Classic research

• What is the classic research of the biological approach?

  Raine

  Brain abnormalities in murderers indicated by positron emission tomography
• Aims of Raine’s research 


  Look at direct measures of both cortical and subcortical brain functioning using PET scans in a group of murderers who have pleaded not guilty by reason of insanity.
• Raine‘s methodology

  Matched pairs - age, sex, mental health disorders (SZ)

  Quasi study
• Raine’s participants

  Experimental group:

  41 participants

  34.3 average age

  Charged with manslaughter or murder & pleading NGRI

  Control group:

  Average age 31.7
• Procedures

  Opportunity sampling used.

  Radioactive tracer injected into participants and taken up by brain for 32 mins. During this period, each participant completed a continuous performance task based around target recognition. CPT started 30s before injection.

  PET scan.

  10 horizontal slides of brain taken.

  NGRIs level of activity (glucose metabolism) compared to controls.

  14 selected areas looked at.
• Raine‘s findings - prefrontal 


  Lower glucose metabolism relative to controls.
• Raine’s findings - parietal

  Lower glucose metabolism compared to controls.
• Raine’s findings - Temporal

  Glucose metabolism identical to controls.
• Raine’s findings - occipital

  Higher glucose metabolism compared to controls.
• Raine’s findings - corpus collosum

  Bilaterally lower glucose metabolism compared to controls.
• Raine’s findings - amygdala

  Reduced activity in the left amygdala.

  Greater activity in right amygdala.

  Compared to controls.
• Raine’s findings - medial temporal lobe 


  Reduced activity in left medial temporal lobe.

  Greater activity in the right medial temporal lobe.

  Compared to controls.
• Raine’s findings - thalamus

  Greater activity in right thalamus compared to controls.
• Raine’s findings - cingulate

  No difference
• Raine’s conclusions

  Murders pleading NGRI have statistically significant differences in glucose metabolism in selected brain regions compared to normal controls.
• Evaluation of Raine - quasi study


  Strength - IV naturally occurring - allows study of something that cannot be manipulated.

  Weakness - Less control (eg don’t know full history of participants).
• Evaluation of Raine - PET scan


  Strength - allowed active brain to be examined.

  Weakness - use of radioactive tracer makes it difficult to replicate with same participants.
• Evaluation of Raine - matched pairs

  Strength - allows for some control of participant variables.

  Weakness - weren’t matched on everything.
• Evaluation of Raine - sample 


  Weaknesses -

  Not representative of all violent crime.

  Lack population validity (all tried in state of California).
• Evaluation of Raine - conclusions

  Findings show correlation not causation.
• Ethical issues of Raine

  Consent - NGRI - not able to give fully informed consent?

  Right to withdraw - may have felt this would go against their case?

  Harm - being told they had an ’abnormal‘ brain could harm self esteem. Kept from medication for 2 weeks.
• Social implications of Raine 


  Strengths -

  Could be used to support cases in court - use brain imaging to help with verdict.

  Prevention strategies can be put in place.

  Rehabilitation.

  Weaknesses -

  Create stigma surrounding specific brain types.

  Self-fulfilling prophecy?

  Deterministic -> removal of responsibility.