PAPER 3 - SCHIZOPHRENIA - the interactionist approach to schizophrenia

Question 1

what is the interactionist approach?

Answer 1

• nature and nurture both play a role in explaining behaviour
• behaviour can be explained in terms of a range of biological & psychological factors

Question 2

what is the diathesis-stress model?

Answer 2

• used to represent interactionist approach
• explains mental disorders as the result of an interaction between biological (diathesis) and environmental (stress) influences that trigger a disorder

Question 3

who was the original diathesis-stress model proposed by?

Answer 3

Meehl (1962)

Question 4

what did Meehl propose about the original diathesis-stress model?

Answer 4

proposed there was a single schizogene and exposure to chronic stress through childhood (espeically presence of schizophrenogenic mother) made people vulnerable to the disorder

Question 5

how has the diathesis-stress model changed since Meehl?

Answer 5

• now understood that there are many genes which can increase genetic vulnerability
• also thought that psychological trauma can be diathesis rather than stressor (Read et al)

Question 6

what did Read suggest about the diathesis stress model?

Answer 6

neurodevelopmental model - early severe trauma can affect brain development making individuals vulnerable to stress

Question 7

what is additivity?

Answer 7

• there are several combinations of diathesis and stress
• e.g. huge vulnerability & small stress, small vulnerability & huge stress, middle vulnerability & middle stress

Question 8

what does “diathesis” mean?

Answer 8

• biological vulnerability
• Meehl thought it was a single schizogene
• now known as combination of genes
• psychological trauma = diathesis - MZ twins research findings support diathesis stress as they have a higher concordance rate than DZ twins for the disorder

Question 9

what does “stress” mean?

Answer 9

• environmental trigger
• can include childhood trauma
• people in high urbanised areas had more than 2x risk of getting SZ due to more adverse living conditions
• modern view: stressor includes anything that triggers a disorder e.g. drug use

Question 10

what was the AIM of the study by Tienari (2004)?

Answer 10

to test the hypothesis that genetics moderate susceptability to environmental stressors that are associated with adaptive family functioning

Question 11

what was the PROCEDURE of the study by Tienari (2004)?

Answer 11

• 20,000 records of women hospitalised in Finland 1960-1979 diagnosed at least once with SZ
• identified those who had 1 or more children adopted
• 145 adopted-away (high-risk group) was matched with 158 adoptees without this genetic risk (low-risk group)
• both groups were assessed after 12 then 21 years

Question 12

what were the FINDINGS of the study by Tienari (2004)?

Answer 12

• family functioning also assessed in adoptive families using the OPAS scale
• of the 303 adoptees, 14 developed SZ, 11 of which were from high-risk group (other 3 in low risk)
• ‘healthy’ adoptive family/low OPAS score = protected from SZ
• low risk adoptees with low OPAS score = much less likely to get SZ

Question 13

what are the criticisms of the Tienari (2004) study?

Answer 13

• assessments of adoptive family functioning by psychiatrists was only at one given point in time, therefore fails to see any developmental changes that may happen over time
• also difficult to assess source of stress when observing family interactions (is it coming from adoptees or adoptive family)

Question 14

what treatment is there according to the interactionist approach?

Answer 14

• combining antipsychotic medication and psychological therapies (commonly CBT)
• Turkington (2006) says its possible to believe in biological causes and relieve symptoms with CBT, but must adopt interactionist model

Question 15

evaluation - what evidence is there to support role of both vulnerability and triggers?

Answer 15

• Tienari - observing reciprocal interactions between adoptive family & adoptees makes it impossible to determine how much of the stress observed is assigned to the family/adoptees
• most diathesis stress models emphasise vulnerability in terms of genetic influence alone
• however, increased risk can also result from brain damage caused by environmental factors, researchers estimated risk of developing SZ later in life are 4x more likely if individual experienced birth complications
• findings suggest brain damage plays a role in development of SZ

Question 16

evaluation - what is the link between urbanisation and SZ?

Answer 16

• urban environments are necessarily more stressful - studies suggested living in urban environments was significant stress factor for SZ but not all research agreed
• researchers found no urban-rural differences in mental health in New Zealand
• other studies (although finding evidence for urban-rural differences) showed these differences disappeared after adjusting to socio-economic differences for the 2 groups
• suggests socio adversity may be a significant trigger

Question 17

evaluation - what is the treatment-causation fallacy?

Answer 17

• Turkington argue that there is a good logical fit between interactionist approach and using combination treatments
• however, the fact that combined biological & psychological are more effective doesnt mean interactionist approach is correct
• error of logic is called treatment-causation fallacy

Question 18

evaluation - why is the original diathesis-stress model considered to be an oversimplification?

Answer 18

• classic model of schizogene and schizophrenic parenting style is too simple
• multiple genes increase vulnerability to SZ, each having small effect of its own (no single schizogene) so vulnerability & stress don’t have one single cause
• vulnerability is a result of childhood trauma as well as genetic makeup, and that stress comes in many forms
• research found that cannabis and sexual childhood trauma were triggers

Question 19

evaulation - how can the interactionist approach be applied to the rea, world (treatment)?

Answer 19

• if the onset of SZ is a result of additive effect of genetic vulnerability & environmental stress, then there are implications for treatment
• researchers found that women infected with cyrimegalovirus during pregnancy were more likely to have a child develop SZ (only if mother and child both carried gene defect)
• suggests antiviral medicne during pregnancy may prevent onset of SZ in offspring

Question 20

what is genetic screening for vulnerability?

Answer 20

e.g. if mother & unborn baby both have vulnerabiliyu, we could give antiviral medication during pregnancy