sz - The importance of an interactionist approach in explaining and treating schizophrenia Flashcards
outline the interactionist approach to SZ?
The diathesis stress model suggests that schizophrenia results from an interaction between genetic vulnerability and environmental stress. In other words, environmental stress is required to trigger the disorder in those so disposed. One version of the diathesis stress model (Zubin & Spring, 1977) theorises the relationship like this:
(GRAPH)
What does this graph suggest about the nature of the interaction between vulnerability and stress in schizophrenia?
Most likely to have SZ when you have high vulnerability and high stress
outline the diathesis stress model?
The interactionist approach encompasses the diathesis stress model where schizophrenia is perceived as resulting from a combination of biological and environmental factors. A schizophrenic episode is seen as being triggered or worsened when environmental stressors combine with biological diathesis (vulnerability).
Research indicates SZ has a biological component, with several genes and faulty dopaminergic systems increasing vulnerability to developing the disorder. However in about 50% of identical twins in which one twin is diagnosed with SZ, the other never meets the diagnostic criteria for SZ. This discordance indicates that environmental factors must play a role in determining whether a biological vulnerability actually develops into a disorder.
explain a study into stress as a cause of SZ?
Varese et al. (2012) found that children who experienced extreme trauma before age 16 were 3X as likely to develop SZ in later life compared with the general population. In addition the risk for SZ in most urban environments were found to be 2.37 X higher than most rural environments. Although the link may not be clear, this may be due to the adverse conditions of living in a densely populated area.
Lots of crime
Lots of pollution
Lots of traffic
Lack of green open space
What type of socio-economic status might be associate with adverse conditions of living in a densely populated area?
Often associated with low economic status
However there are exceptions to this rule as there are lots of regeneration and luxury
what does pedersen and mortensen show about urbanicity and SZ?
This shows a positive correlation between urban density and relative risk of SZ
There may be a third variable of low socio-economic status
what does the tienari et al research tell us about family stress and sz?
Suggests that both the high and low risk samples were more likely to develop SZ in a severely disturbed family than a mildly disturbed family and healthy family.
Children are most likely to get SZ when they are in a severely disturbed family and are high risk to develop SZ. The severely disturbed family represents a highly expressed emotion environment in which this triggers the high risk children to develop SZ.
Those In a mildly disturbed family with high risk are more likely to develop SZ than a severely disturbed low risk. This suggests that the genetic factors is more weighted than environment.
Low risk in healthy family greater level of disturbance than high risk. This contradicts diathesis stress as we would expect high risk to have greater levels of diturbance than low risk.
study that backs up the fact that low socio economic status is a third variable?
Paykel et al. (2000) found that urban-rural differences do occur, however these differences disappear after adjusting for the socio-economic differences between the 2 groups.
Backs up the fact that low socio economic status is a third variable
study into cortisol levels and sz?
Walker (1997) reported that SZs have higher levels of cortisol than non-suffers and that cortisol levels are related to the severity of symptoms, with stress-related increases in cortisol levels heightening genetic-influenced abnormalities in dopamine transmission that underpin vulnerability to SZ.
This study supports the interactionist approach to SZ as it suggests that stress, an environmental trigger can cause increased levels of cortisol. Heightened levels of cortisol increases genetic-influenced abnormalities in dopamine transmission that underpin vulnerability to SZ
However cortisol is also released from the body during exercise, which is a positive stress and could actually improve mental health
Therefore we cannot make the link between cortisol and development of SZ
explain the difficulties in determining causal stress?
Diathesis stress model typically references stress that occurs close to the onset of SZ, however it is possible that earlier stressors can influence how people respond to stress later in life
Eg maladaptive methods of coping with stress in childhood means an individual fails to develop coping skills which comprises their resilience
Practical application: if we know someone has a vulnerability we can teach them coping mechanisms in order to reduce the stress
explain the Implications for treatment
Although we can’t control genetic vulnerability,
If we know someone has genetic vulnerability, we can take preventative measures to reduce the likelihood of triggering it
Borglum et al. (2014) found women with cytomegalovirus during pregnancy were more likely to have a child who developed SZ, but only if mother and child carried a particular gene defect
explain what treatments would be suggested by the interactionist approach?
Would this approach suggest combination treatments where more than one treatment is delivered simultaneously, or singular treatments to be more effective? Discuss in relation to individual differences.
Interactionist approach acknowledges both bio (eg dopamine) and psychological factors (eg negative expressed emotion) in SZ so is compatible with both treatments
Take into account individual needs – eg family therapy if they have dysfunctional family relationships
But generally antipsychotics are given first to reduce symptoms so the psychological treatments will have a greater effect (CBT)
study into medication AND CBT?
Tarrier et al. (2004) 315 patients were randomly allocated to medication and CBT, medication and supportive counselling or medication only (control).
Patients in the combination groups showed lower symptom levels than those in the control although there was no difference in hospital readmission.
This shows, that addressing both biological and psychological factors reduces symptoms more than just medication only. However the fact there was no difference in hospital readmission suggests that relapse rates are very similar and therefore a combination of treatments may be less cost effective than just one treatment (the control)
study to evaluate combination of therapies?
HOWEVER
Guo et al (2010) reported that patients in the early stages of SZ who receive a combination of antipsychotics and psychological therapy have improved insight, quality of life and social functioning and are therefore less likely to discourage treatment or relapse compared with those taking antipsychotics alone.
However, maybe it actually is cost effective to provide a combination of treatments because this study suggests that relapse rates will be lower as they have improved insight and are less likely to relapse.
limitations of CBT?
Patients receiving CBT sometimes misinterpret the side effects of simultaneous drug treatment in a delusional manner, increasing their mistrust and resistance to further treatment.
There is a good logical fit between the interactionist approach and using combination treatments . However the fact that the combined ones are more effective does not mean that the interactionist approach is correct. Similarly the fact that drugs help does not mean the SZ is of a biological origin. This error of logic is called the treatment-causation fallacy.
So maybe it is one of the two treatments is working and the other is not
3rd variable problems such as one of the treatments is a placebo
