Explanation

• What does the biological approach emphasize in psychology?


  The importance of physical processes in the body
• What are the main components involved in the biological approach?


  • Genetic influences
  • Neural function
  • Brain structure
• What are the biological explanations for OCD?


  • Genetic explanations
  • Neural explanations
• What do genes consist of and what do they code for?


  Genes consist of DNA and code for physical and psychological features
• How are genes related to OCD?


  Genes are involved in individual vulnerability for OCD
• What percentage of Lewis's patients with OCD had a parent with the disorder?


  37%
• What does the diathesis-stress model suggest about OCD?


  Genes increase the likelihood of developing OCD, but an environmental stressor is needed to trigger it
• What are candidate genes in relation to OCD?


  • Genes that create vulnerability for OCD
  • Involved in regulating serotonin development
• What is the role of the SERT gene in OCD?


  The SERT gene affects serotonin transport, leading to lower serotonin levels
• What does it mean that OCD is polygenic?

  OCD is caused by several genes rather than a single gene
• How many different genes did Taylor's meta-analysis find to be involved in OCD?


  Up to 230 different genes
• What does aetiologically heterogenous mean in the context of OCD?


  • The origin of OCD has different causes
  • Different genetic variations may cause different types of OCD
• What types of genetic studies are used to investigate genetics in OCD?

  • Twin studies
  • Adoption studies
  • Family history studies
• How do twin studies assess genetic influence on OCD?


  • Compare identical (MZ) and non-identical (DZ) twins
  • Higher similarity in MZ twins indicates stronger genetic influence
• What is the concordance rate in twin studies?


  The percentage of twins that share the same characteristic
• What do we expect regarding concordance rates for MZ and DZ twins in relation to OCD?


  MZ twins should show higher concordance rates than DZ twins