Aggression

Chapter summary

It is important to distinguish between reactive aggression (triggered by anger) and proactive aggression (triggered by the prospect of some desired outcome).

There is also an important distinction between physical and relational aggression. The latter is more subtle (e.g., gossiping about someone) and is used to reduce someone else’s social status.

The apparent decline in human violence over the past century may be due to the existence of nuclear weapons rather than any civilising process. Cultures with very low levels of aggression and violence have social norms emphasising cooperation and the disadvantages of competition.

One situational factor causing anger and aggression is a frustrating event (providing someone else is perceived as blameworthy). Another situational factor involves observational learning: if someone else is seen to be rewarded for behaving aggressively, this can lead the observer to imitate that behaviour.

Other situational factors that can cause aggressive behaviour are being exposed to violent media and playing violent video games. However, the negative effects of playing violent video games are relatively small.

Children’s aggressive behaviour is determined in part by family processes (e.g., coercive cycles).

Schoolchildren can be strongly influenced by their classroom peers. Initially non-aggressive children become more aggressive over time when they find themselves in a classroom with a high average level of aggression. This supports the notion that aggressive behaviour can spread like a contagion.

138Twin studies indicate that 50% of individual differences in aggression are due to genetic factors. The figure is 65% for physical aggression, about 40% for proactive aggression, and 30% for reactive aggression.

There are no gender differences in anger or relational aggression. However, males exhibit higher levels of physical aggression than females (especially for very violent forms of physical aggression.

The general aggression model provides the most comprehensive account of the distal (e.g., personality; genetic risk factors) and proximal (e.g., cognitions; arousal) factors influencing aggressive behaviour.

The general aggression model provides a framework rather than a theory, because it is relatively uninformative about the complex interactions that occur among the numerous factors incorporated within it.

Intervention strategies are generally more effective than prevention strategies in reducing children’s aggression.

Child-based intervention strategies (e.g., social competence training) have beneficial effects. However, parent-based intervention strategies (e.g., those designed to reduce coercive cycles within families) reduce childhood aggression to a greater extent.