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Biology. Is there any evidence that criminal behaviour has a biological cause?. The theory of biology.
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Biology Is there any evidence that criminal behaviour has a biological cause?
The theory of biology • The basic assumption here is that criminals are biologically different to non-criminals. In particular, some bio-psychologists argue that special structures inside the brain control our social behaviour. People without these structures may become criminals. • However, these theories are often reductionist and deterministic and can only explain certain types of crime. • What crime could you link to biological reasons and why?
Evolution: • It has been shown that males often commit crimes more than females. • It has been suggested that this could be due to an evolutionary trait. • Males who were aggressive, could fight, run and take risks, etc, would survive more in times when such behaviours were necessary, those who were not aggressive died and so the necessary genes were passed on.
Cesare Lombroso's (1835-1909) theory of anthropological criminology • What do we know?
Theories of Biology Raine, Bruner, Daly and Wilson
Learning outcomes • Brain dysfunction (Raine, A. (2002) ‘The role of prefrontal deficits, low autonomic arousal, and early health factors in the development of antisocial and aggressive behaviour in children’, Journal of Child Psychology and Psychiatry 43, 417–34) • Genes and serotonin (Brunner et al. (1993) ‘Abnormal behaviour associated with a point mutation in the structural gene for monamine oxidase A’, Science 262 (S133), 578–80) • Gender (Daly, M. and Wilson, M. (2001) ‘Risk-taking, intrasexual competition, and homicide’, Nebraska Symposium on Motivation 47, 1–36)
a) Outline how brain dysfunction can explain criminal behaviour • b) Evaluate individual (biological) explanations of criminal behaviour January 2011
a) Outline a biological explanation of why males commit more crimes than females. • b) To what extent does the biological approach provide an explanation of criminal behaviour? January 2010
Raine (2002) Understanding the development of antisocial behaviour in children
True all of the time? Some of the time? Never? 1 The brain controls every single function of the body. 2 Your genetic inheritance determines your behaviour. 3 The position of a monozygotic twin in the womb can influence that twin's personality. 4 The brain is thought of as being 'plastic' which means it is rigid and cannot change. 5 Children aged 3-10 have less efficient brains than adults. 6 Changing your thinking patterns can change the structure of your brain (ie beating addiction, OCD etc.)
Is crime in the genes? * Can violence be seen as a disease, in the same way that alcoholism is now viewed? * Are we programmed – think evolution – to be violent?! * Since early 1990's science has 'swung' more towards genetic explanations for behaviour. * Could a genetic excuse be used by a lawyer to get their client off a murder charge?
Genes/biology or something else? • * A man who has suffered head injury in a road accident beats up another man in an unprovoked attack. • * A teenage girl with an average IQ participates in vandalism with her friends. • * A body-builder who experiences extreme road rage. • * A child with ADHD who is loud and abusive.
Personality change via brain damage • Gage, 1894. • Railway worker – catastrophic damage to prefrontal lobes caused by a metal bolt catapulting through cheek and up through eye into brain. • Recovered physically but went from being a sober, quiet family man to a violent drunk. • Prefrontal lobes are one of ‘newest’ brain areas – keep behaviour in check, moderate impulses.
Key study: Raine • Ongoing studies, longitudnal. • Raine believes that sudden, unpremeditated murder could have a biological cause – abnormality in brain’s metabolism. • Low physiological arousal might mean an individual seeks ‘thrills’ in increasing measures = criminal behaviour.
physiological – Raine 1997 • PET scan: • less active: forebrain and corpus callosum (executive control, puts 'brakes' on behaviour) • Asymmetric differences Amygdala, hippocampus, thalamus (emotion/fear) • Raine 2: boys’ physiology • Low heart rate and skin resistance @ 14 • = good predictor of criminal record @ 21 fast slow
Adolescents are all criminals… • * Blakemore & Choudry (2006) – adolescent brain still forming its final connections in pre-frontal lobes (complete in early 20’s) • * Raine (2002) – pre-frontal activity lower in impulsive individuals who are likely be anti socialand aggressive. • * Birth complications, poor parenting, physical abuse, smoking, substance abuse all add to risk… • Can you see how this complements the Farrington study?
Aim: - • To make a multi-factor approach to understanding antisocial and aggressivebehaviour in children. • What different biological muliti-factor approaches can you think of that could explain a persons antisocial behaviour? • Mind map with a partner…
Procedure: - • A meta-analysis (results of several studies) of a selection of articles covering neuropsychological, neurological and brain-imaging studies as they relate to anti-social behaviour in children. • Covering several studies that address the situation • One of which is purely based on resting heart rates
Findings: - • A low resting hearty rate is a good predictor of an individual who will seek excitement to raise their arousal level, creating a fearless temperament. • The adolescent brain is still forming its final connections in the pre-frontal lobe right up until the early twenties. • Activity in the pre-frontal lobes of impulsive individuals, who are more likely to be antisocial and aggressive, is lower • Birth complications and poor parenting with physical abuse and malnutrition, smoking and drinking during pregnancy all add to the risk. • (This is a strength of this research as it considers other factors, not just biology, so it is less reductionist than other studies
The frontal lobes are involved in several functions of the body including: • Motor Functions • Higher Order Functions • Planning • Reasoning • Judgement • Impulse Control • Memory
Conclusion: - • Raine concludes that early intervention and prevention may be an effective way of reversing biological deficits that predispose to antisocial and aggressive behaviour. • Agree or disagree?
Key points • Background: This article selectively reviews the biological bases of antisocial and aggressive behavior in children with a focus on low autonomic functioning (this nervous system controls heart rate, digestion, danger/stress) prefrontal deficits, and early health factors.
Key points • Low resting heart rate is thought to be the best-replicated biological correlate of antisocial and aggressive behavior in child and as a result children are fearless, stimulation-seeking and have bad temperament. • Evidence from neuropsychological, neurological, and brain imaging studies converges on the conclusion that prefrontal structural and functional deficits are related to antisocial, aggressive behavior throughout the lifespan. • A prefrontal dysfunction theory of antisocial behavior is advanced. • It argues that this prefrontal dysfunction causes a lack of inhibitory control over antisocial, violent behavior that peaks at a young age
Key points • Birth complications are selectively associated with later violent behavior, especially when combined with adverse psychosocial risk factors for violence. • Cigarette smoking during pregnancy may increase the risk for antisocial and violent behavior in later life by disrupting nora-adrenaline (stress hormone) functioning • Malnutrition during pregnancy is associated with later antisocial behavior and may be mediated by protein deficiency
Key points • Conclusions: It is argued that early health intervention and prevention studies may provide the most effective way of reversing biological deficits that predispose to antisocial and aggressive behavior in children and adults
Remember • Low resting heart rate • Fearless temperament • Birth complications • Lower activity in prefrontal lobes • Poor parenting • Drinking and smoking in pregnancy
Consider the following… • Raine’s more recent work has led him to believe that biological predispositions are ‘switched on’ by environmental conditions. • If these environmental conditions do not exist, then the child is much less likely to turn to crime. • What does this suggest about crime prevention?
Consider the following… • A major concern about all biological explanations is the ‘labeling effect’, leading to certain expectations and a self-fulfilling prophecy that someone's biological make up will predispose them to crime • How can this be resolved ethically so that the researchers knowledge is used for the benefit of society?
Bruner A study of violence in a family of genetic abnormality.
Background: • Genes are the building blocks of DNA and tell our bodies how to grow and develop. • Our genes do not know anything about the laws and constructs of society so criminality is not directly affected by our genes. However, genes can give people predispositions- a natural, built-in tendency to behave in a certain way- for example taking risks, being aggressive or selfish. • These predispositions may lead to a person behaving in a way that leads to criminal behaviours.
Aim: • To study a family where males were affected by a syndrome of borderline mental retardation and abnormal violent behaviours.
Methodology: • A case study of a family from the Netherlands. • 5 affected males were studied who showed behaviours such as impulsive aggression, arson, attempted rape and exhibitionism. • Data was collected from the analysis of urine samples collected over a 24 hour period.
Findings: • The tests showed disturbed monoamine metabolism associated with a deficit of the enzyme monoamine oxidase A (MAOA-). • MAOA is an enzyme that degrades neurotransmitters, such as dopamine, norepinephrine, and serotonin. • A mutation was identified in the X chromosome of the gene responsible for the production of MAO-A. • MAO-A is known as the ‘warrior gene’
Conclusions: • MAOA is involved in serotonin metabolism. • An impaired metabolism of serotonin is likely to be responsible for mental retardation and could be linked to the aggressive behaviour.
Issues: • Generalisability • Small sample- only 5 boys from 1 family • Could this just be an ‘odd’ family?- not like the rest • Quantitative data • Urine samples were taken which increases the objectivity.
Debates: • Reductionism vs Holism • Puts behaviours down to genes and mutations within the body • Psychology as science • Objective measures
Daly and Wilson Investigation of gender-related life-expectancy.
Background: • In all cultures, young males appear more often in crime statistics than any other group. • Daly and Wilson noticed that young male offenders have a short term horizon where they want instant gratification. They also have a short lifespan expectation die to the risky behaviour that they engage in.
Aim: • To find out if homicide rates would vary as a function of local life expectancy in Chicago.
Methodology: • A correlational study using survey data from police records, school records and local demographic records in Chicago.
Why Chicago? • Chicago is an unusual American city because it is divided into 77 distinct community areas or neighbourhoods. • These areas have fairly clear cut boundaries and their own social and economic characteristics. • The researchers took their data from a recent population census and compared it to police and school records on crime, delinquency and truancy. • They focussed on the communities that had a low average life expectancy for males aged 54-77 years.
Findings: • The results showed that life expectancy was a good predictor of neighbourhood homicide rates. • There was a negative correlation; the lower the life expectancy, the higher the homicide rate. • The correlational coefficient was -0.88, which is very strong. • Daly and Wilson suggest that young men in these areas have the ‘short term horizon’ described earlier. They want instant gratification rather than delayed pleasure and expect to live short lives and discount the future.
Findings: • Another finding was a negative correlation between truancy from school and life expectancy. This could be explained by a short term horizon again. • The boys see little point in working hard at school because they do not imagine long futures for themselves and their parents don’t force them to attend because they also operate on a short term horizon. • The payoff is then that young males who skip school and break the rules will have more potential friends, compensating for them dying younger.
Conclusions: • Young men from disadvantaged neighbourhood expect to live shorter lives, therefore are more likely to engage in risky behaviours. • These findings can be explained by social factors such as poverty and inequality.
Issues: • Correlational study • Does not show cause and effect • Reliability • Data gathered from police and school records
