Exhaustive Review of Psychological Studies: Biological, Cognitive, and Sociocultural Approaches

The Biological Approach: Brain and Behavior, Localization, and Neuroplasticity

HM Milner (1966) * Chapter/Lesson: The Brain and Behavior (Techniques used to study the brain/Localization). * Aim: To better understand the effects of the surgery sustained by HM. * Sample: A single participant, HM. * Key Findings: HM’s case study demonstrated that the hippocampus is essential for the process of consolidating new memories. The damage he sustained prevented the formation of new long-term memories—specifically episodic and semantic memories—while leaving older memories intact. This finding suggests the hippocampus functions as a processing centre rather than a storage site. Furthermore, it suggests that memory consists of separate systems, as HM's procedural and working memory remained unaffected.
Draganski (2004) * Chapter/Lesson: The Brain and Behavior (Neuroplasticity). * Aim: To determine whether learning a new skill, specifically juggling, would affect the brains of participants. * Sample: $24$ participants ( $21$ females and $3$ males) with a mean age between $20$ and $24$ . * Key Findings: Learning to juggle resulted in an increase in grey matter in the mid-temporal areas, which are regions associated with visual memory, as evidenced by MRI scans. After participants stopped practicing for a period of $3$ months, this increase in grey matter decreased. No changes were observed in the control group, which indicates the effect was specifically due to the learning process.
Maguire (2000) * Chapter/Lesson: The Brain and Behavior (Localization-Neuroplasticity). * Aim: To investigate whether the brains of London taxi drivers would differ as a result of their exceptional knowledge of the city and the extensive hours spent navigating London's streets. * Sample: $16$ right-handed male London taxi drivers and $50$ right-handed males who did not drive taxis (controls). Participants had to have completed the "Knowledge" test and held their license for at least $1.5$ years. The sample included a range of ages to ensure age was not a confounding variable. * Key Findings: Taxi drivers possessed larger posterior hippocampi and smaller anterior hippocampi compared to the control group. The size of the posterior hippocampus was positively correlated with the number of years of driving experience. This suggest that spatial navigation is localized in the hippocampus and that this brain structure can change with use.

The Biological Approach: Neurotransmitters and Their Effects on Behavior

Antonova (2011) * Chapter/Lesson: The Brain and Behaviour (Neurotransmitters). * Aim: To determine the role of acetylcholine in the encoding of spatial memories by examining the effect of scopolamine on hippocampus activity during a spatial navigation task. * Sample: $20$ healthy male adults with a mean age of $28$ years old. * Key Findings: Participants who were administered scopolamine exhibited reduced hippocampal activation and poorer performance in spatial memory during the arena task compared to those given a placebo (as measured by fMRI). This suggests acetylcholine plays a vital role in the encoding of spatial memory.
Rogers and Kesner (2003) * Chapter/Lesson: The Brain and Behaviour (Neurotransmitters). * Aim: To determine the role of acetylcholine in the formation of spatial memory. * Sample: $30$ rats. * Key Findings: Rats injected with scopolamine committed more errors and were slower to learn the maze; however, the retrieval of previously learned paths was not affected. This suggests acetylcholine is important for the encoding and consolidation of spatial memory, rather than its retrieval.
Prevot et al (2019) * Chapter/Lesson: The Brain and Behaviour (Neurotransmitters). * Aim: To determine the effect of an $\alpha5$ -GABA receptor agonist on spatial working memory in impaired mice. * Sample: Mice suffering from memory impairment caused by chronic stress, as well as older mice demonstrating memory impairment. * Key Findings: Mice given a GABA agonist showed improved spatial working memory in the Y-maze compared to a placebo group, performing at a level similar to healthy mice. Researchers also observed increased hippocampal cell growth. This suggests GABA activity can restore memory function and potentially reverse the effects of aging and stress.

The Biological Approach: Hormones and Pheromones

McGaugh and Cahill (1995) * Chapter/Lesson: Hormones (also applicable as an example for Flashbulb Memory). * Aim: To study the role of emotion in the creation of memories. * Sample: Participants were divided into $2$ groups (no other specific information provided). * Key Findings: Emotional arousal, triggered by adrenaline, enhances memory consolidation, particularly for emotional events.
Newcomer et al (1999) * Chapter/Lesson: Hormones. * Aim: To investigate whether high levels of the stress hormone cortisol interfere with verbal declarative memory. * Sample: Employees or students at the Washington University Medical Center. Exclusions: pregnancy, history of mental illness, head trauma, or illnesses treated with corticosteroids. * Key Findings: High levels of cortisol were found to impair memory, specifically verbal declarative memory.
Wedekind (1995) * Chapter/Lesson: Hormones (Pheromones). * Aim: To determine whether one's MHC (Major Histocompatibility Complex) would affect mate choice. * Sample: $49$ female and $44$ male students from the University of Bern, Switzerland. The sample included a wide variance of MHC. Researchers noted if women were taking oral contraceptives. Courses: Women (biology and psychology); Men (chemistry, physics, and geography). * Key Findings: Women rated the scent of MHC-dissimilar men as more pleasant and attractive than MHC-similar men. This preference was reversed in women taking oral contraceptives, who tended to prefer MHC-similar scents.
Zhou (2014) * Chapter/Lesson: Hormones (Pheromones). * Aim: To identify the effect of androstadienone (AND) and estratetraenol (EST) on heterosexual and homosexual men and women. * Sample: Four groups of healthy non-smokers: $24$ heterosexual males, $24$ heterosexual females, $24$ homosexual males, and $24$ bisexual or homosexual females. * Key Findings: Exposure to AND increased the likelihood that heterosexual females and homosexual males perceived ambiguous human movement (point-light walkers) as more masculine, suggesting a sex-specific bias in social perception. AND had no significant effect on heterosexual males or homosexual females. EST produced the opposite pattern, biasing heterosexual males toward perceiving walkers as more feminine; this effect was not significant in bisexual or lesbian women.

The Biological Approach: Genetics and Behavior

Weissman et al (2005) * Note: This study is designated for SAQ (Short Answer Question) only. * Chapter/Lesson: Genetics (Kinship and twin studies - Evolutionary psychology). * Aim: To investigate whether Major Depressive Disorder (MDD) shows a genetic or familial pattern across three generations, and whether risk increases when depression is present in both parents and grandparents. * Sample: $161$ grandchildren and their families (parents and grandparents). Grandparents included clinically diagnosed depressed patients and a non-depressed control group from the same community. * Key Findings: Higher rates of psychiatric disorders were found in grandchildren when both parents and grandparents had a history of depression. By age $12$ , $59.2\%$ of grandchildren showed a psychiatric disorder, most commonly anxiety. Risk increased with the severity of parental depression; however, parental depression alone did not significantly increase risk in grandchildren unless there was also a grandparental history of depression.
Bailey and Pillard (1990) * Note: This study is designated for SAQ only. * Chapter/Lesson: Genetics (Kinship and twin studies). * Aim: To investigate whether sexual orientation has a genetic component by comparing concordance rates in monozygotic twins (MZ), dizygotic twins (DZ), and adoptive brothers, and to explore if childhood gender nonconformity (CGN) predicts adult orientation. * Sample: Male participants recruited through gay publications ( $MZ$ twins, $DZ$ twins, and non-related adoptive brothers), raised together in similar environments. * Key Findings: Concordance rates for homosexuality were highest in $MZ$ twins ( $52\%$ ), followed by $DZ$ twins ( $22\%$ ), and lowest in adoptive brothers ( $11\%$ ). Later comparisons found non-twin brothers had a rate of $9.2\%$ . While these findings associate closer genetic relatedness with higher similarity, CGN did not predict adult sexual orientation, though $MZ$ twins showed high similarity in CGN levels.
Caspi et al (2003) * Chapter/Lesson: Genetics (Genetics and depression). * Aim: To investigate whether there is a gene–environment interaction ( $G \times E$ ) between the $5-HTT$ serotonin transporter gene and stressful life events in predicting depression. * Sample: $847$ participants from a longitudinal New Zealand cohort, all aged $26$ at assessment, grouped by genotype: two short alleles, one short/one long, or two long alleles. * Key Findings: Individuals with one or two short alleles of the $5-HTT$ gene showed higher rates of depression and suicidal ideation, but only when exposed to stressful life events. Those with two long alleles were more resilient. This supports a gene–environment interaction model where genetic variation influences vulnerability to environmental stressors.

The Cognitive Approach: Cognitive Processing and Schema Theory

Bransford and Johnson (1972) * Chapter/Lesson: Cognitive Processing (Schema theory). * Aim: To determine whether schema activation would improve understanding and recall of an ambiguous text. * Sample: $52$ participants divided into three conditions: no topic ( $n=17$ ), topic after ( $n=17$ ), and topic before ( $n=18$ ). * Key Findings: The topic-before condition showed the highest performance (comprehension $M = 4.50$ ; recall $M = 5.83$ ), compared to the no-topic group (comprehension $M = 2.29$ ; recall $M = 2.82$ ). The topic-after group performed worst (comprehension $M = 2.12$ ; recall $M = 2.65$ ). This indicates schemas must be triggered during processing to be effective. * Study Evaluation: Independent samples design might include participant variability. The artificial task lowers ecological validity, but high control increases internal validity. Reliable and replicable, but alternative explanations like general memory ability cannot be ruled out. * Theory Evaluation (Schema Theory): Testable and supported by research/biology; widely applicable; however, concepts are vague and not directly observable. Can predict general patterns but not specific individual recall.
Bartlett (1932) * Chapter/Lesson: Cognitive Processing (Schema theory). * Aim: To investigate how the memory of a story (The War of the Ghosts) is affected by previous knowledge. * Sample: British participants. * Study Evaluation: Limitations in reliability and internal validity due to lack of standardization (no fixed intervals or controlled variables). However, it has high ecological and theoretical validity for introducing the core concept of schemas.

The Cognitive Approach: Memory Models

HM Milner (1966) - Applied to MSM * Chapter/Lesson: Cognitive Processing (Multi-store Model). * Theory Evaluation (MSM): Historically important; explains memory via encoding, storage, and retrieval. HM supports separate $STM$ and $LTM$ systems. Critiques: Too simplistic and linear ( $STM \rightarrow LTM$ ). Logie (1999) argues $STM$ is a "workstation" integrating info with $LTM$ . It fails to explain memory distortion, one-trial emotional learning, or why rehearsal doesn't always lead to storage.
Glanzer and Cunitz (1966, study 2) * Chapter/Lesson: Cognitive Processing (Multi-store Model). * Aim: To investigate the recency effect in serial position recall and how short delays ( $10s$ , $30s$ distraction) affect it, testing the separation of $STM$ and $LTM$ . * Sample: $46$ army enlisted men; repeated measures design. * Key Findings: Immediate recall showed primacy and recency effects. With a $10$ -second delay, the recency effect was reduced; at $30$ seconds, it disappeared ("no trace"), while primacy remained stable. Supports $STM$ (recency) as short-lived without rehearsal. * Study Evaluation: High internal validity but low ecological validity (artificial task) and limited generalizability.
Landry and Bartling (2011) * Chapter/Lesson: Cognitive Processing (Working Memory Model). * Aim: To investigate if articulatory suppression would influence the recall of a written list of phonologically dissimilar letters. * Sample: $34$ undergraduate psychology students; independent samples design. * Key Findings: Articulatory suppression significantly reduced accuracy: experimental group ( $45\%$ ) vs control ( $76\%$ ), $p \le 0.01$ . Findings support the existence of the phonological loop and the necessity of articulatory rehearsal. * Study/Theory Evaluation: High internal validity but artificial task. The $WMM$ explains multitasking better than $MSM$ and is supported by brain imaging, but the Central Executive remains poorly defined/measurable.

The Cognitive Approach: Thinking and Decision Making

Englich and Mussweiler (2001) * Chapter/Lesson: Cognitive Processing (Thinking and decision making). * Aim: To determine the effect of a prosecutor's sentencing suggestion on a judge’s decision. * Sample: $19$ young trial judges ( $15$ male, $4$ female), average age $29.37$ , mean experience $9.34$ months. * Key Findings: The prosecutor's sentence acted as an anchor. Low anchor ( $2$ months) led to a mean sentence of $\approx 18.78$ months; high anchor ( $34$ months) led to $\approx 28.70$ months. Demonstrates anchoring bias and System 1 thinking. * Study/Theory Evaluation: High internal validity; ecologically relevant (judges). Theory is reductionist, simplifying thinking into two systems, and lacks clarity on System 1 vs 2 (e.g., speed doesn't always equal System 1).
Tversky and Kahneman (1974) * Chapter/Lesson: Cognitive Processing (Thinking and decision making). * Aim: To investigate whether number order (ascending vs descending) influences estimates, testing anchoring bias. * Sample: High school students. * Key Findings: Ascending ( $1 \rightarrow 8$ ) median estimate was $512$ ; descending ( $8 \rightarrow 1$ ) was $2250$ (Actual: $40320$ ). The first number acted as a cognitive anchor for System 1 processing under time pressure.

Reliability of Cognitive Processes

Loftus & Palmer (1974) [Study 1] * Chapter/Lesson: Reconstructive memory. * Aim: To investigate if leading questions affect speed estimation. * Sample: $45$ students. * Key Findings: Verb intensity influenced speed estimates: "smashed" ( $40.8\,mph$ ) vs "contacted" ( $31.8\,mph$ ), $p \le 0.005$ . Suggests language can distort recall via schemas or response bias.
Loftus & Pickrell (1995) * Chapter/Lesson: Reconstructive memory. * Aim: To determine if false autobiographical memories can be created via suggestion. * Sample: $3$ males, $21$ females. * Key Findings: $25\%$ formed a false memory ("lost in a mall"), though these were less detailed and held with lower confidence than real memories.
Bahrick et al (1975) * Chapter/Lesson: Reliability of memory. * Aim: To investigate long-term reliability of autobiographical memory (names/faces of schoolmates). * Sample: $392$ participants, aged $17-74$ , out of school for $2$ weeks to $57$ years. * Key Findings: Recognition remained high ( $80-90\%$ ) even after decades; free recall declined ( $\approx 30\%$ after $48$ years). Recognition is more reliable than recall.
Yuille & Cutshall (1986) * Chapter/Lesson: Reliability of memory. * Aim: To see if leading questions affect memory of a real crime scene. * Sample: $13$ out of $21$ eyewitnesses to a real violent crime. * Key Findings: Memory was highly accurate ( $79-84\%$ ) after $4$ months; participants resisted misleading questions (e.g., rejecting a fake "yellow panel"). Challenges Loftus & Palmer.

Emotion and Cognition: Flashbulb Memory (FBM)

Sharot et al (2007) * Aim: Role of biological factors on flashbulb memories. * Sample: $24$ participants in NYC on $9/11$ . * Key Findings: Proximity to the WTC led to more vivid memories and higher amygdala activation (fMRI) during recall compared to distant participants.
Brown & Kulik (1977) * Aim: To see if surprising/significant events cause flashbulb memories. * Sample: $40$ black and $40$ white American males. * Key Findings: $90\%$ recalled rich detail of public/personal events. Personal relevance mattered: $75\%$ of Black participants had FBMs for MLK’s assassination vs $33\%$ of White participants.

The Sociocultural Approach: Individual and the Group

Abrams et al (1990) * Chapter/Lesson: Social Identity Theory (SIT). * Aim: To see if in-group identity affects conformity. * Sample: $50$ psychology students. * Key Findings: Conformity in $77\%$ of participants ( $32\%$ overall), peaking in the in-group public condition ( $M = 5.23$ ) and dropping in out-group public ( $M = 0.75$ ). * Theory (SIT - Tajfel, 1979): Identity derived from group membership via social categorization, social comparison, and boosting self-esteem through in-group favoritism.
Drury et al (2009) * Chapter/Lesson: Social Identity Theory. * Aim: Shared identity and helping in emergencies. * Sample: $40$ students ( $7$ male, $33$ female). * Key Findings: Shared social identity increased helping behaviour and reduced pushing in emergencies.
Bandura (1961) * Theory: Social Cognitive Learning Theory (SCT): Behavior is learned via observing/imitating models through vicarious reinforcement, attention, retention, motivation, and self-efficacy. * Aim: Demonstrate children imitate adult aggression. * Sample: $36$ boys, $36$ girls (mean age $52$ months). * Key Findings: Aggressive-model group showed significantly higher imitation. Same-sex models had stronger influence.

Stereotypes, Cultural Dimensions, and Acculturation

Hamilton and Gifford (1976) * Aim: To investigate illusory correlations. * Sample: $40$ American undergraduates. Group A ( $26$ people) and Group B ( $13$ people - minority). * Key Findings: Participants overestimated negative behaviors in Group B, despite equal proportions, creating a distinctiveness-based illusory correlation.
Steele and Aronson (1995) * Aim: Effect of stereotype threat on African American test performance. * Sample: $114$ undergraduates (Black and White). * Key Findings: African Americans performed worse when the test was framed as "diagnostic of intellectual ability," but equally well when framed as "problem-solving."
Berry (1967) * Chapter/Lesson: Cultural Dimension (Individualism vs Collectivism). * Aim: Compare conformity in rice farming (collectivist) and hunting/fishing (individualist) societies. * Sample: $120$ per group: Temne, Inuit, and Scots (control). * Key Findings: Temne (collectivist) had highest conformity ( $\approx 9$ ), Scots moderate ( $\approx 4$ ), Inuit lowest ( $\approx 2-3$ ).
Fagot (1978) * Chapter/Lesson: Enculturation. * Aim: Parental influence on gender roles. * Sample: $24$ white middle-class families (child $20-24$ months). * Key Findings: Parents reinforced traditional gender roles via positive/negative responses, often unconsciously.
Lueck and Wilson (2010) * Chapter/Lesson: Acculturation. * Aim: Variables predicting acculturative stress. * Sample: $2095$ Asian Americans. * Key Findings: $70\%$ experienced acculturative stress. Protective factors: bilingualism, family cohesion. Risk factors: English-only preference, discrimination.

Psychology of Human Relationships: Attraction

Ronay and von Hippel (2010) * Chapter/Lesson: Biological Theories of Attraction. * Aim: Male risk-taking in presence of attractive females. * Sample: $96$ young adult Australian male skateboarders (mean age $21.58$ ). * Key Findings: Riskier behavior and higher testosterone when observed by an attractive female. Heart rate was not significantly different.
Markey and Markey (2007) * Chapter/Lesson: Similarity-Attraction Model. * Aim: Similarity and partner choice. * Sample: Study 1 (Large self-selected student sample); Study 2 ( $106$ heterosexual young couples). * Key Findings: Participants preferred partners similar in attitudes/personality. Satisfying relationships involved partial similarity plus some complementary traits.
Taylor et al. (2011) * Chapter/Lesson: Matching Hypothesis (Walster, 1966). * Aim: Matching hypothesis in online dating. * Sample: $60$ male and $60$ female 'initiators' on dating sites. * Key Findings: No support for matching; initiators contacted people more attractive than themselves, "aiming higher."
Moreland and Beach (1992) * Chapter/Lesson: Mere-Exposure Effect (Zajonc, 1968). * Aim: Exposure frequency and attractiveness. * Sample: $130$ undergrads in a large lecture hall. * Key Findings: Confederate seen most often ( $15$ times) was rated most attractive/likable.
Gupta & Singh (1982) * Aim: Success of arranged vs love marriages. * Sample: $50$ Indian couples ( $25$ love, $25$ arranged). * Key Findings: Love marriages: love decreased ( $70/91$ to $40/91$ after $10$ years). Arranged marriages: love increased ( $58/91$ to $68/91$ after $10$ years).

Communication and Why Relationships End

Collins & Miller (1994) * Chapter/Lesson: Communication in Personal Relationships. * Theory: Social Penetration Theory: Stages include Orientation, Exploratory, Affective, and Stable. Disclosure follows cost-benefit analysis. * Key Findings (Meta-analysis): Strong reciprocal link between self-disclosure and liking.
Levenson & Gottman (1983) * Aim: Marital satisfaction and communication style. * Sample: $30$ US married couples. * Key Findings: Distressed couples (negative communication/"Four Horsemen") had significantly higher physiological arousal (heart rate, galvanic skin response) during conflict.
Mitnick et al. (2009) * Theory: Duck’s Phase Model (2007): Breakdown stages: Intra-psychic, Dyadic, Social, Grave-dressing. * Key Findings (Meta-analysis): Nearly $6000$ samples; first-time parents showed significant decline in relationship satisfaction compared to childless couples.
Felmlee (1995) * Theory: Fatal Attraction Hypothesis (FAH): Qualities that initially attract (e.g., confidence) later become sources of irritation (e.g., arrogance). * Sample: $301$ UC students. * Key Findings: $30\%$ of breakups followed FAH patterns: "fun to foolish," "strong to domineering," and "spontaneous to unpredictable."