NOT DONE The interactionist approach to schizophrenia

Interactionist approach

A way to explain the development of behaviour in terms of a range of factors, including biological and psychological ones.

Factors don’t add together but combine in a way that can’t be predicted by each one separately

Diathesis-stress model (DS)

An interactionist approach to explaining behaviour.

Schizophrenia is explained as the result of an underlying vulnerability (diathesis) and a precipitating factor (stressor), both of which are necessary for the onset of schizophrenia.

In early versions of the model, diathesis was genetic and stressors were psychological.

Genes and trauma are seen as diatheses and stress can be biological or psychological in nature

Meehl’s model

In the original DS model diathesis was genetic, the result of a ‘schizogene’. Led to the idea of a biologically-based schizotypic personality - 1 characteristic of which is sensitivity to stress.

According to Meehl if a person doesn’t have the schizogene then no amount of stress would lead to schizophrenia.

In carriers of the gene, chronic stress through childhood and adolescence can result in the development in the condition. The schizogene is necessary but not sufficient for the development of schizophrenia.

Modern understanding of diathesis

1 way in which our understanding of diathesis has changed is that it is now clear that many genes appear to increase genetic vulnerability.

Modern views of diathesis include a range of factors beyond the genetic and psychological trauma - so trauma becomes the diathesis rather than the stressor.

Read proposed a neurodevelopmental model where early trauma affects the developing brain.

Early and severe enough trauma can seriously affect many aspects of brain development. The hypothalamic-pituitary-adrenal system can become overactive and makes someone more vulnerable to later stress.

Modern understanding of stress

In the original DS model stress was seen as psychological in nature, related to parenting.

Although psychological stress including that resulting from parenting may be considered a modern definition of stress. - Anything that risks initiating schizophrenia.

Much of the recent research into factors which might initiate an episode of schizophrenia has concerned cannab!s use. In terms of the DS model cannab!s is a stressor as it increases the risk of schizophrenia up to x7 according to dose. This may be because it affects the dopamine system.

Most people do not develop schizophrenia after using cannab!s as they lack the requisite vulnerability factors.

Treatment according to the interactionist model

Turkington

The interactionist model acknowledges both biological and psychological factors in schizophrenia and is compatible for these treatments. The model is associated with combining antipsychotics with psychological therapies like CBT.

Pointed out that it is possible to believe in biological causes and practise CBT. This requires adopting an interactionist model and it is not possible to adopt a purely biological approach.