Biological explanations for schizophrenia

• What is the inheritance pattern of schizophrenia (SZ)?

  SZ is inherited through generations through the transmission of genes.
• What does the term "polygenic" refer to in the context of SZ?


  It refers to the involvement of hundreds of genes in the inheritance of SZ.
• What is the candidate gene PCM1 associated with?


  PCM1 codes for a protein involved in cell division.
• What is the significance of the DRD3 gene in schizophrenia?


  DRD3 is a dopamine receptor gene linked to dopaminergic pathways.
• What did Gottesman (1991) find regarding concordance rates in twin studies?


  Concordance rates were 17% for dizygotic (DZ) twins and 48% for monozygotic (MZ) twins.
• What do the concordance rates in twin studies suggest about the causes of SZ?

  They suggest that genetics are an important cause of SZ but not the only cause.
• What are some problems associated with twin studies in the context of SZ?

  Concordance rates are never 100%, and MZ twins share environments, complicating genetic attribution.
• What was the sample size of MZ twins expected to have schizophrenia?

  Only 1% of MZ twins would be expected to have schizophrenia.
• What did the Finnish Adoption Study by Tienari (1991) reveal about genetics and SZ?


  It showed that 10% of children with a biological mother who had SZ developed SZ, compared to 1% in the matched group without family history.
• What do the findings from Tienari's study suggest about the role of genetics in SZ?

  They suggest that genetics are an important but not complete explanation for the cause of SZ.
• What does the term "neural correlates" refer to in the context of SZ?


  It refers to correlations between brain structures/chemicals and symptoms of SZ.
• What is the dopamine hypothesis in relation to SZ?


  The dopamine hypothesis links SZ to excess activity of dopamine in subcortical areas of the brain.
• What is hyperdopaminergia?


  Hyperdopaminergia refers to excess activity of dopamine in the brain.
• What are some potential causes of hyperdopaminergia?

  Potential causes include elevated presynaptic dopamine, excess dopamine release, and increased receptor density on the postsynaptic neuron.
• What is hypodopaminergia?


  Hypodopaminergia refers to low activity of dopamine in the prefrontal cortex.
• How do dopamine neurons relate to symptoms of SZ?

  Dopamine neurons help guide attention, and disturbances may lead to problems with perception, attention, and thought.
• What does the use of antipsychotic drugs suggest about the role of dopamine in SZ?

  It suggests that dopamine overactivity is important in SZ, as these drugs reduce positive symptoms.
• What is the role of clozapine in treating SZ?

  Clozapine is an effective treatment that binds to dopamine and serotonin receptors.
• What are some environmental risk factors for SZ?

  Environmental risk factors include social adversity, pregnancy complications, prenatal stress, and psychoactive substance use.
• How does knowledge of biological explanations for SZ impact treatment?

  It leads to the development of treatments, such as antipsychotic medication, to reduce symptoms.
• What is a criticism of reductionist explanations of SZ?

  Reductionism oversimplifies a complex disorder, suggesting a holistic approach might be better.
• What does determinism imply in the context of biological explanations for SZ?


  Determinism suggests that SZ is destined due to genetic predisposition, limiting personal choice.
• How can understanding genetic predispositions help in the context of SZ?

  It allows for early identification and intervention for individuals at risk of developing SZ.