Interactionist approach

Question 1

What is the interactionist approach?

Answer 1

• An explanation which acknowledges a broad range of factors, including biological and psychological ones.
• Also known as biosocial approach.

Question 2

What is the diathesis-stress model?

Answer 2

• SZ is explained as a result of underlying vulnerability (diathesis) and an environmental trigger (stressor)

Question 3

What was Meehl’s original model?

Answer 3

• Vulnerability entirely genetic, the result of a single schizogene. Without this gene, no amount of stress would lead to SZ.
• In carriers of the gene, chronic stress during childhood and adolesence (in particular schizophrenogenic mother) could result in development of the disorder.

Question 4

How is the current model different to Meehl’s?

Answer 4

• Schizophrenia is a polygenic disorder, not caused by a specific gene. Also, vulnerability isn’t always genetic, it could be due to psychological trauma.
• Stress isn’t always psychological, it can be anything that risks triggering SZ such as cannabis (up to 7x triggers it as it interferes with dopamine system.)

Question 5

How does this approach attempt to treat schizophrenia?

Answer 5

• Combines antipsychotic drugs and psychological therapies, most commonly CBT.
• Leads to reduced symptoms.

Question 6

Strength: research support for vulnerability and triggers

Answer 6

• Tienari et al (2004) investigated impact of genetic vulnerability and psychological trigger on 19000 Finnish children with a schizophrenic mother.
• In adulthood, this high genetic risk group were compared to a control group of adoptees without a family history of SZ.
• Found that high levels of criticism, hostility and low levels of empathy were associated with the development of SZ, only in the high genetic risk group.

Question 7

Strength: real world application

Answer 7

• Tarrier et al. (2004) randomly allocated 315 ppts to (1) medication + CBT, (2) medication + counselling, (3) control just medication
• Ppts in two combination group showed lower symptoms following the trial than the control group
• There is a clear practical advantage of the combination of treatment.

Question 8

Weakness: Diathesis stress model is complex

Answer 8

• Original diathesis-stress model is oversimplified
• The original model that portrayed diathesis as a single schizogene and portrayed stress as schizophrenogenic parenting is hopelessly simplistic. Multiple genes in multiple combinations influence diathesis. Stress also comes in many forms, including but not limited to dysfunctional parenting.
• Diathesis can also be influenced by psychological factors and stress can be biological as well as psychological.
• There are multiple factors, both biological and psychological, affecting both diathesis and stress, supporting the modern understanding of both diathesis and stress.