Raine et al 1997- classic

A-  to investigate whether brain dystfunction can predispose violence & look at brain differences between murderers who pleaded NGRI and a control group on non murderers. 

P- 41pp (39m & 2W) and 41 controls (charged w/ murder or manslaughter) 

control group matched w/ Pp at sam age/sex. av age= 31.7yrs. 

• 23 w/ a histroy of brain damage 
• 6 w/ schizophrenia 
• 2 epilepsy 
• 3 substance abuse 
• 2 affetcive disorder                  
• 2 paranoid personaltiy disorder 
• 3 hyperactivity 

All Pp were medication free 2 weeks prior to the scan 

10 minutes before injected w/ flurodeoxyglucose

contuinous performance task- 32 minutes. involved sequences of blurred numbers to focus on. 

PET scans on brain

results analysed using the cortical peel technique (slices examined for glucose values for each region compared)       &        box peel techique (2cm2 boxes of brain area examined and linked to scan results) 

R- murderes have lower glucose metabolism in prefrontal cortex, parietal lobe and corpus callosum. 

• murderes had assymetrical acitivity in hippocampus, thalamus and amygdala
• identical acitivity found in the temporal lobes.

C- violence has biological links- its a complex relationship w/ causes and no single mechanism

abnormal activity in amygdala, thalamus, hippocampus and medial temporal lobe

positives- 

• pet scans- v scientific. provides reliable comparison between pp and control group
• control group- basline comparison. easier to identify differences. 
• drug free 2 weeks before the scan- therefore meds didnt affect the results 

negatives- 

• only represent small number of violent offenders- pleading NGRI is not representative 
  
• impossible to be sure brain dysfucntion is directly linked to behaviour 
• no. of extraneous variables- could interfere with results