Genetic and Neural Flashcards
Genetic explanation
Genetic explanations for crime suggest that would-be offenders inherit a gene, or combination of genes, that predispose them to commit crime
Twin and adoption studies
- 33% MZ concordance rates for offending
- 12% DZ
- Christiansen
- Adoptees 50% risk of criminal record if biological mother had offended (Crowe)
What are the two types of Candidate genes
MAOA
CDH13
MAOA gene
Regulates serotonin in the brain, linked with aggressive behaviour
CDH13 gene
Linked to substance abuse
Candidate genes
- MAOA
- CDH13
- Gene variants account for 5-10% of violent crime (Tihonen)
Diathesis-stress model
Genes triggered by social
Genetic explanation evaluation points- Issues with twin evidence
LIMITATION
MZ’s treated more similarly than DZ’s, explains higher concordance
Genetic explanation evaluation points- Support for diathesis-stress
STRENGTH
Conviction rate in adoptees with no biological or adoptive convicted parent (13.5%), 20% (one biological), 24.5% (both adoptive and biological).
Mednick et al
Neural explanations
Any explanation of behaviour in terms of (dys)functions of the brain and nervous system. This includes the activity of brain structures such as serotonin and dopamine
Prefrontal cortex
11% reduction in grey matter in prefrontal cortex of people with Antisocial Personality Disorder
Mirror neurons
When offenders asked to emphasise then empathy reaction (mirror neurons)
Neural explanations evaluation points- Brain evidence
STRENGTH
Link between impaired frontal lobe functioning and impulsive behaviour/inability to learn from mistakes
Neural explanations evaluation points- Intervening variables
LIMITATION
Criminal parents and early neglect cause both APD and neural differences
Farrington et al
