Déclenchement de réactions d'Agression interspécifique par lésion septale après lésion préalable de l'amygdale, chez le rat

Abstract

In spontaneously nonkilling rats, septal lesions induce the initiation of mouse-killing behavior whenever a prior lesion of the medial part of the amygdala was performed 3 months earlier. The lesion elicits the characteristic septal hyperreactivity, as the animals have recovered from the opposite effect of the amygdaloid lesion after that prolonged delay. The initiation of interspecific aggressive behavior by septal lesions in intact nonamygdalectomized rats depends on the degree of preoperative familiarity with the mouse. As a matter of fact, septal lesions induce by themselves very few aggressive reactions in previously nonkilling rats. The amygdaloid lesion abolishes the capacity to develop a stable inhibition of the killing behavior on the basis of repeated contacts with a mouse. These results confirm that the amygdala is involved in the development and maintenance of a specific behavioural inhibition in the nonkilling rat.