1. Aggression

2. Aggression is any behavior, whether physical or verbal, intended to hurt another. Example—Using sarcasm to put another person down is aggressive behavior.
Hostility (or hostile aggression) results from frustration and is not necessarily intended to produce benefits. Example—Being mean to a person you do not know just for the sake of being mean is hostile behavior.
Instrumental aggression is aggression used to gain some personal benefit. Example— Putting someone down to make you feel better is instrumental aggression.

3. Examples of Aggression and Antisocial behavior
The general aggression model (GAM) suggests that aggression is the result of multiple psychological processes. The GAM takes into account situational variables, aggressive thoughts and feelings, arousal, appraisal or interpretation, and behavior choice.
Biomedical explanations:
Genetic influences—One study found that the prefrontal area of the cortex metabolized glucose at a significantly slower rate in murderers than those who do not kill. This may result in a decreased ability to control aggressive impulses, as well as a lack of judgment.

4. Brain damage influences on the limbic system (hypothalamus and amygdala): Researchers found that damage to these structures may produce defensive aggression, which includes heightened aggressiveness to stimuli that are not usually threatening or decreases in the responses that normally inhibit aggression.
Drugs—Alcohol can increase antisocial and aggressive behavior. For example, alcohol myopia (alcohol “nearsightedness”) can impair a person’s perception and thoughts and make social responses more extreme.

6. Learning explanations:
Social learning theory suggests that people learn responses, including aggressive responses, by observing other people.
Modeling—When violent behavior is displayed in the home or by authority figures, children learn to imitate the negative behavior. Bandura, et al. (1961) found that children who watched an authority figure pummel a BoBo doll were more likely to be aggressive toward the BoBo doll than were children who did not see an authority figure act aggressively toward a BoBo doll.
Another example—Children who watch all-star wrestling and then mimic the wrestling moves with their siblings demonstrate modeling behavior.

8. Environmental Conditions
Frustration—aggression hypothesis: Frustration produces readiness to respond aggressively; environmental cues that are associated with aggression can lead to aggressive behavior. Neither frustration nor the cues (e.g., guns) alone can explain aggressive behavior (e.g., race riots).
Environmental stress (air pollution, noise, crowding, etc.) can influence aggressive behavior. Heat, for example, increases aggression. Example—Hurricane Katrina survivors who waited at the crowded Superdome in New Orleans for evacuation became aggressive.
Cultural influences—The acceptability of violence and antisocial behavior varies greatly between cultures. (a) Culture may influence the use of firearms or whether disputes are solved through adjudication versus confrontation.

9. Media Influences
This is the idea that those who are exposed to numerous violent influences through film, television, and video games will be more likely to engage in violent behavior. Huesmann and Eron (1986) found that children who watched more violent television and who identified with aggressive characters were more aggressive compared to other children. Those children were later found to be more aggressive than their peers in their early 20s as well.
Studies have also examined the correlation between interactive violent video games and aggressive behavior. While research conclusions vary, studies of young children have revealed that children are more aggressive after they play an aggressive video game than they are when they play a nonaggressive video game

11. Generalized Arousal
Transferred excitation can make aggressive behavior more likely when there is a reason, opportunity, or target for aggressive behavior. Because of this phenomenon, police often increase their presence at certain sporting games (e.g., games for a coveted title or games between teams with a history of rivalry).
Excitation transfer—Arousal can lead to aggression. Researchers found that when participants engaged in a procedure that elicited anger and then were physiologically aroused, they behaved more aggressively than other participants who were not exposed to both arousing conditions.
The cognitive neoassociation model of aggression predicts that negative or unpleasant events activate anger and fear (fight or flight) and that our decision to act aggressively or not depends on situational cues.

13. Aggression in children, close relationships, and groups
Some children use aggression (physical or verbal) to control peers. School bullies tend to use physical or verbal aggression on certain peers.
Violence can occur in close relationships, whether between partners or between parents and children. One study estimated that more than 25% of intimate couples have at least one physically aggressive episode in the relationship.
Mob violence occurs when people in a group act aggressively. This violence is often unplanned and is typically triggered by events that make people angry.