Lesson 6 – Interactionist Approach in explaining and treating Schizophrenia Flashcards
What is the interactionist approach
The interactionist approach (also referred as the biosocial approach) is an approach that acknowledges that there are biological, psychological and societal factors in the development of SZ. Biological factors include genetic vulnerability and neurochemical (e.g. dopamine) and neurological (brain) abnormality. Psychological factors include stress resulting from life events and daily hassles, including poor quality interactions in the family.
Diathesis stress model
Diathesis means vulnerability – we have seen that SZ has a genetic component in terms of vulnerability. In this context, stress simply means a negative psychological experience. This model states that both a vulnerability to SZ and a stress-trigger are necessary in order to develop the condition. One or more underlying factors make a person particularly vulnerable to developing SZ but the onset of the condition is triggered by stress.
Original diathesis stress model
Meehl’s model – in the original diathesis –stress model (Meehl – 1962) diathesis was entirely genetic and there was one specific gene ‘schizogene’
Modern understanding of diathesis
The modern understanding of diathesis is that now it is clear that many genes increase genetic vulnerability and there is no single gene. Modern views of diathesis include genes but also psychological trauma (Ingram and Luxton, 2005) so trauma becomes the diathesis rather than the stressor.
Neurodevelopmental model
Read et al. (2001) proposed a neurodevelopmental model in which early trauma affects brain development. In fact, early and severe enough trauma such as child abuse can seriously affect brain development e.g. HPA (hypothalamic pituitary adrenal) systems can become overactive making the person more vulnerable to stress
Treatment of schizophrenia with interactionist approach
The interactionist model of SZ acknowledges both biological and psychological factors in SZ and is therefore compatible with both biological and psychological treatments – in particular the model is associated with combining antipsychotic medication and psychological therapies such as CBT.
Explanation of treatments for schizophrenia using interactionist approach
In Britain it is increasingly standard practice to treat patients with a combination of drugs and CBT. It is unusual to treat SZ using psychological therapies alone this is because SZ is a complex psychotic disorder, drug therapy will be first given to control the symptoms of SZ, the drug therapy will be used in a hospital setting perhaps with token economy to manage the behaviour of patients with SZ. Then CBT and family therapy will precede this.
Strengths of the interactionist approach for treating schizophrenia
Evidence for the role of vulnerability and triggers – there is research support for the dual role for genetic vulnerability to SZ and stress triggers. For example, Tienari et al. (2004) studied children adopted away from schizophrenic mothers. The adoptive parents’ parenting styles were assessed and compared with a control group of adoptees with no genetic risk. A child-rearing style with high levels of criticism and conflict and low levels of empathy was implicated in the development of schizophrenia but only for children with a high genetic risk. This is very strong direct support for the interactionist approach – genetic vulnerability and family-related stress combine in the development of SZ.
Support for the effectiveness of combination of treatments - Another strength is the usefulness of the interactionist approach in treatment of SZ – Tarrier et al. (2004) randomly allocated 315 patients to (1) medication and CBT group or (2) a medication and supportive counselling group, or (3) a control group. Patients in the two combination groups (groups 1 and 2) showed lower symptom levels than those in the control group (medication only) – but no difference in hospital readmission. Studies like this show that there is a clear practical advantage to adopting an interactionist approach in the form of superior treatment outcomes.
Weaknesses of the interactionist approach for treating schizophrenia
One limitation is that the original diathesis-stress model is too simplistic – multiple genes increase vulnerability, each with a small effect on its own –there is no schizogene. Stress comes in many forms, including dysfunctional parenting. Researchers now believe stress can also include biological factors. For example, Houston et al. (2008) found childhood sexual trauma was a diathesis and cannabis use a trigger. This shows that the old idea of diathesis as biological and stress as psychological has turned out to be overly simple
Another limitation is we don’t know exactly how diathesis stress work –There is strong evidence to suggest that some sort of underlying vulnerability coupled with stress can lead to schizophrenia. But we don’t understand the mechanisms by which symptoms of schizophrenia appear and how both vulnerability and stress produce them. This does not undermine support for the approach, but it does mean we have an incomplete understanding of the actual medication.
A further limitation is the treatment-causation fallacy - Turkington et al. (2006) argue the fact that combined biological and psychological therapies are more effective than either on their own does not necessarily mean the interactionist approach to schizophrenia is correct. Similarly the fact that drugs help does not mean that schizophrenia is biological in origin. This error of logic is called the treatment-causation fallacy. It means that the superior outcomes of combined therapies should not be over-interpreted in terms of evidence in support of the interactionist approach.
