A01- Interactionist

• Interactionist approach

  Acknowledges biological (genetic vulnerability and neurochemical/neurological abnormailty), psychological (stress coming life events inluding poor quality interactions with family) and societal forces involved in the development of schizophrenia.
• The Diathesis-stress model

  Diathesis creates the predisposition, stress provides a trigger. Model suggests both a vulnerability to schiz and a stress trigger are necessary to develop the condition.
• Meehl's model


  In the original diathesis-stress model, diathesis was entirely genetic, a result from a single schizogene. This led to the development of a biologically based schizotypic personality.
• Biologically based schizotypic personality


  If a person does not have the shcizogene then no amount of stress would cause schiz but in carriers of the gene, chronic stress in childhood through childhood, like the presence of a schizophrenogenic mother, could lead to development of schiz.
• Modern understanding of diathesis


  There is no single schizogene amd many genes each appear to increase genetic vulnerability only slightly. Psychological trauma emphasised which became the diathesis rather than the stressor.
• Read et al


  Proposed a neurodevelopmental model in which early trauma alters the developing brain. For example, the hypothalamic-pituitary-adrenal (HPA) system can become overactive, making one more vulnerable to later stress
• Modern understanding of stress


  Includes anything that risks triggering schiz. Cannabis use is a stressor as it increases risk of schiz by up to 7 times. Cannabis interferes with the dopamine system. But most people who smoke do not develop schiz so there may be one or more vulnerability factors. Whereas the original diathesis-stress model sees stress as psychological in nature and in particular, related to parenting.
• Treatment according to the interactionist model

  It acknowledges the biological and psychological factors in schiz so is compatible with both biological and psychological treatments. Model is associated with combining anti-psychotic medication and psychological therapies.
• Turkington et al


  Points out it is perfectly possible to believe in biological causes of schiz and still practise CBT to relieve psychological symptoms. But this requires adopting an interactionist approach.
• Schizophrenic treatments across Britain and USA

  In Britain, it is standard practice to treat people with combination of anti-psychotics and CBT. But in the USA, there is a history of conflict between psychological and biological theories and thus slower adoption of interactionist approach. But it is unusuall to treat patients with just psychological therapies.