Research Psychology
Investigate psychology properly: understand its major theoretical traditions, how psychological evidence is produced and judged, where the field disagrees with itself, and how to form a defensible view of my own.
This roadmap takes you from foundational methodology and early theoretical schools through modern empirical psychology, the replication crisis, and independent synthesis. You will investigate eleven distinct territories, learning how evidence is produced, where paradigms conflict, and how to evaluate empirical claims. By the end of this plan, you will be able to critically appraise primary psychological literature, compare competing explanations across major schools of thought, and write a defensible position paper on an unresolved psychological debate.
By the end: You will be able to critically deconstruct peer-reviewed psychological studies, trace conflicting theories back to their foundational paradigms, and write a structured, defensible literature review evaluating an open question in human psychology.
This is the map — make this roadmap yours
It shows what this journey generally looks like. Tell Kaidoro your version of the goal and it builds the plan around where you are actually starting, what to do first, the hours you really have, and what you have already finished.
Psychological Epistemology and Research Methods
Establish the foundational vocabulary and methodology required to read psychological science: operational definitions, experimental design, and statistical inference.
- Learn the anatomy of psychological investigation and validity~6hMethod
Before reading any psychological literature, you must know how researchers translate mental concepts into measurable numbers and where that translation breaks down.
You'll learn
- Operationalisation — the process of turning an unobservable construct into a measurable variable
- Construct validity — the degree to which a test measures what it claims to measure
- Internal validity — the extent to which an experiment demonstrates a true causal relationship
- Demand characteristics — subtle cues that make participants aware of what the experimenter expects
Examine how abstract psychological constructs like intelligence, anxiety, or attention are operationalised into measurable variables. You will study internal, external, construct, and statistical conclusion validity to understand what makes an experimental claim reliable versus flawed.
Done when: you have written a 500-word critique of a hypothetical experiment identifying at least three distinct threats to construct or internal validity.
How to work through it
- Read an introductory chapter on operationalisation and measurement scales
- Define the four major types of experimental validity in your research notebook
- Identify the difference between correlational, quasi-experimental, and experimental designs
- Map out common confounds including demand characteristics and experimenter bias
- Read a landmark methodological paper on statistical inference in psychology~5hRead
Psychology is heavily quantitative; understanding what p-values actually measure prevents naive misinterpretations of study results.
You'll learn
- Null hypothesis significance testing (NHST) — the default statistical paradigm in psychological research
- Effect size — a quantitative measure of the magnitude of an experimental phenomenon
- Statistical power — the probability of correctly rejecting a false null hypothesis
- Type I error — rejecting the null hypothesis when it is actually true
Read Cohen's foundational 1994 paper 'The Earth is Round (p < .05)' in American Psychologist. Annotate how null hypothesis significance testing (NHST) is frequently misunderstood by practitioners and why statistical significance does not equate to practical effect size.
Done when: you have produced a one-page summary contrasting p-values with effect sizes (Cohen's d) and confidence intervals.
How to work through it
- Locate and read Cohen (1994, American Psychologist)
- Highlight the author's primary criticisms of the deductive logic behind NHST
- Note the definitions of Type I error, Type II error, and statistical power
- Write the one-page explanatory summary in your own words
- Synthesise an experimental deconstruction checklist~4hSynthesise
Creating your own evaluation rubric turns passive comprehension of methodology into an active analytical tool.
You'll learn
- Ecological validity — the extent to which research findings apply to real-world settings
- WEIRD bias — the overreliance on Western, Educated, Industrialized, Rich, and Democratic participant samples
Synthesise what you have learned about experimental methods into a standard 10-point rubric that you will apply to primary research papers throughout the rest of this roadmap.
Done when: you have a documented 10-point rubric covering sampling, control groups, construct operationalisation, power, and ecological validity.
How to work through it
- List the essential questions a reader must ask about sample size and demographics
- Draft criteria for assessing independent and dependent variable operationalisation
- Include checks for statistical reporting and potential confounding variables
- Test the rubric against one published open-access paper
Biological and Evolutionary Foundations
Investigate the biological substrate of behaviour: neuroanatomy, neurotransmission, genetic inheritance, and evolutionary psychology.
- Map neuroanatomy and mechanisms of neural communication~7hMethod
Understanding the physical substrate of mind prevents biological illiteracy when evaluating neuropsychological claims.
You'll learn
- Action potential — an electrical impulse that travels along the axon of a neuron
- Synaptic transmission — the relay of signals across the synapse via neurotransmitters
- Neuroplasticity — the nervous system's capacity to modify its structure and function over time
- Limbic system — a complex system of brain structures involved in emotion and memory
Study the macrostructure of the human brain (cerebral cortex, limbic system, brainstem) and the micro-level mechanics of the action potential and synaptic transmission. Focus on how neurotransmitter systems relate to psychological states without falling into crude chemical reductionism.
Done when: you can draw and explain a diagram of an action potential and state the primary functional roles of dopamine, serotonin, GABA, and glutamate.
How to work through it
- Study functional brain anatomy focusing on the prefrontal cortex, amygdala, and hippocampus
- Learn the stages of an action potential and synaptic transmission
- Examine how psychoactive substances and endogenous ligands alter synaptic signaling
- Write definitions for neural plasticity and long-term potentiation
- Read evolutionary psychology frameworks and their critics~6hRead
Evolutionary psychology offers powerful distal explanations, but requires rigorous critical thinking to distinguish adaptive traits from non-adaptive byproducts.
You'll learn
- Domain specificity — the hypothesis that the mind consists of specialised, dedicated mechanisms
- Proximate vs distal causation — the difference between immediate physiological triggers and evolutionary origins
- Spandrel — a phenotypic characteristic that evolved as a byproduct rather than a direct adaptive selection
Read Cosmides and Tooby's foundational work on evolutionary psychology (1997, 'Evolutionary Psychology: A Primer') alongside Stephen Jay Gould's critique of evolutionary spandrels and 'just-so stories' (Gould & Lewontin, 1979, Proc. R. Soc. Lond. B).
Done when: you have written a two-page comparative essay outlining when an evolutionary explanation is scientifically falsifiable versus when it is speculative post-hoc storytelling.
How to work through it
- Read Cosmides & Tooby's overview of domain-specific psychological adaptations
- Read Gould & Lewontin (1979) on the spandrels of San Marco
- Note the criteria for demonstrating an evolutionary adaptation in psychology
- Draft the comparative synthesis essay
- Synthesise twin and adoption study methodologies in behavioural genetics~5hSynthesise
Nature vs nurture debates are pervasive; understanding quantitative genetics prevents common deterministic fallacies.
You'll learn
- Heritability — the proportion of phenotypic variance in a population attributable to genetic variance
- Equal environments assumption — the assumption that identical and fraternal twins share environmental similarity equally
Investigate how heritability is calculated using monozygotic vs dizygotic twins reared together and apart. Read Plomin et al.'s core papers on behavioural genetics and analyse why heritability is a population statistic rather than an individual destiny.
Done when: you have written a 400-word explanation of what a heritability estimate of 0.50 actually means mathematically and conceptually.
How to work through it
- Study the classical twin method formula for estimating heritability (Falconer's formula)
- Identify the equal environments assumption and its limitations
- Distinguish between shared and non-shared environmental variance
- Summarise the distinction between genetic influence and genetic determinism
The Behaviourist Tradition and Learning Theory
Explore the historical paradigm of behaviourism, focusing on classical conditioning, operant reinforcement schedules, and the eventual discovery of biological constraints on learning.
- Examine classical and operant conditioning paradigms~5hMethod
Behaviourism provided psychology with rigorous operational methodology and remains the foundation for learning theory and behavioural therapy.
You'll learn
- Operant conditioning — learning where behaviour is controlled by consequences
- Extinction — the gradual weakening of a conditioned response when reinforcement stops
- Shaping — differential reinforcement of successive approximations toward a target behaviour
- Variable ratio schedule — a reinforcement schedule that yields the highest resistance to extinction
Study Ivan Pavlov's work on respondent conditioning and B.F. Skinner's science of operant behaviour. Learn the exact mechanisms of reinforcement schedules (fixed/variable ratio and interval), extinction, spontaneous recovery, and shaping.
Done when: you can correctly classify eight real-world training/behavioural scenarios into their specific operant conditioning quadrant (positive/negative reinforcement, positive/negative punishment) and reinforcement schedule.
How to work through it
- Map the components of classical conditioning (US, UR, CS, CR)
- Diagram Skinner's 2x2 grid of reinforcement and punishment
- Study the cumulative response curves of the four basic intermittent reinforcement schedules
- Document how behavioural shaping operates via successive approximations
- Read primary texts from Watson and Skinner~6hRead
Engaging directly with original behaviourist manifestos reveals the precise philosophical motivations that drove early 20th-century empirical psychology.
You'll learn
- Radical behaviourism — the philosophy that behaviour, including private thought, is subject to natural laws of learning
- Methodological behaviourism — the view that psychology should study only observable behaviour
Read John B. Watson's 1913 manifesto 'Psychology as the Behaviorist Views It' (Psychological Review) and selections from B.F. Skinner's 1953 'Science and Human Behavior'. Note their radical rejection of mentalistic concepts and unobservable states.
Done when: you have annotated both texts and outlined their philosophical commitments to determinism and radical environmentalism.
How to work through it
- Read Watson (1913, Psychological Review)
- Read Skinner (1953, Chapters 1-3)
- Extract Watson's arguments against introspectionism as a scientific method
- Write brief notes on how radical behaviourism defines 'private events' (thoughts and feelings)
- Synthesise the biological limits of behaviourism~5hSynthesise
Understanding how behaviourism was challenged from within empirical biology is essential for seeing how scientific paradigms evolve.
You'll learn
- Equipotentiality principle — the disproven premise that any stimulus can be conditioned to any response equally
- Instinctive drift — the tendency of learned behaviour to revert to innate, species-specific behaviour
- Preparedness — an evolutionary predisposition to learn certain associations more readily than others
Investigate the empirical findings that showed the limits of blank-slate associationism: Garcia and Koelling's (1966) discovery of conditioned taste aversion (the Garcia effect) and Breland & Breland's (1961) 'The Misbehavior of Organisms'.
Done when: you have written a 600-word critique detailing how preparedness and instinctive drift proved that organisms are biologically constrained in what they can learn.
How to work through it
- Read Garcia & Koelling (1966, Psychonomic Science) on taste aversion across long delays
- Read Breland & Breland (1961, American Psychologist) on instinctive drift
- Identify why the Garcia effect violated classical Pavlovian equipotentiality
- Draft the written critique comparing equipotentiality with evolutionary preparedness
Cognitive Psychology and the Information Processing Revolution
Study how psychology transitioned from stimulus-response black boxes to internal representations: memory models, attention, heuristics, and mental computation. This phase builds directly on the limits of behaviourism explored in Phase 3.
- Read Chomsky's review of Skinner and Miller's work on working memory~6hRead
The cognitive revolution redefined psychology as the study of mental information processing; understanding this shift is central to modern psychology.
You'll learn
- Poverty of the stimulus — the assertion that grammar cannot be learned solely from empirical language exposure
- Chunking — grouping individual pieces of information into larger, meaningful units in working memory
Read Noam Chomsky's 1959 review of Skinner's 'Verbal Behavior' (Language), often cited as the catalyst for the cognitive revolution, alongside George A. Miller's 1956 landmark paper 'The Magical Number Seven, Plus or Minus Two' (Psychological Review).
Done when: you have written a 1-page summary explaining why language acquisition and working memory capacity forced psychology to adopt computational and representational models.
How to work through it
- Read Chomsky (1959, Language)
- Read Miller (1956, Psychological Review)
- Summarise Chomsky's poverty of the stimulus argument
- Explain Miller's distinction between bits of information and 'chunks'
- Deconstruct structural and working memory models~6hMethod
Working memory is one of the most rigorously tested constructs in cognitive science and underpins studies of reasoning, attention, and executive function.
You'll learn
- Phonological loop — the component of working memory responsible for verbal and auditory information
- Visuospatial sketchpad — the memory subsystem that handles visual and spatial imagery
- Central executive — the attentional control system coordinating working memory subcomponents
- Dual-task paradigm — a method testing cognitive load by requiring simultaneous performance of two tasks
Examine the Atkinson-Shiffrin multi-store model of memory (sensory, short-term, long-term) and Baddeley and Hitch's (1974) multicomponent working memory model (phonological loop, visuospatial sketchpad, central executive, episodic buffer).
Done when: you can diagram Baddeley's working memory model and describe the experimental evidence (e.g., dual-task interference paradigms) supporting each distinct subcomponent.
How to work through it
- Diagram the Atkinson-Shiffrin model and identify its structural limitations
- Deconstruct Baddeley & Hitch's four-component model of working memory
- Review classic empirical tasks: dual-task paradigms, digit span, and n-back tasks
- Synthesise how working memory interacts with long-term semantic and episodic memory stores
- Read Kahneman and Tversky on heuristics and biases~6hRead
Heuristics and biases research is one of the most widely applied bodies of work in contemporary cognitive and behavioural science.
You'll learn
- Availability heuristic — estimating frequency or probability based on how easily examples come to mind
- Representativeness heuristic — judging probability by similarity to a mental prototype
- Anchoring effect — the disproportionate influence of an initial piece of information on subsequent estimates
Read Amos Tversky and Daniel Kahneman's 1974 Science paper 'Judgment under Uncertainty: Heuristics and Biases'. Examine the mechanics of representativeness, availability, and anchoring, and how they challenge classical economic rationality.
Done when: you have written a 500-word critique detailing how cognitive heuristics serve as functional evolutionary shortcuts while producing systematic, predictable errors in judgment.
How to work through it
- Read Tversky & Kahneman (1974, Science)
- Deconstruct the Conjunction Fallacy (the Linda problem)
- Identify the difference between ecological rationality (Gigerenzer) and bias-focused views
- Draft the written critique on system error vs functional adaptation
Psychodynamic Traditions and the Unconscious
Critically examine psychoanalytic theories, their modern empirical revisions, attachment theory, and the ongoing debate over psychoanalytic testability. Can be worked alongside Phases 2-4.
- Dissect classical Freudian concepts and Popper's falsifiability critique~6hRead
Psychoanalysis has immense cultural and clinical history, but understanding why it was rejected by mainstream experimental psychology is key to scientific demarcation.
You'll learn
- Falsifiability — the principle that a hypothesis must be capable of being proven false by empirical evidence
- Defense mechanism — an unconscious psychological operation functioning to protect an individual from anxiety
- Demarcation problem — the philosophical question of how to distinguish science from non-science
Examine Freud's structural model (Id, Ego, Superego), defense mechanisms, and psychosexual stages. Then read Karl Popper's critique of psychoanalysis as unfalsifiable pseudoscience in 'Conjectures and Refutations' (1963).
Done when: you have written a comparison between an empirically testable psychological hypothesis and an unfalsifiable psychoanalytic claim.
How to work through it
- Outline Freud's topographical and structural models of the mind
- Catalog standard defense mechanisms (projection, sublimation, reaction formation, repression)
- Read Popper's chapter on demarcation and falsification in science
- Draft a 400-word essay on Popper's critique of Freudian case studies
- Trace empirical attachment theory from Bowlby to Ainsworth~6hMethod
Attachment theory represents a successful bridge where psychoanalytic insights were translated into rigorous, observable developmental science.
You'll learn
- Strange Situation — a standardised laboratory procedure for observing attachment relationships in infants
- Internal working model — a cognitive framework of expectations regarding social interactions and relationships
- Attachment security — a state where an infant uses a caregiver as a secure base from which to explore
Investigate how John Bowlby and Mary Ainsworth transformed psychoanalytic concepts of early relational bonds into an empirically testable framework using the Strange Situation Protocol.
Done when: you can describe the four attachment classifications (secure, insecure-avoidant, insecure-resistant, disorganized) and the specific behavioural markers defining each during reunion episodes.
How to work through it
- Read an overview of Bowlby's evolutionary view of maternal deprivation and attachment
- Study Mary Ainsworth's Strange Situation classification methodology (Ainsworth et al., 1978)
- Examine Mary Main's later addition of the disorganized/disoriented attachment classification
- Review longitudinal research on the stability of attachment styles into adulthood
- Synthesise modern cognitive views of implicit processes vs the Freudian unconscious~5hSynthesise
Modern psychology accepts unconscious processes, but defines and measures them through an entirely different conceptual and empirical lens.
You'll learn
- Implicit processing — cognitive operations that occur without conscious awareness or deliberate intent
- Dynamic unconscious — the Freudian concept of active, repressed psychological forces exerting pressure on consciousness
Compare the historical Freudian 'dynamic unconscious' (repressed drives and conflict) with modern cognitive psychology's 'cognitive unconscious' (implicit memory, dual-process automaticity, subliminal priming).
Done when: you have written a 500-word synthesis contrasting how contemporary cognitive neuroscience defines non-conscious processing versus classical psychodynamic theory.
How to work through it
- Review dual-process theories (e.g., System 1 vs System 2)
- Examine empirical paradigms for testing implicit processing (Implicit Association Test, masked priming)
- Compare the energetic/repressive model of mind with modular information-processing architecture
- Write the comparative synthesis paper
Developmental Psychology and the Life Course
Investigate how human cognition, emotion, and morality develop across the lifespan, contrasting continuous vs stage-based models. Runs after basic cognitive and behavioural foundations.
- Compare Piagetian constructivism with Vygotskian sociocultural theory~6hRead
Piaget and Vygotsky represent the two foundational paradigms of developmental psychology: individual exploration versus socially mediated learning.
You'll learn
- Schema — a cognitive structure or mental framework that organises and interprets information
- Assimilation vs Accommodation — fitting new information into existing schemas vs altering schemas in response to new information
- Zone of Proximal Development (ZPD) — the distance between what a learner can do independently and with guidance
- Object permanence — the understanding that objects continue to exist even when they cannot be observed
Examine Jean Piaget's stage theory of cognitive development (sensorimotor, preoperational, concrete operational, formal operational) alongside Lev Vygotsky's sociocultural framework (Zone of Proximal Development, scaffolding, private speech).
Done when: you have created a comparison table contrasting their views on the role of language, social interaction, and domain generality in cognitive maturation.
How to work through it
- Document Piaget's concepts of schema, assimilation, accommodation, and equilibration
- Review Piaget's classic conservation and object permanence tasks
- Study Vygotsky's Zone of Proximal Development (ZPD) and cultural tool mediation
- Construct the detailed comparative table
- Investigate core knowledge and modern infant cognition paradigms~5hMethod
Methodological breakthroughs in infant looking-time paradigms radically shifted developmental science from late-stage constructivism to early core cognition.
You'll learn
- Violation-of-expectation paradigm — a method measuring infants' looking time at impossible vs possible events
- Habituation — a decrease in behavioral response resulting from repeated presentation of a stimulus
- Core knowledge theory — the hypothesis that infants are born with innate, domain-specific conceptual foundations
Read about modern developmental methods that challenged Piagetian timing, focusing on violation-of-expectation looking-time experiments (e.g., Renée Baillargeon's work on infant object permanence and physical reasoning).
Done when: you have written a 400-word explanation of how looking-time methodologies reveal early innate core knowledge that Piaget's motor-dependent tasks failed to detect.
How to work through it
- Study the mechanics of habituation and dishabituation in infant research
- Read Baillargeon (1987, Developmental Psychology) on object permanence in 3.5-month-olds
- Explore Spelke's 'Core Knowledge' systems (objects, agents, number, geometry)
- Draft the written summary on looking-time vs motor-reaching experimental tasks
- Synthesise moral development models from Kohlberg to Haidt~6hSynthesise
Morality research exemplifies modern psychology's transition from pure cognitive developmental stages to affective and evolutionary intuitions.
You'll learn
- Social intuitionist model — the theory that moral judgments are driven primarily by intuitive, emotional responses
- Moral dumbfounding — the phenomenon where people maintain a moral judgment despite being unable to articulate a reason
Trace the study of moral development from Lawrence Kohlberg's rationalistic stage model (pre-conventional, conventional, post-conventional) to Jonathan Haidt's Social Intuitionist Model ('The Emotional Dog and Its Rational Tail', 2001, Psychological Review).
Done when: you have written a 1-page paper explaining whether moral judgments are primarily rational deductions or post-hoc justifications of emotional intuitions.
How to work through it
- Examine Kohlberg's Heinz dilemma and scoring system
- Read Haidt (2001, Psychological Review)
- Analyse Haidt's concept of 'moral dumbfounding'
- Write the synthesis paper contrasting cognitive rationalism with emotional intuitionism
Social Psychology and Situational Forces
Investigate how social contexts, group dynamics, and situational pressures shape individual behaviour, attribution, and judgment.
- Analyze classic social influence experiments and ethical boundaries~6hRead
Classic social psychology produced famous findings, but many suffer from severe methodological criticisms and historical controversies that every researcher must understand.
You'll learn
- Normative social influence — conforming to be accepted or avoid social rejection
- Informational social influence — conforming because one believes others possess accurate knowledge
- Agentic state — a proposed state of mind in which an individual obeys authority without personal responsibility
Examine Solomon Asch's line conformity experiments (1951), Stanley Milgram's obedience studies (1963), and the Stanford Prison Experiment (Haney, Banks, & Zimbardo, 1973). Scrutinise their methodology, demand characteristics, and the resulting modern institutional review board (IRB) ethical standards.
Done when: you have written a critical assessment of the Milgram obedience studies evaluating how agentic state theory compares to alternative explanations like experimenter identification.
How to work through it
- Review Asch's conformity paradigms and variations in confederate unanimous dissent
- Examine Milgram's experimental variations in proximity and authority cues
- Study the ethical aftermath leading to the Belmont Report and informed consent mandates
- Document modern historical and methodological critiques of the Stanford Prison experiment
- Deconstruct cognitive dissonance and attribution theory~6hSynthesise
Cognitive dissonance and attribution errors explain pervasive patterns in political polarisation, consumer behaviour, and interpersonal conflict.
You'll learn
- Cognitive dissonance — psychological discomfort experienced when holding contradictory beliefs or actions
- Fundamental Attribution Error — overemphasising dispositional factors while underestimating situational factors in others' behaviour
- Actor-observer bias — attributing one's own actions to situation but others' actions to character
Read Leon Festinger and J.M. Carlsmith's classic 1959 study 'Cognitive Consequences of Forced Compliance' (Journal of Abnormal and Social Psychology). Study attribution theories (Heider, Kelley) and the Fundamental Attribution Error (Ross, 1977).
Done when: you have documented three distinct real-world case studies demonstrating cognitive dissonance reduction, detailing the belief, the conflicting action, and the specific rationalisation used.
How to work through it
- Read Festinger & Carlsmith (1959)
- Diagram how self-justification occurs under low versus high external incentive
- Study Kelley's Covariation Model of attribution (consensus, distinctiveness, consistency)
- Define the Fundamental Attribution Error / Actor-Observer Bias
- Evaluate intergroup conflict and social identity theory~6hRead
Understanding the conditions under which in-group favouritism and out-group derogation arise is critical to understanding prejudice and social cohesion.
You'll learn
- Realistic Conflict Theory — the proposal that prejudice arises from competition over scarce resources
- Minimal group paradigm — an experimental methodology showing in-group favoritism can occur on arbitrary distinctions
- Superordinate goals — shared goals that necessitate cooperative effort between conflicting groups
Read Muzafer Sherif's Robbers Cave experiment (1954/1961) on Realistic Conflict Theory and Henri Tajfel's Minimal Group Paradigm (1971, European Journal of Social Psychology) establishing Social Identity Theory.
Done when: you have written a 500-word analysis contrasting whether intergroup hostility requires actual competition for scarce resources or simply arbitrary social categorisation.
How to work through it
- Examine the three stages of Sherif's Robbers Cave study (in-group formation, friction, integration via superordinate goals)
- Read Tajfel et al. (1971) on the minimal group paradigm
- Deconstruct social categorisation, social identification, and social comparison
- Write the comparative analysis between Realistic Conflict Theory and Social Identity Theory
Personality, Individual Differences, and Psychometrics
Investigate how stable psychological traits are defined, discovered, and measured through psychometrics, factor analysis, and personality taxonomies.
- Understand factor analysis and psychometric validation~6hMethod
Personality science is mathematically grounded in psychometrics; without understanding factor analysis, personality models look arbitrary.
You'll learn
- Factor analysis — a statistical technique that uncovers underlying latent variables among observed measures
- Latent trait — an unobservable characteristic inferred from a pattern of observable behaviors or test scores
- Cronbach's alpha — a measure of internal consistency reliability among items in a test
- Discriminant validity — empirical evidence that a test does not correlate too strongly with unrelated measures
Study how psychometricians use exploratory and confirmatory factor analysis to reduce hundreds of questionnaire items into latent personality dimensions. Learn the psychometric standards of test-retest reliability, internal consistency (Cronbach's alpha), and convergent/discriminant validity.
Done when: you can interpret a factor loading matrix and explain how latent traits are extracted from inter-item correlation matrices.
How to work through it
- Study the difference between observed variables and latent constructs
- Learn what an eigenvalue and factor loading represent in dimension reduction
- Define Cronbach's alpha and split-half reliability
- Examine how multitrait-multimethod matrices test construct validity
- Read the development of the Five-Factor Model (Big Five)~6hRead
The Five-Factor Model is the gold standard empirical taxonomy of personality in academic psychology.
You'll learn
- Lexical hypothesis — the premise that the most important individual differences become encoded in natural language
- Big Five (OCEAN) — the five broad dimensions of personality identified across diverse cultures and languages
- Continuous trait vs type — viewing traits along a normal distribution versus pigeonholing individuals into discrete categories
Read Costa & McCrae (1992) and Goldberg (1993, American Psychologist) on the lexical hypothesis and the emergence of the Big Five personality traits (Openness, Conscientiousness, Extraversion, Agreeableness, Neuroticism / OCEAN).
Done when: you have written a 1-page summary explaining the lexical hypothesis and how the Big Five model differs conceptually from typological instruments like the Myers-Briggs Type Indicator (MBTI).
How to work through it
- Read Goldberg (1993, American Psychologist)
- Review the lexical hypothesis (Galton, Allport, Cattell)
- Compare continuous trait distributions with categorical personality types
- Document the predictive validity of Big Five traits for health, academic, and relationship outcomes
- Synthesise the Person-Situation debate~5hSynthesise
The Person-Situation debate was a central existential crisis in 20th-century personality psychology that shaped modern interactionist theory.
You'll learn
- Aggregation principle — the principle that trait-behaviour correlations increase substantially when behaviour is averaged across multiple occasions
- Interactionism — the view that behaviour is a joint function of person characteristics and situational constraints
Examine Walter Mischel's 1968 critique ('Personality and Assessment') arguing that personality traits poorly predict behaviour across varying situations (r ≈ .30), and Seymour Epstein's (1979) response demonstrating the power of behavioural aggregation.
Done when: you have written a 500-word essay explaining interactionism: how traits predict aggregated behaviour across time even when individual single-situation predictions remain noisy.
How to work through it
- Review Mischel's (1968) correlation coefficient critique of trait theory
- Study Epstein's (1979, Journal of Personality and Social Psychology) empirical aggregation defense
- Examine modern density distribution approaches to personality states vs traits (Fleeson, 2001)
- Draft the essay explaining interactionism
Clinical Psychology, Psychopathology, and Diagnosis
Examine how mental illness is classified, diagnosed, and treated, critically evaluating the biomedical model, categorical DSM criteria, and alternative dimensional paradigms.
- Critique categorical psychiatric nosology and the DSM system~6hRead
A critical investigator must distinguish between a descriptive diagnostic category and a validated, underlying physiological disease entity.
You'll learn
- Reification — treating an abstract diagnostic label as a concrete, physically discrete disease entity
- Comorbidity — the co-occurrence of two or more distinct clinical disorders in the same individual
- HiTOP — a modern dimensional alternative to categorical psychiatric classification
Study the history and structure of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5). Read classic critiques including Rosenhan's 1973 Science study 'On Being Sane in Insane Places' and Thomas Szasz's 'The Myth of Mental Illness'.
Done when: you have written a 600-word critique detailing the problems of diagnostic comorbidity, high intra-category heterogeneity, and reification in categorical psychiatric nosology.
How to work through it
- Examine the criteria for diagnosing Major Depressive Disorder and Generalised Anxiety Disorder
- Read Rosenhan (1973, Science) and examine subsequent historical critiques
- Identify why two patients with the same DSM diagnosis can share zero identical symptoms
- Investigate alternative dimensional systems like the Hierarchical Taxonomy of Psychopathology (HiTOP)
- Examine the Biopsychosocial Model and Diathesis-Stress frameworks~5hMethod
Modern psychopathology rejects pure nature-versus-nurture explanations in favor of integrative multi-level systems.
You'll learn
- Biopsychosocial model — an approach stating that biological, psychological, and social factors all play a significant role in human functioning
- Diathesis-stress model — a theory explaining disorder as the result of an underlying vulnerability combined with environmental stress
Study George Engel's 1977 Biopsychosocial Model (Science) and the Diathesis-Stress framework. Learn how genetic predispositions, cognitive styles, and environmental stressors interact non-linearly to trigger psychopathology.
Done when: you have mapped out a complete Diathesis-Stress diagram for a specific psychiatric disorder (e.g., depression or schizophrenia) showing predisposing vulnerability, precipitating stressors, and maintaining factors.
How to work through it
- Read Engel (1977, Science) on the need for a new medical model
- Diagram the Diathesis-Stress interaction curve
- Identify predisposing, precipitating, perpetuating, and protective factors (the 4 P's)
- Apply the framework to a clinical case example
- Compare mechanisms of change in evidence-based psychotherapies~6hSynthesise
Evaluating psychotherapies requires understanding both empirical efficacy research and the theoretical models of change they propose.
You'll learn
- Cognitive restructuring — identifying and challenging irrational or maladaptive thoughts
- Therapeutic alliance — the collaborative relationship between therapist and client
- Dodo Bird verdict — the controversial hypothesis that all validated psychotherapies produce roughly equivalent outcomes
Investigate the theoretical foundations and empirical evidence for Cognitive Behavioural Therapy (Beck), Acceptance and Commitment Therapy (Hayes), and Psychodynamic Psychotherapy. Examine the 'Dodo Bird Verdict' debate (common factors vs specific ingredients).
Done when: you have written a 1-page paper detailing whether therapeutic outcome variance is driven primarily by the therapeutic alliance (common factors) or distinct technique-specific mechanisms.
How to work through it
- Examine Aaron Beck's cognitive triad and cognitive restructuring techniques in CBT
- Review third-wave behavioral therapies focusing on psychological flexibility (ACT)
- Read Wampold (2001) on the Common Factors model / Dodo Bird verdict
- Synthesise the evidence comparing specific techniques to non-specific alliance factors
The Replication Crisis, Open Science, and Methodological Reform
Investigate the crisis that shook 21st-century psychology: false-positive psychology, p-hacking, publication bias, large-scale replication projects, and open science reforms.
- Read Simmons et al. on researcher degrees of freedom~6hRead
This paper fundamentally exposed how standard research practices in experimental psychology could produce statistically significant artifacts out of pure noise.
You'll learn
- Researcher degrees of freedom — the flexibility researchers have during data collection, analysis, and reporting
- p-hacking — manipulating data analysis until non-significant results become statistically significant
- HARKing — presenting a post-hoc hypothesis derived from data as if it were an a priori prediction
Read the landmark 2011 paper by Simmons, Nelson, and Simonsohn: 'False-Positive Psychology: Undisclosed Flexibility in Data Collection and Analysis Allows Presenting Anything as Significant' (Psychological Science).
Done when: you have documented the four specific 'researcher degrees of freedom' identified in the paper and how combining them inflates false positive rates above 60%.
How to work through it
- Read Simmons et al. (2011, Psychological Science)
- Define HARKing (Hypothesizing After the Results are Known)
- Analyze p-hacking techniques: optional stopping, flexible covariate selection, dropping conditions
- Summarise the authors' proposed disclosure requirements for authors and reviewers
- Examine the Open Science Collaboration (2015) replication results~6hRead
The 2015 OSC project is the central empirical audit of modern psychology; understanding its methodology and results is mandatory for any serious student.
You'll learn
- Replication — repeating an empirical study to determine whether the original findings can be reproduced
- Publication bias — the tendency of journals to publish only positive, statistically significant findings
- File drawer problem — the suppression of null or non-significant experimental results
Read the Open Science Collaboration's 2015 Science article 'Estimating the Reproducibility of Psychological Science'. Examine the replication rates across cognitive vs social psychology subfields and why effect sizes consistently shrunk by half.
Done when: you have written a 500-word analysis comparing why cognitive psychology experiments replicated at a higher rate (50%) than social psychology experiments (25%) in the 2015 initiative.
How to work through it
- Read Open Science Collaboration (2015, Science)
- Study the metrics used to judge replication success (significance vs effect size comparison)
- Compare the replication rates of cognitive vs social psychology subdisciplines
- Write the comparative analysis discussing context sensitivity and methodological rigor
- Synthesise modern open science reforms and preregistration standards~5hSynthesise
Knowing how psychology is reforming itself equips you to tell whether a contemporary paper meets modern rigorous open-science standards.
You'll learn
- Registered Report — a publishing format where study protocols undergo peer review and receive in-principle acceptance before data collection
- Preregistration — registering a study's hypotheses, design, and analysis plan prior to conducting the experiment
- Confirmatory vs Exploratory research — testing a specific a priori hypothesis versus searching for patterns in data
Investigate the structural solutions adopted by contemporary psychology: Registered Reports, pre-registration of hypotheses on OSF, open data/code mandates, and larger multi-site collaborative labs (e.g., Psychological Science Accelerator).
Done when: you have written a 1-page summary explaining how Registered Reports fundamentally break the link between experimental outcome and publication decision.
How to work through it
- Study the Stage 1 vs Stage 2 peer review model of Registered Reports
- Explore the Open Science Framework (OSF) registry structure
- Examine the distinction between exploratory and confirmatory data analyses
- Draft the summary on how structural journal incentives shape scientific truth
Synthesis: Formulating and Defending a Position
Consolidate your investigation by synthesising conflicting theoretical paradigms and writing a defensible, critical position paper on an unresolved psychological controversy.
- Select an unresolved psychological controversy and build a literature matrix~8hMethod
Synthesising contradictory literature requires a structured method to compare evidence quality rather than simply aggregating opinions.
You'll learn
- Literature matrix — a structured table organising scholarly sources by key themes, methods, and findings
- Constructed emotion theory — Barrett's theory that emotions are situated conceptualisations rather than hardwired universal programs
Choose one major unresolved theoretical debate in psychology (e.g., 'Is the mind modular?', 'Are emotions discrete biological programs or constructed cognitive states?', or 'Is the cognitive chemical imbalance model of depression scientifically defensible?'). Assemble a literature matrix of at least 8 landmark and contemporary papers representing both sides.
Done when: you have an annotated matrix table categorising 8 primary sources by their theoretical allegiance, sample size, methodology, validity threats, and findings.
How to work through it
- Select a sharp, controversial question with substantial literature on opposing sides
- Search psychological databases (e.g., PsycINFO / Google Scholar) for landmark reviews and empirical tests
- Select 4 strong papers defending Position A and 4 defending Position B
- Fill out the matrix using your 10-point methodological rubric from Phase 1
- Draft a structured critical position paper~12hSynthesise
Research that ends in disjointed notes has not finished; articulating and defending a coherent position is the ultimate test of psychological literacy.
You'll learn
- Position paper — a formal written brief that takes a defensible stance on an unresolved topic using empirical evidence
- Falsification criterion — specifying the exact hypothetical evidence that would cause you to change your mind
Write a 2,000-word position paper defending your own evidence-based conclusion on the chosen controversy. Structure it with an introduction to the theoretical impasse, a critique of the empirical methods used by both traditions, a discussion of replication status, and a final defended stance on what the weight of evidence actually demonstrates.
Done when: you have a complete, polished 2,000-word paper with clear section headings, citations of primary literature, and an explicit defense of your thesis.
How to work through it
- Draft the introduction framing the historical and theoretical origin of the debate
- Write Section 1 summarizing and critically appraising the evidence for School A
- Write Section 2 summarizing and critically appraising the evidence for School B
- Write Section 3 evaluating methodological quality, validity threats, and replication history
- Write the conclusion stating your defended position and what empirical finding would falsify it
- Stress-test your position against counter-arguments~4hSynthesise
Defending a view requires actively seeking and answering the strongest possible counter-evidence rather than ignoring dissenting paradigms.
You'll learn
- Steel-manning — constructing the strongest possible version of an opponent's argument before addressing it
- Boundary conditions — the specific parameters under which a psychological theory or finding ceases to apply
Review your position paper against the strongest possible objections from an opposing theoretical school. Write a 500-word addendum addressing the two most potent counter-arguments against your thesis and explaining why your position either survives them or requires boundary conditions.
Done when: you have a written 'Steel-Manned Counter-Arguments' addendum integrated into your final project documentation.
How to work through it
- Identify the two most significant empirical or theoretical vulnerabilities in your argument
- Steel-man both opposing arguments in their most persuasive possible form
- Draft specific responses showing where their critique holds and where your thesis withstands it
- Finalise your complete investigation portfolio
How the plan fits together
11 phases in 4 stages. Anything on the same row can be worked on at the same time.
An arrow points from a phase to the work it unlocks: before starting any phase, every phase with an arrow into it has to be finished first.
Resources
18 in this plan's library, beyond the links on individual tasks.
Books and Academic Primers
Foundational textbooks, histories of psychological thought, and methodological guides.
- Attachment and Loss, Vol. 1: Attachment
Use this foundational work by John Bowlby to understand how ethology and psychoanalytic theory converged into modern empirical attachment theory.
Basic Books · Book · ~£20 · Intermediate
- Behave: The Biology of Humans at Our Best and Worst
Read this comprehensive account to integrate neurobiology, endocrinology, genetics, and evolutionary theory into human behavioral analysis.
Penguin Press · Book · ~£15 · Intermediate
- Diagnostic and Statistical Manual of Mental Disorders (DSM-5-TR)
Use this canonical diagnostic standard to understand categorical classification and evaluate the boundaries between normality and psychopathology.
American Psychiatric Association · Reference Work · ~£130 · Advanced
- MIT 9.00SC Introduction to Psychology
Comprehensive undergraduate course providing the core foundational survey across biological substrates, learning, cognition, development, social forces, psychometrics, and psychopathology.
ocw.mit.edu · MIT OpenCourseWare (Taught by Prof. John Gabrieli) · MIT OpenCourseWare · Completely free (open educational resource; no certificate offered)
- Noba Project Learning Modules
Collection of peer-reviewed textbook modules by leading scientists targeting discrete traditions like evolutionary psychology, psychodynamics, and personality traits.
nobaproject.com · Diener Education Fund · Book · Completely free (open access under CC BY-NC-SA 4.0)
- Psychometrics: An Introduction
Essential textbook for mastering test reliability, construct validity, factor analysis, and scale construction in personality measurement.
SAGE Publications · Book · ~£55 · Intermediate
- Research Methods in Psychology (4th American Edition)
Peer-reviewed open textbook grounding readers in operational definitions, experimental designs, measurement validity, and inferential statistics.
Open Textbook Library / Kwantlen Polytechnic University (Authors: Rajiv S. Jhangiani, Carrie Cuttler, Dana C. Leighton) · Book · Completely free (open access under CC BY-NC-SA 4.0)
- Research Methods in Psychology: Evaluating a World of Information
Essential guide for learning how to critically interrogate claims, understand experimental design, and assess construct and statistical validity.
W. W. Norton & Company · Book · ~£65 · Beginner
- Thinking, Fast and Slow
Provides the definitive synthesis of dual-process theory, cognitive heuristics, and systematic biases in human decision making.
Farrar, Straus and Giroux · Book · ~£12 · Intermediate
Landmark Papers & Archives
Classic empirical studies, major theoretical reviews, and replication registries.
- 'Superstition' in the Pigeon
Read this foundational paper by B.F. Skinner to analyze operant conditioning principles and how reinforcement schedules shape behavioral patterns.
Journal of Experimental Psychology · Paper · Free via academic repositories · Intermediate
- Behavioral Study of Obedience
Read Stanley Milgram's 1963 landmark study to evaluate the power of situational demand characteristics versus dispositional morality.
Journal of Abnormal and Social Psychology · Paper · Free via academic repositories · Intermediate
- Classics in the History of Psychology
Historical primary source repository offering full-text editions of foundational papers and books across behaviourist, cognitive, and psychodynamic paradigms.
psychclassics.yorku.ca · York University (Curated by Christopher D. Green) · Archive · Completely free
- False-Positive Psychology: Undisclosed Flexibility in Data Collection and Analysis Allows Presenting Anything as Significant
Examine this seminal paper by Simmons, Nelson, and Simonsohn to understand researcher degrees of freedom, p-hacking, and false positives.
Psychological Science · Paper · Free via journal open access · Advanced
- The Hierarchical Taxonomy of Psychopathology (HiTOP) Consortium
Open-access publications and measurement tools representing the leading dimensional, empirical alternative to traditional categorical diagnostic manuals.
hitop-system.org · HiTOP Consortium / HiTOP Society · Archive · Completely free open-access literature and clinical materials
- The Magical Number Seven, Plus or Minus Two: Some Limits on Our Capacity for Processing Information
Study George Miller's classic 1956 paper that helped trigger the cognitive revolution by modeling human working memory as an information channel.
Psychological Review · Paper · Free via academic repositories · Intermediate
Research & Open Science Tools
Databases, statistical repositories, and preregistration platforms like OSF.
- AsPredicted
Use this streamlined tool to inspect and generate standardized preregistration plans that limit post-hoc data dredging.
aspredicted.org · Wharton Credibility Lab · Platform · Free · Beginner
- Improving Your Statistical Inferences
Teaches how to avoid false positives, calculate statistical power, understand p-hacking and publication bias, and apply preregistration.
coursera.org · Eindhoven University of Technology on Coursera (Taught by Daniel Lakens) · Online Course · Free to audit all video lectures and readings; paid upgrade available for graded assignments and a certificate
- Open Science Framework (OSF)
Primary platform for exploring live preregistrations, open-access datasets, registered reports, and large-scale replication tracking projects.
osf.io · Center for Open Science (COS) · Research Tool · Completely free for individual researchers to register, search, and store study protocols