2.1 Flashcards
what are the physiological theories of crime
Lombroso’s Born Criminals theory
Sheldon’s Somatypes theory
what is the key idea of Lombroso’s Born Criminals theory
criminals are physically different from non criminals
how did Lombroso study to get to his conclusion
measured many faces and head of criminals
what were Lombroso’s findings
criminals are more likely to have large jaws, long arms and aquiline noses
what does atavism mean in Lombroso’s theory
criminals are a throwback to primitive stage of evolution - pre social, impulsive, reduced sensitivity to pain
what did Lombroso find in his further work
insane criminals, epileptic criminals, criminaloids - product of environment
what are the strengths of Lombroso’s theory
- first person to study crime significantly
- shows importance of clinical and historical records of criminals
- helps to focus on how prevention not punishment
what are the limitations of Lombroso’s theory
- no further evidence to link facial features and criminality
- did not compare with control group of non criminals
- racist, equates criminals with savages/ non western society
what are the key ideas of Sheldon’s somatypes theory
Somatype (body type) is related to criminality
How did Sheldon study to get his conclusion
looked at body types and compared with likelihood of criminality
what were Sheldon’s findings
Mesomorphic somatypes are most likely to be criminals
what was the reason for for Sheldon’s findings
attracted by risk taking and their physique and assertiveness are important assets in crime
strengths of Sheldon’s theory
- other studies replicate findings
- most serious delinquents has most mesomorphic bodies
what are the limitations of Sheldon’s theory
- criminality likely to be a combination of biology and environment
- mesomorphic build may be result of criminality
- social class might be true cause of offending and mesomorph
- mesomorphs are more likely to be labelled
what is the key idea of the twin studies
if crime is genetic - identical (Mz) twins should have identical criminality
what were the findings of the twin studies
Christiansen - Concordance in criminality Mz - 52% vs Dz - 22%
what was the key idea of the adoption studies
Adoptees share environment of adoptive parents but the genes of biological parents. If genetic criminality will match biological parents more
what were the finding of the adoption studies
Mednick et al - birth parent concordance - 20% vs adopted parent concordance - 14.7%
strengths of the twin and adoption studies
- twin and adoption studies give some support to genetic explanations
- adoption studies overcome the problem of isolating genes and environment
- research design of adoption studies is logical (nature vs nurture)
limitations of the twin and adoption studies
- if criminality was only genetic MZ twins would have 100% concordance
- it is impossible to isolate genetic effects fully from environmental ones
- adopted children often placed with similar families to their birth family
what is the key idea of Jacobs XYY study
XYY syndrome in males makes them genetically predisposed to criminality
how did Jacob Study to get his results
compared the rate of XYY in imprisoned criminals with general population
what were Jacob’s findings
higher than average proportion of inmates has XYY
what are the feature of an XYY person
very tall
well built
low intelligence
high aggression
violent
strengths of Jacob’s XYY study
- Jacob et al found association with XYY and violent prisoners
- Price and Watmore found links with XYY and property crime
limitations of Jacobs XYY study
- having the syndrome doesn’t mean that is the cause of crime
- XYY men fit stereotype of violent offenders - labelling theory
- low intelligence of XYY may give higher chance of being caught
- syndrome is too rare to explain much crime
brain injuries key idea
brain injury can change the personality of someone and are more common in prisoners
brain injury case study
Phineas Gage - metal rod through the brain survived but personality changed
brain disorder key idea
some brain diseases have been linked with criminal or anti-social behaviour. dementia, encephalitis, brain tumours, Huntington’s chorea
brain injury and disorders EEG readings
some studies show abnormal EEG reading in psychopathic criminals
strengths of brain injuries and disorders
- a few extreme cases do show brain injury leading to changes in behaviour including personality
- some correlation between abnormal EEG readings and psychopathy
- prisoners are more likely than non - prisoners to have a brain injury
limitations of brain injuries and disorders
- crimes caused by brain injury or disease are rare, original personality is more important
- abnormal EEG not necessarily the cause and not found in all psychopaths
- prisoners high likelihood of brain injury may be affect of criminality not cause - e.g. getting into fights
key idea of biochemical explanations
biochemical substances and processes are linked to criminality
how do male sex hormones link to criminality
Ellis and Coontz testosterone peaked in their early 20s same as their criminality
how do female sex hormones link to criminality
PMT and PND lactation all used as defence in court as they affect mood and self-control
how does blood sugar affect crime
hypoglycaemia is linked to aggression
how does substance abuse affect crime
prescription and illegal drugs and alcohol linked to crime as it can lead to increased aggression
how do other substances affect crime
lead, tartrazine linked to hyperactivity
vitamin B deficiency linked to erratic behaviour
strengths of biochemical explanations
- biochemical factors are recognised in court
- sex hormones, alcohol, drugs all known to affect behaviour
limitations of biochemical explanations
- biochemical processes may need an environmental trigger too
- some studies find testosterone not linked to physical aggression
- infanticide may be caused by isolation rather than hormones
