aggression

Aggression refers to a range of behaviors aimed at harming or injuring others, including physical assault, verbal threats, or social exclusion. It can be direct or indirect, and may be instrumental or reactive. It is not synonymous with anger, competitiveness, or self-defense, though these states can precede or accompany aggressive acts.

Direct aggression involves overt actions toward a target, such as hitting or shouting. Indirect aggression harms social relationships or status, such as gossip or social exclusion. Reactive aggression is a response to perceived threat or frustration; proactive, instrumental aggression is undertaken to achieve a goal.

In humans, aggression is studied across biological, psychological, and social dimensions. Biological factors include genetics, neuroanatomy, and hormones. Brain circuits involving the amygdala and prefrontal cortex, and neurotransmitters such as serotonin and testosterone, influence impulsivity, threat processing, and control. Psychological factors include emotion regulation, perceived injustice, attributional style, learned behavioral scripts, and exposure to violence. Sociocultural factors include cultural norms, gender roles, social learning, media representations, and environmental stressors.

Developmentally, aggression often emerges in early childhood and can follow stable or changing trajectories. Risk factors include maltreatment, exposure to violence, poverty, substance use, and poor executive functioning. Evolutionary analyses suggest aggression can have adaptive value in resource defense, mate competition, or social dominance in certain contexts.

Consequences include personal injury and escalation of conflict, as well as social, legal, and health costs. Prevention and intervention approaches encompass cognitive-behavioral strategies, anger management, parent training, school and community programs, and environmental modification to reduce stressors and provocation.