Lesson 4: Genetic + Neural Explanations

Question 1

What do genetic explanations suggest? What was the study?

Answer 1

• Would-be offenders inherit a gene that predisposes them to commit crime
• Large (1930) investigated 13 Mz and 17Dz twins. At least one of the twins in each pair served time. 10/13 Mz twins had both spent time, but only 2/17 had both spent time.

Question 2

What is another genetic explanation? Name a study that agrees with this?

Answer 2

• Criminal behaviour is polygenic, these genes are known as candidate genes (responsible for causing criminal behaviour)
• Psychologist conducted a genetic analysis of 900 Finnish offenders and found 2 genes: MAOA controlling dopamine and serotonin linked to aggression, and CDH13 leading to substance abuse and ADD. This high risk combustion were 13x likely to have a history of violent behaviour

Question 3

What is a Neural explanations ?

Answer 3

• Neural differences in the brains of criminals compared to non criminals
• Anti-social personality disorder is associated with reduced emotional responses + a lack of empathy = common characteristic in convicted criminals
• People with APD have reduced activity in the pre-frontal cortex (regulates emotion). Psychologist found 11% reduction in grey matter
• Criminals with APD can Experian empathy but do more sporadically. When asked to empathise, criminals’ empathy reactions activated (by mirror neurons), suggesting that ADP individuals are not totally without empathy but have a neural switch that needs to be turned on

Question 4

Evaluation (-)

Answer 4

• Concordance rates in MZ are not high so non-genetic environmental factors can play a part. Concordance rates could be from shared learning experiences
• Brain scanning studies show pathology in brains of criminal psychopaths but cannot conclude if the abnormalities are genetic or signs of early abuse
• Offending behaviour is too vague as some crimes can be more biological e,g fraud vs physical aggression
• Biologically reductionist: criminals are complex and this explanation is oversimplified. Genetics are not the only factor
• Biological determinism: legal system issue. The offender is not personally/morally responsible so it is unethical to punish someone without free will