genetic and neural explanations

Question 1

How do twin studies illustrate the importance of genes?

Answer 1

Lange - 13 MZ 17 DZ twins where one twin served time in jail
10 MZ but 2 DZ had co twin in prison
Genes must be important

Question 2

Describe adoption studies into genetic explanations

Answer 2

Crowe - adopted children with bio criminal parent had 50% risk of criminal record by 18
Adoptees without criminal parent had 5% risk

Question 3

Describe Tiihonen’s research

Answer 3

Genetic analysis of 900 offenders
Abnormalities in 2 genes - MAOA and CDH13
Pps with this combo were 13x more likely to have history of violent behaviour
Not replicated

Question 4

What is the MAOA gene?

Answer 4

Controls dopamine and serotonin

Linked to aggressive behaviour

Question 5

What is CDH13?

Answer 5

Linked to substance abuse and ADHD

Question 6

What is the diathesis stress model?

Answer 6

Genetics moderated by environment

Trigger such as dysfunctional environment or criminal role models

Question 7

What is antisocial personality disorder?

Answer 7

Much neural research focuses on people with APD

Reduced emotional responses, lack of empathy, characterises convicted criminals

Question 8

Describe Raine’s research

Answer 8

Brain images found APD patients have reduced activity in prefrontal cortex - regulates emotions
11% reduction in grey matter in prefrontal context of APD people

Question 9

Describe Keysers’ research

Answer 9

Only when criminals were asked to empathise did their reaction activate (controlled by mirror neurons)
Suggests they have a neural switch that can be turned on and off unlike normal brain

Question 10

Evaluation - problems with twin studies

Answer 10

Judgements of zygosity based on appearance

Twins tested in same environment - concordance rates due to shared experience

Question 11

Evaluation - support for diathesis stress model

Answer 11

Mednick - 13000 Danish adoptees studied
When neither bio or adoptive parents had convictions, % of adoptees was 13.5%
Either bio - 20%
Adoptive and bio - 24.5%

Question 12

Evaluation - problems with adoption studies

Answer 12

Many children experience late adoption - infancy spent with bio parents, or they maintain contact
Mednick’s study only looked at petty offences

Question 13

Evaluation - biological reductionism

Answer 13

Criminality is complex
Crime runs in families but so does emotional instability, mental illness, poverty
Hard to separate genes from other factors
No 100% concordance with MZ twins

Question 14

Evaluation - biological determinism

Answer 14

Criminal gene does not fit with justice system

Must be held responsible