Subthalamic neuron activity related to tremor and movement in Parkinson's disease (original) (raw)

Single cell activity recorded in the subthalamic nucleus (STN) of Parkinson's patients and the effect of tremor, passive and voluntary movement upon the same cells are described. Three types of cells were distinguished by the pattern of discharge: tonic, phasic and rhythmic. They all demonstrated high mean ®ring rates (65, 59 and 69 Hz, respectively). Simultaneous recordings of muscle activity and tremor helped in de®ning cell activity. The implantation of the de®nitive stimulating electrode in the patients was based on the number of STN cells related to tremor, active and passive movements (mean = 68%) along the track chosen. Cells were related to tremor (n = 21; 11%), modi®ed the discharge with differences in the amplitude of tremor (n = 4), and changed the rate and pattern when tremor stopped spontaneously or arti®cially (n = 6). Movement-related cells (n = 97; 51%) showed a cyclic activity correlated with phases of the movement, or modi®ed the ®ring rate along the performance of the movement. Tremor and movement-related cells (n = 11; 6%) revealed an interesting sensory-motor integrative function. Patients were assessed pre-and postoperatively according to the Uni®ed Parkinson's Disease Rating Scale (UPDRS; , the core assessment program for intracerebral transplantations (CAPIT;, the Hoehn and Yahr classi®cation , and the Schwab and England scale . Motor performance was video-recorded during on±off pre-and postoperative periods.