Specification: The importance of an interactionist approach in explaining and treating schizophrenia; the diathesis-stress model.

The importance of using an interactionist approach to explain schizophrenia

The interactionist approach involves taking into consideration both biological and psychological factors in the development of schizophrenia. This approach acknowledges that a range of factors are involved in the illness and encompasses the diathesisstress model, where it is thought that schizophrenia is caused by a combination of biological and environmental factors. Schizophrenia is seen to be triggered when environmental stress combines with a biological vulnerability. 

The word diathesis means vulnerability, and in this context, stress means psychological experience. Therefore, the diathesis-stress model argues that both a vulnerability to schizophrenia (through genetics for example) and a stress trigger (say dysfunctional family dynamics) are necessary for schizophrenia to develop. Many factors, such as genetics or biochemistry can make a person vulnerable, but they will not develop schizophrenia without stress. 

Lots of research has indicated that schizophrenia has a biological component, either through genes or biochemistry. Several genes have been identified to increase vulnerability and having a relative with the illness increases a person’s risk. Also, it is likely that genetic factors are linked to faulty dopaminergic systems and possible abnormal functioning in other neurotransmitters. However, the diathesis-stress model argues that biology alone does not cause the illness. Instead, biological vulnerability increases the risk that environmental stressors can trigger schizophrenia. 

Understanding ‘Diathesis’: It is now understood that there is no single ‘schizogene’ and that many genes appear to increase vulnerability (Ripke et al. 2014). Read et al. (2001) argue that diathesis now includes a range of factors such as psychological trauma in the form of child abuse. It has been proposed that early psychological trauma alters an infant’s developing brain and causes vulnerability, as the hypothalamic-pituitary-adrenal (HPA) system becomes overactive, making the person more vulnerable to stress. 

Understanding ‘Stress’: The original diathesis-stress model argues that stress is psychological in nature, and in the context of schizophrenia it was caused by dysfunctional family dynamics. Nowadays a broader definition has been adopted and refers to anything that risks triggering schizophrenia; cannabis use for example (Houston et al. 2008), can be a stressor as it disrupts the body’s dopamine system. 

Evaluation

There is research evidence to support the interactionist approach to explaining schizophrenia. Barlow and Durand (2009) found that a family history of schizophrenia pointed to a genetic link. When combined with a dysfunctional family the risk of developing schizophrenia increased. This supports the diathesis-stress model as the increased risk was due to an interaction of genetics and stress from the family dynamic. Further support comes from Cannon et al. (2002) who found a positive correlation between birth complications and a later risk of schizophrenia due to damage to the hormone and neurotransmitter systems. Again this supports an interaction between biological vulnerabilities and later stressors. 

The diathesis-stress model proposes that schizophrenia is caused by a combination of biology and environment. However, it is not known precisely how these risk factors i.e. how biological, environmental, psychological and social factors, contribute to the diathesis-stress interaction, as the causes may differ between individual schizophrenics. This approach is weakened as we do not fully understand the mechanisms by which the illness develops and how both vulnerability and stress produce it. 

Critics have argued that the original diathesis-stress model is over simplistic, e.g. the idea that a single gene combined with a certain parenting style causes the schizophrenia is too simplistic. Multiple genes have been found to increase the risk of developing the illness indicating that there is no single ‘schizogene’. Also, stress is not limited to just parenting style and family dynamics. More recent research by Houston et al. (2008) found that vulnerability is not limited to biology by finding that childhood sexual trauma increased the risk of developing the illness when the patient later used cannabis. Therefore, proposing that vulnerability and stress have one single cause and that each comes in one form i.e. vulnerability being biological and stress being environmental, like the original model proposes, is dated and over simplistic. 

The importance of using an interactionist approach to treat schizophrenia

A wealth of research has been conducted into the efficiency of different treatments for schizophrenia. However, some research (Guo et al. 2010) has indicated that combining treatments, both biological and psychological, is more effective. However, it is difficult to state which combination is superior as it is affected by each patient’s circumstances and needs. For example, there is little point in combining drugs with family therapy if the patient has little contact with their relatives. In Britain, antipsychotic drugs are usually given first to reduce the patient’s symptoms so that any psychological treatment provided, usually in the form of CBT, has a better chance of being engaged with. It is unusual for a person with schizophrenia to be offered a psychological therapy alone. The USA doesn’t tend to adopt an interactionist approach and instead typically offers medication without any psychological treatments. It is rare for either country to offer a psychological treatment like CBT, without the use of medication. 

Turkington et al. (2006) argue that it is possible to think that schizophrenia is caused by biology and still offer a psychological treatment, as in doing so an interactionist approach has been adopted as both the biological and psychological symptoms are being treated. However, it makes little sense to argue that schizophrenia is purely biological in origin and that there is no psychological meaning to their symptoms, but then offer a psychological treatment. When adopting an interactionist approach to the treatment of schizophrenia, we are acknowledging the influence of diathesis and stress in causing the illness. 

Evaluation

There is research evidence that supports an interactionist approach to treating schizophrenia. Guo et al. (2010) found that patients who received a combination of antipsychotics and a psychological therapy whilst in the early stages of schizophrenia had improved insight and social functioning as well as being less likely to relapse when compared with patients taking antipsychotics alone. This illustrates the value of combining biological and psychological treatments. 

Combining treatments does not always have a positive effect. It has been found that patients receiving CBT can sometimes interpret the side effects of their antipsychotic drugs in a delusional manner. This then led to them mistrusting and resisting any further treatment, indicating that combining treatments can cause further problems. 

Combining treatments can be cost-effective. Schizophrenia often has biological and psychological components and therefore treatment via a combination is desirable. The antipsychotics treat the biological elements, and the psychological treatments tackle the psychological elements. Although combining treatments increase the initial cost of treatment, as the effectiveness increases i.e. patients get better quicker and stay better for longer, the combination works out more cost effective in the long-run as both the biological and psychological elements are addressed. 

Critics argue the logic of the interactionist approach to treating schizophrenia. Turkington et al. (2006) argue that whilst research has found that combining biological and psychological treatments is more effective than them on their own, this does not necessarily support the interactionist approach. This is called the treatment-causation fallacy, as we cannot be certain whether it is the interaction of the treatments which is causing the increased efficiency. 

Possible exam questions

1. Outline the interactionist approach to explaining and/or treating schizophrenia. (6 marks)

2. Describe one study in which the interactionist approach to schizophrenia has been explained. (5 marks)

3. People with schizophrenia can be treated using drugs, CBT or a combination of both.
   Briefly discuss one reason why it might be preferable for a person with schizophrenia to be treated using both drugs and CBT. (3 marks)

4. Briefly discuss the advantage of using an interactionist approach to explaining schizophrenia. (8 marks)

5. Discuss interactionist explanations for schizophrenia. (16 marks)

6. Describe and evaluate therapies using an interactionist approach for the treatment of schizophrenia. (16 marks)

7. Stephan has been diagnosed with schizophrenia. He is not keen on being treated with drugs because he has heard there may be unpleasant side effects. His doctor discusses his options and suggests an interactionist approach to treatment.
   Discuss the advantages and disadvantages of using this approach to treat someone with schizophrenia. (16 marks)