Genetic and Neural Explanations

Question 1

who did Twin studies?

Answer 1

Lange (30)

Question 2

what were the twin studies?

Answer 2

• lange (30) 13 MZ and 17 DZ
• one of each pair had been to prison
• 10 MZ na d2 DZ where both twins were criminals

Question 3

– poor control of twin studies

Answer 3

• done long ago so control bad - zygosity was judge on appearance rather than DNA
• small samples
• confounding variables like shared environment

Question 4

who did adoption study?

Answer 4

Crowe (72)

Question 5

what was the adoption study?

Answer 5

• adopted kids with biological criminal parents 50% more likely to have criminal record by 18
  (adoptees with normal parents only had 5% risk)

Question 6

– confound variable of adoption study

Answer 6

• many of the kids spent infancy with biological parent and stayed in contact with them after adoption

Question 7

– criminal figures in adoption study are unrepresentative

Answer 7

• Medick said criminal figures were of petty crimes like robbery
• means its unrepresentative of more serious crimes like assault

Question 8

who did candidate genes?

Answer 8

Tiihonen (14)

Question 9

what was the study into candidate genes?

Answer 9

• analysed 900 offenders
• found they had efficiency in genes MAOA (dopamine and serotonin) and CDH13 (drug use and ADHD)
• gave 13x greater risk of offending

Question 10

– negative evaluation of candidate genes study

Answer 10

research in its infancy so hasn’t been replicated

Question 11

what is is the diathesis stress model of offending?

Answer 11

• offending is caused by a combination of biological and physiological dysfunctions (like genes and bad environment)

Question 12

+ what is the study that supports the diathesis stress model?

Answer 12

• Mednick (84) studied 13,000 danish adoptees
• 13.5% criminality if Noether biological or adoptee parent was criminal
• 20% if biological parent was criminal
• 24.5% if both parents were criminal

Question 13

how did they study neural differences of criminals?

Answer 13

studied neural difference in APD (anti social personality disorder) people - reduced emotion and empathy

Question 14

what did studying the prefrontal cortex of APD people show?

Answer 14

• Raine (00) found APD people have less activity

- also found 11% reduction in grey matter of PFC of APD people compared to control group

Question 15

what did studies into mirror neutrons find about criminals?

Answer 15

• Keysers et al (11) found criminals can switch empathy on and off
• like when watching a sad video and they were asked to feel empathy for the person and pain
  (for normal people empathy is always on)