The interactionist approach to schizophrenia

Question 1

What is the interactionist approach to SZ?

Interactionist approach to SZ

Answer 1

A way to explain development of behaviour in terms of biological, psychological and social factors.
Factors don’t simply add together but combine in a way that can’t be predicted by each one seperately - they interact

Question 2

What are biological factors?

Interactionist approach to SZ

Answer 2

Genetic vulnerability
Neurochemical and neurological abnormality

Question 3

What are psychological factors?

Interactionist approach to SZ

Answer 3

Stress resulting from life events and daily hassles

Question 4

What is the diathesis-stress model?

Interactionist approach to SZ

Answer 4

A way of presenting the interactionist approach
Both a vulnerability to SZ and a stress-trigger are necessary to develop disorder

Question 5

Meehl’s Model (1962)

Interactionist approach to SZ

Answer 5

OG diathesis-stress model
Diathesis was entirely genetic, result of a single ‘schizogene’
Led to idea of biologically based schizotypic personality
According to Meehl, if a person doesn’t have schizogene no amount would lead to SZ
In carriers of gene, chronic stress through childhood, particularly presence of schizophrenogenic mother, could result in development of SZ

Question 6

How has our understanding of diathesis changed?

Interactionist approach to SZ

Answer 6

Many genes each appear to increase genetic vulnerability - no single schizogene (Ripke et al 2014)
Diathesis can be psychological trauma (Ingram and Luxton, 2005)

Question 7

Read et al’s (2001) neurodevelopmental model

Interactionist approach to SZ

Answer 7

Early and severe enough trauma (child abuse) can affect brain development
E.g. hypothalamic-pituitary-adrenal (HPA) system can become overactive, making a person more vulnerable to later stress

Question 8

How has our understanding of stress changed?

Interactionist approach to SZ

Answer 8

Stress includes anything that risks triggering SZ (Houston et al 2008)
Cannabis is a stressor as it increases risk of SZ by up to 7x accoridng to dose
May be because cannabis interferes with DA system
Most people do not develop SZ after smoking cannabis because they lack vulnerability factors

Question 9

How to treat SZ according to the interactionist model?

Interactionist approach to SZ

Answer 9

Combining antipsychotic medication with psychological therapies, most commonly CBT

Question 10

Turkington et al (2006) views on treatment with interactionist model

Interactionist approach to SZ

Answer 10

Possible to believe in bio cause of SZ and still practise CBT to relieve psycho symps
Requires adopting interactionist model
Not possible to adopt purely bio approach and tell people with SZ that the condition is purely bio and there is no psycho significance to symps and then treat them with CBT

Question 11

Common treatment for SZ in UK vs US

Interactionist approach to SZ

Answer 11

UK - combo of antipsychs and CBT
US - history of conflict between psycho and bio models of SZ
Slower adoption of interactionist approach
Medication without psycho treatment more common in US

Question 12

Support for vulnerability and triggers

Interactionist approach to SZ

Answer 12

Tienari et al (2004) - large scale study investigated impact of both genetic vuln and psycho trigger (dysfunc parenting). 19,000 Finnish kids whose bio mothers had SZ
In adulthood high genetic risk group were compared to control group of adoptees with no fam history of SZ
Adoptive parenst assessed for child-rearing style
Found high levels of criticism, hostility and low levels of empathy were strongly associated with development of SZ but only in high risk group
Therefore, combo of genetic vuln and fam stress can lead to increased risk of SZ

Question 13

Diathesis and stress are complex

Interactionist approach to SZ

Answer 13

Limitation
OG d-s model is simplistic
Multi genes in multi combos influence diathesis
Stress also comes in many forms
Houston et al (2008) - childhood sex abuse emerged as major influence on underlying vuln to SZ and cannabis and major trigger
Therefore, there are multi factors (bio & psycho) affecting boyh diathesis and stress, supporting modern understanding of both diathesis and stress

Question 14

Real-world application

Interactionist approach to SZ

Answer 14

Strength
Combo of drug treatment and psycho therapies enchances effectiveness
Tarrier et al (2004) randomly allocated 315 ppts to (1) medication & CBT, (2) medication & councelling, or (3) medication only (control).
Ppts in combo groups showed lower symps following trial that control group
No difference in hospital readmission
Therefore, clear practical advantage to adopting interactionist approach in terms of superior treatment outcomes

Question 15

Counterpoint - Real-world application

Interactionist approach to SZ

Answer 15

Jarvis & Okami (2019) - saying that a successful treatment for a mental disorder justifies a particular explanation is illogical (shyness is caused by lack of alcohol)
Treatment-causation fallacy
Therefore, we cannot automatically assume the success of combined therapies means interactionist explanations are correct

Question 16

Urbanisation

Interactionist approach to SZ

Answer 16

SZ more commonly diagnosed in urban than rural areas
Stat used to justify interactionist position as it assumes urban living is more stressful - city acts as trigger
However, may be that SZ is more likely diagnosed in cities or people with diathesis for SZ tend to migrate to cities