Biological Explanations Flashcards
what does the atavistic form refer to
refers to features which belong to a more primitive era
what is evolutionary throwback
any behaviour or feature that should have died out due to the processes of evolutionary adaption
historical approach
lombroso
suggested criminals were genetic throwback
a primitive subspecies who were biologically different from non criminals
his theory today is described as speculative and naive
what was Lombroso biological approach to offenders
he believed that offending behaviour was innate and therefore an offender was not to blame for their actions
he saw offending as a natural intendency rooted in genes of those who engage in it
what did the atavistic form include
they had particular physiological markers linked to particular types of offence
they had biological determined atavistic characteristics that made them physically different
examples of cranial characteristics the atavistic form include
narrow sloping brows
strong prominent jaw
high cheekbones
facial asymmetry
what physical markers and traits does Lombroso believe offenders have
dark skin
existence of extra toes, nipples and finger
insensitivity to pain
use of slang
tattoos
unemployment
Lombroso went on to categorise particular types of offenders in terms of their physical and facial characteristics. what are they
murders were described as having blood shot eyes, curly hair long ears
sexual deviants had glinting eyes, fleshy lips, projecting ears
lombroso research
he examined facial and cranial features of hundred of Italian convicts
the features were key indicators of criminality
examined almost 400 dead convicts and b400 living and concluded 40% of criminal acts committed by people atavistic characteristics
Evaluation of lombrosos legacy
Strength
Was one of the first medical professionals to realise criminals could be studied scientifically making his theory influential
Counter argument
Delisi questioned lombrosos legacy drawing attention to the racist undertones (curly hair, dark skin) this view fitted 19th century eugenic attitudes
This suggest some specks o his theory was highly subjective rather then objective, influenced by racial prejudices of the time
Research evidence to disprove atavistic form
Charles goring
- used comparison between 3000 offenders and 3000 non offenders
- concluded there is no evidence that offenders are a distinct group with unusual facial and cranial characteristics
This questions whether criminality is innate and that offenders can be physically distinguished between rest of population
Limitation of lombrosos method
Was poorly controlled
- failed to contol important variables
- did not compare offender sample to non offender control group
- this means no control over confounding variables eg research has showed links between crime and social conditions eg poverty, poor education outcomes
What is genetic explanations of offending behaviour suggest
Genetic explanations for crime suggest would be offenders inherit a gene or combination of genes that predispose them to commit crime
What’s one way to investigate a genetic explanations of offending of offending behaviour
3500 Twins studied to find concordance rates for offender behaviour
- 35% for MZ twins
- 13% for DZ twins
What did Crowe find about criminality links in families
Adopted children whose bio mother had a criminal record - 50% chance of criminal record by 18
Adopted children. Whose bio mother didn’t have criminal record - 5% chance of
Candidate genes of criminality
Tilhonen et al
Genetic analysis of 800 Finnish offenders
Suggested two genes may be associated with violent crime
Analysis found about 5-10% of all severe violent crime in finlands attributable to the MAOA ans CDH13 genotypes
What do the two genes associated with violent crime do to the individual
- MAOA: regulates serotonin in the brain and is linked to aggressive behaviour
- CDH13: has been linked to substance abuse and attention deficit hyperactivity disorder
Diaries stress model in relation to offending behaviour
If genetics do have influences on offending it is likley that it is moderated by the effects of the environment
Tendency towards offending behaviour may com about through genetic predisposition and biological or psychological triggers
Neural explanation of offending behaviours
Revolve around the idea that the brain structure or neurochemistry of an offenders brain is different to a non offenders brain
Prefrontal cortex
Raine conducted studies of the antisocial personality disorder
Brain imaging studies show people it’s APD have reduced activity in the prefrontal cortex, part of brain regulating emotional behaviour
They also found 11% reduction in volume of grey matter
Mirror neurons
keysers found
- only when offender were asked to empathises did their empathy reaction controlled by mirror neurons in brain activate
Suggest APD individuals are not totally without empathy by may have a neural switch that can be turned on and off unlike normal brain that has emaohy permenatly switched on
Issue with twin studies being used as genetic evidence of offending behaviour
Limitation of Using twin studies being used as genetic evidence is the assumption of equal environments
The shared environment assumption may apply more to MZ twins than DZ twins because MZ tiwns are identical they are treated more similarly which affects their behaviour
Therefore higher concordance rates for MZ twin studies may simply be because they are treated more similarly than dz twins
One strength is Support for the diathesis stress model of offending why
Mednick et al
When neither bio or adoptive parents had convictions number of adoptees was 13.5% which is high
Figure rose to 24% when both adoptive and bio parent had convictions
This show that genetic inheritance plays an important role in offending but environmental influence is clearly also important providing support for diatheis stress model of crime
Strength for neural explanation
Strength is support for the link between crime and the frontal lobe
Kandel and freed reviewed evidence of frontal lobe damage and antisocial behaviour
People with damage show impulsive behaviour, emotional instability and inability to learn from their mistakes
This supports the idea brain damage may be casual factor in offending behaviour
What is a limitation of neural explanation - intervening variables
Link between neural differences and APD may be complex
Other factors can contribute to APD and to offending
Farringtin et al studied group of men who scored high on psychopathy these individuals exigences various risk factors during childhood
Could be said early childhood experiences causes APD and some neural differences
Suggest relationship between neural differences, APD and offending is complex and there are many variables that avhe an impact
Limitation of biological approach for offending behaviour
Suggests that offending behaviour is determined by genetic/neural factors which cannot be controlled by the person so a person should not be held responsible for a crime
This removes free will leading a self fulfilling prophecy for idividuals
Limitation of neural explanation for offending explanations - link of studies
Many studies link genes with anti social personality disorder or substance abuse but not necessarily offending this questions the validity
