Electrophysiological indices of the violence inhibition mechanism and their associations with physical agression, callous-unemotional traits, and dietary omega-3
Each year, aggressive behaviour contributes to a substantial number of criminal offenses - resulting in severe personal, social, and financial ramifications. As such, there is importance for understanding the underlying mechanisms of aggression and how it might best be managed. The violence inhibition mechanism, thought to be dysfunctional in individuals characterised by aggressive behaviour and associated callous-unemotional traits, is used to explain how the perception of facial distress might inhibit an ongoing aggressive act. Despite a sizeable literature characterising the violence inhibition mechanism, to date, empirical research has overlooked this investigation on an electrophysiological level. This thesis developed a novel facial-affect stopping task in order to tease apart the distinct stages of face processing and distress-induced motor extinction using electroencephalography. Results suggested that whilst callous-unemotional traits, specifically uncaring traits, were associated with electrophysiological indices of structural/featural face processing (N170, P200), aggressive traits, specifically physical aggression, were associated with electrophysiological indices of distressinduced motor extinction (stop-N200, stop-P300). Furthermore, in light of a growing literature suggesting a benefit of omega-3 dietary intake for both aggressive and callous-unemotional traits, correlational analysis suggested an association between omega-3 and physical aggression/distress-induced motor extinction, but not callous-unemotional traits/face processing. These results have theoretical implications for understanding and investigating the violence inhibition mechanism on an electrophysiological level, as well as practical utility for better understanding how omega-3 might benefit aggressive traits and motor extinction. Specifically, the importance of distinguishing between both [1] aggressive and callous-unemotional traits and [2] face processing and motor extinction ability, when investigating the violence inhibition mechanism
