5. Biological Explanations: Genetic & Neural Explanations Flashcards
What is the basic idea behind genetic explanations?
Would-be offenders inherit a gene, or combination of genes, that predispose them to crime.
Which twin study supports the genetic explanation?
Lange (1930) - 13 identical MZ and 17 non-identical DZ - one twin in each pair spent time in prison - 10 of MZ twins had a co-twin in prison only 2 DZ twins did - therefore genetic factors must be significant in causing crime
What are candidate genes?
These are the groups of genes deemed responsible for causing criminality
Who did a significant candidate genes study and what did they find?
Tiihonen et al. (2014) - analysed 900 offenders - found the MAOA gene and CDH13 were associated with aggressive behaviour and attention deficit disorder respectively - individuals with the high risk combination were 13 times more likely to have a history of violent behaviour - not replicated
What is the diathesis-stress model?
This is the idea that genetics may create a disposition for criminality but there needs to be an environmental stimulus also.
What is the basic idea behind the neural explanations?
Evidence suggest there may be neural differences in the brains of criminal and non-criminals.
What is anti-social personality disorder?
This is a condition associated with reduced emotional responses, a lack of empathy for the feelings of others - characterises many convicted criminals.
Who has conducted research into the neural explanations for criminality?
Adrian Rane
What studies did Rane conduct and what were his findings?
Rate used brain-imaging to study the prefrontal cortex - he found that individuals with APD have reduced activity in the prefrontal cortex (the part of the brain that regulates emotional behaviour) he also found an 11% decrease in the quantity of Grey Matter in the PFC of APD sufferers compared to controls.
What are mirror neurons and how are they important in the neural explanation for criminality?
Mirror neurons are part of the brain that fire in order to stimulate feelings of empathy - the suggestion is that criminals mirror neurons only fire when explicitly asked to meaning criminals have limited empathy.
Who conducted a study into mirror neurons and what did they find?
Keysers et al. (2012) - she did a study on mirror neurons - finding criminals have the ability to simply ‘switch on and off’ there feelings of empathy.
What are the evaluation points for the genetic and neural explanations of criminality?
- Problems with Twin Studies - Lange’s study was limited as whether twins were MZ and DZ was based purely on appearance - less reliable
+ Support for the diathesis-stress model - Mednick et al. (1984) - a study of over 13,000 Danish Adoptees - looked at criminal records - when neither bio. or adoption. parents had criminal record - 13.5% - when one did - 20% - when both did - 24.5% - suggests that while genetics are important there is also an environmental element - Biological Reductionism - criminality is complex, explanations that reduce offending behaviour to a genetic or neural level may be inappropriate and overly simplistic.
- Biological Determinism - if we consider ppl to have ‘criminal genes’ they can’t be held responsible for their actions - justice system collapses.
