Aggression — AQA A-Level Psychology
Test yourself on Aggression with AQA A-Level practice questions.
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Aggression explained
Aggression is explained by neural and hormonal mechanisms.
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The limbic system, chiefly the amygdala, appraises threat and drives reactive responses: Gospic found unfair offers in the Ultimatum Game produced a fast amygdala reaction. Serotonin is inhibitory, maintaining the orbitofrontal brake, so low levels mean impulsive violence; Virkkunen found lower 5-HIAA in violent offenders. Testosterone correlates with aggression in Dolan's offender patients, though levels also rise after winning. Genetic factors include the MAOA gene. Brunner's Dutch family of 14 men shared a complete MAOA deficiency, and Caspi showed the MAOA-L variant predicted antisocial behaviour only in the maltreated.
The ethological explanation of aggression, including reference to innate releasing mechanisms and fixed action patterns. Evolutionary explanations of human aggression.
Ethology studies behaviour in the wild and treats aggression as innate and adaptive. Lorenz argued that fights within a species are ritualistic, ending in appeasement displays, so they settle hierarchy and spread animals over territory without killing. The mechanism has two parts: an innate releasing mechanism is a hard-wired circuit tripped by a specific sign stimulus, and it releases a fixed action pattern, a stereotyped, universal sequence that is ballistic once begun. Tinbergen's sticklebacks attacked any wooden model with a red underside, ignored a realistic one without it, and ran the sequence to completion after the rival was removed. Evolutionary accounts add function: Shackelford found mate-retention tactics predicted violence towards wives, cuckoldry being the ancestral cost.
Social psychological explanations of human aggression, including the frustration-aggression hypothesis, social learning theory as applied to human aggression, and de-individuation.
Three social accounts. Dollard's frustration-aggression hypothesis says a blocked goal creates a drive that must be discharged, often displaced onto a safer target; Geen's participants who were insulted while failing a puzzle gave the strongest shocks. Berkowitz's weapon effect showed cues matter: guns on the table raised the shocks given. Bandura added social learning theory: in 1961, 72 children who watched an adult batter a Bobo doll copied the precise acts. Later, Bandura showed vicarious reinforcement: imitation fell when children saw the model punished. De-individuation is the loss of private self-awareness in a crowd; Zimbardo's hooded women shocked for twice as long as those wearing name tags.
Institutional aggression in the context of prisons: dispositional and situational explanations.
Two rival accounts of why prisons turn violent. The dispositional or importation model, from Irwin and Cressey, says inmates carry street values, gang ties and violent histories in through the gate, so prison concentrates aggression rather than creating it; DeLisi found gang-affiliated young inmates were the ones who offended inside. The situational or deprivation model, from Sykes, blames the regime: the pains of imprisonment, lost liberty, autonomy, goods, intimate relationships and security, plus overcrowding and poor staffing, make aggression a way of regaining control. Steiner's survey of over five hundred prisons found inmate-on-inmate violence tracked situational variables, while Camp and Gaes found near-identical misconduct in randomly allocated security levels.
Media influences on aggression, including the effects of computer games. The role of desensitisation, disinhibition and cognitive priming.
Does watching or playing violence make people aggressive? Experiments say a little: Bartholow and Anderson had students play a violent or a non-violent game and then blast an opponent with noise, and the violent-game group chose louder, longer bursts; Anderson's meta-analysis found a small but consistent effect. Three mechanisms are named. Desensitisation is the loss of physiological arousal, measured as heart rate, after repeated exposure, so violence stops shocking. Disinhibition is media showing aggression as normal and justified, which loosens learned social restraint. Cognitive priming occurs when violent media provides cues that activate existing aggressive thoughts and scripts in memory, explaining a sudden outburst.
Your focus
- Describe the roles of the amygdala and orbitofrontal cortex in reactive aggression, using Gospic's Ultimatum Game.
- Explain why low serotonin releases impulsive violence, using Virkkunen's lower 5-HIAA in violent offenders.
- Explain what the MAOA gene codes for and what the complete MAOA deficiency did in the 14 men of Brunner's Dutch family.
Show all 23 objectives
- Apply Caspi's gene-environment interaction to explain why the MAOA-L variant alone does not predict antisocial behaviour.
- Evaluate biological explanations on reductionism and what determinism would imply for legal responsibility.
- Explain an innate releasing mechanism and a fixed action pattern and how a sign stimulus connects them.
- Describe Tinbergen's stickleback study and the features of a fixed action pattern that it demonstrated.
- Explain why Lorenz argued ritualised aggression and appeasement limit killing within a species.
- Apply anti-cuckoldry logic to Shackelford's link between mate-retention tactics and violence towards wives.
- Evaluate the ritual claim using Goodall's Gombe chimpanzees and Nisbett's culture of honour.
- Explain the frustration-aggression hypothesis through a blocked goal, an aggressive drive and displacement.
- Describe Bandura's Bobo doll findings and how punishing the model changed what children imitated.
- Explain de-individuation as a loss of private self-awareness, using Zimbardo's hooded participants.
- Apply the weapon effect to explain why environmental cues raise aggression beyond frustration alone.
- Evaluate catharsis and the Bobo doll method, given that venting raises later aggression and the doll invites hitting.
- Describe the importation model as values, gang ties and violent history carried in through the gate.
- Explain the deprivation model through Sykes's pains of imprisonment and regime factors such as overcrowding.
- Apply both models to a described prison incident and say which one the evidence there favours.
- Evaluate the two models using Camp and Gaes's random allocation result and the different policy each implies.
- Explain desensitisation, disinhibition and cognitive priming as three distinct routes from media to aggression.
- Describe Bartholow and Anderson's noise blast study and the size of effect Anderson's meta-analysis found.
- Apply cognitive priming to explain why a media effect can be sudden and short-lived after a matching cue.
- Evaluate media effects research, given that noise blasts are not violence and aggressive people choose violent games.
Aggression exam tips
Marking Points
- Limbic system: the amygdala evaluates sensory threat and, with the hypothalamus, drives reactive aggression, while the orbitofrontal cortex normally inhibits it; Gospic's fMRI Ultimatum Game evidence.
- Serotonin: normal levels maintain inhibitory control at the orbitofrontal cortex; low levels remove this brake so impulses go undamped, evidenced by Virkkunen's lower 5-HIAA in impulsive violent offenders.
- Testosterone: an androgen linked to aggression in males, shown by Dolan's correlation in offender patients and by animal castration and reinstatement studies.
- Genetic factors: twin and adoption studies give a substantial heritability estimate; the MAOA gene codes for the enzyme that breaks down serotonin, and a complete MAOA deficiency ran through 14 men in Brunner's Dutch family.
- Evaluation: Caspi's gene-environment interaction, where the MAOA-L variant predicted antisocial behaviour only alongside childhood maltreatment.
- Ethology defined: aggression is innate, adaptive and studied in the natural environment, with Lorenz as the named theorist.
- Ritualised aggression: threat displays and appeasement signals limit killing within a species, and the benefits are territorial spread, dominance hierarchy and the survival of the defeated animal.
- Innate releasing mechanism: a sign stimulus activates a built-in neural network that releases the behaviour.
- Fixed action pattern: stereotyped, universal, ballistic, unaffected by learning and triggered by a specific stimulus, demonstrated by Tinbergen's red-bellied stickleback models.
- Evolutionary explanations: sexual jealousy and anti-cuckoldry, mate-retention tactics such as direct guarding and negative inducements, bullying as an adaptive strategy, and Shackelford's link between retention tactics and wife violence.
- Evaluation: Goodall's Gombe chimpanzees killed systematically despite appeasement signals, contradicting the ritual claim; Nisbett's culture of honour shows learned variation; extrapolating from fish and birds to human aggression is questionable, and evolutionary accounts are criticised as post hoc and gender-biased.
- Frustration-aggression: a blocked goal produces frustration, frustration produces an aggressive drive, and discharging it is said to be cathartic, with displacement onto an available target.
- Supporting evidence: Geen's insulted condition gave the strongest shocks, and Berkowitz and LePage's weapon effect showed environmental cues increase aggression. Berkowitz later reformulated the hypothesis so that any negative affect can provoke aggression.
- Social learning theory: observation of a model, vicarious reinforcement, the four mediational processes and self-efficacy, evidenced by imitation of specific acts in Bandura's 1961 Bobo doll study and his 1965 punished-model study.
- De-individuation: anonymity and crowd membership reduce private self-awareness and accountability, shifting behaviour towards local group norms, as in Zimbardo's hooded participants.
- Evaluation: catharsis is unsupported because venting raises later aggression; the Bobo doll is an inflatable toy made to be hit, inviting demand characteristics and telling us little about real violence; de-individuation can be prosocial, since Johnson and Downing's nurse uniforms reduced shocks while hooded costumes increased them.
- Definition: institutional aggression is violence occurring within an organised setting such as a prison, between inmates or directed at staff.
- Dispositional explanation, the importation model: characteristics brought in by the inmate, including age, gang membership, prior violence and anti-authority values, with DeLisi's gang-affiliated young offenders as evidence.
- Situational explanation, the deprivation model: Sykes's pains of imprisonment plus regime factors such as overcrowding, heat and staffing, with Steiner's prison-level situational predictors as evidence.
- Weighing the two: Camp and Gaes randomly allocated inmates across security levels and found similar rates of misconduct, which favours importation over the regime.
- Evaluation: the models are not mutually exclusive and an interactionist account fits the data better; each yields a different policy, gang-aware allocation against reducing overcrowding; much of the evidence is correlational and drawn from male American prisons, which limits generalisation.
- What each type of evidence can show: experiments such as Bartholow and Anderson's noise blasts establish causation but measure proxies, correlations such as DeLisi's juvenile offenders cannot establish it, and longitudinal cohort studies track real outcomes over years.
- Desensitisation: repeated exposure lowers physiological arousal to violence and reduces sympathy for victims, as in Weisz and Earls's mock trial.
- Disinhibition: media presents aggression as normative, justified and free of consequence, weakening the social norms that usually restrain it.
- Cognitive priming: violent media provides cues that activate existing aggressive thoughts and scripts in memory, which is why the effect can be immediate and short-lived.
- Evaluation: laboratory measures such as noise blasts and hot sauce are not violence; the causal direction is unclear because aggressive people choose violent games; Ferguson argues effect sizes are small and shrink once family violence and mental health are controlled; the research is socially sensitive because it shapes censorship policy.
Examiner Tips
- 💡If the stem gives someone a violent family history, use it: name heritability or the MAOA gene, then state that an environmental trigger such as maltreatment is required.
- 💡When evaluating biological explanations, ensure you move beyond description; use diathesis-stress, animal extrapolation and determinism to build a robust discussion.
- 💡Name the researcher, the sample and the finding: Brunner studied 14 men in one Dutch family with a complete MAOA deficiency.
- 💡Use both technical terms accurately in the opening sentences of an explain answer, each tied to one animal example, because precise use of the terminology is what the knowledge marks are for.
- 💡Evaluate evolutionary explanations with a named cultural counter-case such as Nisbett rather than the vague claim that they ignore nurture.
- 💡Ethological and evolutionary are separate bullets in the specification; answer the one the question names, because content on the other earns nothing.
- 💡Scenario questions point to one explanation: a crowd in masks vandalising property is de-individuation, a child copying an admired older sibling is social learning; name it, then quote the scenario's own detail as you apply it.
- 💡In a sixteen-mark answer, use the three explanations against each other, for example that social learning explains why aggression is selective and situation-specific while a frustration drive cannot.
- 💡Evaluation scores better when it names the counter-study, such as Johnson and Downing, than when it says the research is mixed.
- 💡The stem gives the steer: a prisoner with gang tattoos and a violent record is dispositional, a newly overcrowded wing with staff shortages is situational; quote the detail as you name the model.
- 💡Discuss expects both explanations, so keep the description tight and spend the remaining marks comparing how well each predicts who becomes violent.
- 💡Finish by stating which model the evidence favours and why, rather than concluding weakly that both play a part.
- 💡Match the mechanism to the scenario: an immediate reaction after playing suggests priming or disinhibition, while a person unmoved by real violence suggests desensitisation.
- 💡Name the method as you cite the study, for example in a meta-analysis of published experiments, because the methodological comment is where the evaluation marks are.
- 💡Build the evaluation around what each method can and cannot establish rather than listing generic criticisms about ecological validity.
Common Mistakes
- Saying testosterone causes aggression when the evidence is correlational, and ignoring that the causal arrow can run backwards because winning a contest raises testosterone.
- Calling serotonin the aggression chemical; it is inhibitory, so it is low serotonin that is associated with violence.
- Treating the MAOA gene as a direct gene for aggression and leaving out Caspi's finding that maltreatment was needed for the MAOA-L variant's effect to appear.
- Naming brain structures without saying what each does, or muddling the limbic system with the frontal cortex that restrains it.
- Blurring the two technical terms: the innate releasing mechanism is the trigger circuit, the fixed action pattern is the behaviour it releases.
- Describing Tinbergen's study as being about colour preference rather than about a sign stimulus releasing a stereotyped sequence.
- Forgetting that a fixed action pattern is ballistic, so it continues after the stimulus disappears; that detail is often the discriminating mark.
- Writing as though evolutionary explanations justify aggression or make it inevitable, when they describe adaptive function only.
- Stating that frustration always leads to aggression as though it were fact; the absolute claim is what the evidence refused, which is why Berkowitz reformulated it as negative affect.
- Defining de-individuation as simply being in a crowd, when the explanation requires anonymity and reduced private self-awareness.
- Saying the Bobo doll children became violent, rather than that they imitated specific modelled acts towards a toy.
- Presenting catharsis as a research finding when it is a claim of the hypothesis that later work contradicts.
- Swapping the labels: importation is the dispositional explanation and deprivation is the situational one, and reversing them costs the whole answer.
- Listing the pains of imprisonment without explaining why deprivation should produce aggression, namely as a coping response that restores some control.
- Leaning on Zimbardo's Stanford prison simulation as though it were evidence from a real prison, without noting the student volunteers and the demand characteristics.
- Describing prison violence in general terms instead of attaching each study to one named model.
- Treating desensitisation, disinhibition and priming as three names for one idea: the first is reduced arousal, the second is changed norms, the third is memory activation.
- Reading a correlation between hours of violent gaming and aggression as proof that gaming caused it.
- Claiming media violence causes real-world atrocities such as shootings, which no study shows and which examiners read as uncritical.
- Ignoring the timescale: desensitisation builds over long exposure while priming is immediate and cue-driven, so an outburst straight after play is priming.