Interactionist Approach - SZ

Question 1

Diathesis-Stress Model

Answer 1

1) Diathesis means vulnerability - Stress refers to negative experiences that trigger the vulnerability.

2) The diathesis-stress model says both a vulnerability and a trigger are needed to develop SZ.

Question 2

Meehl’s Model

Answer 2

1) In the original diathesis-stress model, diathesis was entirely the result of a single ‘schizogene’.
2) Meehl (1962) argued that someone without this gene never develop SZ.
3) But a person who does have the gene is vulnerable to the effects of chronic stress (especially a schizophrenogenic mother).
–> The schizogene is necessary but not sufficient for the development of schizophrenia.

Question 3

Modern Understanding - Diathesis

Answer 3

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

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

E.g. child abuse affects the hypothalamic-pituitary-adrenal (HPA) system, making a child vulnerable to stress.

Question 4

Modern Understanding - Stress

Answer 4

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

RESEARCH SUPPORT:
E.g. Houston et al. (2008), childhood sexual trauma emerged as a vulnerability factor while cannabis use was a trigger.
–> This shows that the old idea of diathesis as biological and stress as psychological is overly simple.

Question 5

Interactionist Treatment

Answer 5

1) Acknowledges both biological and psychological factors in SZ - Antipsychotic drugs taken in combination with CBT.

Question 6

Research Support - Treatments

Answer 6

Tarrier et al. (2004)

1) Studied 315 patients who were randomly allocated to a medication plus CBT group, medication plus supportive counselling or a control group.

2) Patients in the 2 combination groups showed lower symptom levels than those in the control group (medication only).

Question 7

Strength of Approach

Answer 7

SUPPORT OF DUAL ROLE

1) Tienari et al. (2004) studied children adopted away from mothers diagnosed with SZ. The adoptive parents’ parenting styles were assessed and compared with a control group of adoptees with no
genetic risk.

2) A child-rearing style with high levels of criticism and conflict and low levels of empathy was implicated in the development of SZ but only for children with a high genetic risk.

–> Shows that a combination of genetic vulnerability and family stress leads to increased risk of SZ.

Question 8

Limitation of Model

Answer 8

OVERSIMPLIFIED

1) Multiple genes increase vulnerability, each with a small effect on its own - there is no schizogene. Stress comes in many forms,
including dysfunctional parenting.

2) Researchers now believe stress can also include biological factors. For example, Houston et al. (2008).

–> This means that there are multiple factors, biological and psychological, affecting both diathesis and stress.