How do we define and explain mental health and disorder?
Compare models used to define and explain mental health and mental disorder, including the biopsychosocial model and approaches to classifying normality
Mental health and disorder can be understood through biological, psychological and social lenses. The biopsychosocial model integrates all three, while defining normality itself is contested.
Reviewed by: AI editorial process; not yet individually human-reviewed
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What this dot point is asking
You need to explain how mental health and disorder are defined, compare the models used to explain them, and recognise the difficulty of deciding what is normal.
Defining mental health and disorder
Mental health is a state of wellbeing in which a person realises their abilities, copes with the normal stresses of life, works productively and contributes to their community. It is not simply the absence of illness, but lies on a continuum.
A mental disorder generally involves patterns of thoughts, feelings or behaviours that are distressing, dysfunctional, deviant from social norms, or dangerous (the "four Ds"), and that significantly impair daily functioning.
Approaches to defining normality
Deciding what counts as normal or abnormal is contested. Common criteria include:
- Statistical - behaviour that is rare or far from the average is abnormal. Limitation: rare can be desirable (high intelligence) and common can be unhealthy.
- Social norms - behaviour that violates cultural expectations is abnormal. Limitation: norms vary across cultures and change over time.
- Functional - behaviour that prevents a person coping with daily life is abnormal (maladaptive).
- Distress - behaviour causing significant personal suffering. Limitation: some disorders involve little subjective distress.
Because no single criterion is sufficient, clinicians use a combination.
Models explaining mental disorder
- Biological (medical) model
- Disorders arise from physical causes such as genetics, brain structure, and neurotransmitter imbalances (for example, low serotonin linked to depression). Treatment focuses on medication and physical therapies. Strength: scientific and supports effective drug treatments. Weakness: can ignore life experiences and social context.
- Psychological models
- These emphasise mental processes: psychodynamic (unconscious conflict), behavioural (disorders as learned responses), and cognitive (faulty or unhelpful thinking patterns). Strength: explains the role of experience and thought. Weakness: may underplay biology.
- Social model
- Disorders are shaped by social factors such as poverty, discrimination, relationships, culture and stressful life events. Strength: highlights environment and inequality. Weakness: does not explain individual differences in who develops a disorder.
The biopsychosocial model
The biopsychosocial model integrates all three: biological vulnerability, psychological processes and social circumstances interact to influence mental health. A related idea is the diathesis-stress model, in which a person with an underlying predisposition (diathesis) develops a disorder only when sufficient stress occurs.