Cognitive Behavioural Therapy
Definition
Cognitive Behavioural Therapy (CBT) is a family of structured psychological treatments built on the premise that thoughts, behaviour and emotion influence one another, and that changing one changes the others.
It is typically time-limited, agenda-driven, and involves work between sessions. The therapist and client build a shared formulation: an explicit account of what is maintaining the problem now, which matters more in CBT than what originally caused it.
History
CBT is usually traced to two lines of work that converged in the 1960s and 1970s.
Aaron Beck, working with depressed patients, noticed a stream of negative thoughts they had not been asked about, and built cognitive therapy around modifying them. Albert Ellis had independently developed Rational Emotive Behaviour Therapy along similar lines.
The behavioural half came earlier, from applying learning theory to clinical problems, particularly Wolpe's work on systematic desensitisation for phobias.
The two traditions merged unevenly, and the result is less a single treatment than a family with a shared vocabulary.
Theory
The central claim is that psychological distress is maintained by patterns that are, in principle, observable and modifiable:
- Cognitive: appraisals, assumptions, attentional biases and interpretations.
- Behavioural: avoidance, safety behaviours, withdrawal, and the short-term relief they produce.
- Physiological: arousal, and how it is interpreted.
Maintenance is the key idea. A panic model does not require a theory of why the first attack happened; it requires an account of why attacks keep happening, which is usually catastrophic misinterpretation of bodily sensations plus safety behaviours that prevent disconfirmation.
Research
CBT is the most extensively trialled psychological treatment, which is a fact about the research literature as much as about the treatment.
Effects are well established for anxiety disorders, depression, OCD and PTSD, strongest and most consistent in the anxiety disorders. Effect sizes in recent, better-controlled trials are typically smaller than in the early literature, which is the expected pattern as trial quality improves.
Three caveats worth holding:
- The comparison condition matters enormously. CBT versus waitlist and CBT versus an active alternative are different questions with different answers.
- Most trials exclude the comorbidity that is normal in routine practice.
- Publication bias has been demonstrated in this literature specifically.
Applications
Routinely used for anxiety disorders, depression, OCD, PTSD, insomnia (CBT-I), eating disorders, chronic pain and psychosis, and increasingly delivered in low-intensity, guided self-help and digital formats.
Disorder-specific protocols matter more than the general label. CBT for panic and CBT for social anxiety share a vocabulary and very little else in their actual procedures.
Criticism
- The cognitive part may not be the active ingredient. Component studies frequently find behavioural activation alone performs comparably to full CBT for depression.
- It is over-represented in the evidence base partly because it is manualised and therefore easy to trial, not necessarily because it works better than treatments that are harder to standardise.
- Protocol adherence in real services is low, so what is delivered often differs from what was tested.
- Cultural assumptions are embedded in what counts as a distorted thought, and the protocols were developed on narrow samples.
References
- Beck, A. T. (1979). Cognitive Therapy of Depression. Guilford Press.
- Clark, D. M. (1986). A cognitive approach to panic. Behaviour Research and Therapy, 24(4), 461-470.
- Cuijpers, P., et al. (2019). Was Eysenck right after all? A reassessment of the effects of psychotherapy for adult depression. Epidemiology and Psychiatric Sciences, 28(1), 21-30.
- Dimidjian, S., et al. (2006). Randomized trial of behavioral activation, cognitive therapy, and antidepressant medication. Journal of Consulting and Clinical Psychology, 74(4), 658-670.