Neural Explanations

• Adrian Raine

  Works at the University of California. Conducted research using PET scans and found abnormalities in the brain relating to criminal violence.
• Most criminals in Raine’s studies have been diagnosed with ASPD.
• Raine discovered the criminals had reduced activity in the prefrontal cortex - the part that regulates emotional behaviour.
• Raine (2000)


  Individuals with ASPD had an 11% reduction of grey matter in their prefrontal cortex.
• Keysers (2011)


  Mirror neurons did not function in individuals with APD in their prefrontal same way as they do in normal controls. Mirror neurons allow us to feel empathy. People with APD were not completely without empathy but had to be told to feel empathy when watching a film showing an individual experiencing pain.
• However not every criminal is diagnosed with APD.
• Price (1966)

  Suggested that males with an extra Y chromosome (XYY) were super male and were over represented in the criminal population.
• Christiansen (1977)

  - Looked at 3586 twin pairs in Denmark

  - 52% concordance rate for criminality between monozygotic twins

  - 22% concordance for dizygotic
• The genetic abnormality known as the ‘warrior gene’ associated with violent and aggressive behaviour.
• Brunner et al (1993)


  - A case study on a family from the Netherlands affected by ‘borderline retardation’.

  - Five affected males were studied.

  - A mutation in the X chromosome responsible for making MAOA which can cause behavioural problems.
• MAOA is involved in serotonin , dopamine and noradrenaline metabolism. Reduced levels of these explain sleep problems and inappropriate violent and sexual behaviour.
• There is support for the diathesis stress model.
• The approach is scientifically robust as it uses technology like PET scans.
• Brunner’s study was problematic as it is difficult to untangle nature and nurture.
• Explaining criminal behaviour purely through biology is reductionist.
• Jim Fallon - Professor of Psychiatry at the University of California - has the brain structure of a serial killer. However he attributes his positive life to his upbringing.
• Crime is a social construct so it is illogical to blame biological causes.