biological explanations : Genetic and Neural explanations

Question 1

genetic explanation of offending manily focus on the

Answer 1

heritability and role of candidate genes in the development of criminal behaviour

Question 1

for example Christiansen et al 1977 found that

Answer 1

concordance rates of
33% MZ twins (87)
12% DZ twins (147)
suggests that there is a moderate genetic or heritable basis of criminal behaviour

Question 2

however the concordance rates for MZ twins is not 100% and so this suggests that

Answer 2

an interaction between the environment and genetics together produces the outcome of criminality as suggested by Mednick et al , and so the traditional diathesis stress model can be used to account for this

Question 3

candidate genes each represents slight genetic variations which increase the risk of developing criminal behaviour , in thus case as suggested by Tiohonen et al

Answer 3

abonromalties in the MAOA and CDH-13 genes , which both code for neurotransmitters such as serotonin and dopamine and so are also implicated in the development of ADHD , increases the likelihood of becoming a criminal by 13-hold.
Further support to the role of a genetic diathesis in the development of criminality.

Question 4

Neural explanations mainly focus on indviduals with anti social personality disorder (APD) a disorder which is very common amongst criminals , for example Raine et al found that

Answer 4

criminals have a lower volume and activity level (11% reduction) in the prefrontal cortex which is responsible for logical thinking and decision making.
therefore , this supports the idea that criminals may have difficulties in regulating their emotions and so make irrational decisions.

Question 5

Neural abnormalities associated with criminality were further supported by Keyser’s et al , who found that criminals appear to have a

Answer 5

’ neural switch ‘ which they can use to turn their capacities for empathy on or off .
This may explain why and how criminals lack empathy towards their victims.

Question 6

• A key methodological issue with the use of twin studies as a means of investigating the genetic basis of behaviour is that such studies assume that

Answer 6

the only difference between twins is the amount of genetic information they share. This is an incorrect assumption and would be better addressed through the use of an interactionist approach. For example, the fact that MZ twins are likely to share the same environment as opposed to normal siblings may explain why MZ concordance rates are higher than for normal siblings, despite both sharing 50% of their genes. This suggests that causal conclusions about the genetic basis of criminality have incorrectly been reached.

Question 7

+ strong support for the use of a diathesis-stress model in explaining criminality comes from Mednick et al

Answer 7

After analysing the court convictions of 14,427 adoptees with adoptive and biological parents, the researchers concluded that 1“siblings adopted separately into different homes tended to be concordant for convictions, especially if the shared biological father also had a record of criminal behaviour”. This supports the idea that criminality is only likely to be an outcome if a genetic susceptibility is paired with environmental (criminal) stressors, as predicted by the diathesis-stress model.

Question 8

• the focus on the role of genetics and neural activities as a means of explaining criminal behaviour suffers from the problem of biological reductionism as suggested by

Answer 8

Katz et al (2007). Although it does appear that criminality runs in families, so do other risk factors associated with criminality e.g. a high frequency and intensity of exposure to pro-criminal attitudes (similar to Sutherland’s Differential Association Theory), a lack of educational opportunities, economic deprivation etc. Therefore, it is important not to stereotype children from criminal families as ‘criminal’ as this may lead to the realisation of self-fulfilling prophecies.