Component 2 — The 20 Core Studies (AS & A-Level)

Milgram (1963) - Social

Aim: Investigate obedience to an authority figure giving destructive orders. Sample: 40 males (20-50 yrs) via volunteer sample. Method: Lab experiment / controlled observation at Yale. Procedure: Participants ordered to shock a 'learner' up to 450V for wrong answers. Findings: 100% went to 300V; 65% (26/40) went to maximum 450V. Conclusion: Situational factors exert powerful influence over behavior, causing individuals to enter an agentic state.

Bocchiaro et al. (2012) - Social

Aim: Measure rates of obedience, disobedience, and whistleblowing. Sample: 149 Dutch university students. Method: Controlled lab scenario. Procedure: Participants asked to write a persuasive letter encouraging friends to enter a sensory deprivation study. Findings: 76.5% obeyed, 14.1% disobeyed, 9.4% blew the whistle (only 3.6% actually blew whistle open-form). Conclusion: People vastly overestimate their likelihood to disobey or blow the whistle compared to actual behavior.

Piliavin et al. (1969) - Social

Aim: Investigate bystander behavior on NY subway under varying conditions (Ill vs Drunk, Black vs White victim, Model intervention). Sample: ~4450 subway commuters. Method: Field experiment. Findings: Ill victim helped 95% of time; Drunk victim helped 50% of time. Help was spontaneous, no evidence of diffusion of responsibility. Conclusion: Cost-reward model explains helping; immediate physical presence in enclosed space increases responsibility.

Levine et al. (2001) - Social

Aim: Cross-cultural study investigating non-emergency helping behavior in 23 international cities. Sample: 1,198 individuals. Method: Field experiment (pen dropped, leg-brace struggle, blind crossing street). Findings: Highest helping in Simpatia cultures (Rio 93%, San Jose 90%); lowest in fast-paced industrialized economies (Kuala Lumpur 40%, NY 53%). Conclusion: Cultural values (Simpatia) and economic pace predict altruism.

Loftus & Palmer (1974) - Cognitive

Aim: Investigate effect of leading questions on eyewitness recall. Sample: Exp 1 (45 students), Exp 2 (150 students). Method: Lab experiment. Findings: Exp 1 speed estimates: "Smashed" = 40.5 mph vs "Contacted" = 31.8 mph. Exp 2: "Smashed" group had significantly more false recollections of broken glass (32%) vs "Hit" (14%). Conclusion: Post-event information distorts schema and alters underlying memory reconstruction.

Grant et al. (1998) - Cognitive

Aim: Test context-dependent memory in environmental learning (Silent vs Noisy). Sample: 39 students. Method: Lab experiment, independent measures. Procedure: Study text in noisy/silent environment, test recall in matching/mismatched context. Findings: Performance significantly better when study and test environments matched (e.g., Silent-Silent or Noisy-Noisy). Conclusion: Contextual cues during encoding enhance retrieval performance.

Moray (1959) - Cognitive

Aim: Investigate selective auditory attention in dichotic listening. Sample: University students/researchers. Method: Lab experiment. Procedure: Shadowing message in one ear while unattended ear received words/instructions. Findings: Unattended words were not recalled (cocktail party effect); however, hearing own name in unattended ear broke through barrier 33% of the time. Conclusion: Unattended messages are blocked before conscious processing unless personally meaningful.

Simons & Chabris (1999) - Cognitive

Aim: Investigate inattentional blindness in dynamic visual scenes. Sample: 228 undergraduate participants. Method: Lab experiment. Procedure: Watch video of basketball players; count passes; unexpected event occurs (Gorilla or Woman with Umbrella). Findings: 46% failed to notice the unexpected event. Gorilla noticed more when tracking Black shirt team (58%) vs White shirt team (27%). Conclusion: Visual attention is highly selective; unattended events are missed.

Bandura et al. (1961) - Developmental

Aim: Test Social Learning Theory via imitation of adult aggression. Sample: 72 nursery children (mean age 52 mos). Method: Lab experiment, matched pairs. Procedure: Exposed to aggressive or non-aggressive adult model; subjected to mild aggression arousal; observed for 20 mins. Findings: Children exposed to aggressive model showed significantly more imitative physical/verbal aggression. Boys imitated male model more. Conclusion: Aggressive behavior is acquired through observational learning.

Chaney et al. (2004) - Developmental

Aim: Test operant conditioning using a 'Funhaler' to increase adherence to asthma medication in children. Sample: 32 Australian children (1.5–6 yrs). Method: Field experiment / repeated measures. Procedure: Standard inhaler replaced with Funhaler (whistle/spinner incentive) for 2 weeks. Findings: 81% parent compliance with Funhaler vs 59% with existing inhaler; children took recommended doses significantly more. Conclusion: Positive reinforcement improves medical compliance in young children.

Kohlberg (1968) - Developmental

Aim: Investigate moral reasoning development across 12-year longitudinal span. Sample: 75 American boys (aged 10-16 at start, tracked to 22-28). Method: Longitudinal study / scenario interview. Procedure: Presented hypothetical moral dilemmas (e.g., Heinz dilemma). Findings: 3 levels (Pre-conventional, Conventional, Post-conventional) broken into 6 invariant stages. Progress is sequential regardless of culture. Conclusion: Moral reasoning develops through invariant, universal stages.

Lee et al. (1997) - Developmental

Aim: Compare Chinese and Canadian children's moral evaluations of lie-telling and truth-telling in prosocial and antisocial settings. Sample: 120 Chinese, 108 Canadian children (aged 7, 9, 11). Method: Cross-cultural quasi-experiment. Findings: Chinese children rated truth-telling about prosocial deeds less positively and lie-telling more positively (modesty bias) than Canadian children. Conclusion: Cultural values directly shape moral evaluations of lying/truthfulness.

Sperry (1968) - Biological

Aim: Examine functional specialization of hemisphere domains in split-brain patients. Sample: 11 commissurotomy patients. Method: Quasi-experiment / lab task. Procedure: Visual stimuli tachistoscopically flashed to RVF (left hemisphere) or LVF (right hemisphere). Findings: Visual info shown to RVF could be named verbally; info shown to LVF could not be named but could be pointed to with left hand. Conclusion: Left hemisphere controls speech/language; right controls spatial/tactile processing.

Casey et al. (2011) - Biological

Aim: Track impulse control (delay of gratification) over 40 years using fMRI scanning. Sample: 59 participants tracked from 4 years old into 40s. Method: Quasi / Longitudinal study with fMRI. Findings: Low delayers made more errors on 'go/no-go' tasks with emotional faces. fMRI showed high delayers had greater Ventral Striatum activity (reward) in low delayers, and greater Inferior Frontal Gyrus activity in high delayers. Conclusion: Delay of gratification is a stable trait underpinned by prefrontal-striatal circuits.

Blakemore & Cooper (1970) - Biological

Aim: Examine physiological and behavioral effects of restricted early visual environment on kitten visual cortex. Sample: Kittens raised from birth in dark, then strictly vertical or horizontal stripe cylinders. Method: Lab experiment. Findings: Kittens raised in vertical lines were blind to horizontal contours and lacked horizontal orientation detector neurons in visual cortex (and vice versa). Conclusion: Brain plasticity adapts neural structure based on early visual experience.

Maguire et al. (2000) - Biological

Aim: Investigate structural brain changes (hippocampal volume) in Licensed London Taxi Drivers. Sample: 16 male right-handed taxi drivers vs 50 male controls. Method: Quasi-experiment using MRI scans. Findings: Taxi drivers had significantly increased posterior hippocampal volume and decreased anterior volume. Volume correlated positively with time spent driving. Conclusion: Hippocampus displays structural plastic changes in response to environmental spatial demands.

Freud (1909) - Individual Differences

Aim: Document psychoanalytic treatment of a 5-year-old boy's phobia of horses (Little Hans). Sample: Single case study (Little Hans). Method: Case study (father reported observations to Freud). Findings: Horse phobia represented displaced anxiety/fear of father due to Oedipus Complex (winger/black muzzle = father's glasses/mustache). Resolution occurred when Oedipus complex resolved. Conclusion: Supports psychodynamic theories of infantile sexuality, repression, and unconscious phobia displacement.

Baron-Cohen et al. (1997) - Individual Differences

Aim: Test whether adults with Autism/Asperger's (AS) lack Theory of Mind using the 'Eyes Test'. Sample: 16 AS adults, 50 Normal adults, 10 Tourette Syndrome adults. Method: Quasi-experiment. Findings: AS group performed significantly worse (mean 16.3/25) on identifying emotions in photos of eyes compared to controls (mean 20.3/25). Males scored lower than females. Conclusion: Core deficit in Autism/AS is impaired Theory of Mind regardless of intelligence.

Gould / Yerkes (1982) - Individual Differences

Aim: Critique Yerkes' WW1 US Army IQ testing (Alpha/Beta/Individual examinations). Method: Review article / Historical critique. Findings: Cultural bias heavily systematically penalized Black participants and recent immigrants (unlettered, unfamiliar with US culture). Lead to false claims of innate racial intelligence hierarchies and Eugenics legislation. Conclusion: Psychometric intelligence tests reflect cultural familiarity rather than innate intelligence.

Hancock et al. (2011) - Individual Differences

Aim: Analyze language characteristics of psychopathic murderers using text analysis (Wmatrix/DAL). Sample: 14 psychopathic murderers vs 38 non-psychopathic murderers. Method: Quasi / Psycholinguistic analysis. Findings: Psychopaths used significantly more cause-and-effect conjunctions (because, since), 2x more food/money/basic need words, fewer social/family words, and more past-tense verbs. Conclusion: Psychopaths exhibit selfish, emotionally detached, instrumental language patterns.