biological explanation: genetic and neural

Question 1

AO1: genetic explanation- twin studies

Answer 1

compares MZ (identical) twins and DZ (non-identical) twins, one of the twins in each pair has spent time in prison. Found 10 of the MZ twins had both spent time in prison, compared to only 2 of the DZ twins

Question 2

AO1: genetic explanation- adoption studies

Answer 2

found that adopted children whose biological mothers had a criminal record were highly more likely to have a criminal record by the age of 18, than those with biological mother who didn’t have a criminal record

Question 3

AO1: genetic explanation- candidate genes

Answer 3

2 genes are suggested to be associated its violent crimes.
- The MAOA gene controls dopamine
and serration in the brain
- the CDH13 genes which is linked to substance abuse and ADHD

samples 800 offenders, found offenders with this combination of genes were 13 times more likely to have a history of violent behaviour

Question 4

AO3: genetic explanation: limitation- assumes twins have equal environments

Answer 4

P: uses twin studies and assumes there is equal environments for the twins
E: shared environment may apply more to MZ twins as they look identical, so may be treated the same
E: high concordance rates for MZ twins in the studies may just be because they are treated more similarly than DZ twins

Question 5

AO3: genetic explanation: strength- supports diathesis stress model of offending

Answer 5

P: supports diathesis stress model of offending
E: study on large sample of Danish adoptees, neither biological or adoptive parents had convictions.
E: low amount of adoptees had convictions, rose when biological parents had conviction, and rose even further when both adoptive and biological parents had convictions
L: shows both genetic inheritance and environment play an important role in offending
HOWEVER, many adoptions take place when children are older, meaning they spent several years with their biological parents. Suggesting it could be all environmental influence, this should be considered when looking at the findings

Question 6

AO1: neural explanation- prefrontal cortex

Answer 6

individuals who experience antisocial personality disorder show reduced activity in the prefrontal cortex, which is responsible for regulating behaviour.

Found a reduction in the volume of grey matter (where processing is done) in the PFC of people with APD compared to control group

Question 7

AO1: neural explanation- mirror neurons

Answer 7

a type of brain cell that fires when you do an actions, and also when you watch someone else doing the same action

offenders with APD were asked to empathise (being shows a person on film experience pain). They did empathise.

mirror neurons were activated. Suggests that people with APD may have a ‘switch’ that can be turned off and on.

Question 8

AO3: neural explanation: strength- supports for link between crime and frontal lobe

Answer 8

P: supports for link between crime and frontal lobe
E: researchers reviewed evidence of frontal lobe damage and antisocial behaviour
E: found they tended to show impulsive behaviour, emotional instability and inability to learn from their mistakes.
L: supports the idea that brain damage may be a causal factor of offending behaviour

Question 9

AO3: neural explanation: limitation- biologically determinist

Answer 9

P: biologically determinist
E: doesn’t consider other factors such as psychological explanations
E: this could include offenders environment and family
L: needs to be considered when looking at this explanation