Genetic + Neural Explanation Flashcards
What is a genetic explanation of crime?
Genetic explanations for crime suggest that would-be offenders inherit a gene, or combination of genes that predispose them to commit a crime.
What twin study was used to explain genetics of crime?
Christiansen (1977)- Studied over 3500 twins in Denmark and found concordance rates for offender behaviour were 35% for identical twins and 17% for non-identical. Included all twins born between 1880 and 1910 in a specific region of Denmark, offender behaviour checked against Danish police record, not just behaviour inherited but predisposing traits
What adoption study was used to explain genetics of crime?
Crowe (1972), found that adopted children whose biological mother had a 50% risk of having a criminal record by the age of 18. Whereas, adopted children whose biological mother only had 5% risk
What study supports role of candidate genes?
Tiihonen et al (2015)- suggests that two genes, MAOA and CDH13 may be associated with violent crime. The MAOA gene regulates serotonin in the brain and has been linked to aggressive behaviour. CDH13 gene has been linked to substance abuse and ADHD. 5-10% of all severe violent crime in Finland is attributed to the MAOA and CDH13 gene
What model could explain genetics of crime, and give explanation.
- Diathesis stress model
Such as being raised in a dysfunctional family environment or could be through having a criminal role model
What is a neural explanation of crime?
Evidence suggests there may be neural differences in the brains of offenders and non-offenders, much of the evidence in this area has involved individuals with APD (Antisocial Personality Disorder).
What is APD associated with?
- Reduced emotional responses
- Lack of feelings and empathy for others
What psychologist supported Neural explanation and what did they find?
Raine (2000). Individuals with APD through brain-imaging studies have been found to have reduced activity in the pre-frontal cortex (regulates emotional behaviour). Raine et al found 11% reduction in volume of grey matter of those with APD compared to control group.
What is the role of mirror neurons?
Those with APD can experience empathy but more sporadically then others. Keysers (2011) found that when offenders were asked to empathise with a person on a film experiencing pain their mirror neurons were activated. May have a “neural” switch which can be turned off and on, unlike normal brain where it’s constantly on
Evaluation of genetic explanation?
Limitation of twin studies is the assumption of equal environments, as they’re brought up the same. May apply more to MZ as they look the same so get treated the same, affecting their behaviour. Higher concordance for MZ may be because they’re treated more similarly.
Support for diathesis stress model of offending. Mednick et al, 13,000 Danish adoptees when neither biological nor adoptive parents have convictions, adoptees that did 13.5%. Rose to 20% when bio parents were convicted and 24.5% when both bio and adoptive. While genetic is important, environment also is.
Evaluation of neural explanation?
Support for link between frontal lobe and crime. Kandel and Freed (1986) reviewed evidence of pre frontal lobe damage and APD. People with damage has impulsive behaviour, inability to learn from mistakes. Brain damage may be a causal factor in offending behaviour.
Limitation is the link between neural differences and APD may be complex. Farrington et al studies a group of men who scored high on APD. They had various risk factors such as raised by convicted parent and neglect. Trauma could of caused reduced activity in the frontal lobe. Relationship between APD and neural differences is complex and may have other factors involved
