Hypothalamic influence on performance of midbrain-induced switch-off behavior in cats

Experiments were carried out to study the effects of electrical stimulation of the hypothalamus on the performance of switch-off behavior motivated by electrical stimulation of the midbrain central gray. Stimulation of the medial hypothalamus paired with central gray stimulation facilitated the performance, resulting in a decrease in response time. Stimulation of the lateral hypothalamus except the midlateral portion inhibited the performance, thus increasing the response time. Stimulation of the midlateral hypothalamus facilitated the performance. It appears that stimulation of the medial hypothalamus enhances the motivation induced by central gray stimulation, and that stimulation of the lateral hypothalamus inhibits the performance with the induction of a different motivation. Midlateral stimulation facilitates the performance probably by elicited go-mechanism.