IB Psychology: Complete Guide to the Course (SL & HL)

By Michael Thompson · Education Specialist; 10 years teaching the IB at Bromsgrove School · Published 21 May 2026 · Updated 12 June 2026

IB Psychology is a two-year Diploma Programme course that asks students to examine human behaviour through three lenses - biological, cognitive, and sociocultural - and then apply that understanding in written exams and a hands-on internal assessment. At Standard Level, you sit two exam papers; at Higher Level, you add a third paper on qualitative research methods and choose from four specialist option topics. The course is popular with students heading towards psychology, medicine, social work, or any field where understanding behaviour matters. This guide covers the full syllabus structure, what each paper demands, how the Internal Assessment works, and what UK universities typically expect from IB applicants.

Key Takeaways

• Three core approaches: Biological, cognitive, and sociocultural - every Paper 1 question draws from one of these frameworks.
• Paper 3 is HL only: Higher Level students sit an additional paper on qualitative research methods, based on an unseen stimulus text.
• The Internal Assessment replicates a published study: You design and run an experimental study based on an existing piece of research, write it up in 2,200 words, and it counts towards your final grade.
• Four HL option topics: Abnormal psychology, developmental psychology, health psychology, and human relationships - you study one in depth for Paper 2.
• Ethics appear across all papers: Ethical considerations (informed consent, confidentiality, right to withdraw) can be examined in any Paper 1 or Paper 2 question.
• UK university entry varies: A typical psychology degree entry at a UK university requires around 30-32 IB points, with a 5 or 6 at HL in a relevant subject.

In This Article

1. What Is IB Psychology
2. The Three Approaches: Biological, Cognitive, and Sociocultural
3. Paper 1: The Approaches in Psychology
4. Paper 2: The HL Options in Psychology
5. Paper 3: Qualitative Research Methods (HL Only)
6. The Internal Assessment: Replicating a Published Study
7. Ethical Guidelines and How They Appear in Exams
8. IB Psychology Units and How to Study Them
9. Psychology University Requirements: What UK Admissions Look For
10. Where to Go From Here

1. What Is IB Psychology

IB Psychology is a Group 3 subject in the IB Diploma Programme, sitting within the Individuals and Societies category alongside subjects like Economics and History. It introduces students to three core approaches for understanding human behaviour: biological, cognitive, and sociocultural. The content is the same at both Standard Level and Higher Level, but the two tiers diverge in scope. HL students study one of four optional themes in greater depth and sit a third exam paper on qualitative research methods, neither of which appears at SL.

One detail that catches students off guard: because SL and HL share the same core, an SL student who changes their mind mid-course can, in principle, move to HL without restarting. The practical barrier is time, not content.

Students tend to choose the subject for three reasons:

• Medicine and health science pathways - the biological approach covers topics such as neuroplasticity and the role of hormones in behaviour, which maps onto pre-medicine reading.
• Social science and humanities - the sociocultural approach examines how culture, group dynamics, and social norms shape thought and action, which complements subjects like History or Geography.
• Personal relevance - psychology addresses questions about memory, emotion, and identity that many students are already curious about before they walk into the classroom.

The non-obvious trade-off at SL is that, while the workload is lighter, the exam questions demand the same depth of evaluative argument. Fewer papers does not mean simpler thinking.

2. The Three Approaches: Biological, Cognitive, and Sociocultural

IB Psychology organises its core content around three approaches to explaining human behaviour. Each one asks a different question: is this behaviour rooted in biology, in how we think, or in the social world we inhabit? Paper 1 tests all three, so understanding how they differ is the foundation of everything else.

The Biological Approach

The biological approach treats behaviour as the product of physiology. The four main areas are genetics (inherited traits and twin studies), hormones (such as cortisol and testosterone), neurotransmitters (dopamine, serotonin), and brain localisation (specific regions linked to specific functions).

The non-obvious gotcha here: the IB does not reward you for naming a study alone. Examiners want you to explain how the study supports the biological explanation, then evaluate its methodology. A student who names a twin study but cannot link heritability estimates to the claim being made will lose marks at both SL and HL.

The Cognitive Level of Analysis

The cognitive level of analysis (sometimes called the cognitive approach in newer IB terminology) focuses on internal mental processes: how people encode, store, and retrieve information, and how mental shortcuts distort judgement.

Key concepts include:

• Schemas - mental frameworks that filter new information through existing knowledge
• Memory models - multi-store and working memory models that explain how information is processed
• Cognitive biases - systematic errors such as the misinformation effect or reconstructive memory

The productive tension in this approach is that it uses controlled lab experiments to study processes that are inherently unobservable, which gives examiners a ready-made evaluation point about ecological validity.

The Sociocultural Level of Analysis

The sociocultural level of analysis examines how culture, group membership, and social norms shape behaviour. Core topics include social identity theory, conformity, norms, and acculturation (the process of adapting to a new cultural environment).

A useful framing: where the biological approach asks "what is the mechanism inside the person?", the sociocultural approach asks "what is the mechanism in the group?"

How All Three Appear in Paper 1

Paper 1 is split into Section A and Section B:

The ERQ in Section B is where the three approaches create a genuine strategic choice. HL students write longer, more evaluative essays than SL students on the same prompt, so the approach you know most deeply should be your default pick.

3. Paper 1: The Approaches in Psychology

Paper 1 covers the three core approaches - biological, cognitive, and sociocultural - and is sat by both SL and HL students. It is divided into two sections with different demands on time and depth.

Section A presents three short-answer questions (SAQs), one per approach. You answer two of them. Each SAQ is worth 9 marks, and the command terms are typically "describe" or "explain". "Describe" asks you to give an account of a study or concept without commentary. "Explain" asks you to show how or why something works, which means mechanism, not just definition. You have roughly 20 minutes per SAQ if you budget your time sensibly.

Section B is a single extended-response question (ERQ), worth 22 marks, drawn from any of the three approaches. The command terms here are "evaluate" and "discuss". "Evaluate" requires you to make a judgment, with evidence on both sides leading to a reasoned conclusion. "Discuss" is broader and expects consideration of different perspectives without necessarily reaching a verdict. The distinction matters because examiners mark against markbands, and an answer that describes where it should evaluate will not reach the top band regardless of how much content it contains.

The non-obvious gotcha: ethical considerations can appear in both sections, not just the ERQ. An SAQ might ask you to "explain one ethical consideration in research" using a specific approach. Students who treat ethics as a Paper 1 footnote rather than a core thread of the biological, cognitive, and sociocultural level of analysis will be caught out.

A quick reference for Section A command terms:

For the ERQ, choose the approach where you can mount the strongest argument, not simply the one you revised most recently.

4. Paper 2: The HL Options in Psychology

Paper 2 is where the course splits. Every student studies one of four options in depth, and the exam asks you to write extended response questions (ERQs) drawing on that option's research. SL students write one ERQ; HL students write two, both from their chosen option.

The four options are:

• Abnormal psychology - diagnosis and classification (including debates around the DSM and ICD), explanations of disorders, treatment approaches, and cultural considerations around what counts as "abnormal" in the first place.
• Developmental psychology - cognitive and social development across the lifespan, the role of attachment, and how research methods in this area must account for studying children ethically.
• Health psychology - models of health behaviour, stress and its physiological effects, substance misuse, and interventions aimed at changing behaviour.
• Human relationships - personal relationships, group dynamics, social responsibility, and the psychology of conflict and conflict resolution.

One non-obvious trade-off worth knowing: HL students writing two ERQs from a single option are rewarded for breadth within that option, not just depth. A student who has only revised two or three studies tightly risks running out of material on the second question. Spreading revision across the full option is not optional.

In practice, the option your school teaches is almost always determined by your teacher's research background, not a menu you pick from yourself. A teacher whose training focused on clinical psychology will typically deliver abnormal psychology more confidently, and that usually shows in student outcomes. If your school offers a genuine choice, weigh personal interest against the quality of available resources: a topic you find fascinating but have thin notes on is harder to navigate under timed conditions than a topic you find moderately interesting but know well.

5. Paper 3: Qualitative Research Methods (HL Only)

Paper 3 is exclusive to Higher Level candidates. You receive an unseen extract from a real published qualitative study and must answer three structured questions on it, all within 60 minutes. The extract is given to you cold: no prior knowledge of that specific study is expected or useful.

The three questions follow a fixed pattern:

• Question 1 targets reflexivity, asking you to explain how researcher bias or positionality could affect the study's findings.
• Question 2 targets sampling, asking you to discuss the method used to select participants and its limitations.
• Question 3 targets credibility or triangulation, asking you to evaluate how the researchers established trustworthiness in their findings.

The qualitative methods you may encounter in the extract include interviews, case studies, naturalistic observations, and thematic analysis. You do not choose which appears; the paper sets it.

The non-obvious gotcha here: many candidates treat Paper 3 like a methods theory test and write pre-prepared definitions without anchoring their answers to the actual extract. The mark scheme rewards application. Every point you make about reflexivity, sampling, or credibility must be tied to something specific in the text in front of you. A technically correct definition of purposive sampling earns little if you never connect it to how the researchers in that particular extract actually recruited participants.

A practical approach under exam conditions: read the extract once for sense, then read each question before rereading the extract specifically hunting for evidence. Annotate as you go. Write answers in clear prose, not bullet points, since the IB mark scheme for Paper 3 is criterion-referenced and rewards coherent argument over listed points.

6. The Internal Assessment: Replicating a Published Study

The IB Psychology Internal Assessment is not original research. You are asked to replicate an existing published study, adapting its method closely enough that your results can be compared to the original findings. That distinction matters: examiners are not looking for novelty, they are looking for methodological precision and clear psychological reasoning.

The report has a strict structure across four sections:

• Introduction - identify the original study, state your aim and hypothesis, and explain the theoretical rationale
• Exploration - detail your design, participants, materials, and procedure
• Analysis - present descriptive statistics and interpret your results
• Evaluation - discuss the strengths and limitations of your replication, with reference to the original

The word limit is approximately 2,200 words. This is tighter than it sounds. Students often spend too many words describing the original study in the introduction and then run short in the evaluation, which carries significant marks. Aim to keep the introduction under 500 words and use the space you save in the evaluation.

Common studies students replicate include Stroop's 1935 interference task (response time under congruent versus incongruent conditions), the Loftus and Palmer misinformation paradigm, and variations on the Müller-Lyer illusion. Cognitive bias and memory experiments dominate because they require no specialist equipment, can be run on classmates with minimal risk, and produce quantitative data that is straightforward to analyse with descriptive statistics.

The ethical requirements are non-negotiable. Every participant must sign an informed consent form before the study begins, receive a debrief explaining the true purpose afterwards, and be told explicitly that they have the right to withdraw their data at any point. Your exploration section must document all three. Missing any one of them is a criterion-level deduction, not a minor error.

One counter-intuitive trade-off: choosing a study with results that are very easy to replicate can actually weaken your evaluation. If your findings match the original almost exactly, you have little to analyse in terms of confounding variables or methodological differences. A partial replication, where results diverge somewhat from the original, gives you richer material for the evaluation section.

The IA is worth 20% of your final IB Psychology grade, making it the same weight as Paper 3 for HL students. Starting the ethical approval process early within your school is the single most time-sensitive step, as many schools require a supervisor sign-off before any data collection begins.

7. Ethical Guidelines and How They Appear in Exams

Ethics is not a standalone topic in IB Psychology - it runs through every approach and every paper. Examiners expect you to weave ethical analysis into study evaluations, not save it for a separate paragraph at the end.

The five core principles you need to know:

• Informed consent - participants must understand what they are agreeing to before the study begins.
• Confidentiality - personal data must not be identifiable in published findings.
• Right to withdraw - participants can leave at any point without penalty.
• Protection from harm - no lasting physical or psychological damage should result from participation.
• Debrief - participants are told the true aim of the study after it concludes, especially when deception was used.

Exam questions typically frame ethics as "discuss the ethical considerations of [study or method]" or "evaluate the use of animals in research." The second phrasing is a specific flashpoint. The IB expects you to acknowledge why animal research is sometimes necessary (species where certain procedures cannot ethically involve humans, controlled genetic conditions) and then weigh that against the principle of protection from harm, the question of whether findings generalise to humans, and whether the procedures met guidelines such as minimising suffering and using the smallest viable sample size.

The non-obvious gotcha: debrief does not erase all ethical problems. Students frequently argue that debriefing "solves" the issue of deception. Examiners will credit the stronger position: debrief mitigates but does not eliminate harm, particularly in studies where psychological distress occurred during the procedure itself.

Practical rule: every ethical point you raise must be tied to a named study. Arguing that informed consent was problematic in the abstract earns limited credit. Arguing that Milgram's obedience research raised informed consent concerns because participants were deceived about the true purpose, and that subsequent distress raised protection from harm issues, earns full marks at the evaluation level.

8. IB Psychology Units and How to Study Them

Revision for IB psychology works best when you treat the course as four parallel blocks: the biological approach, the cognitive approach, the sociocultural approach, and your chosen HL option (if applicable). Each block has its own content points, and each content point needs its own study.

Build a study bank before you touch a past paper. For every content point, record the study in a consistent format:

• Study name and researcher (e.g., Baddeley on the working memory model)
• Method (lab experiment, case study, interview, etc.)
• Key findings (one or two precise sentences)
• Evaluation (at least one strength and one limitation)
• Ethical angle (which guideline applies and how)

The non-obvious trap here is that students often learn one flagship study per topic and stop. Examiners writing SAQs can ask for "one study" or "a study" - but ERQs reward breadth. Aim for two studies per content point minimum.

Once your bank is complete, practise with past papers using command terms as your guide. "Describe" (SAQ) requires a factual summary; "discuss" or "evaluate" (ERQ) requires argument and counter-argument. These are not interchangeable, and confusing them is one of the most common sources of lost marks.

Class practicals - short replication activities your teacher runs in lessons - are worth revisiting before the IA and Paper 3. They give you a concrete reference point for understanding ethical procedures and research design from direct experience, not just memorised definitions.

9. Psychology University Requirements: What UK Admissions Look For

Most UK psychology degrees do not require IB Psychology HL as a named subject, but taking it at HL signals genuine subject knowledge at a point in the application cycle when personal statements need to be specific.

**IB points requirements** vary by institution and selectivity. As a concrete reference point, City St George's University of London sets its BSc Psychology entry requirement at 30 IB points, with a minimum grade of 5 in three HL subjects and a minimum grade of 5 in both SL Maths and SL English. The Maths and English floor is the detail that catches students out: you can hit the overall points target and still fall short if those two subjects come in below 5.

More selective universities typically sit above 35 points, with specific HL requirements that often favour sciences or mathematics. Check each university's own UCAS entry page rather than relying on aggregated comparison sites, which can lag behind annual updates.

Where IB Psychology feeds your application directly:

• The Internal Assessment gives you a real piece of empirical research to discuss in a personal statement, including methodology choices and ethical considerations you had to navigate.
• Paper 3 (HL only) trains you in qualitative analysis, a topic that appears in most university Year 1 research methods modules.
• Specific study knowledge from the biological, cognitive, and sociocultural approaches shows admissions tutors you already understand the field's core divisions, rather than knowing psychology only from general reading.

The non-obvious trade-off: taking Biology at HL alongside Psychology HL tends to strengthen applications to programmes with a neuroscience or clinical pathway, since many universities weight scientific literacy more heavily than prior psychology knowledge.

10. Where to Go From Here

Download the current IB Psychology subject guide from the IBO website this week, then open your teacher's scheme of work alongside it and map each content point one-to-one. The non-obvious gotcha: the guide specifies which studies are mandatory and which are illustrative examples, and teachers sometimes teach an illustrative study as if it were required. Knowing the difference before your first mock saves you from over-revising the wrong material.

Once you have the guide mapped:

• **Past paper practice** - work through Paper 1 questions in timed conditions, rotating across all three approaches so you do not accidentally neglect the sociocultural or biological sections.
• IA planning - set an internal deadline for your replication proposal at least six weeks before your school's submission date. That buffer absorbs ethics-committee feedback.

Check the IBO website for the current subject guide, and confirm your school's IA deadlines with your IB coordinator before the end of this week.

FAQ

Is IB Psychology easy?

IB Psychology is content-heavy rather than mathematically complex - success depends on memorising named studies and applying them precisely to command-term questions, which rewards disciplined revision over raw ability.

How long is IB Psychology Paper 1?

Paper 1 runs for two hours and covers the three core approaches through short-answer questions in Section A and one extended response question in Section B.

How long is IB Psychology Paper 2?

Paper 2 also runs for two hours; SL students answer one ERQ and HL students answer two ERQs, both drawn from their chosen option topic.

How long is IB Psychology Paper 3?

Paper 3 (HL only) runs for one hour and requires students to answer three questions about an unseen qualitative research study.

What does IB Psychology cover?

The course covers three approaches to understanding behaviour (biological, cognitive, sociocultural), one of four option topics (abnormal, developmental, health, or human relationships), qualitative research methods at HL, and an experimental internal assessment.

How do you write an IB Psychology ERQ?

An ERQ (extended response question) requires you to address the command term directly - usually 'evaluate' or 'discuss' - by presenting named studies as evidence, acknowledging limitations, and integrating ethical or methodological considerations throughout.

References

• DP Subject: Individuals and Societies - 2025-2026 Catalogue - https://catalogue.ibo.org/en/professional-development/dp-subject-individuals-and-societies
• Psychology | City St George's, University of London | UCAS - https://www.ucas.com/explore/courses/f66de983-36b3-8d4e-7e47-7e2d8d1b3062/course