The interactionist approach to SZ

Question 1

Interactionist approach

Answer 1

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

Question 2

Diathesis-stress model

Answer 2

both a vulnerability of schizophrenia and a stress-tigger are necessary in order for it to develop.

Question 3

Also called the ‘Biosocial approach’ which is

Answer 3

acknowledges different factors in the development of SZ

Question 4

biological factors

Answer 4

genetic vulnerability, neurochemical and neurological abnormality

Question 5

Psychological factors

Answer 5

stress eg from life events and daily hassles

Question 6

Social factors

Answer 6

poor quality interactions in family

Question 7

diathesis literal meaning

Answer 7

vulnerability

Question 8

stress literal meaning

Answer 8

negative experience

Question 9

Meehls’s model

diathesis-stress

Answer 9

• In the original model, diathesis was entirely genetic and as a result of a single ‘schizogene’
• Led to biologically based idea of schizotypic personality with one characteristic of being sensitive to stress
• So if the person does not have the schizogene then no amount of stress could cause the disorder
• However, in carriers of the gene, chronic stress in childhood would, in particular having a schizophrenogenic mother, could result in the development of the disorder

Question 10

Modern understanding of diathesis

Answer 10

• Many genes actually increase genetic vulnerability
• No schizogene (Ripke et al)
• Range of factors beyond just genetic, including psychological trauma (Ingram and Luxton) so trauma becomes the diathesis rather than the stressor

Question 11

Read et al

Modern understanding of diathesis

Answer 11

proposed a neurodevelopmental model in which early trauma alters the developing brain
* Child abuse can seriously affect brain development
* Eg the hypothalamic-pituitary-adrenal HPA system can become overactive, making a person more vulnerable to later stress

Question 12

Modern understanding of stress

Answer 12

• A modern definition of stress includes anything that risks triggering schizophrenia (Houston et al)
• Recent research has included cannabis as a risk factor
• It can increase the risk of schizophrenia by up to 7 times according to the dose
• It could be because cannabis interferes with the dopamine system
• But most people don’t develop SZ from smoking cannabis

Question 13

Treatment according to the interactionist model

Answer 13

• Acknowledges both biological and psychological factors
• Combines antipsychotic medication and psychological therapies like CBT

Question 14

Turkington et al

Treatment according to the interactionist model

Answer 14

shows that it is possible to believe in the biological cause of SZ and still benefit from CBT to relieve psychological symptoms.
* But must use interactionist model
* Cannot adopt purely biological approach because of psychological symptoms

Question 15

UK vs USA

Answer 15

In the UK, a combination of treatments is normally used. But this is not the case in the USA.

Question 16

Support for vulnerability and triggers

strength

Answer 16

• Large scale study by Tienari et al investigated impact of genetic vulnerability and psychological trigger
• 19,000 Finnish children whose biological mothers had SZ
• In adulthood, this group were compared to control group of adoptees without family history
• High levels of criticism, hostility and low levels of empathy parenting styles increase risk in genetic group
  Combination can increase stress to SZ

Question 17

Diathesis and stress are complex

limitiation

Answer 17

• The original model is hopelessly simplistic
• Multiple genes and combinations influence diathesis
• Stress can be biological and psychological
• Houston et al researched childhood sexual abuse emerged as the major influence on underlying vulnerability to SZ and cannabis as a major trigger
  Supports modern understanding

Question 18

RWA

strength

Answer 18

• Combining treatments enhances effectiveness
• Tarrier et al randomly allocated 315 participants to medication and CBT, medication and counselling, or control group of medication only
• Participants in the 2 condition groups showed lower symptoms but there was no difference in hospital readmission
  Clear practical advantage to adopting an interactionist approach to SZ

Question 19

counterpoint to RWA

Answer 19

• Jarvis and Okami point out that saying that a successful treatment for mental disorder justifies a particular explanation is the logical equivalent of saying that alcohol reduces shyness
• Logical error is called the treatment-causation fallacy
  Therefore we cannot automatically assume that the success of combined therapies means interactionist explanations are correct