Explaining Schizophrenia Flashcards
(7 cards)
What is the interactionist approach?
A broad approach to explaining schizophrenia that acknowledges that there are biological, psychological and societal factors in the development of schizophrenia.
What is the Diathesis Stress model?
An interactionist account to explaining behaviour. The Diathesis Stress model states that one or more underlying factors make a person vulnerable to developing schizophrenia but the onset of the conditioned is caused by a trigger.
What did the original diathesis stress model state?
In the original model the Diathesis was entirely genetic - the result of a ‘schizogene’ and the triggers were psychological. It was assumed that a person who carried the gene and suffered a significant psychological stress in childhood (usually as a result of parenting style in a dysfunctional family environment) could result in the development of the condition. The implication was that if a person did not have the schizogene, no amount of stress would lead to schizophrenia.
What is the modern understanding of the Diathesis Stress Model?
It is now clear that a number of genes appear to increase genetic vulnerability slightly; this is no single ‘schizogene’. It is also believed that trauma can be a Diathesis as well as genes. Early and severe trauma can seriously affect brain development - for example the hypothalamic pituitary adrenal (HPA) system can become over active, making the person more vulnerable to later stress.
Stress can include anything that triggers schizophrenia and can be psychological or biological in nature. In the Diathesis Stress model, cannabis is a stress factor as research has shown that high doses can trigger schizophrenia in people with a pre-existing vulnerability.
EVALUATION OF THE DIATHESIS STRESS MODEL
Is there any evidence to support it?
There is evidence to support the dual role of vulnerability and stress in the development of schizophrenia.
Tiernari et al investigated the combination of genetic vulnerability and parenting style. (Children with schizophrenic mothers adopted). The adoptive parents were assessed for child-rearing style, and the rates of schizophrenia compared to a control group of adoptees with no genetic risk. A child rearing style characterised by high levels of criticism and conflict and low levels of empathy was implicated in the development of schizophrenia.
This suggests that both genetic vulnerability and family-related stress are important in the development of schizophrenia as genetically vulnerable children are more sensitive to parenting behaviour.
This is very strong support for the importance of adopting an interactionist approach to schizophrenia, including hanging on to the idea that poor parenting is a possible source of stress.
EVALUATION OF THE DIATHESIS STRESS MODEL
Is there any evidence against the original Diathesis Stress Model?
The classic model of a single schizogene and schizophrenic parenting style is now seen as overly simple.
Evidence clearly shows that multiple genes increase vulnerability, each having a small effect on its own. Recent research has also shown that stress can come in many forms.
Houston et al found that childhood sexual trauma emerged as a vulnerability factor whilst cannabis use was a trigger.
This reinforces how the original model of biological Diathesis with psychological stress is overly simple. This is an issue for the original model but supports the modern model.
EVALUATION OF THE DIATHESIS STRESS MODEL
Do we know how diathesis and stress work?
A problem is that we don’t know exactly how Diathesis and stress work.
There is strong evidence to suggest some sort of underlying vulnerability coupled with stress can lead to schizophrenia. However, we do not yet fully understand the mechanisms by which the symptoms of schizophrenia appear and how both vulnerability and stress produce them.
This incomplete understanding means that most researchers have now abandoned the original model which only focuses on genetics and family environment. However, in doing so the fact that the exact source of vulnerability and stress is unknown makes it less easy to predict whether someone will develop schizophrenia.
