Forensic Psychology: biological explanations

Question 1

Genetic explanations AO1 points

Answer 1

1. twin + adoption studies suggest genes predispose offendeers to crime
2. candidate genes
3. diathesis stress model

Question 2

genetic explanations: twin + adoption studies suggest genes predispose offendeers to crime (4)

Answer 2

A . Christiansen:
- studied over 3500 twin pairs in denmark
- found a concordance rate for offender behavior of 35% for MZ males and 13% for DZ males

B. Crowe
- found that adopted children who has a biological mother with a criminal record had a 50% risk of having a criminal record age 18 .
- whereas adopted children whos mother didnt have a criminal record only had a 5% chance

Question 3

genetic explanations: candidate genes (3)

Answer 3

1. MAOA gene - regulates serotonin + linked to aggressive behavior
2. CDH13 gene - linked to substance abuse + ADHD

genetic analysis study of 800 offenders found that 5 -10% of all severe violent crimes in finland is attributed to MAOA and CDH13 gene

Question 4

genetic explanations: diathesis-stress model (2)

Answer 4

tendancy to offending behavior due to combination of:
1. genetic predisposition (diathesis)
2. biological or psychological stressor

Question 5

Neural explanations AO1 points (3)

Answer 5

1. antisocial personality disorder
2. less activity in prefrontal cortex = less emotional regulation
3. mirror neurons

Question 6

Neural explanations: antisocial personality disorder

Answer 6

• there are neural differences in brains of offenders + non offenders
• many offenders have diagnosis of APD
• eg APD associated w lack of empathy and reduced emotional responses

Question 7

neural explanations AO1: prefrontal cortex (2)

Answer 7

• Raine found reduced activity and 11% reduction in volume of grey matter in prefrontal cortex of ppl w APD compared to controls
• pre frontal cortex regulates emotional behavior

Question 8

neural explanations AO1: mirror neurons (3)

Answer 8

Keysers found that only when offenders were asked to empathise did they show an empathy reaction (controlled by mirror neurons in brain)

suggests that APD individuals to experience empathy but may have a neural switch that turns on and off

in a normally functioning brain the empathy switch is permanently on