raine et al Flashcards
what is the aim of raine
the brain of murderers who pleaded not guilty by reason of insanity were different from the brains of non murderers
what is the hypotheses of raine
individuals who showed serious violence would have dysfunction in specific areas of the brain but not in other specific areas
what is the sample of raine
matched pairs design
41 murderers pleasing not guilty by reason of insanity
average aged of 34.3 years old 39 men and 2 women
who had been charged with murder or manslaughter
23 people with history of brain damage
6 people with schizophrenia
3 with history of substance abuse
2 with an affective disorder
2 with epilepsy
3 with learning disability
2 paranoid personality disorder
what is the procedure of raine
control group matched each murderer with a normal participant of the same sex and age
clear attempt at matched pairs but could not match variables in same people so could be an independent measures design
IV = whether or not participant was a murderer
DV = measures of brain activity found by PET scans
PET SCANNING PROCEDURE =
carried out a practice test n the continuos performance task - carried out 10 mins before the fluordoxyglucose tracer was injected
- 30 seconds before the tracer was injected the continuous performance was started
- continous performance tsk chosen was one that had been shown to give an increase in glucose metabolic rates in the frontal lobe
- after 32 minutes for the FDG uptake to occur the participant was taken for a PET scan
brain regions identified by =
- cortical peel technique
- a box technique
what are the results of raine
in task carried out before PET scans there was no difference in performance
CORTICAL REGIONS -
- murderers had lower glucose metabolism to controls, specifically in the left and RIGHT MEDIAL SUPERIOR CORTEX , the LEFT ANTERIOR MEDIAL CORTEX
shows that specific brain are as showed as different activation in the murderers compared to controls
- PARIETAL LOBE - murderers had lower glucose
- TEMPORAL LOBE - no sig difference between murderers and controls
- OCCIPITAL LOBE - murderers has higher glucose metabolism than controls
- CORPUS CALLOSUM - murderers had lower glucose
- AMYGDALA - murderers has reduced activity in left amygdala and greater in right amygdala
- MEDIAL TEMPORAL LOBE - murderers has reduced left activity and greater right activity
- THALAMUS - murderers had greater right thalamic activity than controls
what is the conclusion of raine
murderers have reduced glucose metabolism in the prefrontal cortex, parietal cortex and corpus callosum
abnormal activity with regard to symmetry in the amygdala and hippocampus
SUPPORTS THE IDEA THAT VIOLENCE HAS BIOLOGICAL CAUSES AND GIVES IDEAS ABOUT SPECIFIC ISSUES THAT MIGHT LINK TO VIOLENT BEHAVIOUR. ABNORMAL ACTIVITY ASSOCIATED WITH LACK OF FEAR, LOW SELF CONTROL, INCREASED AGGRESSION AND IMPULSIVE BEHAVIOUR
strengths of raine
PET scanning was used and such scans can be interpreted objectively by more than one researcher. more reliable as it is scientific as there is objectivity and replicability
a large group was involved, sufficient people in each group for conclusions to be firm and may have bee generalisable to other murderers pleading not guilty
weaknesses of raine
can only be generalised to murderers pleading not guilty as that was the specific group identified , can not be said to be true of all violent offenders
reason for the brain dysfunctions cannot be explained y the study the findings describe the difference but do not explain them. could be genetic or from the environment
