Twin records show depression is more similar in genetically closer pairs. A family study of addiction also shows elevated risk among biological relatives, although many relatives never develop the problem.
Compare genetic explanations of depression and addiction using the material.
52 exam-style questions on Edexcel GCSE Psychology 3.1 Psychological problems, covering 3.1.1 Symptoms and features (ICD), 3.1.2 Incidence over time, 3.1.3 Effects on individuals and society, 3.1.4 Influence of genes as an explanation, 3.1.5 Cognitive theory explanation of depression, 3.1.6 Learning theory explanation of addiction, 3.1.7 CBT as a treatment, and 3.1.8 Drugs as a treatment. Each one has a worked solution and a mark scheme showing where the marks go.