biological explanations of schizophrenia

Question 1

support for the genetic explanation

Answer 1

ripke, gottesman

Question 2

what does ripke support

Answer 2

genetic explanation

Question 3

what does gottesman support

Answer 3

genetic explanation

Question 4

describe ripke

Answer 4

combined results from genome-wide studies into SZ and found 108 genetic variations that may increase the risk of SZ.

Question 5

describe gottesman

Answer 5

conducted a large-scale family study, finding that the closer the family members were in DNA to a person with SZ, the more likely it was for them to have SZ. for example, in identical twins, concordance rates were 44%, while it is 1% in the general population.

Question 6

contradictory evidence for genetic explanation

Answer 6

brown et al.

Question 7

what does brown et al. contradict

Answer 7

genetic explanation

Question 8

describe brown et al.

Answer 8

found that SZ can appear in people with no family history of the disorder. instead, positive correlations have been found between SZ and mutated parental cells, such as sperm cells that have been mutated by radiation, toxins, etc. this may increase the risk of SZ by 0.7% with fathers under 25, and by 2% with fathers over 50.

Question 9

support for dopamine hypothesis

Answer 9

curran et al.

Question 10

what does curran et al. support

Answer 10

dopamine hypothesis

Question 11

describe curran et al.

Answer 11

found that drugs that increase dopamine levels make the symptoms of SZ more extreme.

Question 12

contradictory evidence for dopamine hypothesis

Answer 12

ripke

Question 13

what does ripke contradict

Answer 13

dopamine hypothesis

Question 14

describe ripke (as contradictory evidence)

Answer 14

many of the candidate genes identified by ripke code for production of neurotransmitters, but not just dopamine. for example, some effect glutamate production, so the dopamine hypothesis may be limited.

Question 15

support for neural correlates

Answer 15

juckel et al., allen et al.

Question 16

what does juckel et al. support

Answer 16

neural correlates for negative symptoms

Question 17

what does allen et al. support

Answer 17

neural correlates for positive symptoms

Question 18

describe juckel et al.

Answer 18

found lower levels of activity in the ventral striatum in those with SZ when compared to a control group. also found a negative correlation between levels of activity and severity of negative symptoms of SZ, particularly avolition, as the ventral striatum is linked to motivation.

Question 19

describe allen et al.

Answer 19

found lower levels of activity in the superior temporal gyrus and anterior cingulate gyrus in those who were experiencing auditory hallucinations when compared to a control group while identifying pre-recorded speech as theirs, or someone else’s.