Turning To Crime - Biology Flashcards
Participants in Raines study
41 individuals charged with murder
39 men + 2 women
Referred to University of California for confirmation of insanity
Matched by age and sex to volunteers
What were Raines participants injected with?
Glucose tracer
What task did Raines participants complete and how long for?
Completed continuous performance task which measure target recognition accuracy and was designed to active specific areas of the brain
Monitored for 32 minutes then given PET scan
Raine found reduced glucose activity in what areas of the brain, and what are these linked to?
Pre frontal cortex and corpus callosum
Known to be involved in regulation of aggressive behaviour
Raine found abnormal asymmetries of activity where in the brain?
Amygdala, thymus and hippocampus
Left side lower than normal activity, right side higher than normal activity
In Raines study, the areas of the brain studied are associated with what types of behaviour?
Impulsivity Immaturity Altered emotion Loss of self control Inability to modify behaviour Aggressive behaviour
What did Raine conclude from his study?
- There is evidence to suggest murderers have significantly different patterns of activity in brain compared to non murderers
- These differences are linked to behaviours that may predispose an individual towards violence
- There are many neural processes which underlie violent behaviour - not a single factor can be blamed
What was the aim of Brunners study?
To explain the behaviour of a large family in the Netherlands where the males are affected by a syndrome of borderline mental retardation and abnormal violent behaviour (including impulse aggression, arson and attempted rape)
Participants in Brunners study
5 affected males from a family in Netherlands
How was data collected in Raines study?
Urine samples and IQ tests
What were the results from Brunners study?
- lack of enzyme MAOA
- involved in serotonin metabolism
- serotonin involved in regulation of anger and aggression
- likely to be responsible for behaviour
What did Brunner conclude from his study?
- gene mutations can be responsible for aggressive beach our which could lead to criminality
- gene mutation linked to deficit in MAOA, leading to impaired serotonin metabolism
- likely to be responsible for mental retardation in family and violent behaviour
What is status competition?
In most male species, male reproductive success is based on competition for a mate, through display and/or fighting for territory and status with other males
- males are more violent than females has they have inherited these traits
What is young male syndrome?
A characteristic combination of behaviours, such a competitiveness, risk taking and aggression in young men that makes them more likely than females to be involved in fights. They see competition amongst males and have to gain status to enable them to compete against other males.
What was the aim of Wilson and Dalys study?
To examine age and gender patterns in crimes of violence
What was the method used in Wilson and Dalys study?
Analysis of police crime records in Detroit in 1972. Age and sex of perpetrators and vitrines analysed.
In Wilson and Daly, how were the homicidal crimes categorised?
Social conflict
Crime specific
Unknown
What were the results of Wilson and Daly?
- homicides mainly committed by young, unmarried men
- most homicides concerned social conflict such as retaliation, showing off and jealousy
- fights most likely to occur when there is potential ‘loss of face’
- most victims were young unmarried males
What were conclusions from Wilson and Dalys study?
- the fact that most crimes concerned social conflict (such as retaliation, showing off, jealousy) and that most perpetrators and victims were young unmarried men could be explained by status competition
- findings supported evolutionary explanation for higher levels of crime in males than females
Aim of Raines study
To discover using PET scans, whether there are brain abnormalities in murderers who please NGRI
