genetic and neural explanations

• genetic explanations of criminal behaviour focus on heritability and the role of candidate genes
• Christiansen et al - found there were concordance rates on criminal behaviour for mz twins at 35% compared to 13% in DZ twins (males). this supports a genetic basis for criminal behaviour, yet as concordance rates for mz twins are not 100% we would need to use a diathesis stress model.
• Role of candidate genes - Tiihonen et al proposed abnormalities in candidate genes can explain offender behaviour. MAOA and CDH-13 genes are responsible for the coding of neurotransmitters such as dopamine and seratonin. abnormalities in these are associated with ADHD which In turn can cause criminal behaviour due to the 13 fold.
• neural explanations - mostly focus on antisocial personality disorder, proposed by Raine et al who claimed most criminals display this personality type. he found an 11% reduction in the volume and levels of activity in the prefrontal cortex, which is responsible for logical and rational decision making. this explains why criminals have trouble regulating emotions and making rational decisions

  • research has also found that criminals have 'neural switches' which can turn their empathy on and off
• A03

  + research support for the use of the diathesis-stress model - mednick et al studied 14,000 adoptees and found that 15% of sons that were adopted into a criminal family became criminals , compared to 20% whose biological parents were criminals. this therefore suggests that both environmental and biological factors can influence the development of criminal behaviour therefore stressing the importance of a diathesis-stress model
• A03

  -explanation has been criticised as reductionist- while evidence clearly shows a degree of influence that genetic and neural factors have on explaining criminal behaviour, it fails to take into consideration economic deprivation, exposure to crime and lack of education that also influences criminal behaviour. therefore it lacks validity as its not comprehensive.
• A03 +real world application - research into neural abnormalities e.g low levels of serotonin which can lead to aggression can be used to find ways of treating this. e.g artificial sweeteners can contribute to a lack of serotonin production meaning in prisons, they can alter prisoners diets with more natural and nutritional food choices which can alter brain chemistry and allow aggression levels to decrease and rational thinking to increase. similarly treatments can be produced to stimulate serotonin production. therefore, research is vital in changing prison behaviour