Aggression differentially modulates brain responses to fearful and angry faces: an exploratory study.

Aggression is reported to modulate neural responses to the threatening information. However, whether aggression can modulate neural response to different kinds of threatening facial expressions (angry and fearful expressions) remains unknown. Thus, event-related potentials were measured in individuals (13 high aggressive, 12 low aggressive) exposed to neutral, angry, and fearful facial expressions while performing a frame-distinguishing task, irrespective of the emotional valence of the expressions. Highly aggressive participants showed no distinct neural responses between the three facial expressions. In addition, compared with individuals with low aggression, highly aggressive individuals showed a decreased frontocentral response to fearful faces within 250-300 ms and to angry faces within 400-500 ms of exposure. These results indicate that fearful faces represent a more threatening signal requiring a quick cognitive response during the early stage of facial processing, whereas angry faces elicit a stronger response during the later processing stage because of its eminent emotional significance. The present results represent the first known evidence that aggression is associated with different neural responses to fearful and angry faces. By exploring the distinct temporal responses to fearful and angry faces modulated by aggression, this study more precisely characterizes the cognitive characteristics of aggressive individuals.