Interactionist approach

• Interactionist approach

  Acknowledges that there are biological and psychological factors which contribute to the development of SZ
• Diathesis-stress model

  Both a vulnerability to schizophrenia and a stress-trigger are necessary to develop SZ.

  Underlying factors make a person vulnerable but the trigger is stress
• Meehl's diathesis stress model

  Diathesis (vulnerability) was genetic and a result of the 'schizogene'.

  Chronic stress through childhood and adolescence, particularly schizophrenogenic mother, could result in development of SZ.
• Modern understanding of model

  Diathesis

  • many genes increase genetic vulnerability.
  • includes psychological trauma, such as child abuse, which can alter brain development.

  Stress

  • anything that risks triggering SZ.
  • e.g. cannabis use
• Treatment according to interactionist model

  Combining antipsychotic medication + psychological therapies (particularly CBT)
• Research support

  Tienari et al

  19,000 Finnish children whose biological mothers had been diagnosed with SZ

  This genetic risk group compared to control group of adoptees w/o family history of SZ.

  Adoptive parents assessed and children who had parents with negative environment were associated with development of SZ but only in high genetic risk group
• Real world application

  Combination of drug treatment and psychological therapies enhances the effectiveness.
• Limitation - original model

  Original model is too simplistic.

  Doesn't acknowledge that biological + psychological factors can be diathesis and stress.

  Supports modern model