Aggressive behavior toward rival group members increases activity in the brain's reward circuit
As social animals, humans tend to form groups that can range in size from a few individual members to entire nation-states. Historically and through the present day, human groups frequently come into conflict. A noted feature of human intergroup conflict is the proclivity of ingroup members—that is, members recognized as being part of a particular group—to inflict harm upon those considered to be non-members who are part of an outgroup. A new study may help explain the motivation for this hostility. The study found that aggression directed at rival group members increases activity in certain brain regions that are associated with feelings of reward and pleasure. Investigating this potential link further could deepen our understanding of the origins of intergroup aggressiveness and suggest interventions for curbing group-based violence. See also: Aggression; Brain; Motivation; Sociobiology