GENETIC EXPLANATIONS

• HOW IS OCD EXPLAINED?

  biological approach
• NAME OF IDENTICAL TWINS?

  monozygotic
• WHAT DO GENETIC EXPLANATIONS OF OCD SUGGEST?

  OCD is inherited as a result of specific genes
• WHAT TYPE OF CONDITION IS OCD?

  polygenic
• POLYGENIC?

  trait/ characteristic influenced by multiple genes
• WHAT GENE REGULATES THE FUNCTION OF SEROTONIN?

  SERT
• WHAT GENES ARE MUTATED IN INDIVIDUALS WITH OCD?

  SERT and COMT
• WHAT DOES THE MUTATION OF THE SERT GENE CAUSE?

  increase in reabsorption of serotonin into presynaptic neurone (decreases level of serotonin in synapse and therefore its effect on the postsynaptic neurone)
• WHAT CONTAINS THE NEUROTRANSMITTERS IN THE SYNAPSE?

  vesicles
• WHAT GENE REGULATES THE FUNCTION OF DOPAMINE?


  COMT
• WHAT DOES THE COMT GENE MUTATION CAUSE?

  decrease in reabsorption of dopamine (higher level of dopamine in synapse)
• WHAT IS DOPAMINE LINKED TO?

  motivation, rewards and compulsions
• STRENGTH OF THE GENETIC EXPLANATIONS?

  research support
• WHAT RESEARCH SUPPORT DOES IT HAVE?

  Nestadt's meta-analysis of twin studies
• WHAT DID NESTADT DISCOVER?

  concordance rate for OCD in MZ twins was 68% but only 31% for DZ twins
• WHAT DOES THE DIATHESIS-STRESS MODEL STATE?

  certain genes make individuals more likely to suffer from a mental disorder but some environmental stress is necessary to trigger the condition
• WEAKNESS OF GENETIC EXPLANATIONS?

  • methodological problems with twin/ family studies (shared environments, learning through social learning theory)
  • does not consider environmental factors (trauma)
• WHAT APPROACH MAY BE MORE APPROPRIATE THAN THE GENETIC EXPLANATION?

  psychodynamic approach (explores previous traumas)