The interactionist approach to schizophrenia

• The interactionist approach of schizophrenia - Acknowledges there are biological, psychological and societal factors in the development of Schizophrenia

  Biological factors:

  • Genetic vulnerability
  • Neurochemical + Neurological abnormality

  Psychological factors:

  • Stress
• Explaining the interactionist approach: The diathesis-stress model

  • Both vulnerability and stress-trigger are important to develop the condition

  Diathesis - Vulnerability

  Stress - negative psychological experience
• The diathesis-stress model - Meehl's model

  • Diathesis is genetic - Schizogene
  • Development of a biologically based schizotypic personality - Sensitivity to stress
  • Carriers of the gene - Chronic stress through childhood and adolescence and schizophrenocgenic mother
• The diathesis-stress model - Modern understanding of diathesis

  • Many genes increase genetic vulnerability - No schizogene
  • Many factors beyond genetic - Psychological trauma
  • Read et al: Neurodevelopmental model - Early trauma alters developing brain
• The diathesis-stress model - The modern understanding of stress

  • Anything that risks triggering schizophrenia

  E.g. Weed usage:

  • Stressor - Increases risk of S by up to 7 times
  • Interferes with dopamine system
  • Must be more - Not all weed smokers develop S after smoking
• Treatment according to the interactionist model

  Compatible with biological and psychological treatments - Acknowledges both

  • Combines antipsychotic meds and psychological therapies e.g. CBT
  • Turkington et et al: Possible to believe biological causes of S and practise CBT to relive psychological symptoms
  • Britain - Practise to treat people with a combinations of antipsychotic drugs and CBT
  • USA - Conflict with psychological and biological models
  • Unusual to treat S with psychological therapies alone
• Evaluation of the interactionist approach - Original diathesis-stress model is over-simple

  • Schizogene and schizophrenic parenting styles - Over-simple
  • Multiple genes increase S - Small effects on its own
  • Stress can be in many forms - Including dysfunctional parenting
  • Vulnerability and stress don't have one single source

  Limitation: Problem for old model which still forms the basis of new ones
• Evaluation of the interactionist approach - Support for the effectiveness of combinations of treatments

  • Tarrier et al: Over 300 ppl with S were randomly allocation to medication of CBT, Medication and supportive counselling or a control group (Med only)
  • Findings - Two combination groups lower symptom levels than med only

  Strength: Practical advantage to adopting an interactionist approach with more treatment outcomes - Highlight importance of interactionist approach