Classic study: Raine et al. (1997)

Question 1

Evaluate Raine et al.

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Answer 1

^Int reliability, ^control. Ppt matched across exprmt and ctrl groups on 3 confounding variables. Standardised procedures used to control other variables (same CPT used for 32mins). PET scans = same protocol, identical experience

PET scan = misleading results, >int validity. Scanned brain in 10mm slices relative to the canthomeatal line (imaginary line from corner of eye to middle of ear). Varies between individuals = hard to locate precisely diff brain areas under study. >accuracy

Socially sensitive. Shows how society responds to aggro crim behaviour, deals w issues of punishment. Murderers not entirely responsible for their crime as brain dysfunction

Question 2

What was Raine et al’s aim?

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Answer 2

• Use brain scanning to identify brain impairments in people charged with murder who pleaded NGRI

Question 3

What was the procedure in Raine et al’s study?

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Answer 3

• 41 murderers, 41 non-murderers (free of medication)
• Matched on sex, age and ethnicity
• Each ppt had PET scan on brain
• Injected w radioactive tracer, light up brain metabolism on scanner
• Then completed CPT, identifying targets on a screen and pressing button during 32min period after injection, encourage uptake of tracer in areas of brain researchers wished to investigate
• PET scan immediately after 32mins (took 10 images)

Question 4

What did Raine et al. find?

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Answer 4

• Murderers = sig >glucose metabolism than controls in cortical regions (prefrontal areas)
• Murderers = >metabolism in subcortical regions (left amygdala, corpus callosum, temporal lobe)

Question 5

What did Raine et al. conclude?

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Answer 5

• Interacting brain areas being impaired create a predisposition to violence when environment is ‘right’