Biological - Classic Evidence : Raine Flashcards
Methodology
> quasi-experiment with matched pairs design.
IV = NGRI or not. DV= brain differences
Methodology - participants
Experimental group = murderers pleaded NGRI
>41 - 39M, 2W
> mean age - 34.3 years
>refered to Uni of California - had some form of mental impairment
>schizophrenia, head injury, drug abuse, affecive disorder, epilepsy, hyperactivity/learning, personality disorder
> medication free
CONTROL GROUP
matching with normal indiv same sex,age
>6 schizophrenics matched
Procedures
> sample obtained using oppotunity sampling
PET scan used to study the active brain
given injection of a tracer (FDG) - taken up by active areas = possible to compare brains
asked to do continuous performance task - aimed to activate target areas to see how they functioned
1. chance to practise CPT before FDG
2. 30s before FDG, started CPT
3. 32m after FDG, PET done. 10 horizontal slices of brain recorded - article provides precise details = replicated
Findings - brain differences
Reduces activity in NGRI in areas prev linked violence:
Increased in NGRI areas not prev linked violence
No diff between NGRI, control - areas not prev violence
Findings - performance on CPT
both performed similarly
therefore - observed brain diff not related
Findings - other differences no controlled for
> Handedness - 6NGRI left = less amygdala asymmetry _ higher medial prefrontal activity
Ethnicity - 14 non-white -no diff
Head injury - 23 - no diff
Conclusions
> study supports past research - links between areas of brain and aggression.
thf - evidence NGRI have diff brain functioning
However - neural processes= complex can’t be reduces to single brain mechanism
Conclusions - confounding variables
> carefullry designed - involving large sample and matched controls
head injury and IQ have not been ruled out as contributory factors
Evaluate methodology - strength
P - highly scientific = strength
E - used PET scans to investigate brain diff, FDG, eamine brain in action
E- modern scientific instruments - provide trusted evidence
L - reliable
Evaluate procedures - weakness
P - criminals not studied, only murderers.
E -Doesn’t give insight to criminals in general = conclusions restricted to specific group
E - weakness - murder not most common, more common = more benefitial
P - control groups used
E- schizophrenics weren’t paired, nor other conditions
E - could’ve affected conclusions
Evaluate Methodology - cause and effect relationship
P - not possible to fully state a cause-and-effect relationship
E - findings don’t show violence duo to biology alone, Other factors e.g upbringing must influence
E- some NGRI may had home environment that accepted violence, peer group that encouaged it = social influence
L - further research about home life
Evaluating Procedures
P - strict procedures
E - NGRI matched with a control, not on medication, same CPT taske + PET used
E - easier to determine cause-and-effect relationship between variables
L - findings can be replicated, reliability can be checked for consistency = valued and treusted research.
Evaluated ethical - consent
P - valid consent not given
E - as pleaded NGRI = not mentally competent to fully understand, aware of rights during process. procedures - CPT could’ve caused distress = risk of psychological harm
Evaluate ethical - social implications
conclusions could lead to courts using biological evidence against innocent people with similar brain abnormalities - imprisoned
Take away free will
conclude murderers are born not made