interactionist approach

• Interactionist approach ?

  A way to explain the development of behaviour in terms of a range of factors, including both biological and psychological ones. Most importantly such factors don't simply add together but combine in a way that can't be predicted by each one separately i.e. they interact.
• Diathesis-stress model ?

  An interactionist approach to explaining behaviour. For example schizophrenia is explained as the result of both an underlying vulnerability (diathesis) and a trigger (stressor), both of which are necessary for the onset of schizophrenia. In early versions of the diathesis-stress model, vulnerability was genetic and triggers were psychological. Nowadays both genes and trauma are seen as diatheses, and stress can be psychological or biological in nature.
• one strength of the interactionist approach to schizophrenia?

  P - evidence supporting the role of both vulnerability and triggers.

  E - Tienari et al. (2004) investigated the impact of both genetic vulnerability and a psychological trigger. The study

  falowed 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 history of schizophrenia.

  Adoptive parents had been assessed for child-rearing style and it was found that 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.

  L - combination of genetic vulnerability and family stress can lead to greatly increased risk of schizophrenia.
• One limitation of the original diathesis-stress model ?

  P - over-simplicity.

  E - clear that the original model that portrayed diathesis as a single schizogene and portrayed stress as schizophrenogenic parenting is hopelessly simplistic. Multiple genes in multiple combinations influence diathesis. Stress also comes in many forms, including but not limited to dysfunctional parenting. In fact diathesis can also be influenced by psychological factors and stress can be biological as well as psychological. This is shown in a study by Houston et al. (2008), in which childhood sexual abuse emerged as the major influence on underlying vulnerability to schizophrenia and cannabis use as the major trigger.

  L - multiple factors, both biological and psychological, affecting both diathesis and stress, supporting the modern understanding of both diathesis and stress.
• One further strength of the interactionist approach ?

  P - combination of biological and psychological treatments.

  E - A practical application of acknowledging biological and psychological factors in schizophrenia has been the combination of drug treatment and psychological therapies. Studies show that combining treatments enhances their effectiveness.

  For example Tarrier et al. (2004) randomly allocated 315 participants to

  (2) medication + CBT, (2) medication + counselling, or (3) control group (medication only). Participants in the two combination groups showed lower symptoms following the trial than the medication-only group, though there was no difference in hospital readmission.

  L - clear practical advantage to adopting an interactionist approach to schizophrenia in terms of superior treatment outcomes.
• CA for one further strength of interactionist approach ?

  P - Jarvis and Okami (2019) point out that saying that a successful treatment for mental disorder justifies a particular explanation is the logical equivalent of saying that because alcohol reduces shyness, shyness is Caused by lack of alcohol. This logical error is called the treatment-causation fallacy.

  L - cannot automatically assume that the success of combined therapies means interactionist explanations are correct.
• Meehl's model?

  In the original diathesis- stress model diathesis (vulnerability) was entirely genetic, the result of a single schizogene. led to the idea of a biologically based schizotypic personality, one characteristic of which is sensitivity to stress. According to Meehl, if a person does not have the schizogene then no amount of stress would lead to schizophrenia. However, in carriers of the gene, chronic stress through childhood and adolescence, in particular the presence of a schizophrenogenic mother, could result in the development of the disorder.
• modern understanding of diathesis?

  now clear that many genes each appear to increase genetic vulnerability only slightly, there is no single schizogene (Ripke et al. 2014). also include a range of factors beyond the genetic, including psychological trauma - 0 trauma becomes the diathesis rather than the stressor. Read et al. (2001) proposed a neurodevelopmental model in which early trauma alters the developing brain. Early and severe enough trauma, such as child abuse, can seriously affect many aspects of brain development. For example the hypothalamic-pituitary-adrenal (HPA) system can become overactive, making a person much more vulnerable to later stress
• Modern understanding of stress ?

  a modern definition of stress includes anything that risks triggering schizophrenia (Houston et al. 2008). Much of the recent research into factors triggering an episode of schizophrenia has concerned cannabis use. cannabis is a stressor because it increases the risk of schizophrenia by up to 7 times according to dose as cannabis interferes with the dopamine system. However, most people do not develop schizophrenia after smoking cannabis presumably as they lack the requisite vulnerability factors