biological explanations to crime: genetic and neural

Question 1

what is the main assumption of a genetic explanation

Answer 1

suggests that would-be offenders inherit gene/genes that predispose them to commit crime

Question 2

what have twin studies shown about the biological basis to crime

Answer 2

more genetically similar an individual is to a criminal, the higher the concordance rate for committing a crime, therefore a genetic predisposition makes it more likely a person will turn to crime.

Question 3

outline a twin study that demonstrates the genetic basis to crime.

Answer 3

Christiansen studied over 3500 twins in Denmark and found concordance rates for offending behaviour of 35% for MZ and 13% for DZ.

Question 4

outline an adoption study that demonstrates the genetic basis to crime.

Answer 4

Crow found that adopted children whose biological mother had a criminal record, had a 50% risk of having a criminal record by 18. Whereas adopted children whose biological mother didn’t have a criminal record only had a 5% risk.

Question 5

what has been found about candidate genes and crime

Answer 5

two genes may be associated with violent crime. MAOA (regulates serotonin in the brain and has been linked to aggressive behaviour). The CDH-1 gene has been linked to substance abuse and ADHD. a combination of genes can create a genetic vulnerability to crime therefore crime is polygenic.

Question 6

(AO3) outline a study that demonstrates that specific genes are linked to crime

Answer 6

Tiihonen et al conducted a genetic analysis of 800 Finnish offenders, found that about 5-15% of all severe violent crime is attributable to the MAOA and CDH-13 genotypes that results in the phenotype of violent behaviour, substance abuse ect.

Question 7

outline the diathesis stress model of crime

Answer 7

A tendency towards offending behaviour may come about through the combination of genetic predisposition and biological or psychological trigger e.g. being raised in a dysfunctional environment or having criminal role models.

Question 8

what is the neural assumption about crime

Answer 8

-Evidence suggests that there may be neural differences in the brains of criminals and non-criminals. This evidence as involved individuals diagnosed with antisocial personality disorder - reduced emotional response, lack of empathy

Question 9

Outline a study that supports a neurological difference in the brain of a criminal (AO3)

Answer 9

Raine conducted many studies of the APD brain, these demonstrate that individuals with APD have reduced activity in the prefrontal cortex (regulates emotional behaviour). Found an 11% reduction in volume of grey matter in prefrontal cortex compared to controls. Also found APD had a reduced autonomic response.

Question 10

what are some neurological differences criminals may have?

Answer 10

reduced activity and volume of grey matter of the prefrontal cortex (emotional behaviour regulation)

reduced activity in the amygdala, needed for emotional processing.

mirror neurons in criminal brains need to be activated to function - may not be permenantly on/firing resulting in a lack of remorse +empathy

Question 11

what neurotransmitters have been implicated to crime and what do they regulate

Answer 11

dopamine + serotonin - involved in mood regulation, reward system, impulsivity and aggression.

Question 12

What did Keysars find about mirror neurons in individuals with APD

Answer 12

only when offenders were asked to empathise did their empathy reaction (controlled by mirror neurons) activate. suggesting they may have a neural switch that can be turned on and off unlike the ‘normal’ brain, which has the empathy switch permenantly on.

Question 13

(AO3) how does Christiansen’s study support a genetic explanation to crime

Answer 13

The higher concordance rate for MZ twins must be due to a genetic factor as they share 100% of their genes. Un addition we would expect half the concordance rate for DZ twins as they only share 50% which is demonstrated through the concordance rate of 13% for DZ. this shows a genetic predisposition in some individuals makes it more likely a person will turn to crime.

Question 14

(AO3) how does Christiansen’s study lack support for gentic explanation.

Answer 14

If crime purely due to a genes we would expect 100% concordance for MZ. never found which would suggest an alternate explanation may account for the 65% that were not found to have a concordance rate. EG stress diathesis model - interactionist model. Perhaps 35% is due to shared environment needed to trigger criminal behaviour, whereas 65% did not have same experience.

Question 15

Why are twin studies not always the most valid (AO3) -genetic

Answer 15

MZ twins share same environment both pre and post birth. Often treated the same due to similar looks by others, this will affect their behaviour. Therefore shared environment may contribute to increased concordance rate in MZ compared to DZ. Perhaps crime is due to both biology and environment, in reality it is difficult to separate.

Question 16

Why can we not identify cause and affect between neurological differences and crime (AO3)

Answer 16

Link between neural differences and APD is complex. Other factors may contribute to APD and therefore offending. Eg farrington et al studied group of adult males scored high on psychopathy. They experienced various risk factors during childhood eg neglect. It could be these early childhood experiences caused APD and osme of the neural differences. Eg reduced activity in temporal lobe due to trauma. Relationship between neural differences, APD and offending is complex.

Question 17

why is a genetic/neural explanation biologically reductionist (AO3)

Answer 17

It looks at aggression as caused by a biological abnormality and doesn’t necessarily acknowledge how this may interact with the environment and what other social and environmental factors are related to offending behaviour.

Question 18

why is a genetic/neural explanation biologically deterministic and what are the implications of this? AO3

Answer 18

the extreme side of this explanation promotes biological determinism. It takes away from people’s ability to make free choices about their behaviour and assumes that a genetic predisposition is bound to cause offending.

There are also important social implications to taking that deterministic position. Punishing people will be considered unethical if they offend due to their biology. After all, they were biologically predetermined to commit crimes and had no choice.