AO3

• The amygdala's role is supported by Pardini et al (2014)

  • carried out a longitudinal study of male violence from childhood to adulthood. Some of the 56 participants with different histories of violence had brain MRI scans at age 26. The results showed that participants with lower amygdala volumes had higher levels of aggression and violence. This difference remained even after confounding variables were controlled.
  • This suggest that amygdala plays and important role in evaluating emotional importance
• The role of the hippocampus in aggression is supported by MRI scans of hippocampal asymmetry:

  • Raine (2004) provided support for the role of the hippocampus in aggression. He compared two groups of violent criminals. One group were called unsuccessful psychopaths as they had been caught and the other group were classified as successful psychopaths as they had not been caught. Raine found that unsuccessful psychopaths has asymmetry (different sized hemispheres) of the hippocampus
  • This may impair how the hippocampus and amygdala work together leading to inappropriate verbal and physical responses
• Evidence for serotonin and link with aggression

  • Drugs that increase serotonin levels also reduce levels of aggression. In support Carracco and Kavoussi found that by giving antidepressant Prozac to individuals then aggression was reduced.
  • This suggests that low level serotonin could be a casual factor in aggression.
• CB to the support of serotonin

  • not all people with low levels of serotonin display aggressive behaviour. Booji (2010) did longitudinal study, children with low serotonin were more aggressive yet when they became adults they still had low levels of Serotonin but had been socialised and displayed similar aggressive levels to the normal population, except if they had been mistreated in childhood. Gene-environment interaction.
  • Diathesis - stress
• This study is backed up by Van Goozen (1997) who conducted a natural experiment on transgender sex-change patients.

  • Findings revealed testosterone levels governed aggression. Males receiving testosterone suppressants became less aggressive. Females receiving testosterone became more aggressive.