A01 biological explanations of schizophrenia

Question 1

Which explanation for schizophrenia recieved most support

Answer 1

Biological

Question 2

What are the 2 main sections

Answer 2

Genetic factors

The dopamine hypothesis

Question 3

What are the 3 sections in genetic factors

Answer 3

Family studies
Twin studies
Adoption studies

Question 4

Who tested family studies

Answer 4

Gottesman

Question 5

What did gottesman find

Answer 5

Children with 2 schizo parents have a concordance rate of 46%
Children with one schizo parent 13%
Sibling 9%

Question 6

Conclusion of family studies

Answer 6

Schizo is more common among biological relatives of a person with schizo and the closer the rel the greater the risk
Therefore biological relations could be an explanation

Question 7

Who tested twin studies

Answer 7

Joseph

Question 8

What did joseph do and find

Answer 8

Concordance rate of mono zygotic (fraternal) twins at 40%

7% for dizygotic (similar) twins

Question 9

What is the theory for the twin studies

Answer 9

If monozygotic twins are more concordant than dizygotic twins in terms of schizo then this suggests greater similarity is due to genetic factors

Question 10

Conclusion for twin studies

Answer 10

Findings support view that genetic factors could be used to explain cz of the higher concordance rate of schizo in monozygotic twins than dizygotic twins

Question 11

What is concordance rate

Answer 11

Similar to similarity rate

Question 12

What is monozygotic twins

And dizygotic twins

Answer 12

Identical twins who share 100% of their genes

Fraternal twins who share 50% of their genes

Question 13

Who tested adoption studies

Answer 13

Tienari et al

Question 14

What did tienari et al do and find

Answer 14

Tested genetic and environmental influences for schizo using genetically related indvs
6.7% of the adoptees with a schizo biological mum also recieved a diagnosis of schizo
3-2% of adoptees to a non schizo mum recieved a diagnosis of schizo

Question 15

Conclusion of adoption studies

Answer 15

Genetic liability to schizo confirmed despite genetically related indvs being reared apart (different environments)

Question 16

What are the 3 section of evidence for of the dopamine hypothesis

Answer 16

Amphetamines
Anti psychotic drugs
Parkinsons disease

Question 17

What is the dopamine hypothesis

4 points

Answer 17

Dopamine is a neurotransmitter
Messages from neurones that transmit dopamine fire too easily or too often leading to characteristics of schizo
Schizo have abnormally high numbers of D2 receptors on receiving neurones resulting in more dopamine building and therefore more neurones firing
Dopamine neurones play a role in guiding attention, so disturbances lead to problems with attention, perceptipn& thought

Question 18

Role of amphetamines

Answer 18

A dopamine agonist
Stimulates nerve cells containing dopamine
Causes the synapse to be flooded with the neurotransmitter

Question 19

What are amphetamines

Answer 19

A drug

Question 20

How do we know amphetamines support hypothesis

Answer 20

Large doses of the drug can cause the characteristic hallucinations and delusions of a schizo episode

Question 21

Role of Anti psychotic drugs

Answer 21

Dopamine antagonists
Block the activity of dopamine in the brain
Reduce stimulation of the dopamine system

Question 22

How do we know anti psychotics support hypothesis

Answer 22

They eliminate and alleviate symptoms of schizo eg hallucinations and delusions
Supported view that dopamine is a contributory factor in Dev of schizo

Question 23

How does Parkinsons disease support hypothesis

Answer 23

Low levels of dopamine are found I people with park is ons disease and when people took 5 he drug L-dopa to raise their dopamine levels they Dev symptoms of schizo