Biological explanation of schizophrenia

Question 1

what are the 3 parts to the biological exp?

Answer 1

• genetics
• neural correlates
• dopamine hypothesis

Question 2

define the genetic theory
(AO1)

Answer 2

• says sz is inherited and passed on from one gen to the next thru genes
• therefore a person is born with a genetic predisposition to sz
• several maladaptive ‘candidate’ genes such as PCM1 are involved , which are polygenic (inc. vulnerability)
• studies have shown 108 genetic variations are associated in risk of developing sz

Question 3

define the research into the genetic theory
(AO1)

Answer 3

• 40 twins were studied
• it was found that the concordance rate for monozygotic twins (identical) was higher (48%) and for dizygotic twins it was lower (17%)
• therefore the closer the genetic link to somebody with sz, the higher the chance of developing sz

Question 4

Summarize the AO3 PEEL for the genetic theory

Answer 4

RTS about adopted children and schizophrenic parents

Question 5

What does neural correlates mean in terms of sz?

Answer 5

• Abnm within specific brain areas could be associated with the development of sz.
• Sz brains and normal brains are compared using brain scanning techniques such as FMRI scans to identify brain areas that may be linked to sz

Question 6

Define neural correlates
(AO1)

Answer 6

One neural correlate of sz is enlarged ventricles, this is associated with damage to central brain areas and pre frontal cortex which is associated with negative symptoms of sz

Question 7

what is the research into enlarged ventricles and neural correlates?
(AO1)

Answer 7

meta - analysis found that over half of indv tested with sz had increased ventricle size compared to a control group

Question 8

summarize the AO3 PEEL for neural correlates

Answer 8

RTS - brain scans on schizophrenic twins with enlarged ventricles

Question 9

What does dopamine hypothesis mean in terms of sz?
(AO1)

Answer 9

• the brains nts work diff in sz brain, esp dopamine as its believed indv with sz may release too much dopamine
  -or have many D2 receptors on the post synaptic neuron

Question 10

Define HYPERdopaminergia in the SUBcortex (2)
(AO1)

Answer 10

• high dopamine activity in central areas of the brain
• e.g brocas area may be associated with auditory hallucinations

Question 11

Define HYPOdopaminergia in the cortex (2)
(AO1)

Answer 11

• low dopamine activity in the prefrontal cortex
• associated with neg. symptoms of sz like avolition

Question 12

what is the STRETCH for hyper and hypodopaminergia?

Answer 12

• it has been suggested that cortical hypodopaminergia leads to subcortical hyperdopaminergia
• both high and low levels of dopamine in diff brain areas are involved in diff symptoms of sz

Question 13

what are the three AO3 PEELS for the biological exp?

Answer 13

• scientific methods
• biological determinism
• prac apps