Neural explanation

• Neural chemical:


  Increased levels of dopamine- dopamine is linked to arousal and reward-seeking behaviour.

  Unstable levels of serotonin- serotonin is important for mood regulation so if it’s unstable it can lead to impulsive behaviour and criminality. 
• Structural differences: 


  Limbic system- area of the brain which helps to regulate emotions.

  Amygdala- part of the limbic system and processes emotional information.

  Research suggests a smaller amygdala is linked to lack of empathy in offenders- which may explain why they do not show guilt or remorse.
• Key study: Raine et al.


  Aim: identify regions specific to offenders charged with murder of manslaughter, who had pleaded not guilty by reason of insanity. 
• Key study: Raine et al.

  Method: pls were 41 murderers (2 females) who had been charged with murder or manslaughter and had pleased not guilty by reason of insanity. The researchers used a PET scanning method to highlight areas of the brain activity and these results were compared to an age and gender matched control group. 
• Key study: Raine et al.

  Results: found reduced activity for the offender group in areas such as the prefrontal correct and the corpus callosum (nerve fibres responsible for swift communication between the hemispheres). Additionally, there was abnormalities in the activity of the limbic system, incl the amygdala and thalamus. 
• Key study: Raine et al.

  Conclusion: there is indication that offenders (esp violent offenders) have abnormal brain functions when compared to normal controls. As there is largely reduced activity it would suggest that the brains of offenders are slowed and perhaps unable to make the swift decisions to react appropriately in certain situations. E.g the frontal lobes are linked to planning behaviour therefore, perhaps the decreased prefrontal cortex activity indicated that offenders are unable to consider the consequences of their actions and control behaviour
• A strength of neural explanations is there is support for the link between crime and the frontal lobe. Kandel and Freed reviewed evidence of frontal lobe damage (incl the prefrontal cortex) and antisocial behaviour. People with such damage tended to show impulsive behaviour, emotional instability and an inability to learn from their mistakes. The frontal lobe is associated with planning behaviour. This supports the idea that brain damage may be a casual factor in offending behaviour. 
• weakness is biologically deterministic. theory suggests people are born with disposition for criminal behaviour based on physiology and free will has no influence over behaviour. Lombroso’s theory claims people with atavistic form will inevitably become criminals/advocates people may be born ‘evil’. has socially sensitive consequences in more ways than one. suggests criminal behaviour is inevitable,renders strategies for rehabilitation/reducing crime, claim criminal behaviour isnt result of free will suggests society unable to blame offenders for behaviour, conflicts with legal system.