Biological Explanations for SZ (Family/Twin/Adoption/Dopamine Hypothesis)

Question 1

1. Genetic Explanations of Schizophrenia

Answer 1

Evidence of a genetic link, comes from family studies
which indicate that the closer the genetic relationship to someone with schizophrenia,the greater the chance of developing the disorder.

Question 2

what did gottesmann study

Answer 2

Gottesman (1991) Studied concordance rates in children with SZ parent(s) or siblings
2x SZ parents - 46% concordance

1x SZ parent - 13% concordance

1x SZ sibling - 9% concordance

Question 3

Twins- mz concordance compared to dz concordance

Answer 3

MZ concordance - 40.4%

DZ concordance - 7.4%

Question 4

Adoption

Tienari et al. Compared siblings raised together vs apart.

Answer 4

164 adoptees had SZ mothers. Of these, 6.7% also developed SZ.

197 adoptees were in the control group. 2% of them developed SZ.- genetic liability for SZ is “decisively confirmed”

Question 5

Dopamine Hypothesis

Answer 5

The dopamine hypothesis suggests that
schizophrenia is caused by a high level of
sensitivity in dopamine receptors. This causes the messages from neurons that transmit dopamine to fire too easily or too often.

According to Snyder (1976) if too
much dopamine is released into the synapse it can lead to the onset of schizophrenia.

Question 6

Hyperdopaminergia

in the subcortex

Answer 6

an excess of dopamine receptors in
Broca’s area might be associated with poverty of speech
and/or the experience of auditory hallucinations

Question 7

Hypodopaminergia

in the cortex

Answer 7

this could
explain negative symptoms as high levels in the mesocortical dopamine system are associated
with negative symptoms

Question 8

A strength of the research into the dopamine hypothesis

Answer 8

it has practical applications
as it has led to the development of an effective treatment. From the research using schizophrenics, new drugs have been developed such as Clozapine,
which is much more effective than neuroleptics at relieving schizophrenic behaviour. This suggests that psychiatrists can understand the role played by
neurotransmitters when treating different types of schizophrenia and thus improve
the patient’s quality of life.