IB Psychology HLTopic 1 — Mental Health DisordersPaper 1 & 2Cognitive approach~10 min read
Beck’s Cognitive Model of Depression
The biological pages treated depression as something happening to a person. Beck flipped it: what if the problem is the running commentary in someone’s head, and the way that commentary keeps finding evidence for itself? This is the model behind CBT, so it is worth getting exactly right.
📘 What you need to know
The cognitive approach explains behaviour through mental processes: thinking, memory, attention and interpretation.
Beck (1963) argued that MDD comes from faulty, irrational thought processes rather than from events themselves.
The negative cognitive triad is three linked negative views: of the self, of the world, and of the future.
Beck also proposed a diathesis–stress component: some people are predisposed, and stressful events set the disorder off.
The model’s biggest strength is that it works — CBT is built directly on it.
Its biggest weakness is that it explains how depressed thinking operates, but not why it started.
The negative cognitive triad
Beck built this from years of clinical work with depressed patients. He kept hearing the same three themes, and noticed they were not independent — each one fed the other two.
Draw this in the exam if a diagram is allowed. The two-way arrows are the part that earns credit, because they show why depressed thinking is so hard to break out of.
Most students learn the three corners and stop. The examiner is waiting for the loop — explain how one negative belief keeps generating the other two and you are already above the average answer.
Errors in depressed thinking
Beck suggested these habits of thought often trace back to difficult early experiences. They are not occasional slips; they are the default setting.
Thinking error
What it sounds like in real life
Personalisation
Blaming yourself for things you had no part in. The bus does not stop, and it feels like a personal rejection.
Negative automatic thoughts
Instantly finding the bad angle. A promotion becomes “more work I will fail at” before you have finished reading the email.
Catastrophising
Jumping to the worst possible ending. One low mark becomes failing the IB and ruining your life.
Overgeneralisation
Turning one event into a rule about everything. One bad date becomes “I will never find anyone”.
Why these matter clinically. Each error is a testable claim about the world. That is exactly what makes CBT possible: a therapist can ask for the evidence, and the evidence usually will not hold.
The diathesis–stress part
Beck did not claim thinking style causes depression on its own. He added that some people are predisposed — through genes, temperament or early experience — and that environmental stress then triggers the disorder. That is why two people can lose the same job and only one becomes depressed.
Diathesis–stress in one line
vulnerability (diathesis) + a stressful life event (stress) → the disorder appears
Use this model to tie the whole topic together: the genetic and neurochemical pages supply the vulnerability, and the sociocultural pages supply the stress.
Evaluation of Beck’s model
Strengths
It produced a working therapy. CBT comes straight out of this model and is now the most widely used psychological treatment for depression. A theory that generates effective treatment is doing real work.
Research evidence backs the link. Studies have repeatedly found that cognitive biases go together with depressive symptoms, in the direction Beck predicted.
It gives the patient something to do. Unlike an inherited-vulnerability account, this model points at something changeable, which is hopeful as well as useful.
The diathesis–stress element stops it being one-sided. Beck built biology and environment into his own theory.
Limitations
It explains how, not why. The model describes irrational thinking beautifully but says less about where those thought patterns came from.
The causal direction is unclear. Do negative thoughts cause low mood, or does low mood produce negative thoughts? Correlational evidence cannot settle it.
Cultural bias. The model centres on the individual and on one-to-one therapy. In collectivist cultures distress may be understood and treated through the group, so an individual-thoughts explanation may not fit.
It can slide into blaming the patient. If the problem is your thinking, it is easy to imply that a person with real poverty or real abuse is simply thinking about it wrongly.
EXAM QUESTION
Evaluate one cognitive explanation of one disorder. [22]
Beck is the obvious choice, but a lot of answers become a list of thinking errors with no argument.
Step 1: define MDD and name the approachCognitive approach = behaviour explained through mental processes.Step 2: explain the triad as a loopSelf ↔ world ↔ future, each belief supplying evidence for the others.Step 3: add the thinking errors and diathesis–stressTwo or three errors with a concrete example each. Then vulnerability plus trigger.Step 4: evaluate on four frontsPractical application (CBT), research support, direction of causality, cultural bias.Strongest closing move: compare with the biological explanationSay which one accounts for more of the evidence, and why. That is a judgement, and judgements score.
Link to concepts
Causality
Beck’s claim is that thinking comes first and mood follows. But if you are already depressed, negative thoughts arrive more easily — so the arrow may run the other way, or in both directions at once. This is a genuinely open question, and a good essay says so instead of picking a side.
Change
The model does not handle the shifting nature of depression very well. People are not equally depressed all the time; episodes come and go. A theory built on stable thought patterns has to explain why the symptoms are not stable.
💡 Exam tip
Give a one-line real example for every thinking error. Definitions alone read like a glossary.
Say “negative cognitive triad”, not just “the triad”. The full term is worth using once.
Diathesis–stress is your bridge between topics. Use it to connect Beck to McGuffin and Caspi.
Practical application is the strongest evaluation point here, because CBT exists and works.
Cultural bias is the strongest criticism. Explain why individual-focused therapy might not transfer, rather than just asserting it.
Beck built his model from depressed patients he had already treated, so the sample was not typical. That is a neat methodological point.
⚠ Common mix-up
Getting the three corners wrong. It is self, world, future — not past, present, future.
Treating the triad as a one-way sequence. The arrows go both ways; that is the mechanism.
Confusing catastrophising with overgeneralisation. Catastrophising is about the worst outcome; overgeneralisation is about applying one event to everything.
Saying Beck ignored biology. He included diathesis–stress. This is one of the most common wrong criticisms.
Describing CBT in detail here. That belongs in the treatment pages. Here you just say the model produced it.
Calling the model an experiment. It is a theory built from clinical observation.
Up next: Negative Schemas and Depression — underneath the triad sit even deeper beliefs, formed in childhood and stubbornly resistant to change. We look at early maladaptive schemas and the evidence that they last for years.
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