the interactionist approach to schizophrenia Flashcards
what is the interactionist approach?
- explaining the development of behaviour in terms of biological, psychological and social factors
- these factors combine in a way that can’t be predicted by each one separately
what are some biological factors that contribute to the development of schizophrenia?
- genetic vulnerability
- neurochemical and neurological abnormality
what are some psychological factors that contribute to the development of schizophrenia?
stress from life events and daily hassles
what are some social factors that contribute to the development of schizophrenia?
poor quality interaction in the family
what does the diathesis-stress model mean?
- diathesis = vulnerability
- stress = negative experience which acts as the triger
- both parts are necessary to develop the disorder
- one or more underlying factors make a person particularly vulnerable to developing schizophrenia but the onset of the condition is triggered by stress
describe meehl’s diathesis-stress model (1962)
- diathesis is entirely genetic, the result of a single ‘schizogene’
- idea of a biological based schizotypic personality
- one characteristic of this ‘personality’ is sensitivity to stress
- if a person does not have the schizogene then no amount of stress would lead to schizophrenia
- in carriers of the gene, chronic stress through childhood and adolescence, particularly in the presence of a schizophrenogenic mother, could result in the development of the disorder
modern understanding of diathesis: ripke et al. (2014)
- many genes each appear to increase genetic vulnerability only slightly (polygenic)
- no single ‘schizogene’
modern understanding of diathesis: ingram and luxton (2005)
- diathesis includes a range of factors beyond genetic, including psychological trauma, which then creates a physiological vulnerability
- trauma becomes diathesis rather than stressor
modern understanding of diathesis: read et al. (2001)
early trauma, such as child abuse, affects many aspects of brain development
modern understanding of diathesis: HPA system
hypothalamic-pituitary-adrenal (HPA) system can become overactive, making a person much more vulnerable to later stress
modern understanding of stress: houston et al. (2008)
- psychological stress from parenting is still considered important
- modern definition includes anything that risks triggering schizophrenia
modern understanding of stress: cannabis
- increases risk of schizophreniaby up to 7x
- may be because cannabis interferes with the dopamine system
- most people do not develop schizophrenia after smoking cannabis because they lack the requisite vulnerability factors
how can treatment be adapted according the interactionist model?
by combining antipsychotic medication and psychological therapies eg. CBT
treatment according to the interactionist model: turkington et al. (2006)
suggests it is perfectly possible to believe in biological causes of schizophrenia and still practise CBT to relieve psychological symptoms, but this requires adopting an interactionist model
how does the use of combined therapy differ between the UK and US?
- in the UK, it is increasingly standard practice to treat people with a combination of antipsychotic drugs and CBT
- in the US there is more of a hisotry of conflict between psychological and biological models of schizophrenia, which may have led to slower adoption of an interactionist approach
- medication without an accompanying psychological treatment is more common in the US than in the UK
evaluation: evidence supporting role of both vulnerability and triggers (tienari et al. 2004)
- investigated impact of both genetic vulnerability and a psychological trigger (dysfunctional parenting)
- followed 19,000 finnish children whose biological mothers had been diagnosed with schizophrenia
- in adulthood, this high genetic risk group were compared to a control group of adoptees without a family of schizophrenia
- adoptive parents had been assessed for child-rearing style
- high levels of criticism, hostility and low levels of empathy were strongly associated with the development of schizophrenia, but only in the high genetic risk group
- combination of genetic vulnerability and family stress leads to greatly increased risk
evaluation: orignial diathesis-stres model is oversimplified (houston et al. 2008)
- childhood sexual abuse emerged as the major influence on underlying vulnerability to schizophrenia and cannabis use as the major trigger
- multiple factors, both biological and psychological, affecing both diathesis and stress, supporting the modern understanding of both diathesis and stress
evaluation: real-world application in combination of biological and psychological treatments (tarrier et al. 2004)
- randomly allocated 315 ps to (1) medication + CBT, (2) medication + counselling, or (3) control group, medication only
- ps in two combination groups showed lower symptoms following trial than medication-only group
- no different in hospital readmission
- clear practical advantage of interactionist approach due to superior treatment outcomes
evaluation: flawed correlations (jarvis and okami 2019)
- saying a successful treatment for a mental disorder justifies a paritcular explanation is a logical error (treatment-causation fallacy)
- cannot automatically assume the success of combined therapies means interactionist explanations are correct
evaluation: urbanisation
- schizophrenia is more commonly diagnosed in urban than rural areas
- statistic is sometimes used to justify the interactionist position, assuming that urban living is more stressful than rural so city living acts as a trigger
- however, it many simply be that schizophrenia is more likely to be diagnosed in cities
- people with a diathesis for schizophrenia tend to migrate to cities
