The Interactionist Approach

Question 1

The diathesis-stress model: Vulnerability + trigger = SZ

Answer 1

Diathesis means vulnerability. Stress in this context refers to negative experiences that trigger the vulnerability

The diathesis-stress model says both a vulnerability and a trigger are needed to develop SZ. Individually may not create SZ - it is the interaction that is key

Question 2

The diathesis-stress model: Meehl’s model, diathesis is genetic

Answer 2

In the original diathesis-stress model, diathesis was entirely the result of a single ‘schizogene’

Meehl (1962) argued that someone without this gene should never develop SZ, no matter how much stress they were exposed to

But a person who does have the gene is vulnerable to the effects of chronic stress (especially schizophrenogenic mother)

The schizogene is necessary but not sufficient for the development of SZ

Question 3

The diathesis-stress model: Modern understanding of diathesis

Answer 3

It is now believed that diathesis is not due to a single ‘schizogene’. Instead it is thought that many genes increase vulnerability

Also, diathesis doesn’t have to be genetic. It could be early psychological trauma affecting brain development

For example, child abuse affects the hypothalamic-pituitary-adrenal (HPA) system, making a child vulnerable to stress

Question 4

The diathesis-stress model: Modern understanding of stress

Answer 4

A modern definition of stress includes anything that risks triggering SZ. Can be psychological (e.g. parenting) or biological (e.g. cannabis use)

Cannabis use can increase the risk of SZ up to 7x depending on the dose because it interferes with the dopamine system

Question 5

Treatment according to the interactionist model: Antipsychotic medication and CBT

Answer 5

Antipsychotic drugs taken in combination with CBT

But this requires adopting an interactionist model - it is not possible to adopt a purely biological approach, tell patients that their condition is purely biological and then treat them with CBT (Turkington et al. 2006)

Question 6

Treatment according to the interactionist model: UK adopts more interactionist approach compared to US

Answer 6

In Britain it is increasingly standard practice to treat patients with a combination of drugs and CBT

In the US there is more of a conflict between psychological and biological models of SZ and this may have led to slower adoption of the interactionist approach