Stimulation of lateral hypothalamus during sickness attenuates learned flavor aversions

Abstract

After rats consumed a flavored substance and were made sick, the experimental animals pressed a lever for 15–20 min to obtain electrical stimulation of the lateral hypothalamus (LH). Although symptoms of sickness were apparent for at least an hour after the stimulation period ended, these rats subsequently drank substantially more of the substance that had been paired with sickness than did control rats that were otherwise similarly treated but not stimulated. When the period of stimulation was interpolated between consumption and sickness, the subsequent consumption of the flavored substance did not differ in stimulated and unstimulated rats. Thus, LH stimulation attenuated the learned flavor aversions by modifying the sickness experience.