topic 1 - what makes a criminal? Flashcards
what was the aim of Raine’s study?
To look at measures of cortical and subcortical brain functioning, using PET scans in a group of murderers pleading not guilty by reason on mental insanity. (NGRI)
what did Raine expect the study to show?
The murderers would show evidence of brain dysfunction in their prefrontal cortex, as well as other areas linked to violent behaviour, such as their limbic system and corpus callosum.
He also predicted they would not show dysfunction on the areas of the brain not linked to violent behaviour.
what was the sample used in Raine’s study?
experimental group (murderers)
-41 subjects (39 men, 2 women)
-mean age of 34.3 years
-been charged with murder of manslaughter and pleaded NGRI
-6 had schizophrenia, 23 had injuries or organic brain damage, 3 had history of psychoactive substance abuse, 2 had affective disorders, 2 had epilepsy, 3 had a history of hyperactivity and learning disability, 2 had passive aggressive or paranoid personality disorders
control group:
-41 people matched by age and gender with a mean age of 31.7 years
-6 schizophrenic murderers matched with 6 schizophrenic controls
-the rest of the control group thoroughly screened and showed no history of psychiatric illness
what the procedure in Raine’s study?
10 minutes before the injection of FDG, suspects were allowed to practice the CPT task so they knew what to expect .
30 seconds before they began the CPT task, they started it
-30 second delay used to ensure the novelty of the task did not show up on the scan
after 32 minutes, the subject was transferred to the PET scanning room and their brain was scanned 10 times at 10mm intervals to measure brain activity is the cortical and subcortical regions of the brain
what were the materials used in Raine’s study?
thermoplastic head holder individually modelled
PET machine to image brain functioning
fluorodeoxyglucose (FDG)
-tracer injected to trace the metabolism of glucose by the brain
-PET scanner picks up the tracer and the concentration of glucose metabolism can be seen in different areas of the brain
high activity indicated by warm colours with highest activity showing up red
continuous performance task (CPT)
-required participants to search for on the screen and press a button to indicate when the targets were spotted
-requires concentration so should used the prefrontal cortex
what were the results of Raines study?
there was no differences in the performances of the task between the two groups, there was evidence of significant differences in brain metabolism in a number of areas.
cerebral cortex:
compared to the controls, NGRIs had:
-more activity in their occipital areas
-no difference in their temporal areas
subcortical areas:
compared to the controls, NGRIs had:
-less activity in the corpus callosum
-less activity in the left side and more activity in the right side of the amygdala and the hippocampus
-more activity in the right side of the thalamus, though no difference in the left side
reduced activity in the prefrontal areas may explain impulsive behaviour, a loss of self control, evidence of immaturity and the inability to modify behaviour.
also suggested that the limbic system (amygdala) supports theories that violence is due to unusual emotional responses such as lack of fear.
what was Palmer and Hollin’s study into moral development?
compared the moral development of:
-126 male offenders aged 13-21, recruited from a young offender institute and magistrates courts
-332 non offenders aged 13-22, recruited from schools and a university in the west midlands
self report data was collected on their socioeconomic status and two psychometric measures:
-sociomoral reflection measure short form, included 11 questions which assess moral reasoning
-self reported delinquency checklist
found that offenders had less mature moral reasoning
-most were pre conventional
non offenders were mostly in the conventional level
what was Jahoda’s study?
Ashanti tribe in Ghana believe the day you are born affects your personality.
-children are given a soul name based on the day they were born
-they also believe a boys temperament is influenced by the day of the week they were born
Jahoda examined the names of criminals who have committed violent offences recorded in court over the last 5 years
-found 22% of violent offences were committed by those with Wednesday names
-only 6.9% of violent crimes were my Monday named boys
Monday = Kwadwo = placid
Wednesday = Kwaku = violent/aggressive
what was Raine’s Mauritius study (3 part intervention)?
he used a sample of children with low resting heart rates from Mauritius and split them into two groups:
-100 children given a three part ‘intervention’ to encourage them to behave better
-a matched control group of children who had no intervention
3 part intervention programme:
1. nutrition - balanced nutritious diet provided
2. physical exercise - structure games, gym and free play
3. cognitive stimulation - a curriculum with toys, arts, crafts etc.
at age 11, the group who received the intervention showed better concentration, had more mature brains compared to controls
at age 17, they showed significantly lower levels of conduct disorder, were less cruel to others, less likely to start fights, were less hot tempered
what was Raine’s Mauritius study (omega-3 part)?
Raine gave a further 100 children omega-3 supplements once a day in the form of a juice drink for 6 months.
Compared to a group of children given juice but no omega-3.
after 12 months, parents of those children given omega-3 reported lower levels of delinquency, aggression and attention problems.
-> Raine concluded that omega-3 could reverse brain functions that predispose children to potentially become criminals
-> It increases dendritic branching, improves synaptic functioning, improves cell size and regulates neurotransmitter functioning
how does smoking during pregnancy link to crime?
smoking during pregnancy can result in higher pre natal testosterone exposure
-mothers who smoke have higher testosterone levels, so exposes the foetus to more
-experimental work in animals shows a casual connection
being exposed to high levels of testosterone in the womb is linked to higher levels of aggression, sensation seeking behaviour and impulsivity which are all associated with anti-social and violent behaviour as well as hyperactivity and a lack of empathy.
