[Role of thalamic nuclei in the hypertonia and tremor of Parkinson disease].

Intraoperative recordings allowed the ventralis intermedius nucleus (Vim) to be distinguished from the ventrolateral nucleus (VL). Characteristics of the Vim include marked spontaneous activity, bursts synchronous with tremor, response of certain cells to contralateral kinesthetic and peripheral electric stimuli and paresthesia provoked by an intraoperative stimulus. Coagulation of Vim abolishes tremor while coagulation of VL abolishes hypertonus.