Esson 6 Interextionist Approach In Explaining The Onset And Treatment For SZ Flashcards
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 (such as losing a loved one, moving country etc) and daily hassles (such as concern about weight, worried about appearance) and including poor quality interactions in the family.
Treatment of SZ according to the interactionist model
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. 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.
Advantages of the Interactionist Approach
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.
Disadvantages of the Interactionist Approach
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. This means that both the cause of SZ and how it is treated should be taken with caution and assumptions should not be made.
The Diathesis Stress Model - explaining the onset of SZ
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.
Meehl’s model – in the original diathesis –stress model (Meehl – 1962) diathesis was entirely genetic and there was one specific gene ‘schizogene’. This led to the idea of a biologically based schizotypic personality, one characteristic of which is sensitivity to stress. According to Meehl, if a person does not have the schizogene then no amount of stress would lead to SZ. However, in carriers of the gene, chronic stress through childhood and adolescence especially the presence of the schizophrenogenic mother
could result in the development of the disorder.
However 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. 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
The modern understanding of stress as opposed to the original understanding of it (which was that stress was psychological in nature and due to parenting), is that it is anything that risks triggering schizophrenia e.g. cannabis use which makes it 7 times more likely for a person to develop schizophrenic symptoms. This is because cannabis
interferes with the dopamine system – although most people do not develop SZ through cannabis use as most people do not take cannabis but will develop SZ – this suggests that there are clearly other stressors which contribute to the development of SZ.
