raine et al
Cards (14)
- quasi experiment = iv is not artificially manipulated = not guilty by reason of insanity and dv was brain activity
- opportunity sampling - was done at California uni = 41 ppts = 39 men and 2 women = urine tested to medication free for last 2 weeks
- mean age of 34.3 and matched on age, gender and schizoid or not (6 in each)
- practiced continuous performance task 10 mins before
- start CPT then 30 seconds after injected with FDG = radio active glucose
- 32 mins later pet scan is done
- pet scan produces 10mm horizontal slices of brain
- findings
- no difference in mid brain and cerebellum
- decreased activity in pre frontal cortex (impulse) corpus callosm (hemisphere communication) and left angular gyrus (iq)
- left handed murderers = more asymmetry
- performed same on cpt so no difference due to task
- no difference with race
- 23 NGRI had head injuries when younger but no impact
- conclusions
- brain is complex and violence is not down to one area but how they communicate
- NGRI have abnormal brain functioning
- brain abnormalities don't mean aggressive just more predisposed
- supports assumption certain areas of the brain link to violence
- quasi experiment = no control over IV = may be extraneous variables = lowers internal validity
- matched pairs = on age, sex, gender and schizoid or not = less ppt variables = higher internal validity
- standardised procedure = uses pet scans and step by step process = can be replicated to check for consistency = higher external reliability
- alternative evidence = banduras bobo dolls = environmental determinism = aggression is learnt not biological
- valid consent = APA approved as all consented = ethical (but are they vulnerable individuals)
- potential harm = stress and injection = NGRI would experience anyway but control group would not so unethical
- negative social implication = may assuume violence is out of control = used as excuses or to discriminate
- positive legal implications = look for alternative rehabilitation = help protect society