Electrophysiological methods are used preoperatively here on patients with Parkinson’s disease, to delimit the surgical target during implantation of chronic stimulation electrodes in the Vim (Ventralis Intermedius) in the case of tremors, or in the Subthalamic nucleus (STN) in the case of akinesia and rigidity. These electrodes have been developed in conjunction with the team led by Professor Benabid (Grenoble hospital) and enable the exploration zone to be stimulated in a single insertion. They are implanted side by side in the target area through guiding tubes using a stereotactic procedure.