Bio exp: Genetic and neural

• Genetic explanations suggest offenders would inherit genes/combination of genes that make them more likely to commit crime.
• Twin and adoption studies - Karl Christiansen (1977) studied over 3500 twin pairs in Denmark. Found high concordance rates for offender behaviour of 35% for identical twin males and 13% for non-identical male twins- included all twins born between 1880 and 1910 in the region of Denmark
• Crowe (1972) found adopted children whose biological mother had a criminal record had 50% risk of having criminal record at 18, otherwise there was only a 5% risk.
• Candidate genes - Trihohen (2015) conducted analysis of almost 800 finnish offenders and concluded MAOA and CDH13 genes may be better associated with violent crimes.
• MADA regulates seretonin in the brain, which is involved in mood and sleep and aggressive behaviour.
• CDH13 gene linked with substance abuse and ADHD. Found 5-10% of crimes attributable to MAOA and CDH13.
• Diathesis stress model - If genetics do not have an influence on offending, it is likely to also be partly moderated by the effects of the environment. Eg. Being raised in a dysfunctional environment ; criminal role models
• Neural explanations - evidence suggesting there may be differences in the brains of offenders and non-offenders. Involved in antisocial personality disorder + have reduced emotional responses, lack of empathy.
• Prefrontal cortex- Raine et al - conducted many studies of APD reporting several dozen brain imaging techniques demonstrating people w/ APD having reduced prefrontal cortex activity and found 11% reduction in grey matter.
• Mirror neurons are neurons that fire when an individual performs an action and when they observe another person performing the same action
• Mirror neurons - people have on and off switch to empathise w others even though they did not feel that pain.
• Genetic explanations - Suggests offenders would inherit a gene/combination of genes.
• Twin and adoption studies - Karl Christiansen (1977) studied over 3500 twin pairs in Denmark. Found concordance rates for offender behaviour of 35% for identical twin males and 17% in non-identical male twins. This included all twins born between 1880 and 1910 in a region of Denmark.
• Crowe (1972) found adopted children whose biological mother had a criminal record had 50% risk of having a criminal record at 18 whereas otherwise there was only a 5% risk.
• Mirror neurons are neurons that fire when an individual performs an action and when they observe another person performing the same action.
• Mirror neurons: offenders with APD can have empathy but just more sporadically.