulations may reflect the rapid activation of prefrontal areas involved in the analysis of facial expression.