Methodology

• Methodology 1

  • A quasi experiment
  • Matched pairs design
  • Wanted to measure brain differences between individuals who were NGRI or not
• Methodology 2

  • IV = NGRI or not
  • DV = Brain differences
• Methodology 3 - Experimental group

  • Murderers were the EXPERIMENTAL group
  • 41 murderers (39 men + 2 women)
  • Mean age = 34.3 years
  • All charged with murder or manslaughter
  • All pleaded NGRI
• Methodology 4 - Control group

  • Formed by matching each murderer with a 'normal' individual with the same sex, age + IQ
  • The 6 schizophrenics were matched with 6 other schizophrenics from a mental hospital
  • Other controls had no history of psychiatric illness, nor a history of close relatives + non significant physical illness. None were taking any medication