Raine et al.

• Raine et al. (1997)

  • Aim:
  • Investigate brain activity in Murderers' PFC
  • Pleaded not guilty due to insanity
  • Compare to matched non-murderers'
  • Sample
  • Experimental: 41 guilty referred to Uni of California for evidence they couldn’t understand jury process; 39 men and 2 women (average age 34), matched with control group
  • 6 schizophrenics
  • All took no meds for 2 weeks pre-test
  • Procedure:
  • Gave PET scan while carrying out continuous performance visual tasks for 32 mins
  • Designed to measure activity by glucose metabolic rates in frontal lobe
  • Participants got 10 min practice test first
• Raine et al. (Results)

  • Results
  • Significant difference between experimental + control groups for brain area activity
  • Lower glucose metabolism
  • Parietal cortex
  • PF lobe
  • Corpus callosum
  • L amygdala
  • L medial temporal lobe, inc hippocampus
  • Higher
  • R amygdala
  • R thalamus side
  • Occipital lobe
  • R medial temporal lobes, inc hippocampus
  • Conclusion
  • Lower; link to low self-control, high aggression + impulsive
  • Abnormal limbic system; can't to modify behaviour by consequence
  • Amygdala, hippocampus + PFC govern emotionality
• Raine et al. (Evaluation)

  Generalisability

  • For behaviour studied sample was representative
  • Largest sample to be studied this way (men mostly do violent crime)

  Reliability

  • Well-controlled
  • Matched for sex, age, MH and none took any meds 2 weeks pre-study so I didn't impact their results or performance
  • PET scans:
  • Reliable + objective
  • Quantitative results
  • Replicable
  • But generated images are based on location of certain brain ‘landmarks’ different for all

  Validity

  • PET scans:
  • Difficult to interpret accurately (especially '97, images unclear)
  • Cause and effect difficult to verify
• Raine et al. (Ethics)

  • Obtained Consent + caused no distress
  • Experimental group already found guilty; not distressed by idea they may commit extreme violence (already had)
  • Approved by ethics committee
  • May have felt under duress; look for evidence for mitigation of their crime
  • If participants mentally ill (e.g. had schizophrenia) may not have capacity to give fully informed consent