Studies into abnormal aggression in humans and rodents: Methodological and translational aspects

- Abnormal aggression is defined in terms of rule breaking by, and functionality for the perpetrator.
- Human approaches include “aggression-history” and “manifest-aggression” studies.
- Aggression-history studies reveal mechanisms underlying “psychological landscapes” associated with aggression.
- Manifest-aggression studies are linked to executory mechanisms.
- Rodent models of abnormal aggressionare translationally relevant for human manifest-aggression studies.

Here we review the principles based on which aggression is rendered abnormal in humans and laboratory rodents, and comparatively overview the main methodological approaches based on which this behavior is studied in the two categories of subjects. It appears that the discriminating property of abnormal aggression is rule breaking, which renders aggression dysfunctional from the point of view of the perpetrator. We show that rodent models of abnormal aggression were created by the translation of human conditions into rodent equivalents, and discuss how findings obtained with such models may be “translated back” to human conditions when the mechanisms underlying aggression and its possibilities of treatment are investigated. We suggest that the complementary nature of human and rodent research approaches invite a more intense cross-talk between the two sides of aggression research than the one presently observed.