Difficulty: Intermediate | Prerequisites: Social identity, attitudes, and basic group processes (Chapters 7–8)
Prejudice (Chapter 9) and Aggression (Chapter 10) explore the darker side of social behaviour. Prejudice covers why people hold negative attitudes toward out-groups, how stereotypes form and persist, and what interventions can reduce bias. Aggression examines the biological, psychological, and social roots of harmful behaviour. Both chapters draw heavily on social identity theory and social learning theory introduced earlier in the course. Understanding these topics is essential for the later chapters on helping behaviour and conflict resolution.
Prejudice arises from cognitive shortcuts (stereotypes), emotional reactions, and group-based motivations (social identity), and can be reduced through intergroup contact under the right conditions. Aggression is multiply determined by biology, frustration, learned behaviour, and situational triggers, with media exposure playing an increasingly studied role.
Prejudice
A preconceived negative attitude toward a group and its members, not based on actual experience. Prejudice involves an affective (emotional) component, a cognitive component (stereotypes), and a behavioural component (discrimination). Think of it as: a ready-made dislike for a group before you have met its members.
Stereotype
A generalised belief about the attributes of a group of people. Stereotypes are cognitive shortcuts that simplify a complex social world, but they often lead to inaccurate judgements about individuals. In simple terms, this means assuming everyone in a group shares the same characteristics.
Discrimination
Unjustified negative behaviour toward a group or its members. Discrimination is the behavioural expression of prejudice.
Social identity theory
Tajfel and Turner's theory that people derive self-esteem from their group memberships and are motivated to see their in-group as superior to out-groups. This in-group favouritism drives much of intergroup prejudice.
Realistic conflict theory
Sherif's theory that prejudice arises from competition between groups over scarce resources. When groups compete, hostility develops; when they cooperate toward shared goals, hostility diminishes.
Implicit bias
Automatic, unconscious attitudes or stereotypes that affect understanding, actions, and decisions. Measured through tools such as the Implicit Association Test (IAT). Think of it as: prejudice operating below the radar of conscious awareness.
Implicit Association Test (IAT)
A computer-based measure that assesses the strength of automatic associations between concepts (e.g. race and positive/negative words) by measuring response times.
Contact hypothesis
Allport's idea that intergroup contact under certain conditions (equal status, common goals, institutional support, cooperative interaction) can reduce prejudice.
Stereotype threat
The anxiety experienced by members of a stereotyped group when they fear confirming a negative stereotype about their group, which can impair performance on relevant tasks.
Out-group homogeneity effect
The tendency to perceive members of an out-group as more similar to one another than members of one's own in-group. In simple terms: "they're all the same; we're all different."
Tajfel's minimal group studies: even when people are assigned to groups on trivial bases (e.g. preference for one abstract painting over another), they immediately show in-group favouritism.
Social identity theory explains this: our self-concept is partly derived from the groups we belong to. Favouring the in-group boosts self-esteem.
In-group favouritism does not require hostility toward the out-group, though it often produces relative disadvantage for out-group members.
Sherif's Robbers Cave experiment (1954): boys at a summer camp were divided into two groups. Competition over scarce resources (prizes, camp facilities) produced intense hostility. Cooperation on superordinate goals (problems that required both groups to work together) reduced hostility.
Realistic conflict theory explains prejudice at the group level: when groups perceive themselves as competing for jobs, housing, or political power, prejudice intensifies.
Categorisation: the human tendency to sort people into groups (us/them) is automatic and begins early in development.
Stereotypes serve as cognitive shortcuts. They are resistant to change because people attend to confirming information (confirmation bias) and explain away exceptions (subtyping).
Out-group homogeneity effect: "they" all seem alike, while "we" are a diverse collection of individuals. This makes it easier to apply stereotypes to out-group members.
Illusory correlation: overestimating the association between two distinctive events (e.g. a minority group and a negative behaviour), which reinforces stereotypes.
Implicit biases are automatic associations that operate outside conscious awareness. A person can hold egalitarian explicit attitudes while showing implicit bias on the IAT.
The IAT measures reaction time differences: if you associate "White" and "good" more readily than "Black" and "good," the test registers an implicit preference.
Implicit biases predict behaviour in ambiguous situations, snap judgements, and nonverbal behaviour more reliably than explicit attitudes do.
Debate continues about whether the IAT predicts discriminatory behaviour strongly enough to be used in applied settings.
Contact hypothesis (Allport, 1954): intergroup contact reduces prejudice when four conditions are met:
Equal status between the groups within the contact situation.
Common goals that require cooperation.
Institutional support (authorities endorse the contact).
Opportunity for personal acquaintance (not just surface interaction).
Extended contact effect: merely knowing that an in-group member has a close relationship with an out-group member can reduce prejudice.
Perspective-taking: actively imagining the world from another group's viewpoint reduces prejudice and increases empathy.
Stereotype threat reduction: informing test-takers that a test is not diagnostic of ability, or having them affirm valued aspects of their identity before the test, can reduce the performance-impairing effects of stereotype threat.
Desegregation policies, diversity training, and cooperative learning programmes (such as the jigsaw classroom) are all built on contact hypothesis principles. Implicit bias research informs police training, hiring practices, and healthcare disparities work.
Students often conflate prejudice, stereotypes, and discrimination. Prejudice is the attitude (affect), stereotypes are the beliefs (cognition), and discrimination is the behaviour. They are related but distinct.
The contact hypothesis does not claim that any contact between groups reduces prejudice. The four conditions (equal status, common goals, cooperation, institutional support) are essential. Casual contact without these conditions can worsen relations.
Implicit bias and explicit prejudice are not the same thing. A person can score high on implicit bias and low on explicit prejudice. The two predict different types of behaviour.
Stereotype threat does not mean that stereotypes are accurate. It describes a situational performance anxiety triggered by awareness of a negative stereotype.
⚠️ Be able to name and explain all four conditions of the contact hypothesis. This is a staple exam question.
⚠️ Know the difference between social identity theory and realistic conflict theory as explanations for prejudice.
⚠️ The IAT and implicit bias are frequently tested. Be ready to explain what the IAT measures and its limitations.
⚠️ Sherif's Robbers Cave experiment is a classic study. Know the design, findings, and how superordinate goals reduced hostility.
⚠️ Understand stereotype threat, its mechanism, and at least one intervention that reduces it.
True or false: social identity theory predicts that simply being assigned to a group is enough to trigger in-group favouritism.
Fill in the blank: the ______ hypothesis proposes that intergroup contact under specific conditions can reduce prejudice.
True or false: the out-group homogeneity effect means we see our own group as more diverse than other groups.
Fill in the blank: ______ threat describes the anxiety felt by members of a stereotyped group when they fear confirming a negative stereotype.
Answers: 1. True (Tajfel's minimal group studies). 2. Contact. 3. True. 4. Stereotype.
Aggression
Behaviour intended to harm another person who does not wish to be harmed. The key element is intent. Accidental harm is not aggression.
Hostile aggression
Aggression driven by anger, with the primary goal of inflicting harm. Also called emotional or reactive aggression. Think of it as: lashing out in the heat of the moment.
Instrumental aggression
Aggression used as a means to achieve some other goal (e.g. money, status, territory). The harm is a tool, not the objective. In simple terms, this means hurting someone to get something you want, not because you are angry.
Frustration-aggression hypothesis
The original proposal (Dollard et al., 1939) that frustration (being blocked from a goal) always leads to aggression, and aggression always stems from frustration. Later revised to say frustration creates a readiness for aggression.
Social learning theory
Bandura's theory that aggression is learned through observation, imitation, and reinforcement. The Bobo doll experiment is the classic demonstration.
Catharsis hypothesis
The idea (rooted in Freud) that expressing aggression reduces the urge to aggress further. Research has largely failed to support this; venting often increases rather than decreases aggression.
Dehumanisation
Perceiving members of another group as less than fully human, which lowers the psychological barriers to harming them.
Cultivation theory
The idea that long-term exposure to media content (especially violent media) gradually shapes viewers' perceptions of reality, making the world seem more dangerous than it is (the "mean world syndrome").
Displaced aggression
Redirecting aggression from the source of frustration to a safer or more available target. A classic example: a worker scolded by a boss comes home and snaps at a family member.
Weapons effect
Berkowitz's finding that the mere presence of a weapon (e.g. a gun on a table) can increase aggressive behaviour by priming aggressive thoughts.
Genetics and evolution: aggressive tendencies have a heritable component. Evolutionary psychologists argue that aggression served adaptive functions (resource competition, mate guarding), though this does not justify it.
Neural influences: the amygdala plays a central role in processing threat and triggering aggressive responses. Damage to prefrontal cortex areas can reduce impulse control and increase aggression.
Hormonal influences: testosterone is correlated with aggression, though the relationship is bidirectional (winning a competition also raises testosterone). The correlation is modest and mediated by social context.
Alcohol and drugs: alcohol reduces inhibition and impairs cognitive processing, increasing the likelihood of aggression in provocative situations.
Frustration-aggression hypothesis (revised): frustration does not always cause aggression, but it creates an emotional readiness (anger) that makes aggression more likely, especially when aggressive cues are present.
Cognitive neoassociation theory (Berkowitz): aversive experiences (frustration, pain, heat, foul odours) trigger negative affect, which automatically primes both fight and flight responses. Whether aggression occurs depends on cognitive appraisal.
Displaced aggression: when the source of frustration is unavailable or too powerful, aggression may be directed at a more accessible target.
Rumination: dwelling on a provocation intensifies angry feelings and increases the likelihood of aggressive retaliation.
Social learning theory (Bandura): aggression is learned through:
Observation: watching others (parents, peers, media figures) behave aggressively.
Imitation: reproducing the observed behaviour.
Reinforcement: aggression that is rewarded (or not punished) is more likely to be repeated.
Bobo doll experiment: children who watched an adult model punch and kick an inflatable doll imitated the aggressive behaviour, especially when the model was rewarded.
Media effects on aggression:
Correlational and experimental evidence links violent media exposure to increased aggressive thoughts, feelings, and behaviour.
The General Aggression Model (Anderson & Bushman) integrates these pathways: violent media affects cognition (hostile thoughts), affect (angry feelings), and arousal, which together influence appraisal and behaviour.
Desensitisation: repeated exposure to media violence reduces emotional and physiological responses to real-world aggression.
Cultivation theory: heavy media consumers overestimate the prevalence of violence in the real world.
Catharsis (venting) does not work; it typically increases arousal and aggressive behaviour.
Effective strategies include: teaching anger management and conflict resolution skills, reducing exposure to aggressive models, punishing aggression consistently and promptly, and promoting empathy.
Social-cognitive interventions that teach children to reinterpret ambiguous situations (reducing hostile attribution bias) show promise.
Debates about violent video games and media regulation draw directly on this research. Anti-bullying programmes in schools use social learning principles (modelling prosocial behaviour, reinforcing non-aggressive conflict resolution). Criminal justice policies around alcohol availability and weapons access are informed by the frustration-aggression and weapons-effect findings.
Students often treat the frustration-aggression hypothesis as an absolute law: frustration always causes aggression. The revised version says frustration creates a readiness for aggression, not a guarantee.
The catharsis hypothesis is intuitively appealing but empirically unsupported. Venting (hitting a punching bag, screaming) tends to increase rather than decrease aggression.
Media violence research shows a consistent but modest effect. Students sometimes overstate ("video games cause violence") or dismiss it entirely ("it has no effect"). The evidence supports an increase in aggression-related outcomes, but media is one factor among many.
Instrumental aggression does not require anger. Students sometimes assume all aggression involves emotional arousal, but instrumental aggression is calculated and goal-directed.
⚠️ Know the distinction between hostile and instrumental aggression with examples. This is a near-certain exam question.
⚠️ Be prepared to explain and evaluate the frustration-aggression hypothesis, including the revision.
⚠️ Bandura's Bobo doll experiment is a classic. Know the design, key conditions, and findings.
⚠️ Understand why catharsis does not reduce aggression, and what does.
⚠️ Be able to outline the General Aggression Model and how it integrates biological, cognitive, and social pathways.
True or false: instrumental aggression is motivated primarily by anger.
Fill in the blank: the ______ effect refers to the finding that the mere presence of a weapon can increase aggressive behaviour.
True or false: research supports the catharsis hypothesis, that venting anger reduces further aggression.
Fill in the blank: Bandura's ______ ______ experiment demonstrated that children learn aggressive behaviour through observation.
True or false: the revised frustration-aggression hypothesis states that frustration creates a readiness for aggression rather than directly causing it.
Answers: 1. False (instrumental aggression is goal-directed, not anger-driven). 2. Weapons. 3. False (venting tends to increase aggression). 4. Bobo doll. 5. True.
Q: Explain how social identity theory accounts for prejudice. Use an example.
A: Social identity theory (Tajfel & Turner) holds that people categorise themselves into groups and derive self-esteem from those group memberships. To maintain positive self-regard, people favour their in-group and may derogate out-groups. For example, a university student may develop negative attitudes toward students at a rival university, not because of any personal conflict, but because disparaging the rival enhances the perceived status of their own university and, by extension, their own identity.
Q: A policy-maker argues that violent video games directly cause real-world violence. Evaluate this claim using the research evidence.
A: The claim overstates the evidence. Research (including meta-analyses by Anderson and others) consistently shows that violent media exposure is associated with increased aggressive thoughts, feelings, and minor aggressive behaviours. However, the effect sizes are modest, and the research does not demonstrate that violent games directly cause serious violent crime. The General Aggression Model treats media as one input among many (personality, situation, arousal) that together influence appraisal and behaviour. It is accurate to say violent media increases aggression-related outcomes, but a direct causal link to real-world violence is an oversimplification.
Q: Describe the conditions under which intergroup contact reduces prejudice, according to Allport's contact hypothesis.
A: Allport identified four conditions: (1) the groups have equal status within the contact situation, (2) they work toward common goals, (3) the contact involves intergroup cooperation rather than competition, and (4) the contact has the support of authorities, laws, or customs. Without these conditions, contact can be neutral or even counterproductive.
Q: Distinguish between the original and revised versions of the frustration-aggression hypothesis.
A: The original hypothesis (Dollard et al., 1939) held that frustration always leads to aggression and that aggression is always caused by frustration. The revised version (Berkowitz) softened this: frustration produces negative affect (anger), which creates a readiness for aggression. Whether aggression occurs depends on additional factors, including the presence of aggressive cues (such as a weapon), prior learning, and the individual's cognitive appraisal of the situation.
Q: What is stereotype threat, and give one strategy for reducing it?
A: Stereotype threat (Steele & Aronson) is the anxiety experienced when a person is aware of a negative stereotype about their group and fears confirming it, which can impair performance on relevant tasks. One effective strategy is self-affirmation: before a test, having participants write about values that are important to them reduces the impact of stereotype threat by bolstering their sense of self-integrity.
Prejudice connects to Chapter 8 (Group Influence): social identity theory and group polarisation explain how in-group bias intensifies in group settings. Aggression connects to Chapter 12 (Helping): the same situational factors that inhibit helping (diffusion of responsibility, deindividuation) can facilitate aggression. Both chapters feed directly into Chapter 13 (Conflict and Peacemaking), where prejudice and aggression are root causes of intergroup conflict, and contact-hypothesis principles underpin peacemaking strategies.
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