2. Schizophrenia Biological Explanations

What is the relationship between genetics and schizophrenia?

• Schizophrenia is caused by environmental factors only

• People inherit schizophrenia directly from their parents

• There is no genetic component to schizophrenia

• People inherit a genetic predisposition to schizophrenia

What is the concordance rate for schizophrenia among MZ twins according to Gottesman (1991)?

• 0%

• 9%

• 17%

• 48%

What is the main limitation of twin studies in understanding the genetic component of schizophrenia?

• They only involve MZ twins

• They do not provide any evidence for genetic influence

• They cannot separate the impact of nature and nurture

• They are not reliable in determining genetic predisposition

What did Tienari et al. (2000) find in their adoption study in Finland?

• Children of schizophrenia sufferers are at heightened risk even when adopted into families without schizophrenia

• Children of schizophrenia sufferers are not at heightened risk if adopted to families with no schizophrenia

• Selective placement of adoptees is a limitation of the findings

• The control had no incidence of schizophrenia

What is the main limitation of the genetic argument in understanding schizophrenia?

• Genetic vulnerability is not a factor in schizophrenia

• Genetics have no role in the development of schizophrenia

• There is no strong evidence to support genetic influence

• It is difficult to separate the impact of nature and nurture

What is the main strength of the genetic argument in understanding schizophrenia?

• There is no strong evidence to support genetic influence

• There is overwhelming evidence to support genetic influence

• Genetic vulnerability is not a factor in schizophrenia

• Genetics have no role in the development of schizophrenia

What is the original dopamine hypothesis of schizophrenia?

• Schizophrenia is caused by high levels of dopamine in the cortex

• Dopamine has no role in schizophrenia

• Schizophrenia is caused by excessive activity of dopamine in the subcortex

• Schizophrenia is caused by low levels of dopamine in the subcortex

What is the role of the subcortex in the original dopamine hypothesis?

• It includes the auditory cortex

• It is responsible for thinking and decision making

• It is associated with positive symptoms of schizophrenia

• It is not involved in schizophrenia

What is the more recent version of the dopamine hypothesis focused on?

• Hypodopaminergia in the subcortex

• Hyperdopaminergia in the cortex

• Hypodopaminergia in the cortex

• Hyperdopaminergia in the subcortex

What is a limitation of the dopamine hypothesis explanation of schizophrenia?

• The hypothesis is too complex to understand

• There is no evidence to support the hypothesis

• There is mixed evidence for the hypothesis

• The hypothesis is not relevant to schizophrenia