The Interactionist Approach to Schizophrenia

• What does the diathesis-stress model suggest about behavior?

  Behavior is caused by vulnerability expressed with stressors
• What was Meehl’s (1962) model primarily based on?

  Genetics
• What does schizophrenia result from according to Meehl’s model?

  A 'schizogene'
• How does chronic stress relate to the 'schizogene'?

  It can lead to developing schizophrenia in carriers
• What is the modern understanding of diathesis regarding genes?

  Many genes increase vulnerability; no 'schizogene'
• How can trauma affect vulnerability in the modern understanding of diathesis?

  Trauma can become the vulnerability instead of stressors
• What did Read et al (2001) propose about early trauma?

  It alters brain development significantly
• What is considered a stressor in relation to schizophrenia?

  Anything that risks triggering schizophrenia
• How much can drugs increase the risk of schizophrenia?

  Up to 7 times the dose
• Why are drugs considered stressors for schizophrenia?

  They interfere with the dopamine system
• Why do most cannabis smokers not develop schizophrenia?

  They likely lack vulnerability factors
• What does the Interactionist Model suggest about treatment?

  Both biological and psychological treatments are compatible
• What combination of treatments is associated with the Interactionist approach?

  Antipsychotic medication and psychological therapies
• What did Turkington et al (2006) highlight about Cognitive Behavioral Therapy?

  It can be practiced alongside biological causes belief
• What did Tienari et al (2004) study reveal about adopted children?

  Higher risk of schizophrenia with a schizophrenic mother
• What factor increased the risk of schizophrenia in Tienari et al's study?

  High verbal criticism and lack of empathy
• What practical application arises from acknowledging biological and psychological factors?

  Combination of drug treatment and psychological therapies
• What did Tarrier et al (2004) find about treatment groups?

  Combination groups showed lower symptoms
• What is the treatment-causation fallacy according to Jarvis & Okami (2019)?

  Assuming treatment success proves explanation correctness
• Why is the original diathesis model considered overly simplistic?

  Multiple genes influence diathesis, not just one
• How can psychological factors influence diathesis?

  They can also affect vulnerability
• How can stress be characterized in relation to schizophrenia?

  It can be both biological and psychological
• What is a limitation for the Interactionist Approach?

  Treatment-Causation Fallacy

  • Jarvis & Okami (2019) point out that saying a successful treatment for a mental disorder justifies a particular explanation is the logical equivalent of saying that because alcohol reduces shyness, shyness is due to a lack of alcohol
  •  This logical error is called the treatment-causation fallacy
  • Therefore we can not automatically assume that the success of combined therapies means interactionist explanations are correct
• What is a limitation for the Interactionist Approach?

  Diathesis & Stress are Complex

  • It is now clear that the original model that portrayed diathesis as a ‘schizogene’ is overly simplistic, as multiple genes in multiple combinations influence diathesis
  • Housten et al (2008) shows diathesis can also be influenced by psychological factors and stress can be both biological and psychological
  • This means that there are multiple factors, both biological and psychological, affecting both diathesis and stress, supporting the modern understanding of both diathesis and stress
• What is a strength for the Interactionist Approach?

  Real-World Application

  • A practical application of acknowledging biological and psychological factors in schizophrenia has been the combination of drug treatment and psychological therapies
  • Tarrier et al (2004) randomly allocated 315 participants to 3 groups of medication and cognitive behavioural therapy, medication and counselling or only medication, and participants in the two combination groups showed lower symptoms compared to the control
  • This means that there is a clear practical advantage to adopting an interactionist approach to schizophrenia in terms of superior treatment outcomes
• What is a strength for the Interactionist Approach?

  Support for Vulnerability & Triggers

  • Tienari et al (2004) compared 19,000 Finnish adopted children who had biological mothers with schizophrenia to a control of adoptees with no family history of schizophrenia
  • Those who had a schizophrenic mother had a higher risk of developing schizophrenia compared to the control group, if the child-rearing styles included high verbal criticism and lack of empathy
  • Therefore, this study raises the credibility of the interactionist approach, as it shows the relationship between the diathesis and stress