Interactionist Approach Schizophrenia

• The interactionist approach combines both biological and psychological explanations for schizophrenia.
• The diathesis-stress model suggests that behaviour is predetermined by biological factors and triggered by environmental influences.
• The interactionist approach is sometimes called the biosocial approach.
• The interactionist approach acknowledges that there are biological, psychological and social factors in the development of schizophrenia.
• Biological factors include genetic vulnerability, neurochemical and neurological abnormality.
• Psychological factors include stress from external sources such as life events or daily hassles.
• Social factors include family dysfunction and poor-quality interactions within the family.
• Brown & Birley (1968) investigated the life events of schizophrenic patients in the 12 weeks prior to their psychotic episode. They found that 50% of patients experienced a stressful event in the three weeks prior to the episode. This suggests that the stressful experience may have triggered the schizophrenic episode.
• Hirsch et al (1996) carried out a longitudinal study looking at the life events experienced by 71 schizophrenic patients over a period of four years. They found that the impact of stressful life events in the 12 months prior to a schizophrenic episode had a significant effect.
• Many studies have suggested that stress in the environment has impacted on the development of schizophrenic symptoms.
• The diathesis-stress model suggests that behaviour is predetermined by biological factors and triggered by environmental influences.
• An idea to explain the combination of biology and environment is called the diathesis-stress model.
• The diathesis-stress model suggests that both a biological vulnerability to schizophrenia and external stress triggers are necessary to develop the disorder.
• Meehl (1962) suggested that in the original diathesis-stress model the vulnerability to schizophrenia was entirely genetic, the result of a single 'schizogene'.
• According to Meehl (1962) if a person does not have the schizogene then no amount of stress would lead to schizophrenia.
• Ripke et al (2014) argue that there is no single gene for schizophrenia but that many genes appear to increase genetic vulnerability.
• On their own, biological risk factors do not trigger a psychotic episode, but with an environmental stressor such as family dysfunction or substance misuse, schizophrenia can be triggered.
• Ingram & Luxton (2005) have a modern view of the diathesis-stress model which includes a range of factors beyond the genetic such as psychological trauma.
• Barlow & Durand (2009) offer support for the diathesis-stress model, in that some people have a genetic vulnerability which can be triggered by the stress of a dysfunctional family. This interaction leads to the development of schizophrenia.
• Read et al (2001) proposed a neurodevelopmental model which claims that early trauma physically alters the developing brain. This can lead to an increased vulnerability for schizophrenia.
• The diathesis-stress model can be used to explain schizophrenia as it acknowledges an interaction between biology and the environment.
• The interactionist approach has been used to explain schizophrenia but can also be used when considering the treatment of schizophrenia.
• Hogarty et al (1986) looked at relapse rates of schizophrenia patients and found a rate of 41% with drug therapy alone, but with family therapy it improved to 19%.
• Sudak (2011) found that compliance with antipsychotic medication improved when patients were also given CBT. This highlights the benefit of an interactionist approach.
• Adopting an interactionist approach for the treatment of schizophrenia combines biological intervention such as antipsychotics, with psychological therapy such as CBT.
• Many research studies support the interaction of both antipsychotics and CBT for the treatment of schizophrenia.
• One strength of the interactionist approach is in the combination of biological and psychological treatments in the real-world application for schizophrenia.
• Studies show that combining treatments enhances their effectiveness in patients with schizophrenia.
• Sensky et al (2000) found that CBT has significant and lasting benefits even after nine months, for both positive and negative symptoms of schizophrenia. They found that CBT worked best when combined with antipsychotic medication.
• Turkington et al (2006) argue that it is perfectly possible to believe in biological causes of schizophrenia and still practise CBT to relieve psychological symptoms.
• In the UK it is standard practise to treat people with schizophrenia using a combination of antipsychotic drugs and CBT.
• In the USA it is less common to use an interactionist approach for treating schizophrenia. Medication is usually prescribed without accompanying psychological treatment.
• Tarrier et al (2004) randomly allocated 315 participants to either a medication and CBT group, a medication and counselling group, or a control group (medication only). They found that participants in the two combination groups showed lower symptoms than the control group.
• Tarrier et al (2004) suggest that there is a clear practical advantage to adopting an interactionist approach to schizophrenia in terms of more positive treatment outcomes.
• Tienari et al (2004) investigated the impact of both genetic vulnerability and a psychological trigger (dysfunctional parenting). They followed 19,000 children in Finland whose biological mothers had been diagnosed with schizophrenia. In adulthood this high genetic risk group were found to have a stronger association with the development of schizophrenia.
• One limitation of the diathesis stress model is over simplicity. There are so many environmental factors associated with the onset of schizophrenia as well as all the multiple genes which have been identified.
• Jarvis & Okami (2019) suggest caution when considering the interactionist approach and highlight an error called the treatment-causation fallacy. This is the mistake that just because a treatment is successful does not mean it justifies a particular explanation.
• By taking an interactionist approach, we can avoid issues such as the treatment causation fallacy. This is the assumption, that when using one treatment such as drugs, if symptoms are reduced, it is assumed that the cause is biological. This may not be the case.