Essay Structure — Paper 2
Two essays from your chosen option. Each worth 22 marks.
📌 Paper 2 Overview
Paper 2 is your option topic. You study one option (Abnormal, Developmental, Health, or Relationships) and answer two essay questions from that option. Each question is worth 22 marks. The essay structure is the same ATPP format from Paper 1, but with deeper evaluation expected.
Introduction
Define the key term(s) directly from the question. State your argument clearly. Name the study/studies you will use and how they are relevant.
Body 1 (always)
ATPP: Aim → Type → Procedure → Participants. Connect findings directly to the question prompt. Don't summarize — analyze.
Body 2 (22-mark Qs)
Second study using ATPP. Paper 2 Qs almost always require two studies. Compare and contrast findings between the two studies where possible.
Conclusion
Results → Strength → Weakness → Validity/Generalizability → Ethical consideration → Link back to prompt. Offer a balanced verdict on what the evidence shows.
💡 Paper 2 Exam Tips
22-mark questions almost always need two studies. Never go in with only one study prepared per topic.Plan: 1 intro + 2 ATPP bodies + 1 conclusion
Paper 1 studies carry over. Caspi (2003), Kendler (2006), Newcomer (1999), Wedekind (1995), Drury (2009), and Hilliard & Liben (2010) all answer Paper 2 questions.Look for ⭐ P1 badge on study cards
Define the disorder or concept first. For Abnormal questions especially — always define the condition (e.g., depression) before explaining its etiology.
Evaluation keywords matter. Use: "However…", "This is supported by…", "A limitation is…", "This suggests that…" — examiners reward analytical language.
Ethics in conclusion. Every study has an ethical dimension — mention deception, debriefing, harm to participants, or animal welfare.1–2 sentences is enough
Generalizability check. Ask: WEIRD sample? (Western, Educated, Industrial, Rich, Democratic). Small N? Lab vs. real world? Answer this in every conclusion.
Abnormal Psychology
Diagnosis validity & reliability · Etiology (Bio/Cog/Soc) · Treatment
🧩 Background: Factors Influencing Diagnosis
Validity of a diagnosis means it actually measures what it claims to measure — that the label reflects a genuine, distinct condition. Reliability means different clinicians, given the same patient, will reach the same diagnosis.
Diagnosis is influenced by cultural bias (cultural norms determine what is "normal"), clinical bias (the clinician's own background and expectations), and the subjective nature of psychiatric criteria (DSM relies on self-reported symptoms). Rosenhan (1973) challenged both validity and reliability of the system itself. Li-Repac (1980) demonstrated how the clinician's ethnicity biases judgment.
🧬 Background: Etiology of Disorders (Depression as the model disorder)
Biological: Depression has a genetic component (twin studies show ~38% concordance in MZ twins — Kendler 2006). The serotonin transporter gene (5-HTTLPR) interacts with environmental stress to trigger depression (Caspi 2003). Cognitive: Beck's Cognitive Triad (1967) proposes negative schemas about self, world, and future cause depression. Cognitive biases (negative attentional bias) maintain the disorder. Sociocultural: Brown & Harris found that social factors — particularly the lack of an intimate relationship and stressful life events — are major vulnerability factors for depression in women.
💊 Background: Treatment
Biological treatment: Antidepressants (SSRIs, tricyclics) target serotonin reuptake. Fournier et al's meta-analysis found these are significantly more effective than placebo only for severe depression — raising questions about over-prescription. Psychological treatment: Cognitive Behavioral Therapy (CBT) targets negative automatic thoughts and dysfunctional core beliefs. Jacobson et al found that the behavioral activation component of CBT alone may be as effective as the full cognitive package. Cultural treatment: Griner & Smith's meta-analysis showed culturally adapted psychotherapy is substantially more effective for minority clients than standard therapy.
🔴 Diagnosis — Key Studies
Rosenhan
1973 · "On Being Sane in Insane Places"
⭐
AimTo test whether psychiatric hospitals could distinguish sane from insane individuals
TypeField experiment (covert participant observation)
Pts8 pseudopatients (including Rosenhan himself) presented at 12 different US psychiatric hospitals
ProcedurePseudopatients reported hearing voices saying "empty," "hollow," and "thud" — words chosen because they had no clinical history in psychiatric literature. Once admitted, they behaved completely normally and took notes openly.
ResultsAll 8 were admitted; 7 diagnosed with schizophrenia, 1 with manic-depressive psychosis. Staff never detected them (though real patients often did). Average stay was 19 days (range: 7–52 days). All were discharged with a diagnosis "in remission." In a follow-up, a hospital told pseudopatients would be sent identified 41 of 193 real patients as impostors — none were actually sent.
Memory Hook"Sane in insane places." Once labeled schizophrenic, normal behavior is re-read as symptoms. Labels stick.
✅ StrengthHigh ecological validity — real hospitals, real consequences for "patients"
❌ WeaknessDeception raises serious ethical concerns; cannot replicate today; hospitals have since improved
Li-Repac
1980 · Cultural Bias in Clinical Diagnosis
⭐
AimTo investigate whether a clinician's cultural background influences their diagnostic judgments
TypeLaboratory experiment using clinical case materials
PtsWhite American and Chinese-American therapists rating Chinese and White patients
ProcedureTherapists reviewed case files and interviews of both Chinese and White patients and rated patients on various clinical dimensions (depression, anxiety, social adjustment, overall pathology)
ResultsWhite therapists rated Chinese patients as significantly more depressed, inhibited, and less socially skilled than Chinese-American therapists rated the same patients. Shows clinician's cultural background affects diagnosis.
Memory Hook"Who's doing the diagnosing matters as much as who's being diagnosed." Cultural lens = diagnostic bias.
✅ StrengthControlled design isolating cultural background of clinician as the variable
❌ WeaknessSmall, specific sample; artificial rating of case files ≠ real clinical encounters
🧬 Biological Etiology — Key Studies
Kendler et al
2006 · Swedish Twin Registry · Depression & Genetics
⭐
AimTo assess the genetic contribution to major depression using twin concordance data
TypeLongitudinal twin study using concordance rates
Pts~42,000 twin pairs from the Swedish Twin Registry
ProcedureCompared concordance rates for major depression in monozygotic (MZ — 100% shared DNA) and dizygotic (DZ — ~50% shared DNA) twins over time
ResultsMZ twins showed ~38% concordance for depression; DZ twins showed ~26%. Higher concordance in MZ twins indicates a genetic component. Concordance never reaches 100%, confirming that environment also plays a significant role.
📚 Originally studied in Paper 1 (Biological Approach — Genetics)
Memory Hook"Identical twins, more identical risk." Genetics matters but doesn't determine destiny.
✅ StrengthEnormous sample (~42k pairs); elegantly controls shared environment by comparing MZ vs DZ
❌ WeaknessMZ twins may share more similar environments too; concordance never 100% — genetics alone insufficient
Caspi et al
2003 · 5-HTTLPR Gene & Life Stress · Dunedin Cohort
⭐
AimTo test whether the 5-HTTLPR serotonin transporter gene moderates the effect of stressful life events on depression
TypeLongitudinal prospective study (birth to age 26)
Pts1,037 individuals from the Dunedin Multidisciplinary Health and Development Study in New Zealand
ProcedureParticipants genotyped for 5-HTTLPR allele variants (short "s" / long "l"). Stressful life events recorded between ages 21–26. Depression assessed at age 26 using diagnostic interviews.
ResultsIndividuals with one or two short (s) alleles who experienced stressful life events had significantly higher rates of depression and suicidality than those with long (l) alleles who experienced the same stress. The gene alone, without stress, did not predict depression.
📚 Originally studied in Paper 1 (Biological Approach — Genetics)
Memory Hook"Genes load the gun; stress pulls the trigger." The s/s genotype is a vulnerability, not a sentence.
✅ StrengthLongitudinal from birth eliminates recall bias; large cohort; tracked real-world stress events
❌ WeaknessNew Zealand cohort (WEIRD); some replication attempts have produced mixed results; correlational
🧠 Cognitive Etiology — Key Study
Beck's Cognitive Model of Depression (1967) — Essential Theory
Beck proposed that depression is caused by systematic errors in thinking, organized around three themes — the Cognitive Triad:
- Negative view of self ("I am worthless and inadequate")
- Negative view of the world ("Everything is hopeless and demanding")
- Negative view of the future ("Nothing will ever improve")
These produce cognitive distortions (e.g., catastrophizing, overgeneralization) that reinforce depressive schemas. Beck's model is the theoretical foundation for Cognitive Behavioral Therapy (CBT).
Caseras et al
2007 · Attentional Bias & Dysphoria
AimTo test Beck's prediction that dysphoric individuals show an attentional bias toward negative stimuli
TypeLab experiment using eye-tracking methodology
PtsParticipants categorized as dysphoric (subclinical depression, high dysfunctional attitudes score) vs. non-dysphoric controls
ProcedureParticipants viewed pairs of emotionally valenced images (positive, negative, neutral) on a screen while eye movements were tracked. Patterns of attention allocation were recorded and compared between groups.
ResultsDysphoric participants showed significantly greater attentional bias toward negative stimuli compared to non-dysphoric participants. This pattern supports Beck's cognitive model — depressed individuals selectively attend to negative information, which maintains and deepens their negative thinking patterns.
Memory Hook"Sad brains seek sad things." Negative attention bias = a cognitive feedback loop that keeps depression going.
✅ StrengthEye-tracking is an objective, implicit measure that avoids self-report bias
❌ WeaknessDysphoria ≠ clinical depression; lab attention tasks may not reflect real-world thinking patterns
🌍 Sociocultural Etiology & Treatment — Key Studies
Brown & Harris
1978 · Social Origins of Depression · London Women
⭐
AimTo investigate the social and environmental factors that contribute to clinical depression in women
TypeSurvey / structured clinical interview; correlational design
Pts458 working-class women living in Camberwell, South London
ProcedureWomen were assessed for depression via interview. Researchers identified "provoking agents" (severe life events) and "vulnerability factors." Vulnerability factors included: (1) loss of mother before age 11, (2) three or more children under 14 at home, (3) absence of a close, confiding relationship (especially a partner), (4) lack of employment outside the home.
ResultsWomen who experienced a severe life event AND had one or more vulnerability factors were significantly more likely to develop depression. Lack of a close confiding relationship was the strongest vulnerability factor. Social isolation and lack of support are powerful etiological factors.
Memory Hook"No confidant + a hard life = depression." Social support is a protective buffer against depression.
✅ StrengthIdentifies specific, measurable social risk factors; large community sample (not just clinical patients)
❌ WeaknessAll-female, working-class, British sample — poor generalizability; retrospective; correlation not causation
Griner & Smith
2006 · Culturally Adapted Therapy · Meta-Analysis
AimTo determine whether culturally adapted psychotherapy is more effective than standard therapy for minority clients
TypeMeta-analysis of 76 published studies
PtsStudies included predominantly ethnic minority clients in the United States
ProcedureReviewed 76 studies comparing culturally adapted interventions (e.g., therapy delivered in the client's native language, incorporating cultural values/practices) against standard unadapted treatments. Calculated overall effect size.
ResultsCulturally adapted interventions had a moderate and positive effect size (d ≈ 0.45) over standard treatments. Interventions delivered in the client's first language were particularly effective. Group-based culturally adapted interventions outperformed individual-based ones.
Memory Hook"Therapy in your language, in your culture, works better." One-size-fits-all treatment doesn't fit all.
✅ StrengthMeta-analysis aggregates many studies — high statistical power; directly addresses a gap in treatment effectiveness
❌ WeaknessPublication bias (positive results over-represented); varies widely by disorder type and culture studied
Fournier et al
2010 · Antidepressant Efficacy by Severity
AimTo test whether antidepressant efficacy varies based on initial severity of depression
TypeMeta-analysis using individual patient data from randomized controlled trials
PtsData from 6 RCTs comparing antidepressants (imipramine or paroxetine) to placebo
ProcedureAnalyzed individual patient data from RCTs across different severity levels of depression (mild, moderate, severe, very severe — as measured by Hamilton Depression Rating Scale). Compared drug vs. placebo outcomes at each severity level.
ResultsAntidepressants provided minimal clinical benefit over placebo for mild to moderate depression (the drug–placebo difference was small and clinically insignificant). For severe and very severe depression, antidepressants showed a substantial, clinically meaningful advantage over placebo.
Memory Hook"Pills help the severely depressed, barely help the mildly depressed." Severity of illness determines drug effectiveness.
✅ StrengthUses individual patient data from RCTs — highest-quality evidence; examines severity as a variable
❌ WeaknessOnly two specific antidepressants studied; publication bias in original RCTs; short-term outcomes only
Developmental Psychology
Attachment · Gender development · Cognitive development · Socialization
🧩 Background: Attachment Theory
John Bowlby proposed that attachment is an innate, evolved mechanism ensuring infant survival. He argued for a critical period (roughly birth to 2–3 years) during which an infant must form an attachment to a caregiver (usually the mother — "monotropy"). Failure to form this bond leads to maternal deprivation, with long-term consequences for emotional, cognitive, and social development.
Mary Ainsworth extended Bowlby's theory by identifying distinct attachment types — Secure (B), Insecure Avoidant (A), and Insecure Resistant/Ambivalent (C) — using the standardized Strange Situation procedure. The quality of attachment depends on caregiver sensitivity to infant signals.
⚥ Background: Gender Development
Social Learning Theory (Bandura) explains gender development through observation of same-sex models, reinforcement of gender-appropriate behavior, and punishment or discouragement of gender-inappropriate behavior. Children learn gender roles by watching and imitating parents, peers, and media.
Gender Schema Theory (Bem, 1981) adds a cognitive component: children actively construct schemas (mental frameworks) about what is "for boys" and "for girls," and then use these schemas to filter and organize new information. Once a gender schema is established, children seek out and remember schema-consistent information.
Research by Fagot (1978) shows parental reinforcement shapes early gender-typed behavior. Hilliard & Liben (2010) demonstrate that even brief classroom emphasis on gender categories accelerates stereotype development in young children.
🟡 Attachment — Key Studies
Ainsworth et al
1970/1978 · Strange Situation · Attachment Types
⭐
AimTo investigate individual differences in infant attachment and classify distinct attachment patterns
TypeControlled observation in a laboratory setting
Pts26 middle-class American mother–infant pairs; infants aged 12–18 months
ProcedureEight standardized 3-minute episodes in a laboratory playroom: (1) mother and infant alone, (2) stranger enters and interacts, (3) mother leaves infant with stranger, (4) mother returns (first reunion), (5) infant left alone, (6) stranger returns, (7) mother returns (second reunion). Infant behavior during separation and reunion was coded by trained observers.
ResultsThree attachment types identified: Type B — Secure (66%): distressed at separation, warmly greeted mother at reunion, used her as a safe base. Type A — Insecure Avoidant (22%): little distress at separation, avoided/ignored mother at reunion. Type C — Insecure Resistant/Ambivalent (12%): very distressed at separation, angry or clingy/resistant at reunion. Sensitive caregiving predicted secure attachment.
Memory Hook"A = Avoids, B = Best (Secure), C = Clingy." The reunion behavior reveals the attachment — not the separation.
✅ StrengthStandardized, replicable procedure; produced a widely-used and replicated classification system
❌ WeaknessLaboratory is artificial and stressful; original sample was exclusively American, middle-class; Ainsworth had pre-existing relationships with mothers (observer bias)
Bowlby
1944 · 44 Juvenile Thieves · Maternal Deprivation
AimTo test whether early maternal deprivation causes delinquency and emotional maladjustment in children
TypeCase study / retrospective clinical interview
Pts44 juvenile thieves and 44 non-delinquent controls matched for age and IQ, all referred to a child guidance clinic in London
ProcedureBowlby personally interviewed the children and their mothers about early life history, particularly any prolonged separations from the primary caregiver. Children were assessed for "affectionless psychopathy" — an inability to show care or concern for others.
Results14 of the 44 thieves were classified as affectionless psychopaths. Of these 14, 12 had experienced prolonged early separation from their mothers — compared to only 2 in the non-delinquent control group. Bowlby concluded that early maternal deprivation damages the capacity for affection and leads to antisocial behavior.
Memory Hook"No mother bond = no empathy." 12 out of 14 affectionless thieves had lost their mother figure early.
✅ StrengthOne of the first empirical studies linking early experience to later behavior; directly influenced social policy on child care
❌ WeaknessBowlby conducted the interviews himself — serious experimenter bias; retrospective accounts are unreliable; ignores other causes of delinquency (poverty, abuse); correlation ≠ causation
⚥ Gender Development — Key Studies
Fagot
1978 · Parental Reinforcement of Gender · Naturalistic Observation
AimTo investigate whether parents differentially reinforce gender-typed behavior in toddlers
TypeNaturalistic observation in the family home
Pts24 toddlers (aged 20–24 months) and their parents, observed in their own homes
ProcedureResearchers visited each family's home and observed parent–child interactions. They recorded how parents responded to 46 different categories of child behavior, coding reactions as positive (praise, encouragement), negative (criticism, discouragement), or neutral. Child behavior was also coded for gender-appropriateness based on cultural norms.
ResultsParents consistently rewarded gender-appropriate behavior (boys praised for playing with blocks and trucks; girls praised for doll play and requesting help) and discouraged gender-inappropriate behavior. Children who received the most differential reinforcement showed the most strongly gender-typed behavior at follow-up. Both mothers and fathers shaped gender behavior, though patterns differed slightly.
Memory Hook"Parents build gender roles one praise at a time." Reinforcement at 20 months shapes gendered behavior by 12 months later.
✅ StrengthNaturalistic setting — high ecological validity; observational method avoids demand characteristics in toddlers
❌ WeaknessSmall sample (24 families); observer presence may alter parent behavior (reactivity); specific to one cultural context
Hilliard & Liben
2010 · Gender Labeling in Kindergarten
⭐
AimTo test whether a teacher's emphasis on gender categories accelerates gender stereotyping and in-group bias in young children
TypeField experiment with two conditions
Pts~60 kindergarten-aged children (USA) across two classrooms
ProcedureIn the experimental classroom, the teacher consistently used gender labels ("Good morning, boys and girls"), organized activities by gender, and marked gender distinctions throughout the school day for 2 weeks. The control classroom received no gender emphasis. Children were assessed before and after on gender stereotyping and in-group preference.
ResultsAfter 2 weeks, children in the gender-emphasis condition showed significantly stronger gender stereotyping, stronger preference for same-gender peers, and poorer recall of cross-gender peers. The control group showed no significant change. A brief reduction in gender emphasis reversed the effect.
📚 Originally studied in Paper 1 (Sociocultural — Enculturation, Stereotypes, SIT)
Memory Hook"Label the group, create the bias." Two weeks of gender-labeling is enough to sharpen stereotyping in 5-year-olds.
✅ StrengthField experiment — high ecological validity; reversibility of effect is an important finding
❌ WeaknessSmall sample; ethical concern about deliberately inducing stereotypes in young children; limited to US school context
Health Psychology
Health beliefs · Risk & protective factors · Biopsychosocial model · Health promotion
🧩 Background: The Health Belief Model (HBM)
Developed by Rosenstock (1966/1977), the HBM predicts whether a person will engage in health-protecting behavior based on their cognitive appraisal of a health threat. The model has six components:
1. Perceived Susceptibility — "How likely am I to get this disease?" · 2. Perceived Severity — "How serious would it be?" · 3. Perceived Benefits — "Will the action actually help?" · 4. Perceived Barriers — "What makes it hard to do?" · 5. Cues to Action — Internal (a symptom) or external (a health campaign) trigger · 6. Self-Efficacy (added later) — "Do I believe I can do it?"
The HBM is widely used in health campaigns (e.g., vaccination uptake, smoking cessation, sun protection). Research by Deshpande et al (2009) found that perceived barriers are often the strongest predictor of whether people fail to protect their health.
⚖️ Background: Biopsychosocial Model (BPS)
The Biopsychosocial Model (Engel, 1977) replaced the purely biomedical model by arguing that health and illness are determined by the interaction of biological (genetics, physiology), psychological (cognitions, emotions, behavior), and social (culture, relationships, socioeconomic status) factors. No single factor is sufficient to explain health outcomes. This model underpins modern health psychology — for example, obesity is not just about calories (biological) but also about stress eating (psychological) and access to healthy food (social).
📊 Background: Prevalence & Risk Factors — Obesity
Obesity is defined as a BMI ≥ 30. Since 1980, global obesity rates have more than doubled (Hruby & Hu, 2015). Risk factors are biopsychosocial: biological (genetics, metabolism), behavioral (physical inactivity, poor diet), and social/environmental (sedentary screen time, food environment, socioeconomic deprivation). Padez et al (2005) found in Portuguese children that watching TV ≥ 2 hours per day was a significant independent risk factor for obesity, even when diet was controlled. Physical activity functions as a protective factor.
🟢 Health Beliefs — Key Studies
Deshpande, Basil & Basil
2009 · HBM & Sun Safety Behaviours
AimTo test which components of the Health Belief Model best predict sun-protective behavior in university students
TypeCorrelational survey study
Pts199 university students in Canada
ProcedureParticipants completed a questionnaire measuring all HBM constructs (perceived susceptibility to skin cancer, perceived severity, perceived benefits of sun protection, perceived barriers, cues to action, self-efficacy) and their actual sun-protective behaviors (sunscreen use, protective clothing, shade-seeking).
ResultsPerceived barriers (e.g., forgetting to apply sunscreen, finding it inconvenient, disliking the feel) were the strongest predictor of not using sun protection. Perceived susceptibility and cues to action also significantly predicted behavior. Self-efficacy positively predicted sun protection. The study supports HBM but suggests targeting barriers is the priority in health promotion campaigns.
Memory Hook"It's not about knowing the risk — it's about removing the barriers." What stops health behavior matters more than what motivates it.
✅ StrengthSystematically tests all major HBM components; directly applicable to designing health promotion messages
❌ WeaknessSelf-report of behavior (social desirability bias); university students are a WEIRD, young, healthy sample; sun behavior is low-stakes compared to, e.g., HIV prevention
Newcomer et al
1999 · Cortisol, Stress & Cognitive Health
⭐
AimTo test whether elevated cortisol (the primary stress hormone) impairs verbal declarative memory in healthy humans
TypeDouble-blind, placebo-controlled true experiment
Pts51 healthy participants assigned to three groups: high-dose cortisol, low-dose cortisol, and placebo
ProcedureParticipants took cortisol or placebo tablets for 4 days. On day 4, they completed verbal memory tasks (paragraph recall). Blood cortisol levels were verified to confirm dosage compliance.
ResultsThe high-dose cortisol group performed significantly worse on verbal memory tests than both the low-dose and placebo groups. Low-dose cortisol showed no significant impairment. Demonstrates that chronically elevated stress hormones (as seen in chronic stress) cause measurable cognitive health damage.
📚 Originally studied in Paper 1 (Biological Approach — Hormones)
Memory Hook"Chronic stress shrinks your memory." Cortisol = the stress hormone that physically impairs brain function over time.
✅ StrengthDouble-blind design eliminates both experimenter and participant bias; cortisol levels verified
❌ WeaknessOnly 4 days — does not reflect long-term chronic stress; artificial administration ≠ natural stress response; small N
📊 Risk Factors & Prevalence — Key Studies
Padez et al
2005 · TV Time & Childhood Obesity · Portugal
AimTo investigate the relationship between television viewing, physical activity, and obesity in Portuguese children
TypeCross-sectional survey study
Pts4,511 Portuguese children aged 7–9 years from a nationally representative sample
ProcedureParents completed questionnaires about their child's TV watching habits (hours per day), physical activity levels, and diet. Children's height and weight were measured directly to calculate BMI. Overweight defined as BMI ≥ 25th percentile for age, obese as ≥ 30th.
Results20.3% of children were overweight; 11.3% were obese — much higher than previous Portuguese estimates. Watching TV ≥ 2 hours per day was a statistically significant and independent risk factor for obesity after controlling for diet. Physical activity was identified as a significant protective factor — children who were more physically active had lower obesity rates.
Memory Hook"More screen time = more weight gain." TV displaces physical activity and may increase snacking — a double risk.
✅ StrengthLarge, nationally representative sample; objective physical measurements (BMI) rather than self-report weight
❌ WeaknessCross-sectional — cannot determine causation (obese children may watch more TV, not vice versa); TV habits reported by parents (possible bias)
Hruby & Hu
2015 · Global Obesity Epidemiology · Systematic Review
AimTo review the global epidemiology of obesity — its prevalence, trends, and multi-factorial causes
TypeSystematic review and narrative synthesis
PtsStudies from multiple countries across different world regions; adult and child populations
ProcedureReviewed published literature on obesity prevalence rates worldwide, temporal trends since 1980, and the relative contributions of biological (genetics, metabolism), behavioral (diet, physical activity), and environmental/social (urbanization, food marketing, socioeconomic status) factors.
ResultsGlobal obesity prevalence has more than doubled since 1980. In 2014, over 600 million adults and 41 million children under 5 were obese or overweight. No country has successfully reversed its obesity epidemic at the population level. The causes are biopsychosocial: genetic susceptibility interacts with an "obesogenic environment" (cheap, calorie-dense food; sedentary lifestyles; stress; socioeconomic deprivation).
Memory Hook"Doubled in 35 years, no country has reversed it." Obesity is a global epidemic with no single cause and no easy fix.
✅ StrengthSynthesizes global data — comprehensive picture; highlights the multi-causal nature of obesity
❌ WeaknessRelies on self-reported BMI in many constituent studies; data quality varies by country; review cannot establish causation
📣 Health Promotion — Key Study
Langford et al
2015 · Whole-School Health Promotion · Cochrane Review
⭐
AimTo evaluate the effectiveness of "whole-school" approaches to health promotion across a range of health outcomes
TypeCochrane systematic review and meta-analysis of 67 studies
PtsStudies involving school-aged children across multiple countries and health domains
ProcedureReviewed 67 randomized and quasi-experimental studies evaluating whole-school health promotion programs — interventions that engage the entire school community (curriculum, environment, policy, family, community) rather than just individual-level health education. Outcomes assessed included smoking, alcohol use, physical activity, diet, and mental health.
ResultsWhole-school approaches were effective in reducing smoking, reducing alcohol use, improving physical activity, and improving dietary habits (particularly fruit and vegetable consumption). Effects on mental health were positive but more variable. Programs that involved the wider school environment (not just classroom instruction) had the strongest effects. Community and family involvement amplified outcomes.
Memory Hook"Change the school, change the child." Health promotion works best when it changes the environment, not just the individual's knowledge.
✅ StrengthCochrane review = gold standard of evidence; 67 studies across multiple health domains and countries
❌ WeaknessHeterogeneity of programs — hard to identify which specific components drive the effect; publication bias in included studies
Psychology of Human Relationships
Formation of relationships · Maintenance · Prosocial behavior & altruism
💘 Background: Formation of Relationships
Three key factors predict initial attraction and relationship formation:
1. Proximity (Propinquity Effect): Physical closeness increases the likelihood of forming a relationship. Festinger et al (1950) showed that residents of a housing complex were most likely to form friendships with those who lived physically nearest. Proximity increases exposure, and exposure increases liking (mere exposure effect).
2. Physical Attractiveness: Walster et al's (1966) "computer dance" found that physical attractiveness of a partner was the single strongest predictor of whether university students wanted a second date — outweighing personality, intelligence, and social skills. First impressions are heavily influenced by appearance.
3. Similarity: We are more attracted to those who share our values, attitudes, and interests. However, in early stages, physical attractiveness often dominates over similarity.
🔗 Background: Maintenance & Breakdown of Relationships
Rusbult's Investment Model (1983) predicts commitment to a relationship using three variables: satisfaction (how rewarding is the relationship?), quality of alternatives (how appealing is leaving?), and investment size (how much have you put in — time, shared friends, memories, effort?). High investment + high satisfaction + low alternatives = high commitment and relationship stability. People stay in relationships not only because they are happy, but because they have invested too much to leave.
Equity Theory proposes that both partners compare what they put in (inputs) to what they get out (outputs). Relationships feel fair when input/output ratios are balanced. Under-benefited partners are most likely to be dissatisfied and leave.
🤝 Background: Prosocial Behaviour & Altruism
Prosocial behavior refers to voluntary actions intended to benefit others (helping, sharing, cooperating, donating). Altruism is prosocial behavior motivated by genuine concern for others — not by self-interest.
Key explanations include: Social Identity Theory (we help in-group members more readily than out-group members — Drury 2009), Evolutionary explanations (kin selection — we help relatives to promote shared genes; reciprocal altruism — we help others expecting future help in return), and Empathy-Altruism Hypothesis (Batson) — genuine empathy produces genuine altruism, not just self-interested helping.
🟣 Formation of Relationships — Key Studies
Wedekind et al
1995 · Sweaty T-Shirt Study · Mate Selection
⭐
AimTo test whether humans use olfactory cues (smell) related to MHC genes to select genetically compatible mates
TypeLab experiment
Pts49 men and 44 women; all genotyped for MHC (major histocompatibility complex) gene variants
ProcedureMen wore plain white cotton t-shirts for two consecutive nights, avoiding scented products, spicy foods, and alcohol. Women then smelled the t-shirts from boxes and rated the odor for pleasantness and sexiness without knowing whose shirt it was. MHC similarity between raters and shirt-owners was then compared against ratings.
ResultsWomen significantly preferred the scent of men whose MHC genes were most dissimilar from their own. MHC dissimilarity in a couple produces offspring with broader immune system coverage (greater pathogen resistance). Crucially, women on oral contraceptives showed a reversed preference — toward MHC-similar men — suggesting hormones affect mate selection cues.
📚 Originally studied in Paper 1 (Biological Approach — Pheromones & Evolution)
Memory Hook"You're attracted to the immune system you don't have." MHC dissimilarity = healthier future children.
✅ StrengthControlled design; evolutionary rationale is clear and testable; unexpected oral contraceptive finding adds depth
❌ WeaknessArtificial lab setting; scent of a t-shirt ≠ real-world attraction; cultural and environmental confounds in mate choice ignored
Walster et al
1966 · Computer Dance Study · Physical Attractiveness
⭐
AimTo investigate which personal characteristics most strongly predict romantic attraction during an initial encounter
TypeField experiment with a natural social context (a university dance)
Pts752 first-year university students at the University of Minnesota, USA
ProcedureStudents were told they had been matched by a computer for a dance based on compatibility. In reality, they were randomly paired. Before the dance, experimenters secretly and independently rated each participant's physical attractiveness. At the dance's intermission and 6 months later, participants completed questionnaires about how much they liked their partner and whether they wanted to see them again. Physical attractiveness, IQ, personality (measured by psychometric tests), and social skills were all assessed and correlated with liking ratings.
ResultsPhysical attractiveness of the partner was by far the strongest predictor of liking and desire for a second date — outweighing personality scores, intelligence, and social skills. The originally-hypothesized "matching effect" (people prefer partners of similar attractiveness to themselves) was not supported at this early stage. Both men and women showed the attractiveness effect equally.
Memory Hook"Looks win the first round." In initial attraction, nothing predicts liking as strongly as physical attractiveness.
✅ StrengthLarge sample (752); naturalistic dance setting increases ecological validity; independent rating of attractiveness avoids self-report bias
❌ WeaknessShort-term (intermission only initially); only measures initial attraction, not long-term relationship quality; student sample; US-specific cultural beauty standards
Festinger, Schachter & Back
1950 · Westgate Housing Study · Proximity
AimTo investigate whether physical proximity (closeness) predicts friendship formation in a naturally occurring community
TypeNaturalistic correlational study
Pts270 married student couples newly arrived at the Westgate housing project at MIT, Boston
ProcedureAfter residents had settled in, each was asked to name their three closest friends within the housing project. Researchers then mapped how physical distance between apartments related to friendship choices. They also recorded "functional distance" — proximity to high-traffic areas like mailboxes and stairwells — which influenced cross-floor friendships.
ResultsProximity was the strongest predictor of friendship: residents were most likely to be friends with next-door neighbors (41%) and least likely to be friends with those at the far end of their floor (only 10%). Those whose apartments were near stairwells and mailboxes (high functional distance) had friends on multiple floors. Familiarity through repeated contact (mere exposure) generated liking.
Memory Hook"You befriend who you bump into." Proximity → familiarity → liking. The mere exposure effect in real life.
✅ StrengthNaturalistic setting; friendship formation studied as it actually happened (not in a lab); reveals functional vs. physical distance
❌ WeaknessHomogenous sample (MIT married students, 1950s); cannot separate proximity from shared interests (people near stairwells may simply be more sociable); historical limitations
🔗 Relationship Maintenance — Key Study
Rusbult
1983 · Investment Model · Relationship Commitment
AimTo test whether relationship commitment can be predicted by satisfaction, investment size, and quality of alternatives
TypeLongitudinal self-report study with repeated measures
Pts34 university students in dating relationships, assessed multiple times over 7 months
ProcedureParticipants completed questionnaires at regular intervals measuring: satisfaction with the relationship, quality of available alternatives (how appealing would leaving be?), investment size (how much time, emotion, shared memories had been accumulated?), and overall commitment level. Whether couples stayed together or broke up was recorded at the end.
ResultsAll three variables significantly predicted commitment: high satisfaction, high investment, and low-quality alternatives each independently predicted higher commitment. Investment size was a particularly important predictor — participants stayed even when satisfaction was moderate, if they had invested heavily. Commitment in turn predicted whether the couple remained together. The formula: Commitment ≈ Satisfaction − Quality of Alternatives + Investment.
Memory Hook"People stay because leaving costs too much." You don't just need to be happy — you need nowhere better to go, and too much to lose.
✅ StrengthLongitudinal design captures change over time; all three model components independently validated
❌ WeaknessVery small sample (34 students); self-report of commitment and satisfaction subject to social desirability; only young dating relationships studied
🤝 Prosocial Behaviour — Key Study
Drury et al
2009 · Crowd Disasters & Prosocial Behaviour
⭐
AimTo explore whether shared social identity explains prosocial cooperation among strangers in crowd disasters
TypeQualitative study — thematic analysis of in-depth interviews
PtsSurvivors of 11 different crowd disaster events (including the Bradford City fire, Hillsborough disaster, and the 2005 London bombings)
ProcedureSurvivors were interviewed in depth about their experiences during the disaster — specifically about how they felt about the people around them and how they behaved (helped, ignored, competed for exits, etc.). Transcripts were analyzed for themes relating to shared social identity and its influence on prosocial behavior.
ResultsSurvivors consistently reported that during the crisis, they felt a strong sense of unity and shared fate with those around them — even strangers. This sense of shared identity prompted spontaneous helping (carrying injured strangers, giving up places in queues, sharing resources) that they described as automatic, not calculated. Social identity — being "in the same boat" — unlocked altruistic behavior among people who had never met.
📚 Originally studied in Paper 1 (Sociocultural — Social Identity Theory)
Memory Hook"A shared crisis creates a temporary community." When threat is equal, strangers become in-group members — and we help our in-group.
✅ StrengthExtremely high ecological validity — real disasters, real consequences; documents behavior that would be unethical to simulate
❌ WeaknessRetrospective recall — memory of emotionally intense events may be distorted; researcher interpretation of themes is subjective; small and varied sample
Key Definitions
Define these in your introduction — always link the definition directly to the question prompt
🔴 Abnormal Psychology
Validity (of diagnosis)
The extent to which a diagnosis accurately identifies a genuine, distinct mental disorder — i.e., whether it measures what it claims to measure. A valid diagnosis predicts prognosis and treatment response.
Reliability (of diagnosis)
The extent to which different clinicians, given the same patient, reach the same diagnosis. High inter-rater reliability means diagnostic categories are applied consistently. Low reliability undermines validity.
Clinical (Diagnostic) Bias
The tendency for a clinician's personal characteristics (culture, ethnicity, gender, prior expectations) to systematically skew their diagnostic judgments, leading to over- or under-diagnosis of certain groups.
Cognitive Triad (Beck)
Beck's model of depression proposes that depressed individuals hold systematic negative views about themselves ("I am worthless"), the world ("everything is hopeless"), and the future ("nothing will improve") — collectively maintaining the disorder.
Etiology
The study of the causes or origins of a disorder. In IB Psychology, etiology of a disorder is explained from biological, cognitive, and sociocultural perspectives.
Concordance Rate
In twin studies, the percentage of twin pairs in which both twins share the same trait or disorder. MZ (identical) concordance > DZ (fraternal) concordance indicates a genetic component.
Gene-Environment Interaction
When the effect of a genetic variant on behavior depends on the environment to which the individual is exposed. Neither genes nor environment alone determine the outcome — they interact (Caspi et al, 2003).
Culturally Adapted Therapy
Psychotherapy that has been modified to be consistent with the cultural values, beliefs, language, and practices of the client's ethnic or cultural group, to improve engagement and effectiveness.
🟡 Developmental Psychology
Attachment
A deep, enduring emotional bond between an infant and a caregiver, characterized by the infant using the caregiver as a secure base for exploration and a safe haven in distress. Bowlby proposed this is innate and evolutionarily adaptive.
Maternal Deprivation Hypothesis
Bowlby's theory that prolonged separation from the primary caregiver during the critical period (roughly birth to 3 years) causes permanent and irreversible damage to intellectual, social, and emotional development.
Critical Period
A biologically determined window of time during which an organism is especially sensitive to certain environmental experiences. For Bowlby, the critical period for attachment formation is approximately birth to 2–3 years.
Monotropy
Bowlby's concept that infants are biologically predisposed to form one primary, special attachment bond (usually with the mother) that is qualitatively different from other attachments and forms the template for all future relationships.
Gender Schema
A cognitive framework that organizes knowledge about gender — what behaviors, traits, roles, and objects are "for boys" versus "for girls." Once activated, schemas guide attention and memory toward schema-consistent information.
Enculturation
The process by which a child learns the norms, values, behaviors, and expectations of their cultural group, primarily through socialization agents such as parents, peers, school, and media.
Secure Attachment (Type B)
The most common attachment pattern (~65–70%): the child uses the caregiver as a secure base, is distressed by separation, and is comforted by reunion. Associated with sensitive, responsive caregiving.
Insecure Avoidant (Type A)
An attachment pattern (~20–22%) where the infant shows little distress at separation and actively avoids or ignores the caregiver at reunion. Associated with consistently unresponsive caregiving.
🟢 Health Psychology
Health Belief Model (HBM)
A cognitive model (Rosenstock, 1966) predicting health-related behavior. Key components: perceived susceptibility, perceived severity, perceived benefits, perceived barriers, cues to action, and self-efficacy.
Perceived Barriers
In the HBM, the individual's perception of the obstacles that make a health behavior difficult or costly — e.g., time, money, inconvenience, discomfort. Research consistently finds this is the strongest negative predictor of health behavior.
Biopsychosocial (BPS) Model
Engel's (1977) model proposing that health and illness result from the interaction of biological (genetics, physiology), psychological (emotions, cognitions, behavior), and social (culture, relationships, SES) factors — rejecting purely biomedical explanations.
Risk Factor
A variable that increases the probability of developing a health problem. Risk factors can be biological (genetic susceptibility), behavioral (sedentary lifestyle), or social/environmental (poverty, food deserts).
Protective Factor
A variable that reduces the probability of developing a health problem or buffers against the impact of risk factors. Examples: physical activity (against obesity), social support (against depression), education (against risky health behaviors).
Prevalence
The proportion of a population with a particular condition at a specific point in time (point prevalence) or over a defined period (period prevalence). Different from incidence, which measures new cases only.
Health Promotion
The process of enabling people to increase control over and improve their health. Operates at individual (education, skills), community (social norms, support networks), and structural/policy levels (legislation, environmental design).
Cortisol
The primary glucocorticoid stress hormone, produced by the adrenal cortex in response to HPA-axis activation. Chronic elevation of cortisol impairs immune function, memory, and mood (Newcomer et al, 1999).
🟣 Psychology of Human Relationships
Prosocial Behaviour
Voluntary behavior intended to benefit another person or group, including helping, sharing, donating, comforting, and cooperating. May or may not be motivated by altruistic intent.
Altruism
A form of prosocial behavior motivated by genuine concern for others' wellbeing, with no expectation of personal reward. Contrasted with self-interested helping (e.g., reciprocal altruism, which involves expectation of future return).
Proximity (Propinquity) Effect
The tendency to form relationships with those who are physically nearby. Proximity increases repeated exposure, and repeated exposure increases liking (mere exposure effect — Zajonc, 1968). Festinger et al (1950) provided classic evidence.
Investment Model
Rusbult's (1983) model proposing that relationship commitment is determined by satisfaction, quality of alternatives, and investment size. Commitment = Satisfaction − Quality of Alternatives + Investment. Predicts relationship persistence.
Equity Theory
Walster et al's theory that satisfying relationships are those where both partners perceive an equal ratio of inputs (what they contribute) to outputs (what they receive). Inequity leads to dissatisfaction — especially for the under-benefited partner.
MHC (Major Histocompatibility Complex)
A set of genes encoding proteins involved in immune system recognition. MHC dissimilarity between partners produces offspring with broader immune system coverage. Wedekind (1995) showed women prefer the scent of MHC-dissimilar men.
Mere Exposure Effect
The phenomenon whereby repeated exposure to a stimulus (person, object, sound) increases positive feelings toward it. Proposed by Zajonc (1968) — familiarity breeds liking, not contempt. Explains why proximity predicts friendship (Festinger, 1950).
Reciprocal Altruism
Trivers' (1971) evolutionary concept: individuals help non-relatives when there is a reasonable expectation of future reciprocation. Adaptive because it creates mutual benefit over time, even without genetic relatedness.