A review of social neuroscience research on anger and aggression

Responding aggressively to potential threats from conspecifics is, for many organisms, a highly adaptive strategy to maintain well-being, social dominance, and resource access. Additional evidence for the role of testosterone in shaping anger and aggressive behavior in humans comes from a program of research associating testosterone levels with observer-rated violence and aggressive antisocial behavior in male and female prison populations. In humans, angry faces serve as threat signals in social dominance contexts, with extended gaze and eye contact indicating that the facial expression is automatically evaluated as a dominance challenge. Recent research suggests that the aggression-enhancing and fear-reducing effects of testosterone may have two distinct neurochemical mechanisms. Transcranial direct current stimulation (tDCS) was applied to examine the interrelations between left-sided cortical asymmetry, anger, and aggression. Neuroimaging, psychophysiological, and clinical population studies provide convergent evidence that social aggression is underpinned by hormonally driven imbalances within and between subcortical and cortical levels of the brain.