G543 - Turning To Crime: Biology - Raine Et Al Flashcards
What type of scanning method was used?
PET scanning (positron emission tomography)
What was the aim?
To determine whether there is a biological basis for criminality
How many criminals were studied?
39 males 2 females
What were the criminals charged with?
Murder or manslaughter in california
What did they all plead?
Not guilty by reason of insanity (NGRI)
What were the 7 reasons for referral?
>Schizophrenia >head injury or organic damage >psychoactive drug abuse >affective disorder >epilepsy >hyperactivity or learning disorder >personality disorder
How many participants were in the control group?
41
What were the control group matched on?
Sex and age. 6 schizophrenics were also matched with the schizophrenics in the experimental group
What do you need to inject into the participant for PET scanning?
A tracer - flurodeoxyglucose or FDG.
What is the tracer taken up by?
The active areas of the brain. The more glucose taken up the more active the brain area is
What were participants given while having a PET scan?
A continuous performance task (CPT)
What lobes does the CPT specifically aim to activate?
The frontal lobes and the right temporal and parietal lobes.
Where did murderers have significantly reduced activity?
Both sides of the prefrontal cortex, the posterior parietal cortex and the corpus callosum
Where were there abnormal asymmetries?
Amygdala, thalamus and hippocampus
Which hemisphere had lower activity compared to the control group
The left hemisphere had lower activity than the right hemisphere in contrast with the control group
What has the Amygdala been linked to in other studies?
Violent behaviour
What is the prefrontal cortex involved in?
Regulating behaviour
What does damage to the prefrontal cortex make it more likely for a person to do?
To act out aggressive impulses
Subjects who have had their corpus callosum disconnected have an an inability to do what?
See the consequences of their actions
What could corpus callosum disconnection be mirrored by in the NGRI criminals?
Low levels of activity in the corpus callosum
How could a person be helped to avoid any possible violent behaviour in the future?
We could scan people to see if they have any of the discovered differences in brain activity levels
Why were the criminals regarded as ill rather than criminal?
The crimes committed were a result of their behaviour being influenced by their biology
