bio

• biological explanations - atavistic form -

  • Lombroso studied the facial and cranial features of - 389 dead convicts and 3839 living convicts 
  • Concluded that there was an atavistic form - physical markers of head and face that make criminals different from the rest of us 
• features of an offender (according to lombrosso) narrow sloping strong brow , strong jaw, high cheekbones, facial asymmetry. Extra toes, nipples or fingers. Left handed.
• • Lombroso also came up with characteristics for different offender types:
  • Murderers - long ears, bloodshot eyes, curly hair
  • Sexual criminals - glinting eyes, swollen fleshy lips 
  • Fraudsters - thin and reedy lips
• Genetic explanations of criminal behaviour:

  • 2015 Finnish study with 800 violent criminals - found 2 genes linked to violent behaviour:
  • MAOA gene - responsible for creating an enzyme which is responsible for the breakdown of serotonin and dopamine once they're no longer needed - if left to build up in the brain, they can be linked to impulsive behaviours 
  • CDH-13 gene - important for forming neural connections in the brain - mutations in this gene are linked to substance abuse, major depression and ADHD
  • People with these genes are 13X more likely to commit a crime
• Supportive evidence of genetic explanation

  • Christiansen - 3500 pairs of twins in Denmark - investigating concordance rates of offending behaviour - 35% for MZ and 13% for DZ
  • Concordance rates suggest a possible genetic element - increases external validity of explanation
• supportive evidence of genetic explanation:

  Crowe - adopted children whose biological mother had a criminal record - found a 50% chance of having criminal record by 18 - Suggests a genetic basis as these children didn't have criminal environments but still committed crimes - adds external validity 
• Neural explanations of criminal behaviour:

  • There is evidence to suggest there may be neural differences in the brains of offenders and non-offenders 
  • Research involves individuals with antisocial personality disorder (often diagnosed in offenders) - involves impulsivity, dishonesty, lack of remorse
• neural explanations -

  Abnormalities in the prefrontal cortex 

  • Prefrontal cortex helps with self-regulation, impulse control, decision making
  • Raine et al:
  • Procedure - volume of grey and white matter in the brain measured in 21 people with APD and 21 without - using mri. Also measured response to stressful situation 
  • Findings - reduced amount of grey matter (11%) was found in the prefrontal area for the APD group. They also showed a reduced autonomic response in people with APD when in a stressful situation
• limitation of Raine et al research - small sample, sample is on people with APD not criminals - only shows a link between APD and neural issues not a link with criminal behaviour
• supportive research for neural explanation

  • Burns et al:
  • Case study of a man displaying paedophilic and violent behaviours 
  • Brain scan showed a tumour on his prefrontal cortex 
  • Tumour was removed and violent paedophilic behaviours stopped 
  • Suggesting that…. Criminal behaviour is due to neural irregularities, increasing the validity of the neural explanation of criminal behaviour 
• opposing evidence of atavistic form - Goring - compared appearance of 3000 offenders and 3000 non-offenders and concludes that there was no evidence that offenders are a distinct group of people with unusual characteristics
• neural explanations - mirror neurons

  • help us empathise with others
  • Keysers - supporting evidence

  Showed offenders a film of someone in pain – only when they asked offenders to sympathise with someone in pain did they see their empathy reaction activate (this is controlled by mirror neurons in the brain)

  Suggesting APD individual are not completely without empathy but they have a neural switch that can be turned on and off – unlike the normal brain which has empathy switched on permanently