Difficulty: Intermediate | Prerequisites: None.
Aggression is intentional behaviour aimed at causing harm. It comes in several forms (physical vs. social, hostile vs. instrumental) and is explained by biological factors (brain regions, hormones), psychological theories (frustration-aggression, aggressive cues, social learning) and cultural factors (culture of honour). Viewing violent media is consistently linked to increased aggression through both correlational and longitudinal evidence.
Aggression
Physical or verbal behaviour intended to cause harm. In simple terms, any deliberate act meant to hurt someone.
Violence
Aggression that has extreme physical harm as its goal. All violence is aggression, but not all aggression is violence.
Physical aggression
Hurting someone's body (hitting, kicking).
Social / relational aggression
Hurting someone's feelings or threatening their relationships (spreading rumours, exclusion).
Instrumental aggression
Aggression used as a means to some other end. Think of it as calculated harm: the goal is not the injury itself but what the injury achieves (e.g. terrorism).
Hostile aggression
Aggression that springs from anger, where the goal is simply to injure.
Frustration-aggression theory
Based on Freudian drive concepts: aggression is always a result of frustration (the blocking of goal-directed behaviour). Too simplistic on its own to fully explain human aggression.
Aggressive cues theory
A revision of frustration-aggression theory. Frustration creates readiness for aggression, but additional environmental cues (objects associated with aggression) are needed to trigger it.
Social learning theory
We learn aggression not only by experiencing its payoffs but also by observing others. Includes direct reinforcement (active, passive, instrumental) and observational learning.
Culture of honour
A cultural pattern, especially in the American South, where small disputes become contests for reputation and social status, and insults demand an aggressive response to restore honour.
Aggression vs. violence: aggression is the broader category (intentional harm); violence is the extreme subset (extreme physical harm as the goal).
Physical vs. social: physical aggression targets the body; social/relational aggression targets feelings and relationships.
Instrumental vs. hostile: instrumental aggression is a means to an end; hostile aggression springs from anger with injury as the goal.
Aggression is partly genetic and species-typical, providing a survival and reproductive advantage. However, biological accounts alone cannot explain the variety of aggression forms across humans or geographic differences in aggression rates.
Neural basis
Aggression is controlled by multiple brain regions. Stimulating the hypothalamus and amygdala can both produce aggressive responses.
PET-scanning study: compared brains of 41 convicted murderers with matched controls. Murderers showed different glucose uptake in prefrontal areas (associated with low self-control), corpus callosum (difficulties integrating complex information) and parietal cortex (difficulties forming complex concepts).
Hormones
Human aggressiveness correlates with testosterone, though the effect on behaviour is smaller in humans than in animals.
Both correlational and causal data support a link between testosterone and aggression.
Competitive settings increase testosterone, which may regulate sensitivity to status and risk valuation.
Aggression is always a result of frustration. Frustration is the blocking of goal-directed behaviour. It grows when motivation is strong, gratification was expected and the blocking is complete.
Why it fails on its own: a study had participants complete a group decision task with a short time limit. A confederate kept asking repeated questions, causing the group to fail. In the "arbitrary frustration" condition, the confederate was just being difficult; in the "non-arbitrary" condition, the confederate wore a hearing aid (justifying the repeated questions). Results: more aggression in the arbitrary frustration condition (rejection of group member for a future task). Frustration alone is too simplistic; whether the frustration feels unjustified matters.
A revision of frustration-aggression theory: frustration creates readiness for aggression, but environmental cues associated with aggression are needed to trigger it. Cues facilitate aggression through their association with aggression concepts and aggressive behavioural scripts.
Study: participants' aggressive driving behaviours were observed in a physical driving simulator. A gun or a tennis racket was placed in the seat next to them. Results: more aggressive behaviours with the gun prime compared to the tennis racket prime.
Strength: explains why the same person can be aggressive in one situation and not another. Limitation: does not address how people acquire aggressive associations in the first place.
We learn aggression by experiencing its payoffs and by observing others.
Direct reinforcement: active (praise for fighting), passive (attention for fighting), instrumental (fighting works to get what you want).
Observational learning: watching others be aggressive teaches how to aggress and reveals reinforcement contingencies.
Bandura's Bobo doll studies
Children observed an adult playing with a Bobo doll either violently or non-violently. Children were then frustrated and placed in a room with other toys, including a Bobo doll.
Results: children who observed aggressive models played more aggressively. Children tended to copy same-sex models more than other-sex models.
Supports social learning theory: aggression is acquired through observation, not only personal experience.
In the American South, small disputes can become contests for reputation and social status. People in honour cultures are relatively more bound by norms requiring aggressive responses to insults.
Study: following a small insult, Southern participants experienced a larger increase in testosterone than Northern participants. Insulted Northern participants showed no significant change. In a "game of chicken" scenario, control (non-insulted) Southerners gave way very early, anticipating and avoiding honour-related conflict. Insulted Southerners were very reluctant to give way, attempting to restore their sense of honour.
Frustration-aggression theory predicts a negative relationship (catharsis). Social learning theory predicts a positive relationship (modelling, imitation; TV violence is often rewarded).
Correlational evidence
Spike in US homicides three days after televised prize fights. More publicised fights had a larger effect. Evidence for victim modelling: if the white fighter lost, murders of White people went up.
Longitudinal evidence
15-year follow-up of 329 children. Measured childhood levels of aggression, violent TV watching, perceived realism of TV violence and identification with violent TV actors.
Correlations: the more violent TV watched as a child, the more realistic TV violence was perceived to be, and the more a child identified with a same-sex violent actor, the more violent the person was as an adult.
Takeaway: childhood TV violence exposure has effects that persist into adulthood. What matters is how the child perceives and engages with the content, not just the volume of exposure.
Students often think frustration always leads to aggression. The frustration-aggression hypothesis in its original form is too simplistic. Whether aggression follows frustration depends on whether the frustration feels arbitrary (unjustified) and on the presence of aggressive cues.
Students often think the Bobo doll studies only show that children imitate violence. They also show that children are selective: they copy same-sex models more than other-sex models, and aggression is learned through observation even without direct reinforcement.
Students often assume the culture of honour only affects behaviour during conflict. The study showed that even control (non-insulted) Southerners behaved differently from Northerners, giving way early to avoid honour-related escalation.
⚠️ Know the four types of aggression (physical/social, instrumental/hostile) with examples.
⚠️ Be able to describe a biological, a frustration-based, a cues-based and a social learning explanation of aggression, each with at least one study.
⚠️ Be prepared to explain why frustration-aggression theory is insufficient and describe the study that shows this.
⚠️ The Bobo doll study is a frequently tested example for social learning theory.
⚠️ Be ready to describe both correlational and longitudinal evidence linking TV violence to aggression.
Fill in the blank: Violence is a subset of aggression where extreme _____ harm is the goal. (physical)
True or False: Aggressive cues theory predicts that frustration alone is sufficient to produce aggression. (False. Environmental cues are also needed.)
True or False: In the Bandura Bobo doll study, children who observed a non-violent adult model also played aggressively. (False. Only children who observed aggressive models played more aggressively.)
Fill in the blank: In the culture of honour study, insulted Southern participants showed a larger increase in _____ than insulted Northern participants. (testosterone)
Q: Describe aggressive cues theory and explain one study supporting it.
A: Aggressive cues theory is a revision of frustration-aggression theory. It holds that frustration creates a readiness for aggression, but additional cues in the environment (objects or stimuli associated with aggression) are needed to trigger it. In a driving simulator study, a gun or a tennis racket was placed next to participants. Those with the gun prime drove more aggressively than those with the tennis racket. The gun served as an aggressive cue, activating aggression-related concepts and behavioural scripts.
Q: Describe the culture of honour theory and one study supporting it.
A: The culture of honour holds that in the American South, small disputes become contests for reputation and social status. Following a minor insult, Southern participants showed larger testosterone increases than Northern participants. In a game of chicken scenario, non-insulted Southerners gave way early (avoiding honour conflict), while insulted Southerners refused to give way, attempting to restore their sense of honour.
Q: What does social learning theory predict about TV violence and aggression? Describe one piece of longitudinal evidence.
A: Social learning theory predicts a positive relationship: watching violence teaches aggressive behaviour through modelling. A 15-year follow-up of 329 children found that the more violent TV watched as a child, the more realistic TV violence was perceived and the more a child identified with a same-sex violent actor, the more violent the person was as an adult. Childhood exposure had lasting effects into adulthood.
Frustration-aggression and aggressive cues theory connect to emotional arousal concepts in the persuasion and liking/attraction modules. Social learning theory connects to broader learning principles that also explain how stereotypes and prejudice are acquired. The culture of honour links to norms and social identity, which are central to understanding group influence and conflict resolution.
Aggression, violence, physical aggression, social aggression, relational aggression, instrumental aggression, hostile aggression, frustration-aggression theory, aggressive cues theory, weapons effect, gun prime, social learning theory, Bandura, Bobo doll, observational learning, culture of honour, honor, testosterone, PET scan, prefrontal cortex, amygdala, hypothalamus, media violence, TV violence, longitudinal study, NYU social psychology