THE NEURAL BASES OF AGGRESSION AND RAGE IN THE CAT

This paper considers some of the basic findings underlying the neural bases of aggression and rage in the cat. The two basic models consider ed in this paper include predatory attack behavior and defensive rage. Anatomical studies point to the importance of the perifornical latera l hypothalamus for predatory attack and the medial hypothalamus and do rsal half of the midbrain periaqueductal gray for defensive rage as cr itical regions for the integration and expression of these two forms o f aggressive behavior. Other experiments point to the important role o f limbic structures in modulating each of these responses. The modulat ing properties of limbic structures provide a basis for understanding how dysfunctions of the temporal lobe can result in marked changes in aggressivity in humans. To date, studies combining brain stimulation, neuroanatomical, and neurochemical procedures have begun to identify t he likely neurotransmitters that are associated with the key pathway f rom the medial hypothalamus to the periaqueductal gray over which defe nsive rage behavior is mediated, as well as the efferent pathways of t he amygdala which modulate this form of aggression. Excitatory amino a cids that act upon NMDA receptors have been implicated as the neurotra nsmitter associated with the descending pathway from the medial hypoth alamus to the periaqueductal gray. Regions of the amygdala that facili tate defensive rage include the basal complex, which projects to the p eriaqueductal gray and utilizes excitatory amino acids as a neurotrans mitter, and the medial nucleus which projects to the medial hypothalam us and utilizes substance P as a neurotransmitter In contrast, an enke phalinergic pathway that arises from the central nucleus of amygdala a nd which projects to the periaqueductal gray has been shown to powerfu lly inhibit defensive rage behavior. (C) 1997 Elsevier Science Ltd. Al l rights reserved.