biological explanations for schizophrenia

Question 1

what does the genetic explanation suggest

Answer 1

that its an inherited disorder where faulty genes are passed on from generation to generation

Question 2

who studied twin studies

Answer 2

gottesman

Question 3

what did gottesman find (twin)

Answer 3

summarised 40 twin studies and found a concordance rate of 48% for MZ twins and 17% for DZ twins

Question 4

what do gottesmans results show

Answer 4

that as MZ twins are more concordant than DZ twins this suggests a greater similarity due to genetics

Question 5

mz twins

Answer 5

share 100% of the same DNA

Question 6

dz twins

Answer 6

share 50% of the same DNA

Question 7

who studied family studies

Answer 7

gottesman

Question 8

what did gottesman investigate

Answer 8

concordance rates of schizophrenia in a child if both, one or none of the parents had it

Question 9

what did gottesman find with both parents

Answer 9

if both parents had schizophrenia there was a 46% chance of developing the disorder

Question 10

what did gottesman find with one parent

Answer 10

if one parent had the disorder there was a 16% chance of developing the disorder

Question 11

what did gottesman find with no parents

Answer 11

there was a 1% chance of developing the disorder

Question 12

what did gottesman family studies show

Answer 12

a higher concordance rate with children with 2 schizophrenic parents than with just 1, suggests the concordance rate is due to genetics

Question 13

who studied adoption studies

Answer 13

tiernari

Question 14

what did tiernari study

Answer 14

112 adopted children who had been separated from their schizophrenic mothers compared to 135 adopted children who did not have schizophrenic mothers

Question 15

what did tiernari find

Answer 15

10.3% of those with schizophrenic mothers developed the disorder compared to 1.1% without

Question 16

what do tiernaris results show

Answer 16

that schizophrenic genes still impacted the childrens behaviour despite being in a different environment
suggesting there is a genetic element to schizophrenia

Question 17

what are candidate genes

Answer 17

genes associated with risk of inheritance

Question 18

what is schizophrenia in terms of genetics

Answer 18

polygenic and aetiologically heterozygous

Question 19

what does polygenic mean

Answer 19

it requires a number of factors to work in combination not just one specific gene

Question 20

what does aetiologically heterogenous mean

Answer 20

studies have identified a number of different candidate genes that lead to schizophrenia

Question 21

what did ripke study

Answer 21

genetic makeup of schizophrenic patients

Question 22

what did ripke compare

Answer 22

the genome of 37000 schizophrenic patients compared to 113000 controls

Question 23

what did ripke find

Answer 23

108 separate genetic variations were associated with increased risk of schizophrenia
including coding for the functioning for a number of neurotransmitters including dopamine

Question 24

what do ripkes findings suggest

Answer 24

there is no one single gene that causes schizophrenia, there are multiple genes that may have an influence
- which could explain why there are so many types of schizophrenia

Question 25

what is the dopamine hypothesis

Answer 25

the brains chemical messengers appear to work differently in the brain of a patient with schizophrenia in particular dopamine

Question 26

what are the two parts of the dopamine hypothesis

Answer 26

hyperdopaminergia and hypodopaminergia

Question 27

where does hyperdopaminergia occur

Answer 27

in the subcortex

Question 28

what is hyperdopaminergia

Answer 28

high levels or activity of dopamine in the subcortex

Question 29

what an example of hyperdopaminergia

Answer 29

high levels of dopamine in brocas area may be associated with poverty of speech and auditory hallucinations

Question 30

what type of symptoms is hyperdopaminergia associated with

Answer 30

positive symptoms

Question 31

where does hypodopaminergia occur

Answer 31

the prefrontal cortex

Question 32

what is hypodopaminergia

Answer 32

low levels of dopamine in the prefrontal cortex

Question 33

what is the prefrontal cortex responsible for

Answer 33

decision making

Question 34

what symptoms are associated with hypodopaminergia

Answer 34

negative symptoms

Question 35

what are neural correlates

Answer 35

measurements of the structure or function of the brain that correlate with an experience

Question 36

neural correlates of negative symptoms

Answer 36

avolition involves the loss of motivation motivation involves the anticipation of a reward and certain regions of the brain

Question 37

what part of the brain correlates with avolition

Answer 37

ventral striatum

Question 38

what study shows this

Answer 38

juckel

Question 39

what did juckel find

Answer 39

a negative correlation between activity levels in the ventral striatum and the severity of overall negative symptoms

Question 40

who studied neural correlates of positive symptoms

Answer 40

allen

Question 41

what did allen find

Answer 41

reduced activity in the superior temporal gyrus and anterior cingulate gyrus in the brains of schizophrenic patients compared to control

Question 42

what positive symptom is decreased activity of the brain in these areas a neural correlate with

Answer 42

auditory hallucination

Question 43

a strength of the biological explanation is that it has practical applications

Answer 43

- effective treatment of schizophrenia found in antipsychotics which were developed as a result of the biological explanation - antipsychotics reduce dopamine levels in the brain - as an effective treatment has been developed as a result of the explanation, the explanation must hold some validity and explanatory power for the development of schizophrenia

Question 44

one limitation of the biological explanation of schizophrenia is that it cannot establish cause and effect

Answer 44

- we cannot be sure if fluctuating dopamine levels are causing schizophrenia or if schizophrenia is caused fluctuating dopamine levels - this is a limitation as cause and effect cannot be established between the variables, we cant be sure which variable causes schizophrenic symptoms or if another variable is impacting it. - which limits the explanatory power of the biological explanation as an explanation for schizophrenia and limits the validity of the explanation

Question 45

the biological explanation is reductionist

Answer 45

a limitation of the biological explanation is that its biologically reductionist and an oversimplistic explanation of schizophrenia - carlson argued that the biological explanation is overly simplistic as other neurotransmitters may affect schizophrenia development such as glutamate and serotonin as common atypical antipsychotics that reduce symptoms also reduce the presence of these neurotransmitters in the brain - this is a limitation of the biological explanation only considers the impact of dopamine levels on the development of schizophrenia without considering other factors. - as a result the biological explanation fails to provide a holistic explanation to schizophrenia development limiting the explanations explanatory power and validity

Question 46

a strength of the biological explanation is that it has a lot of research support

Answer 46

supporting evidence of the biological explanation includes gottesmans twin studies investigating concordance rates of schizophrenia between MZ twins (share 100% of their dna) which was 48% and DZ twins (share 50% of their dna) which was 17% suggesting that there are genetic factors in the development of schizophrenia as the biological explanation suggests as concordance was higher in MZ twins than DZ twins - this suggests that the biological explanation holds at least some validity in explaining the development of schizophrenia