Biological Explanations of Schizophrenia

Question 1

what does the biological explanation say about genetic factors in reference to schizophrenia

Answer 1

the risk of the developing the disorder among individuals who have family with schizophrenia is higher than for those who do not

Question 2

what are the three types of studies that support the genetic factors in schizophrenia

Answer 2

• family studies
• twin studies
• adoption studies

Question 3

what have family studies shown about schizophrenia

Answer 3

the closer the degree of relatedness, the greater the risk of developing schizophrenia

Question 4

who provides a family study for genetic factors of schizophrenia

Answer 4

Gottesman

Question 5

what did Gottesman find in his study on family as a genetic factor for schizophrenia

Answer 5

of a group of parents who both had SZ, 46% had one child with SZ

Question 6

what do twin studies show about the genetic factors of schizophrenia

Answer 6

monozygotic twins have a concordance rate of 40.4% for SZ whereas dizygotic twins have a rate of 7.4%

Question 7

what is a monozygotic twin

Answer 7

twins who are gentically identical

Question 8

who is a dizygotic twin

Answer 8

twins who are not genetically identical

Question 9

who carried out the twin studies

Answer 9

Joseph

Question 10

why are adoption studies important as part of the biological explanations of schizophrenia

Answer 10

they use genetically related individuals who have been reared seprately - showing the impact of genetics and environment

Question 11

who provided an adoption study

Answer 11

Tienari

Question 12

what did Tienari find in his study that can be used to support the biological explanations of schizophrenia

Answer 12

11/14 of the children who developed schizophrenia had a genetic predisposition to the disease despite being adopted into a different family

Question 13

what are the two aspects of neural correlates for the biological explanation of schizophrenia

Answer 13

• the dopamine hypothesis
• specific brain areas

Question 14

what are the two parts to the biological explanations of schizophrenia

Answer 14

• genetic factors
• neural correlates

Question 15

generally, what does the dopamine hypothesis suggest about schizophrenia

Answer 15

there is a relationship between dopamine levels and the development of schizophrenia

Question 16

what biological differences are people with schizophrenia thought to have

Answer 16

an abnormally high number of D2 receptors on receiving neurons

Question 17

what is the impact of a high number of D2 receptors

Answer 17

more dopamine binds to the receptors therefore more neurons are fired

Question 18

what was the original dopamine hypothesis

Answer 18

too much release of dopamine can lead to the onset of schizophrenia as people with schizophrenia are thought to have an abnormally high number of D2 receptors

Question 19

what is the updated dopamine hypothesis

Answer 19

• high levels of dopamine in the mesolimbic dopamine system are associated with positive symptoms
• low levels of dopamine in the mesocortical dopamine system are associated with negative symptoms

Question 20

what evidence is there for the dopamine hypothesis

Answer 20

-drugs that increase dopaminergic activity
- drugs that decrease dopaminergic activity

Question 21

what drugs increase dopaminergic activity

Answer 21

amphetamine = dopamine agonist

Question 22

what effect does amphetamine have and how does this support the dopamine hypthesis

Answer 22

stimulates cells containing dopamine causing the synapse to be flooded with it, leading to the development of characteristic symptoms of schizophrenia (hallucinations and delusions)

Question 23

what drugs decrease dopaminergic activity

Answer 23

antipsychotic drugs

Question 24

what effect do antipsychotic drugs have and how does this support the dopamine hypothesis

Answer 24

block the activity of dopamine, reducing neural pathways which eliminates symptoms like hallucinations and delusions

Question 25

what are the four brain area involved with schizophrenia

Answer 25

- prefrontal cortex - hippocampus - grey matter - white matter

Question 26

how are the brain areas involved with schizophrenia studied

Answer 26

- post mortems - fMRI

Question 27

what is the prefrontal cortex important for in the brain

Answer 27

involved in executive control (planning, reasoning, judgement)

Question 28

what is the relationship between the prefrontal cortex and schizophrenia

Answer 28

this area is impaired in schizophrenia patients

Question 29

what is the relationship between the prefrontal cortex and schizophrenia symptoms

Answer 29

issues with the PFC can explain the cognitive symptoms of schizophrenia because they stem from damage to the PFC

Question 30

what is the effect of an impaired hippocampus

Answer 30

deficits in nerve connections correlates with the degree of working memory impairments

Question 31

how is the hippocampus linked to schizophrenia

Answer 31

issues in the hippocampus result in memory problems - a key symptom of schizophrenia

Question 32

what is grey matter

Answer 32

cell bodies and unmyelinated axons

Question 33

what is the relationship between people with schizophrenia and grey matter

Answer 33

people with schizophrenia have a reduced volume of grey matter and enlarged ventricles

Question 34

what is white matter

Answer 34

nerve fibres covered in myelin which helps to conduct information quickly

Question 35

what is the relationship between schizophrenia and white matter

Answer 35

schizophrenia patients have reduced white matter pathways than compared to healthy controls