Biological explanation

Question 1

What are genetics?

Answer 1

Inherited factors which make certain individuals more likely to develop a behaviour or mental disorder

Question 2

What genetic factor has schizophrenia been linked to?

Answer 2

Polygenetic sets of candidate genes

Question 3

What have family studies established?

Answer 3

That schizophrenia is more common among biological relatives of a person with schizophrenia

Question 4

With regards to family studies, what increases the risk of schizophrenia?

Answer 4

The degree of genetic relatedness

Question 5

What type of study did Gottesman conduct?

Answer 5

Family study

Question 6

What concordance rate did Gottesman find when both parents had schizophrenia?

Answer 6

46%

Question 7

What concordance rate did Gottesman find when one parent had schizophrenia?

Answer 7

13%

Question 8

What concordance rate did Gottesman find when one sibling had schizophrenia?

Answer 8

9%

Question 9

What do twin studies show?

Answer 9

A genetic link - but only when the concordance rate of MZ twins is higher than DZ twins

Question 10

What type of study did Joseph conduct?

Answer 10

A twin study

Question 11

What concordance rate did Joseph find for MZ twins?

Answer 11

40.4%

Question 12

What concordance rate did Joseph find for DZ twins?

Answer 12

7.4%

Question 13

What do adoption studies allow us to do?

Answer 13

Disentangle genes from environmental factors

Question 14

What type of study did Tienari conduct?

Answer 14

An adoption study

Question 15

How many Finnish adoptees took part in Tienari’s study?

Answer 15

164

Question 16

What percentage of the adoptees in Tienari’s study developed schizophrenia?

Answer 16

6.7%

Question 17

What percentage of the control group in Tienari’s study developed schizophrenia?

Answer 17

2%

Question 18

What does the dopamine hypothesis claim?

Answer 18

That an excess of dopamine in certain brain regions is associated with positive symptoms

Question 19

What are amphetamines?

Answer 19

Dopamine agonists

Question 20

What happens when ‘normal’ individiduals are exposed to amphetamines?

Answer 20

They start displaying schizophrenia-like positive symptoms

Question 21

What do antipsychotics do?

Answer 21

They block the activity of dopamine in the brain

Question 22

What effect do antipsychotics have on individuals with schizophrenia?

Answer 22

It reduces their positive symptoms

Question 23

What is hyperdopaminergia?

Answer 23

Too much dopamine

Question 24

What is hypodopaminergia?

Answer 24

Too little dopamine

Question 25

What can hyperdopaminergia in the subcortex cause?

Answer 25

Positive symptoms

Question 26

What can hypodopaminergia in the prefrontal cortex?

Answer 26

Negative symptom

Question 27

What hypothesis has been drawn about the cognitive symptoms of schizophrenia?

Answer 27

It’s the result of a deficit in the prefrontal cortex, and its connections with other brain regions like the hippocampus

Question 28

What happens to the hippocampus in schizophrenic patients?

Answer 28

It undergoes anatomical changes

Question 29

What happens to grey matter in schizophrenic patients?

Answer 29

The volume decreases

Question 30

Where does the volume of grey matter decrease in schizophrenic patients?

Answer 30

Frontal + temporal lobes

Question 31

What happens to white matter in schizophrenic patients?

Answer 31

They experience a decrease in the myelination of white matter pathways

Question 32

What are the 4 AO3 points for the biological explanation of schizophrenia?

Answer 32

1) MZ twins encounter more similar environments
2) Treatment support for dopamine hypothesis
3) Adoptees may be selectively placed
4) Challenges to the dopamine hypothesis

Question 33

What is the key assumption of twin studies?

Answer 33

MZ and DZ have an equal degree of shared environment

Question 34

Which type of twins experience more similar shared environment?

Answer 34

MZ

Question 35

What are MZ twins more likely to experience?

Answer 35

Identity confusion

Question 36

Where does evidence for the dopamine hypothesis come from?

Answer 36

Successful treatments which aim to reduce dopamine levels in the brain

Question 37

In the meta-analysis of studies into the use of antipsychotics, how many studies were included?

Answer 37

212

Question 38

In the meta-analysis of studies into the use of antipsychotics, what was found?

Answer 38

Antipsychotics are more effective than placebos at reducing schizophrenia symptoms

Question 39

What is a key assumption of adoption studies?

Answer 39

That adoptees are not selectively placed into families with particular backgrounds

Question 40

What belief was there about children of schizophrenic mothers?

Answer 40

There was a belief that any child of a mother admitted to a psychiatric hospital would be feeble-minded, insane and degenerate

Question 41

What did one study find about the adoptive placement of children of schizophrenic mothers?

Answer 41

It was highly unlikely they would be placed into families who had no history with schizophrenia

Question 42

Why have psychologists claimed that both the original and revised dopamine hypothesis have limited explanatory power?

Answer 42

Because antipsychotics do not alleviate hallucinations + delusions in around ⅓ of people who suffer from them