Hypothalamically induced intraspecific aggressive behaviour in the rat

Abstract

Summary.The effects of electrical stimulation of the lateral hypothalamus (LH) of rats on intraspecific aggressive behaviour were studied. In order to investigate the specificity of the stimulation effects, each experimental animal was stimulated in a number of different social situations.Stimulation of the LH in the presence of a subordinate male increased the amount of time spent on aggressive behaviour patterns and locomotion. In the presence of a dominant male, however, the stimulated animal never initiated a fight, whereas in the presence of an estrous female attack occurred in some rare occasions and sexual behaviour disappeared almost entirely. Stimulation of some sites also elicited mouse killing behaviour. Many of the electrodes that elicited intraspeciflc aggressive behaviour also supported intracranial self-stimulation.It is concluded that 1. electrical stimulation of this area of the LH predominantly potentiates intraspecific aggressive behaviour, 2. that this behaviour becomes overt depends on the external situation, including the behaviour of the opponent. Key words: Intraspecific aggression -Lateral hypothalamus -Electrical stimulation -Specificity -RatA number of experiments have demonstrated that in rats aggressive behaviour can be influenced by stimulating the brain electrically, by hormones, or by lesions. However, an integration of these data with ethological studies on aggressive behaviour of rats is seriously hampered, because both approaches often deal with different types of aggressive behaviour. For example in the brain-behaviour studies, predatory aggression (mouse killing) has been studied extensively by Karli (1971), whereas Brady and Nauta (1955) and Edwards and Adams (1974) analysed pain induced aggression, and Miczek et al. (1974) used food competition as a model for aggression. These types of aggressive behaviour are not identical in behavioural repertoire, sequential structure and

Aggression and Serotonin. Contribution of Inhibitory Mechanisms.

“…* Compared with the correspondent group injected saline into DRN+MRN + Compared with the correspondent group injected 5 ,7-DHT into DRN+MRN Previous electrical stimulation studies have shown that the LHA is involved in aggressive behavior including muricide [5,9,15]. In the present study, the depression of serotonergic innervation in the LHA by 5,7-DHT and the reinnervation of serotonergic fibers in the LHA by raphe transplant directly demonstrate the serotonergic inhibitory role in the hypothalamic aggressive area.…”

Aggressive behavior induced by electrical stimulation in the midbrain central gray of male rats

“…We stimulate at the same hypothalamic site as Koolhaas [1978], although the test situation is slightly different. The wound pattern is puzzling.…”

Delineation of Violence from Functional Aggression in Mice: An Ethological Approach

“…The earliest lab-based experiments focused on violent 'rage' behaviors in cats following neuro-physiological manipulations in the brain (Bard 1929;Kaada 1966). Several rodent models of violence were developed using lesions to pre-frontal cortical areas, models of Alzheimer's disease, epilepsy and electric shock models as summarized by Haller and Kruk (2006).…”