People have a fundamental need to belong that, when satisfied, is linked to a variety of indicators of well‐being. The current article discusses what happens when social relationships go awry, namely through social exclusion. It seeks to resolve discrepancies in the literature by proposing that responses to social exclusion depend primarily on the prospect of social acceptance. When people feel socially excluded, they want to regain acceptance and thus may respond in ways that can help them do so. When the possibility of acceptance is not forthcoming, however, socially excluded people become selfish and antisocial. Evidence for this pattern was found at behavioral, cognitive, and biological levels. The motivation to gain acceptance may drive people to engage in negative health behaviors, such as smoking. Thus, excluded people demonstrate sensitivity to possible social acceptance, but they can exude an air of selfishness and hostility when there is no possibility of satisfying their need to belong.

Social rejection often increases aggression, but the neural mechanisms underlying this effect remain unclear. This experiment tested whether neural activity in the dorsal anterior cingulate cortex (dACC) and anterior insula in response to social rejection predicted greater subsequent aggression. Additionally, it tested whether executive functioning moderated this relationship. Participants completed a behavioral measure of executive functioning, experienced social rejection while undergoing functional magnetic resonance imaging and then completed a task in which they could aggress against a person who rejected them using noise blasts . We found that dACC activation and executive functioning interacted to predict aggression. Specifically, participants with low executive functioning showed a positive association between dACC activation and aggression, whereas individuals with high executive functioning showed a negative association. Similar results were found for the left anterior insula. These findings suggest that social pain can increase or decrease aggression, depending on an individual's regulatory capability.

Past research has established that loneliness is associated with both self-concept confusion and depression. The present work ties these disparate lines of research together by demonstrating that self-concept confusion mediates the relationship