interactionist approach to schizoprenia

• meehls model:

  Diathesis = entirely genetic - schizogene

  Schizogene - schizotypic personality. Very sensitive to stress.

  No schizogene - High stress won’t cause SZ

  Gene carriers - Psychological stress in childhood, e.g. schizophrenogenic mother = SZ development
• modern:

  Many genes increase vulnerability (Ripke 2014)

  Psychological trauma can also be a diathesis (Ingram & Luxton 2005)

  Read (2001) - Early trauma affects brain development, such as HPA stress system

  Modern understanding of stress also differs - used to be just psychological but now seen as being possibly biological too (Cannabis)
• Tienari 2004

  impact of genetic vulnerability and a psychological trigger (dysfunctional parenting) 19,000 Finnish children whose biological mothers had been diagnosed with schizophrenia. adulthood this high genetic risk group were compared to a control group of adoptees without a family history of schizophrenia

  Results: Adoptive parents had been assessed for child-rearing style and it was found that high levels of criticism, hostility and low levels of empathy were strongly associated with the development of schizophrenia, but only in the high genetic risk group.
• One strength of the interactionist approach to schizophrenia is evidence supporting the role of both vulnerability and triggers. Tienari 2004 research. This shows that a combination of genetic vulnerability and family stress can lead to greatly increased risk of schizophrenia.
• But pps may have trauma result of adoption process - especially true the older the children are when they are adopted. Under the modern interpretation of dsm, early trauma can act as a diathesis difficult to separate out the influence of genetics or early life trauma causing diathesis. With this in mind Tienari’s results still support the modern understanding of the S-D model because this model allows for either a genetic or early trauma diathesis HOWEVER it would be difficult to support the original model as this only allows a genetic diathesis.
• Another limitation of the interactionist approach is that there has not been much empirical research into the impact of social factors on the development of schizophrenia. This means we cannot say how important these factors really are. For example, although Tienari 2004 showed an association between dysfunctional parenting and the development of schizophrenia, it does not prove causation. It could be argued that people who develop schizophrenia are more likely to experience poor parenting rather than vice versa.
• -original dsm is oversimplified. It is now clear that the meehls model diathesis schizogene stress schizophrenogenic parenting simplistic. Multiple genes in multiple combinations influence diathesis Stress also comes in many forms e.g dysfunctional parenting. diathesis can influenced by psychological factors and stress biological as well as psychological. Houston 2008 found childhood sexual abuse emerge major influence vulnerability to sz and cannabis use major trigger. means multiple factors, both bio and psych, affecting both diathesis and stress, supporting the modern dsm.
• +nature-nurture debate is the potential rwa .Tarrier 2004 found in their randomised treatment trial that the combination of medication & psychological therapies both led lower symptoms & better outcomes for the patients. This illustrates the usefulness of an interactionist approach in treating schizophrenia because bringing about both bio and environmental changes together increased the efficacy of the treatment.This implies that adopting nature and nurture perspective together has practical value in treatment too and that both contribute significantly to improving outcomes.