AO3 - Biological Explanations Schizophrenia

• Family, twin and adoption studies must be considered cautiously because they are based on retrospective information and diagnosis may be biased by knowledge that other family members have also been diagnosed.
• It is important to recognise that genetics are only partly implicated in the development of schizophrenia as concordance rates are never 100%. If genes were the only cause identical twins would have 100% concordance rates.
• One limitation of the genetic explanation of schizophrenia is the problem of nature versus nurture. It is very difficult to separate out the influence of nature-v-nurture. As concordance rates are not 100%, it cannot be assumed that schizophrenia is wholly explained by genes.
• The UK Genome Project (2012) has increased our understanding of the complexity of the genetic influence on behaviour. It is now recognised that genes have multiple functions and it is suggested that schizophrenia is a multi-factorial trait.
• When considering the genetic explanation of schizophrenia it is important to recognise issues of generalisation in twin studies.
• The interactionist approach suggests that a combination of nature and nurture may be responsible for the development of disorders. The diathesis stress model claims that people are born with a biological predisposition which is triggered by environmental stressors resulting in subsequent disorders.
• The diathesis stress model claims that people are born with a biological predisposition which is triggered by environmental stressors and results in subsequent disorders.
• In family studies members share aspects of their environment as well as many of their genes which makes it difficult to identify the underlying cause of schizophrenia.
• One limitation of the genetic explanation for schizophrenia is that there is clear evidence to show that environmental factors also increase the risk of developing the disorder.
• Biological risk factors include birth complications as studied by Morgan et al (2017), as well as smoking THC-rich cannabis in teenage years (Di Forti et al, 2015).
• Psychological risk factors such as childhood trauma can leave people more vulnerable to adult mental health problems and the development of schizophrenia.
• Morkved et al (2017) found 67% of people with schizophrenia and related psychotic disorders reported at least one childhood trauma compared to 38% in a control group.
• One practical application of our understanding of the role of genes in schizophrenia is genetic counselling. Potential parents with a history of schizophrenia or relatives with schizophrenia can receive advice for family planning.
• Alternative explanations such as those suggested by Frith (1992), claim that schizophrenia is not biological in nature but is the result of specific difficulties in cognitive processing.
• Alternative cognitive explanations are also supported by Baron-Cohen (1985) who suggests that schizophrenia is explained by having an impaired ‘Theory of Mind’, which is the ability to see something from someone else’s perspective.
• An alternative biological explanation is the dopamine hypothesis which suggests that an overactivity of dopamine in certain brain regions may contribute to the development of schizophrenia.