What Are The Six Concepts In IB Psychology? The Short Answer

The new IB Psychology syllabus (first assessment 2027) introduces six key concepts that help us think more deeply about human behaviour and psychological research.

The six concepts are:

  1. Bias – How our thinking, experiences or preferences might influence behaviour, research and conclusions.
  2. Causality – Whether one factor actually causes a change in another, rather than simply being associated with it.
  3. Change – How and why behaviour, thinking and psychological processes develop or change over time.
  4. Measurement – How psychologists measure psychological characteristics, experiences and behaviour, and whether those measurements are accurate and meaningful.
  5. Perspective – How different approaches, viewpoints and experiences influence our understanding of behaviour.
  6. Responsibility – The ethical and professional obligations involved in psychological research and the application of psychological knowledge.


These concepts are not separate topics that you simply need to memorise.

Instead, they are different ways of thinking about the psychology you are learning.

You will use them throughout the course, particularly in Paper 1 Section C and Paper 2 Section B.

What Are The Six Concepts In IB Psychology? The Long Answer

One of the most important changes to the new IB Psychology syllabus is the introduction of six concepts.

You might be wondering why we need them. Surely there are already enough theories, research methods and psychological terms to learn?

Well, the concepts are designed to help you make connections between different areas of psychology and develop a deeper understanding of behaviour.

For example, imagine you are learning about social learning theory.

You might understand how people learn behaviour through observing and imitating others.

But what happens when we start asking questions about that explanation?

  • Does observing a role model actually cause someone to imitate their behaviour?
  • How might social learning explain changes in behaviour over time?
  • Are there other perspectives that could explain the same behaviour?
  • How could we measure whether observational learning has occurred?


Notice how the concepts encourage us to think beyond simply describing a theory?

This is exactly what the IB wants you to develop: the ability to question, analyse and critically evaluate psychological knowledge.

Let's explore each concept in more detail.

1. Bias

Bias refers to influences that can limit objective thinking or lead to systematic distortions in how we perceive, interpret or investigate information.

Bias can occur in our everyday thinking, but it can also influence psychological research.

For example, confirmation bias occurs when people favour information that supports their existing beliefs.

Imagine someone believes that teenagers are irresponsible. They might notice occasions when teenagers behave irresponsibly but overlook examples of responsible behaviour.

Their existing belief influences how they interpret what they observe.

Bias can also occur during psychological research.

For example, a researcher conducting interviews might unintentionally ask leading questions that encourage participants to respond in a particular way.

Questions to ask yourself:

  • Could someone's expectations or experiences influence their behaviour?
  • Could the researcher's beliefs affect how the study is conducted or interpreted?
  • What could be done to reduce bias?


Remember: Bias isn't just about prejudices or stereotypes. It can influence how people think, how research is conducted and how psychological explanations are developed.

2. Causality

Causality is concerned with whether one factor causes another.

Psychologists are often interested in explaining why behaviour occurs, but establishing cause and effect can be difficult.

For example, imagine research finds that students who spend more time on social media report lower levels of wellbeing.

Does this mean social media use causes poorer wellbeing?

Not necessarily.

It could be that students experiencing poorer wellbeing spend more time on social media.

Alternatively, another factor, such as loneliness, might influence both.

This is why psychologists distinguish between correlation and causation.

Experimental research can provide stronger evidence for causal relationships, particularly when researchers manipulate an independent variable and control extraneous variables.

However, even experiments have limitations.

Questions to ask yourself:

  • Does the evidence demonstrate a causal relationship or simply an association?
  • Could other variables explain the findings?
  • How confidently can we conclude that one factor causes another?


Remember: Just because two variables are related doesn't mean one causes the other.

3. Change

Change focuses on how psychological processes, experiences and behaviour develop or alter over time.

Some changes occur naturally as we grow and develop, while others happen because of learning, experience, environmental influences or interventions.

For example, neuroplasticity refers to the brain's ability to change and reorganise in response to experience, learning or damage.

Imagine someone suffers a brain injury that affects their ability to speak.

Over time, with rehabilitation and speech therapy, they may regain some language abilities as the brain adapts.

This illustrates how biological changes can contribute to changes in behaviour.

Change is also relevant to other areas of psychology.

For example, psychologists might investigate how attitudes change, how relationships develop or how treatment can reduce symptoms of psychological disorders.

Questions to ask yourself:

  • What factors might cause behaviour to change?
  • Are these changes temporary or long-lasting?
  • How can psychological theories explain the changes we observe?


Remember: Change isn't just about human development. It can occur in our brains, thinking, emotions, relationships and behaviour throughout life.

4. Measurement

Measurement concerns how psychologists investigate and quantify psychological characteristics, processes and behaviour.

Unlike some sciences, psychology often investigates things we cannot directly observe.

For example, how do you measure happiness?

You cannot simply look inside someone's mind and see how happy they are.

Instead, psychologists might use questionnaires, interviews or behavioural observations.

However, each method has strengths and limitations.

Imagine researchers use a questionnaire to measure stress levels.

Participants might interpret questions differently or give socially desirable answers.

This raises questions about the validity and reliability of the measurement.

  • Validity concerns whether a measure actually measures what it claims to measure.
  • Reliability concerns whether the measurement produces consistent results.


Questions to ask yourself:

  • How has the psychologist measured the behaviour or psychological characteristic?
  • Is the measurement valid and reliable?
  • Could a different measurement method produce different findings?


Remember: Just because something has been measured doesn't mean it has been measured accurately.

5. Perspective

Perspective focuses on how different viewpoints, assumptions and explanations influence our understanding of behaviour.

Psychology is particularly interesting because the same behaviour can often be explained in several ways.

For example, consider depression.

A biological perspective might focus on genetic influences, neurotransmission or brain functioning.

A cognitive perspective might investigate how negative thinking patterns contribute to depression.

A sociocultural perspective might examine the influence of relationships, social support or cultural expectations.

Each perspective provides a different way of understanding the same psychological experience.

This raises an important question: Can one perspective fully explain complex human behaviour?

Often, combining different perspectives provides a more comprehensive explanation.

Perspective can also involve recognising how cultural and individual viewpoints influence the way psychological knowledge is developed and interpreted.

Questions to ask yourself:

  • How might different psychological approaches explain the same behaviour?
  • What does each perspective help us understand?
  • What might be overlooked by relying on just one perspective?


Remember: Different perspectives are not necessarily competing explanations. They can complement one another.

6. Responsibility

Responsibility concerns the ethical obligations of psychologists and the consequences of conducting and applying psychological research.

Psychologists have a responsibility to protect research participants and consider how their findings might affect individuals and society.

For example, imagine researchers want to investigate the effects of sleep deprivation on cognitive performance.

They must consider whether deliberately reducing participants' sleep could cause harm.

They would also need to consider informed consent, confidentiality and the right to withdraw.

However, responsibility goes beyond research ethics.

Psychologists also need to consider how psychological knowledge is communicated and applied.

For example, research findings about differences between groups could be misinterpreted or used to reinforce stereotypes.

Psychologists therefore have a responsibility to communicate findings carefully and avoid making claims that go beyond the evidence.

Questions to ask yourself:

  • What ethical issues arise from this research?
  • How can psychologists protect participants?
  • What responsibilities do psychologists have when interpreting and applying their findings?


Remember: Responsibility isn't just about following ethical guidelines. It also involves considering the wider consequences of psychological knowledge.

How Are The Six Concepts Assessed In IB Psychology?

Understanding these concepts is particularly important for two examination sections.

Paper 1 Section C

In Paper 1 Section C, you answer a 15-mark concept-based extended response question.

The question will connect a concept to an area of psychology within one of the four contexts:

  • Health and wellbeing
  • Human development
  • Human relationships
  • Learning and cognition


For example, imagine you were asked to discuss the concept of causality in relation to the effects of social media on wellbeing.

You would need to go beyond describing research on social media.

You might consider whether research demonstrates causal relationships, whether other variables could explain the findings and how confidently conclusions can be drawn.

Your discussion should remain focused on the concept and how it relates to the psychology in the question.

An important point to remember is that any of the six concepts could be connected to any area of study in the examination.

This doesn't mean you need to memorise every possible combination!

Instead, you should develop enough understanding to apply the concepts flexibly, including to questions you haven't encountered before.

You can read more in my IB Psychology Paper 1 Guide.

Paper 2 Section B

Paper 2 Section B is also worth 15 marks, but the task is different.

You are given an unfamiliar psychological research study and asked to evaluate it using two or more concepts.

For example, you might consider:

  • Bias: Could the sampling method or researcher's expectations have influenced the findings?
  • Causality: Does the research design allow causal conclusions?
  • Measurement: How accurately were the variables measured?
  • Responsibility: Were appropriate ethical safeguards used?


The concepts you discuss should help you critically evaluate the specific research provided.

Don't simply define each concept and list generic strengths and limitations.

You need to explain how the concepts relate to the research and why they matter when interpreting the findings.

You can read more in my IB Psychology Paper 2 Guide.

What's The Best Way To Learn The Six Concepts?

My advice is to avoid treating the concepts as another list of definitions to memorise.

Instead, try connecting them to topics you are already studying.

For example, if you are learning about conformity, ask yourself:

  • Bias: Could participants' responses be influenced by social desirability?
  • Causality: Can we establish that group pressure causes conformity?
  • Change: How might conformity change as group size increases?
  • Measurement: How could conformity be measured?
  • Perspective: How might cognitive and sociocultural explanations differ?
  • Responsibility: What ethical concerns might arise when investigating conformity?


You don't need to make connections with all six concepts for every topic.

In fact, some concepts will be much more relevant than others.

The important thing is to recognise meaningful connections and develop your ability to explain them.

Another useful strategy is to practise answering questions that begin with:

How? Why? To what extent? What are the implications?

These encourage you to think beyond description and develop the analytical skills required in extended responses.

My Final Advice

The six concepts might seem like an additional challenge when you first start studying IB Psychology.

However, I think they actually provide a useful way of organising your thinking.

Rather than seeing psychological theories and research studies as separate things to learn, the concepts help you make connections and develop a more complete understanding of psychology.

And that is exactly what will help you when answering unfamiliar examination questions.

Remember: Don't just learn what the six concepts mean. Learn how to use them to question, explain and evaluate psychology.

That's what makes conceptual understanding so valuable!

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