On some clinical implications of the ventral striatum and the extended amygdala - Investigations of aggression

In this paper, we have first reviewed the animal studies which suggest an association between the amygdala and aggressive behavior, This is followed by a review of the literature of aggression in epilepsy, emphasizing the less controversial peri-ictal aggressions, with the more controversial assertion that temporal lobe epilepsy in particular is associated with an increase in interictal aggression. We then go on to describe the results of some investigations using the MRI to examine amygdala pathology in a group of patients presenting with affective aggression in comparison with a control group. The main findings are that the patients with aggression tend to have lower IQs and more psychopathology than the control group. There is no difference in amygdala T2 and volumetric assessments between the groups, but a subgroup of patients are defined with aggression, left-sided amygdala atrophy, and a history of encephalitis.