In simple terms
A friendly intro before the formal notes — no formulas yet.
Fixing the problem vs. proving you fixed it
Treating a disorder has two halves. The first is choosing a treatment that matches a proposed cause. The second — the one students forget — is proving the treatment, and not something else, is what made the person better. Most of the marks live in that second half.
Imagine someone recovers from a bad cold a week after starting a herbal tea. Did the tea cure them, or would they have recovered anyway? Maybe they got better simply because they believed the tea would work (placebo), or because colds pass on their own (spontaneous remission). Treating depression raises exactly the same problem: people improve for many reasons at once, so showing that the SSRI or the therapy caused the improvement requires careful control groups, not just a happy patient.
- 1
Pick a treatment and link it to a proposed cause of MDD (e.g. SSRIs to the serotonin hypothesis; CBT to Beck's negative schemas).
- 2
Support it with a named study or meta-analysis — state aim, procedure and findings.
- 3
Evaluate effectiveness AND the difficulty of measuring it: relapse, placebo, spontaneous remission, individual differences, culture.
- 4
Weigh the interactionist option: combining biological and psychological treatment often outperforms either alone.
Explore the concept
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Full topic notes
Formal explanation with the rigour you need for the exam.
The disorder and the etiology–treatment link
Major depressive disorder involves persistent low mood, loss of interest or pleasure (anhedonia), disturbed sleep and appetite, fatigue, feelings of worthlessness and, in severe cases, suicidal ideation, lasting at least two weeks. The golden rule for treatment questions is that every treatment should be linked to a proposed CAUSE. Biological treatments assume a physical cause (low serotonin activity); cognitive treatments assume a cognitive cause (negative schemas); sociocultural treatments assume that isolation and social context maintain the disorder. Match treatment to etiology and your knowledge marks look deliberate rather than accidental.
Biological treatment: SSRIs
The biological approach treats MDD as an illness with a physical basis. The most common biological treatment is drug therapy with Selective Serotonin Reuptake Inhibitors (SSRIs), such as fluoxetine (Prozac). These match the serotonin hypothesis of depression — the theory that reduced serotonin activity contributes to low mood.
Mechanism: After a neuron releases serotonin into the synapse, a reuptake transporter normally pumps it back into the presynaptic neuron. SSRIs block that transporter, so serotonin lingers in the synapse and binds more to postsynaptic receptors. They raise serotonin AVAILABILITY — a common exam error is writing that they 'produce more serotonin'.
Onset: Symptom relief typically takes 2–6 weeks, even though the chemical effect is immediate — a puzzle for the simple serotonin story.
Effectiveness: Reliable for moderate-to-severe MDD; benefit over placebo is small for mild depression (Kirsch et al., 2008).
Side-effects: Nausea, insomnia, agitation, sexual dysfunction; a boxed warning about increased suicidal ideation in adolescents.
Relapse: High once medication stops, because the drug treats symptoms, not the thinking patterns or life circumstances behind them.
Cognitive/psychological treatment: CBT
Cognitive Behavioural Therapy matches a cognitive etiology: Beck argued that depression is maintained by negative SCHEMAS organised into a negative cognitive triad — negative beliefs about the self ('I am worthless'), the world ('everything is against me') and the future ('nothing will get better'). These schemas generate biased, automatic negative thoughts that keep mood low. CBT's core move is to make those beliefs explicit, treat them as hypotheses rather than facts, and test them against evidence (cognitive restructuring), alongside behavioural activation — scheduling rewarding activity to break the withdrawal–low-mood cycle.
Target: Cognitions and behaviours — NOT brain chemistry. This is the clean contrast with SSRIs and the source of most evaluation points.
Method: Identify negative automatic thoughts, challenge distortions (catastrophising, overgeneralising), set behavioural experiments, build coping skills.
Effectiveness: Comparable to medication for moderate depression, with markedly LOWER relapse because the skills outlast the therapy (Hollon et al.; Butler et al., 2006 meta-analysis).
Limitations: Demands motivation, verbal fluency and effort; less accessible to severely depressed or non-verbal patients; therapist quality varies; slower initial relief than drugs.
Sociocultural treatment: group and community support
The sociocultural approach treats isolation and social context as maintainers of depression, so it uses the group as the healing agent. Group CBT and community support groups bring together people with similar difficulties under (or without) a therapist's guidance.
Mechanism: 'Universality' — realising others share the problem reduces shame and isolation; members model coping and give mutual support; the group normalises help-seeking.
Access and cost: One therapist reaches many patients, making it scalable and affordable — important where clinicians are scarce.
Evidence: Bright et al. (1999) found group therapy (both cognitive-behavioural and mutual-support formats) reduced depressive symptoms, showing the group format itself has therapeutic value.
Limitations: Sharing personal feelings in a group can clash with cultural norms of privacy or 'saving face'; less individualised; group dynamics can occasionally reinforce negative thinking.
Assessing effectiveness — and why it is so hard to measure
This is the section that separates top essays. It is not enough to say a treatment 'works'; you must show you understand why proving it works is difficult. Four problems recur.
Placebo. Much of an antidepressant's apparent benefit is matched by placebo. Kirsch et al. (2008) meta-analysed published AND unpublished antidepressant trials submitted to the US FDA and found the drug–placebo difference was small and clinically negligible for mild-to-moderate depression, becoming meaningful only in severe cases. So 'the patient improved on the drug' does not prove the DRUG worked.
Spontaneous remission. Depression is often episodic and self-limiting; some patients would recover anyway. Without a no-treatment control you cannot separate the treatment's effect from natural recovery.
Relapse. Short-term symptom relief is not long-term effectiveness. SSRIs show high relapse once stopped; CBT shows lower relapse because skills persist. Which treatment 'works better' depends on the time window you measure.
Individual differences. Severity, comorbidity, motivation, verbal ability, genetics and culture all move outcomes. An average trial effect can hide huge variation, so a treatment that is 'effective' on average can fail a specific patient.
Measurement itself. Depression is assessed with self-report scales (e.g. the Beck Depression Inventory) vulnerable to social desirability and demand characteristics — outcomes are estimates, not readings.
The role of culture in treatment
Most mainstream treatments — SSRIs, CBT — were developed and validated in Western, individualist contexts, so their effectiveness cannot be assumed to be universal. Culture shapes how distress is expressed (in many cultures depression presents as bodily symptoms such as fatigue or pain rather than reported sadness), what counts as an acceptable treatment, and whether talking openly about private feelings is appropriate at all.
Cultural mismatch. Kinzie et al. (1987) found Southeast Asian refugee patients responded poorly to therapy requiring open disclosure of personal feelings and had low adherence even to medication — a mismatch between a Western therapeutic model and the patients' cultural norms.
Culturally adapted CBT works better. Adapting CBT to local language, idioms of distress and values (rather than importing it unchanged) improves outcomes — evidence that the therapy is not universally 'plug-and-play'.
Somatic presentation. If a culture expresses depression as physical complaints, a clinician using a Western symptom checklist may misdiagnose or misjudge severity, distorting any effectiveness measure.
Etic vs. emic caution. Applying a Western treatment as if it were culture-free (an imposed etic) risks both poor effectiveness and ethical problems around informed, culturally-appropriate consent.
The interactionist approach: combining treatments
Because MDD has biological, cognitive and social contributors, an interactionist (eclectic) approach combines treatments across levels of analysis rather than betting on one. The logic is complementary: medication can reduce severe symptoms quickly enough that a patient becomes able to engage in therapy, while CBT builds the thinking and coping skills that lower relapse after the drug stops.
Evidence: March et al. (2007), the Treatment for Adolescents with Depression Study (TADS), compared fluoxetine alone, CBT alone, their COMBINATION, and placebo in depressed adolescents. The combination produced the best response rate, outperforming either treatment on its own.
Why it works: drugs act fast on symptoms; therapy acts durably on causes and relapse — combining them covers each treatment's weakness.
Evaluation: combined treatment is more expensive and demanding, and is not automatically best for every patient — mild cases may do fine on CBT alone, and adding a drug means adding side-effects. Interactionism is a strong DEFAULT, not a universal rule.
In a treatment ERQ, link every treatment to a proposed CAUSE (SSRIs to the serotonin hypothesis; CBT to negative schemas). This does double duty: it earns Criterion B (Knowledge) for showing WHY the treatment targets what it targets, and it sets up Criterion D (Critical thinking) via the treatment-etiology fallacy — the reminder that a treatment working does not prove the cause is its mirror image.
Common mistakes examiners penalise
Writing that SSRIs 'produce more serotonin'. They block REUPTAKE, increasing availability of existing serotonin — the wrong mechanism signals shaky knowledge.
Saying CBT changes brain chemistry. CBT targets COGNITIONS and behaviours (negative schemas), not neurotransmitters. Mixing up the mechanisms collapses the very contrast your evaluation depends on.
Treating 'the patient got better' as proof the treatment worked. Without controlling for placebo, spontaneous remission and individual differences, improvement proves nothing. Effectiveness is HARD to measure — say so.
Describing studies instead of USING them. Retelling aim/procedure/findings is Criterion C's floor, not its ceiling. You must state what the study PROVES or QUESTIONS about the treatment.
Answering the wrong number of treatments. 'Evaluate two treatments' requires TWO, both evaluated. One treatment richly evaluated still caps your marks because half the question is unaddressed.
All description, no evaluation. An essay that only explains how treatments work — with no effectiveness evidence, side-effects or methodological critique — cannot reach the upper critical-thinking bands, however accurate.
Assuming Western treatments are universal. Ignoring culture (mismatch, somatic presentation, need for adaptation) misses easy, high-value critical-thinking marks.
Worked examples
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Explain one biological treatment for major depressive disorder, with reference to one study. [9 marks]
- 1
One biological treatment for major depressive disorder (MDD) is drug therapy using Selective Serotonin Reuptake Inhibitors (SSRIs), such as fluoxetine. This treatment matches the serotonin hypothesis of depression — the proposed cause that reduced serotonin activity contributes to low mood. Mechanistically, when a neuron releases serotonin into the synapse, a reuptake transporter normally reabsorbs it into the presynaptic neuron. SSRIs block this transporter, so serotonin remains in the synapse longer and binds more to postsynaptic receptors, increasing serotonin availability and, over 2–6 weeks, relieving symptoms.
A newspaper reports: 'New study proves antidepressants work — 60% of patients recovered within three months.' Using what you know about measuring effectiveness, explain two reasons this headline overstates the evidence. [Worked reasoning]
- 1
Reason 1 — no control group / spontaneous remission. A 60% recovery rate is meaningless without a comparison. Depression is often episodic and self-limiting, so some of those patients would have recovered in three months WITHOUT any drug. Only comparing the drug group to a no-treatment or placebo group isolates the drug's specific effect. Kirsch et al. (2008) matters here: when antidepressants were compared with placebo across all trials (including unpublished ones), the difference was small except in severe depression — so a raw recovery figure with no placebo comparison tells us almost nothing about the drug itself.
Evaluate two treatments for one disorder. [22 marks]
- 1
Model essay
How it all connects
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Glossary
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Quick check
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Revision flashcards
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SSRIs (mechanism)
Selective Serotonin Reuptake Inhibitors block the reuptake transporter on the presynaptic neuron, so released serotonin stays in the synapse longer and binds more to postsynaptic receptors. They increase serotonin AVAILABILITY — they do not create more serotonin. Example: fluoxetine (Prozac).
Key takeaways
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- ✓
Mechanism: After a neuron releases serotonin into the synapse, a reuptake transporter normally pumps it back into the presynaptic neuron. SSRIs block that transporter, so serotonin lingers in the synapse and binds more to postsynaptic receptors. They raise serotonin AVAILABILITY — a common exam error is writing that they 'produce more serotonin'.
- ✓
Onset: Symptom relief typically takes 2–6 weeks, even though the chemical effect is immediate — a puzzle for the simple serotonin story.
- ✓
Effectiveness: Reliable for moderate-to-severe MDD; benefit over placebo is small for mild depression (Kirsch et al., 2008).
- ✓
Side-effects: Nausea, insomnia, agitation, sexual dysfunction; a boxed warning about increased suicidal ideation in adolescents.
- ✓
Relapse: High once medication stops, because the drug treats symptoms, not the thinking patterns or life circumstances behind them.
Practice — then mark it
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Get a Paper 2 essay marked: 'Evaluate two treatments for one disorder. [22]'
Get a Paper 2 essay marked: 'Evaluate two treatments for one disorder. [22]'
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