FP- Genetic and Neural Explanations

Question 1

What could criminal behaviour be?

Answer 1

Polygenic

Question 2

What does polygenic mean?

Answer 2

Polygenic is when no one single gene is responsible for offending

Question 3

What are candidate genes?

Answer 3

Many genes responsible for causing criminal behaviour.

Question 4

What study did Tilhonen et al conduct?

Answer 4

• Tilhonen et al conducted a genetic analysis of over 900 Finnish offenders

Question 5

What were the findings of the meta-analysis? (Tilhonen et al)

Answer 5

• It revealed abnormalities on two genes that may be associated with violent crime.
• MAOA gene: Controls dopamine and serotonin in brain and is linked to aggressive behaviour
• CDH13 gene: Linked to substance abuse and attention deficit disorder

Question 6

What does the MAOA gene control? And what is it linked to?

Answer 6

• It controls dopamine and serotonin in the brain

- It is linked to aggressive behaviour

Question 7

What is the CDH13 gene linked to?

Answer 7

• The CDH13 gene is linked to substance abuse and attention deficient disorder

Question 8

What does the diathesis-stress model suggest?

Answer 8

• It suggests that genetics influence criminal behaviour but it is moderated by the effects of the environment.

Question 9

What does the neural explanation suggest about criminal behaviour?

Answer 9

There may be neural differences in the brains of criminals compared with non-criminals.

Question 10

What is anti-social personality disorder associated with?

Answer 10

• APD is associated with reduced emotional responses and a lack of empathy, a condition that characterises many convicted criminals.

Question 11

In which cortex of the brain do individuals with anti-social personalities have reduced activity?

Answer 11

In the pre-frontal cortex.
- Raine et al found an 11% reduction in the volume of grey matter in the prefrontal cortex of people with APD compared to a control group.

Question 12

What neurons control empathy?

Answer 12

Mirror neurones.

Question 13

What did Keysers et al find about empathy in criminals with APD?

Answer 13

• Keysers et al. (2011) found that only when criminals were asked to empathise (with a person on a film experiencing pain)did their empathy reaction (controlled by mirror neuronsin the brain) activate.
• This suggests that APD individuals are not totally without empathy but may have a neural switch that needs to be turned on in order to experience it.
• In a normal brain the empathy switch is permanently switched on.

Question 14

Give evaluation for genetic and neural explanations

Answer 14

• Concordance rates in MZ twins are not high and leave plenty of room for non- genetic environmental factors. Concordance rates may be due to shared learning experiences rather than genetics.
• Brain scanning studies (such as Raine et al., 2000) show pathology in brains of criminal psychopaths, but cannot conclude whether these abnormalities are genetic or signs of early abuse.
• The term ‘offending behaviour’ is too vague. Some specific forms of crime may be more biological than others e.g. physical aggression.
• The genetic and neural explanation of criminal behaiour is an example of biological reductionism. Criminality is complex and explanations that reduce offending behaviour to a gene or imbalanced neurotransmitter may be inappropriate and overly simplistic. Criminal behaviour does seem to run in families, but so does emotional instability, mental illness, social deprivation and poverty. Twin studies never show 100% concordance rates in monozygotic twins, so genetics cannot be the only explanation for criminal behaviour.
• The genetic and neural explanation of criminal behaviour is also an example of biological determinism. This presents us with a dilemma for our legal system. If someone has a criminal gene they cannot have personal and moral responsibility for their crime. If this is the case it would be unethical to punish someone who does not have free will.