AQA · A-Level · Psychology

    Course version: 7182-2025 · Exams from 2027

    The nature-nurture debate: the relative importance of heredity and…

    Full specification wording

    Issues and debates in Psychology: The nature-nurture debate: the relative importance of heredity and environment in determining behaviour; the interactionist approach.

    Nature means inherited influence, nurture means everything experience does, and the argument is over how the two divide up the differences between people.

    Checked against the AQA 7182-2025 specification (opens in a new tab) on .

    • Point 3 of 6
    • 4 key terms

    Study notes

    From the checked teaching notes for this specification point.

    The idea

    Nature means inherited influence, nurture means everything experience does, and the argument is over how the two divide up the differences between people. Psychologists put numbers on it with concordance rates and heritability: intelligence sits near 0.5, which means about half the variation in a population is genetic, not half of any one person's IQ. Schizophrenia concordance runs near 48% for identical twins against 17% for fraternal, so neither side wins outright. The interactionist answer is that the two cannot be separated. Diathesis-stress needs an inherited vulnerability and an environmental trigger, and Tienari's Finnish adoption study found raised risk only where the adoptive family was rated dysfunctional. Epigenetics goes further: Dias and Ressler conditioned mice to fear a scent and saw the fear in pups that had never met it.

    What earns the marks

    • Nature: behaviour is inherited and largely present at birth, the nativist position associated with Descartes.
    • Nurture: behaviour is acquired from the environment, the empiricist position associated with Locke's blank slate.
    • Environment defined broadly, prenatal as well as postnatal, from maternal diet and stress through to peer group and culture.
    • Heritability: a coefficient running from zero to one that describes how much of the variation in a population is genetic, near 0.5 for intelligence.
    • Twin and adoption evidence: concordance is higher for identical than for fraternal twins but never complete, so neither influence is sufficient alone.
    • The interactionist approach: diathesis-stress, an inherited vulnerability expressed only when an environmental trigger arrives (Tienari's adoption data).
    • Epigenetics: experience leaves chemical marks that switch genes on and off, and those marks can carry into the next generation (Dias and Ressler).
    • AO3: the question may be unanswerable as posed, because genes and environment correlate; an inherited temperament shapes the environment a child then receives.
    • AO3: implications are socially sensitive, since strong nature positions have been used to argue for eugenics and strong nurture positions for behaviour shaping.

    Common mistakes and how to put them right

    • Reading a heritability coefficient as a fact about an individual.

      Put it right: Near 0.5 says half the variation in a group is genetic; it says nothing about one person.

    • Claiming twin studies prove nature.

      Put it right: Identical twins share an upbringing as well as their DNA, and concordance is never complete.

    • Leaving the interactionist approach as 'both matter'.

      Put it right: Credit comes from a named mechanism: diathesis-stress, gene-environment correlation or epigenetics.

    • Splitting one person's behaviour into percentages of nature and nurture, which is not what any of the evidence measures.

    Exam tips

    • Pick one behaviour and track it through the whole answer; a schizophrenia thread supplies concordance figures and diathesis-stress in a single move.
    • Top-band answers say why the debate is badly posed, not merely that both sides contribute something.
    • In a stem question, quote the family detail first and label it as a shared gene or a shared environment before you explain anything.

    Try the lesson

    The start of the Issues and debates in Psychology: The nature-nurture debate: the relative importance of heredity and environment in determining behaviour; the interactionist approach. lesson, made from checked teaching notes for this specification point.

    Have a go first

    Which of the following statements best describes the interactionist approach to the nature-nurture debate in psychology?

    Listen

    Nature means inherited influence, nurture means everything experience does, and the argument is over how the two divide up the differences between people. Psychologists put numbers on it with concordance rates and heritability: intelligence sits near 0.5, which means about half the variation in a population is genetic, not half of any one person's IQ. Schizophrenia concordance runs near 48% for identical twins against 17% for fraternal, so neither side wins outright. The interactionist answer is that the two cannot be separated. Diathesis-stress needs an inherited vulnerability and an environmental trigger, and Tienari's Finnish adoption study found raised risk only where the adoptive family was rated dysfunctional. Epigenetics goes further: Dias and Ressler conditioned mice to fear a scent and saw the fear in pups that had never met it. A strong answer earns marks for these points. Nature: behaviour is inherited and largely present at birth, the nativist position associated with Descartes. Nurture: behaviour is acquired from the environment, the empiricist position associated with Locke's blank slate. Environment defined broadly, prenatal as well as postnatal, from maternal diet and stress through to peer group and culture. Heritability: a coefficient running from zero to one that describes how much of the variation in a population is genetic, near 0.5 for intelligence. Exam tip: Pick one behaviour and track it through the whole answer; a schizophrenia thread supplies concordance figures and diathesis-stress in a single move.

    See it

    A top-down flowchart. Two nodes at the top, 'Nature: inherited influence' and 'Nurture: environmental influence', both point down into a central node 'Nature-nurture debate'. From that central node three branches lead down: one to 'Heritability: share of population variation that is genetic', one to 'Twin and adoption evidence: concordance higher for identical than fraternal, never complete', and one to 'Interactionist approach'. The interactionist node then splits into two further nodes: 'Diathesis-stress: inherited vulnerability plus environmental trigger' and 'Epigenetics: experience leaves chemical marks that can carry to next generation'.
    It shows the two sides of the nature-nurture debate feeding into the debate, with heritability, twin and adoption evidence, and the interactionist approach (diathesis-stress and epigenetics) as the routes taken.

    Key words

    Say what each word means before you turn the card.

    heredity and nativism

    Try answering aloud or in your head before turning the card.

    environment and empiricism

    Try answering aloud or in your head before turning the card.

    heritability and concordance rates

    Try answering aloud or in your head before turning the card.

    diathesis-stress and interactionism

    Try answering aloud or in your head before turning the card.

    See every definition
    heredity and nativism
    Behaviour is inherited and largely present at birth, the nativist position associated with Descartes.
    environment and empiricism
    Behaviour is acquired from the environment, the empiricist position associated with Locke's blank slate.
    heritability and concordance rates
    A coefficient from zero to one describing how much of the variation in a population is genetic, near 0.5 for intelligence, with concordance higher for identical than fraternal twins but never complete.
    diathesis-stress and interactionism
    An inherited vulnerability expressed only when an environmental trigger arrives, as in Tienari's adoption data.

    Label the diagram

    Some boxes have lost their names. Pick the right name for each number.

    The diagram again, with 3 boxes numbered instead of named. A top-down flowchart. Two nodes at the top, 'Nature: inherited influence' and 'Nurture: environmental influence', both point down into a central node 'Nature-nurture debate'. From that central node three branches lead down: one to 'Heritability: share of population variation that is genetic', one to 'Twin and adoption evidence: concordance higher for identical than fraternal, never complete', and one to 'Interactionist approach'. The interactionist node then splits into two further nodes: 'Diathesis-stress: inherited vulnerability plus environmental trigger' and 'Epigenetics: experience leaves chemical marks that can carry to next generation'.
    • 1Box 1

    • 2Box 2

    • 3Box 3

    0 of 3 labelled

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