biological explanations of SZ

Question 1

strengths of genetic explanations
studies

Answer 1

Gottesman- family study- the relationship from large scale family study shows that someone with a aunt with schizophrenia has a 2% chance of developing it increasing to 9% in a sibling and 48% in a monozygotic twin.

Ripke et al.- combined all previous data from genome wide studies. The genetic makeup of 37,000 with schizophrenia was compared to 113,000 without and 108 separate genetic variations were associated with increased risk.

Brown et al- gene mutation. there are positive correlations between paternal age and risk of schizophrenia, incresing from around 0.7% with fathers under 25 to over 2% in fathers over 50. Supporting the fact that genes play a part in incresed risk as theres more gene mutation as we age.

Question 2

strengths of genetic explanations
genetic counselling

Answer 2

genetic explanations have lead to genetic counselling which allows people to understand how conditions may effect you or your family. It can help people see the likelihood of inheriting the disorder of their children having it. they can also be informed on the treatments available and get access to resources and a research opportunity. Showing how understanding the part genetics play leads to better understanding and education for those who may be at risk.

Question 3

weakness of the genetic explanation
other factors to consider

Answer 3

Di Forti et al.- increased risk of developing schizophrenia is associated with smoking cannabis in teenage years.

Mokved et al- study found 67% of their schizo patients and psychotic conditions reported atleast one childhood trauma compared to 38% in a control group.

Question 4

strengths of dopamine hypothesis
supporting studies

Answer 4

Curran et al- found that amphetamines increase DA, worsening symptoms in those with schizophrenia and inducing them in those without.

Tauscher et al- antipsychotics= rapid disengagement of DA receptors. Tauscher et al found this reduced DA activity and symptoms of SZ. Theres also evidence that it induces symptoms of parkinsons.

Question 5

weakness of dopamine hypothesis
other things to consider

Answer 5

Mccutcheon et al.- live scanning and post-mortem studies have consistently found differing levels of glutamate (learning attention and memory) in the brains of schizophrenic patients showing that dopamine is not the only chemical implicated.

Question 6

strength of brain abnormalities
supporting studies

Answer 6

Juckel et al- avolition is negatively correlated with activity in the ventral striatum according to Juckel et al who found lower levels of activity in schizophrenics compared to controls.

Allen et al. scanned patients with auditory hallucinations compared to a control and found lower activation levels in superior temporal gyrus and anterior cingulate gyrus of hallucination group. b