Neurochemical Theories

• What does Neurochemical theories suggest?

  Damage to the pre fontal cortex may alter a person's behaviour pattern, making them more immature and increasing their loss of self-control.
• Raine et al study Aim:


  Identify brain regions specific to offenders charged with murder/manslaughter who had pleaded not guilty by reason of insanity.
• Rain et al study Procedure:


  Participants were 41 murderers (2 female) who had been charged with murder/manslaughter and had plead not guilty.
• What did Raine et al use in the procedure?


  PET scans to highlight areas of brain activity and these results were compared to an age and gender matched control group.
• Raine et al study Findings: 


  Reduced activity for offender groups such as pre fontal cortex and corpus callosum. Also there were abnormalities in activity of limbic system - including amygdala and thalamus.
• Raine et al study Conclusion


  Offenders have abnormal brain functions. Brains of offenders are slowed due to largely reduced brain activity. Slows frontal lobes, which is linked to planning behaviour and therefore unable to consider crime and deviant consequences.
• Who was Phineas Gage and what happened to him?

  Railroad worker who survived a large iron rod that went through his head and destroyed much of the left frontal lobe. He became anti-social and started using bad language, his personality had changed.