An Interactionist Approach Flashcards
An interactionist approach is one that sees schizophrenia as the result of an interaction between
Biological and psychological/environmental factors
Biological factors could include
Genetics
Brain abnormalities
DA hypothesis (high activity)
Psychological/environmental factors could include
Family: schizophenogenic mother, double bind and expressed emotion
Urban living
The diathesis stress model
This is an example of an interactionst approach to explaining schizophrenia
Diathesis refers to vulnerability and Stress refers to a negative experience that triggers the disorder
Therefore, the model proposes that schizophrenia develops if an individual is biologically at risk of the disorder and has had a negative experience that triggers the disorder to manifest
The original diathesis-stress model by Meehl (1962) proposed that the “diathesis” was entirely genetic
Meehl stated that possession of a single schizogene resulted in a schizotypic personality (an individual who is highly sensitive to stress)
Twin study evidence indeed suggests a genetic component because
40% concordance rates for MZ 7% DZ suggests genetic component because more similarity, higher rate
Furthermore, twin study evidence also suggests that the cause is not entirely genetic because
Concordance rates for identical twins were 40% which should be 100% if the cause was entirely genetic
Meehl’s model therefore proposed that “stress” also is necessary to trigger the disorder
that “stress” was entirely environmental
Dysfunctional parenting during childhood/adolescence in an individual with the ‘schizogene’ would trigger the development of the disorder
in particular, the presence of a schizophregenic mother
Other research suggests that living in densely populated, urban environments more than doubles the risk of schizophrenia (Vassos et al)
possibly due to adverse living conditions
This evidence again suggests an interaction of diathesis and stress, because
not everyone living in urban environments develops the disorder since not all will possess genetic vulnerability
The model assumes additivity
that diathesis and stress add together in some way to produce the disorder
There are several ways that the two could combine and lead to the onset of the disorder
more of one requires less of the other
implications for treatment
Because the model acknowledges both biological and psychological factors in schizophrenia, it is compatible with both biological and pyschological treatments.
In particular, the model is associated with combining the use of antipsychotic medication with CBT
It is unusual to treat schizophrenia using psychological therapies alone; in fact, CBT, family therapy and token economies are usually carried out with patients who are also prescribed antipsychotics
Supported by evidence from prospective studies
Tienari et al 19000 adopted children, biological mothers with schiz and a control group with healthy mothers
Most likely to develop were those with biological mothers with schiz and adoptive parents with child rearing styles including high level critism low level Empathy
Increases validity showing schiz most likely to devlop from combiniation of stress and genetic vulnerability
Supported by evidence from the effects of treatment
Tarrier
patients who were given combined treatments (cbt+antipsychotics) had lower levels of symptoms than those who had recieved antipsychotics alone
increases validity, combination of treatments effective, combinition of factors is the cause
however treatment causation fallacy
over simplified
It is now believed that there is no single ‘schizogene’ as originally proposed by Meehl, but rather there are multiple genes that increase vulnerability to schizophrenia.
diathesis may not be genetic ie early trauma can affect brain development, making them more susceptible to later stress
stress may not be environmetal eg cannabis smoking interferes with the DA system can increase the risk of schiz
reduces the validity of the original model, may not be what meehl first suggested (revised models rectified this)
incomplete
While there is strong evidence to suggest that an underlying vulnerability coupled with stress can lead to schizophrenia, we do not yet fully understand how this combination of factors work together to produce the symptoms.
reduces credibility of model, implies an unsatifisfactory explanation for schiz
