[Stereotypical behavior developing after electric stimulation of the substantia nigra in cats].

A weak unilateral electrical stimulation of pars compacta of substantia nigra in cats provokes a stereotype behaviour, by its pattern resembling stereotypy induced by amphetamine. During poststimulatory stereotypy, there is a weakening of the arrest reaction induced by low-frequency stimulation of the caudate nucleus. Low doses of haloperidol which do not disturb the spontaneous behaviour, readily weaken trace nigral stereotypy. Such a response may be due to enhancement of nigro-striate dopaminergic transmission and the subsequent limitation of the caudate nucleus restraining function.