INTERACTIONIST APPROACH

• • The interactionist approach suggests that both biological and psychological explanations and therapies should be used in relation to SZ, to reflect both the biological and psychological aspects. Central to the idea of an interactionist approach is the use of the diathesis-stress model.
• • The original diathesis-stress model, as proposed by Meehl would now be considered outdated. He proposed that the diathesis is biological in origin which causes a schizotypic personality which in turn eventually manifests itself as schizophrenia. However, this only occurs when the diathesis is accompanied by a purely psychological stressor (excessive

  exposure to stress, particularly through the schizophrenogenic mother).
• • The renewed, modern understanding of stress is that it need not be biological in origin but could also be psychological, such as in the form of childhood trauma. The idea of a single schizogene has also been refuted by Ripke’s finding of over 108 candidate genes, whilst early childhood trauma causes dysfunction in the functioning of the HPA system (hypothalamic-pituitary-adrenal system), leading to a greater sensitivity to stressors in the future, and thus increasing the likelihood of developing SZ according to the diathesis-stress model.
• • Our understanding of diathesis has changed too, and is not limited to psychological factors but could also be biological in nature, as long as it increases the risk of developing SZ. For example, cannabis use may be considered a lifestyle stress which, when companied with childhood trauma, a biological predisposition or chronic stress, increases the risk of developing SZ by 7-fold.
• • If both psychological and biological explanations apply to SZ, the same approach should be used in SZ treatment. This is particularly the case as biological treatments appear to address the distal causes of SZ, whilst psychological treatments appear to be more well-suited in treating the proximal causes
  • Interactionist treatment usually starts with the patient taking antipsychotics to control symptoms, followed by CBT this enables the schizophrenic to be able to participate in CBT more successfully as the drug therapy should have reduced some of their symptoms prior to CBT
• A03

  — The original diathesis-stress model can be considered as an over-simplified explanation of SZ and outdated understanding of SZ. For example, Ripke et al demonstrated that there are over 108 candidate genes, each slightly increasing the risk of SZ, and so there is no single ‘schizogene’. Stress can come in many forms apart from the schizophrenogenic mother, such as high levels of expressed emotion, childhood trauma and excessive use of cannabis. Therefore, the diathesis is not exclusively biological, nor is the stressor exclusively psychological. may credit modern day accuracy of sz
• + evidence supporting role of vulnerability + triggers. Tienari et al investigated the impact of genetic vulnerability + psychological trigger. studied 19,000 Finnish children whose biological mothers were diagnosed with sz. In adulthood - high genetic risk group compared to control group of adoptees without genetic vulnerability. Adoptive parents were assessed for child-rearing style + low levels of empathy were associated with the development of sz, but only in the high genetic risk group. This shows that a combination of genetic vulnerability + family stress can lead to higher risk of sz
• A03

  + SUPPORTIVE STUDY -Tarrier et al randomly allocated 315 participants to three different conditions. first condition was having medication and CBT, the second condition was having medication and counselling and the third condition was a control group which only had medication. Participants in the two combination groups showed lower symptoms following trial than the medication-only group, though there was no difference in re-hospitalisation. This means that there is a clear practical advantage to adopting an interactionist approach to schizophrenia in terms of superior treatment outcomes.