PET scans to study whether the brains of violent murderers were different to the brains of non-murderers. 41 convicted murderers were studied. A control group of non-murderers was matched for sex and age.
They found a significant difference in activity levels in man brain areas between the murders and non-murderers. The murderers' brain showed much less activity in the frontal cortex, the amygdala the thalamus and the hippocampus.
The areas identified as having abnormal activity