Unipolar depression: Beck's cognitive triad (non-biological)

The cognitive triad

Aaron Beck (1967) proposed that depression is maintained by automatic negative thoughts about three things:

• the self: 'I am worthless'
• the world: 'everyone rejects me'
• the future: 'things will never get better'.

Schemas and cognitive errors

Beck argued people develop negative self-schemas, often from childhood experiences such as criticism or bullying. These schemas bias how new information is processed through cognitive errors:

• arbitrary inference: drawing a conclusion without evidence
• selective abstraction: focusing on one negative detail
• overgeneralisation: one failure means 'I always fail'
• magnification and minimisation: exaggerating bad events, playing down good ones
• personalisation: blaming yourself for things outside your control.

Evaluation

• Application: it is the basis of CBT, which is effective (Hans and Hiller, 2013; DeRubeis et al., 2005), supporting the role of thinking.
• Supporting research: Ma, Quan and Liu (2014) found that core self-evaluation correlated negatively with depression (r = -.636): the more negatively students evaluated themselves, the more depressed they were.
• Cause or effect? Much evidence is correlational; negative thinking could be a symptom of depression rather than its cause.
• Blame: it locates the problem in the person's thinking and may underplay real life circumstances such as poverty or abuse.
• Holistic or reductionist? More holistic than biology, but ignores biological factors; a diathesis-stress view combines both.

Worked example

Jon failed one maths test and now says 'I'm stupid, I'll never pass anything.' Analyse this using Beck's theory.

1. 'I'm stupid' is a negative view of the self; 'I'll never pass anything' is a negative view of the future: two parts of the triad.
2. Going from one test to 'anything' is overgeneralisation.
3. Beck would say a negative self-schema biases Jon's interpretation, maintaining low mood.
4. AO3: CBT challenging these thoughts is effective, supporting the theory, but the thoughts could also be a result of low mood.

Answer: Identify triad elements and cognitive errors, then evaluate.

Check yourself

1. Which three areas form Beck's cognitive triad?
   • Mind, body and spirit
   • Self, world and future
   • Past, present and future
   • Family, friends and work
   Show answer

   Self, world and future. Self, world (experiences) and future.

2. 'I made one mistake at work, so I am useless at everything.' Which cognitive error is this?
   • Personalisation
   • Minimisation
   • Arbitrary inference
   • Overgeneralisation
   Show answer

   Overgeneralisation. One event becomes a general rule.

3. Blaming yourself because it rained on a friend's wedding day is an example of
   • selective abstraction
   • personalisation
   • magnification
   • overgeneralisation
   Show answer

   personalisation. Taking responsibility for events outside your control.

4. In which year did Beck propose the cognitive triad?
   Show answer

   1967. Beck (1967).

5. Explain why evidence for Beck's theory may not show that negative thinking causes depression.
   Show answer

   The evidence is mostly correlational, so negative thoughts might be a symptom or result of depression rather than its cause.. Correlation does not show which comes first.

6. Explain what Beck meant by a negative self-schema.
   Show answer

   A negative self-schema is a set of negative beliefs about oneself, often formed in childhood through experiences such as criticism, which bias how new information is interpreted.. Schemas are negative belief frameworks that bias processing.

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Sources

• Pearson Edexcel International Advanced Subsidiary/Advanced Level in Psychology specification (issue January 2026)
• Pearson IAL Psychology component guide: WPS04 (Issue 2, November 2024)
• Beck (2008), The evolution of the cognitive model of depression and its neurobiological correlates, American Journal of Psychiatry
• Pearson IAL Psychology summary of studies: WPS04
• DeRubeis et al. (2005), Cognitive therapy vs medications in the treatment of moderate to severe depression, Archives of General Psychiatry 62
• Pearson WPS04/01 examiners' report, June 2025

Last updated 8 November 2026. Spotted a mistake? Tell us.