Amygdala lesions and CER learning: Long term effect of kindling

Abstract

Six days following the electrolytic destruction of one amygdaloid complex, the remaining intact amygdala was electrically stimulated daily to develop a kindled epileptic focus. Once kindling was completed, animals were given a 2-week rest period principally to allow for the dissipation of the spontaneous interictal discharge which develops during the kindling process. When required to learn a conditioned emotional response (CER) following the rest period these animals were greatly impaired, performing indistinguishable from animals with bilateral amygdala lesions. Animals with unilateral lesions and without a contralaterally kindled focus acquired the CER at a similar rate to normal animals. Several hypotheses were entertained to account for this long term prograde effect of a kindled amygdala focus upon CER acquisition.