Classic Study: Raine et al.: Flashcards
What was the Aim of Raine?
To see if murders pleading NGRI would show dysfunction in area of the brain associated with violence such as the pre-frontal cortex, amygdala.
Who were the experimental group?
41 murderers (39m, 2f) pleading NGRI due to reasons such as SZ, brain injury, substance abuse. They had a mean age of 31.3 years.
Who were the control group?
41 people (39m, 2f) who where matched with the E group according to age, gender, diagnosis of SZ. Their mean age of 31.7.
What was the procedure of Raine?
Ppts were screened for gen mental health. None of ppts were taking medication prior to the brain scan (2 weeks). Consented to take part. Ppts worked on a continuous performance task (CPT) focusing on presentation of blurred no. 10 min trial. Injected with radioactive tracer for 32 mins. After PET scan.
What were the results of Raine?
In the cortical areas, the NGRI’s scans showed: Lower glucose metabolism in pre-frontal than control, lower glucose metabolism in parietal areas than control. In the Subcortical areas: Lower G M in the corpus callosum, asymmetrical G M in the amygdala with lower activity in the left and higher in right. No difference in how well they did in the task, ID didn’t affect.
What was the conclusion of Raine?
Deficits in functioning of Pre-Frontal (impulsive), with different areas of the limbic system could explain why violent criminals are unable to learn from the consequences of their actions. Amygdala= don’t react correctly to social situations.
One strength: Standardised:
A strength of Raine’s study using PET scans of the NGRI’s compared to controls is that brain activity is assessed in a standardised way. This is a strength as it allows for the procedure to be replicated to assess the impact of dysfunction with violence.
One weakness: Ecological Validity:
A weakness of Raine’s used the CPT task which is artificial and unrealistic of aggression. Therefore, is has low ecological validity when assessing the brain activity in the NGRI and control group is not a real representation of how the brain works when committing murder.
Overall conclusion of Raine:
Useful: Raine’s study is useful because it found that murders had lower brain functioning in areas like the prefrontal cortex which means practical applications can be created such as using brain scans to predict and monitor those most at risk of crime.
Not Useful: This study is not useful as he could be making assumptions as it doesn’t account for other factors as we don’t know if violence is caused by brain activity which means the results are less valuable as it can’t accurately predict if brain damage causes crime.
