BIOLOGICAL EXPLANATIONS: GENETIC AND NEURAL AO1 & AO3

Question 1

Genetic (Biological Explanation)

Answer 1

• Genetic explanations (GE) for crime suggest that offenders inherit a gene(s) that predispose them to commit crime.
• Biopsychologists use twin studies + brain scanning techniques to look at genetic explanations for crime.
• There has been focus on 2 candidate genes: MAOA gene (which controls dopamine/serotonin in the brain) and CDH-13 gene (linked to substance abuse).
• Therefore the CDH-13 could lead people becoming more violent due to this substance abuse, and potentially assault/GBH.
• Lange investigated 13 MZ twins and 17 DZ twins where one of the twins in each pair has spent time in
  prison, and found that 10 of the MZ twins had a co-twin that had also spent time in prison compared to 2 of the DZ twins

Question 2

Neural explanations (NE)

Answer 2

• propose that criminals and non-criminals have differences in brain structures as well as neurotransmitter levels.
• Reduced activity in the prefrontal cortex means it does not regulate emotions, inhibitions and morality which means people cannot regulate things like anger, impulsiveness, and knowing right from wrong.
• Mirror neurons respond equally when we perform an action and when we witness someone else perform the same action.
• Mirror neurons are dysfunctional in the brains of criminals as it’s not an automatic response for them and so they do not feel empathy/sympathy when committing crimes, such as rape/murder.
• Lastly, the disruption to levels of neurotransmitters in the brain
  has been linked to criminal behaviour.
• For example, low levels of serotonin (linked to mood and impulsiveness), as well as increased dopamine in the brain (linked to pleasure/reward feeling) which entices them to actively seek thrill seeking experiences (running from police) again due to reward feeling

Question 3

Diathesis stress model

Answer 3

• concordance rates are often far lower than 100% suggesting there is influence from the environment.
• Offending may be due to a genetic predisposition and activated by a psychological trigger e.g. dysfunctional family/ criminal role models.

Question 4

lacks internal validity

Answer 4

• One limitation of the GE is that supporting research lacks internal validity.
• For example, early twin studies, such as Lange’s research, made judgements related to zygosity (whether the twins were MZ or
  DZ) were based on appearance rather than DNA testing.
• This means the Lange research is a little flawed,as you can have non identical twins that look alike, and because there was no DNA testing we are unsure if Lange correctly identified the twins as being MZ or DZ twins.
• This is a disadvantage as it decreases the validity of research, and therefore casts doubt on his findings.
• However, research by Christiansen supports the idea that offending may have genetic components therefore findings are still quite valid.

Question 5

• One limitation of GE is that it’s difficult to generalise from twin samples.

Answer 5

• For example, the sample size used in twin studies are generally small and also twins are an unusual sample in themselves.
• This means the twins’ samples are not representative of the whole population.
• This is a disadvantage as we are unable to generalise the findings to the wider population.
• Furthermore, you can’t differentiate nature from nurture.
• Twins are reared in the same environment, especially identical twins as they are sharing the same post/prenatal environment, so we are unable to tell if something is due to nature or nurture

Question 6

• One limitation of the biological approach is that it’s biologically reductionist, as it doesn’t take all factors into account.

Answer 6

• For example, explanations that reduce offending behaviour to a genetic or neural level maybe inappropriate and overly simplistic.
• Crime runs in families but it is difficult to differentiate the effects of genes and neural influences from other possible factors.
• Findings from twin studies that don’t have a 100% concordance rate shows its more than just biology.
• This means trying to explain criminality just from a person’s biology and completely ignoring other factors e.g environment, poverty will not give us a holistic understanding of criminality.
• Furthermore, a better explanation is the diathesis stress model that suggests genes create a vulnerability which can be triggered by the environment, which provides a more holistic explanation of why people commit crime

Question 7

• One limitation of the biological approach is that it’s highly biologically deterministic explanation.

Answer 7

• For example, the BA suggests that criminals are predisposed to committing crime which goes against our criminal justice system (CJS). CJS based on accountability, and claiming that crime is the result of carrying a criminal gene removes the notion of free will from the picture.
• This means we are unable to hold criminals accountable for their actions, as in order to do that we have to consider free will.
• Furthermore, trying to link crime to biology opens itself to eugenics policies. If something biological is the only result of a crime the only way to get rid of it is to kill the gene off. Whereas, when looking at environmental factors you can treat them in less extreme ways, such as/therapies

Question 8

twin studies

Answer 8

• One limitation of GE is that it’s difficult to generalise from twin samples.
• For example, the sample size used in twin studies are generally small and also twins are an unusual sample in themselves. This means the twins’ samples are not representative of the whole population.
• This is a disadvantage as we are unable to generalise the findings to the wider population.
• Furthermore, you can’t differentiate nature from nurture. Twins are reared in the same environment, especially identical twins as they are sharing the same post/prenatal environment, so we are unable to tell if something is due to nature or nurture.