We present a 62 years old man with Parkinson's disease (PD) who underwent bilateral stimulation in the subthalamic nucleus (STN). During the intraoperative evaluation, stimulation through the lowest contact in the right STN area, induced an acute depressive state, during which the patient was crying and expressing that he did not want to live. The patient returned to his normal state of mood within seconds after the cessation of stimulation. Repeated blinded stimulations resulted in the same response. Immediate postoperative magnetic resonance imaging (MRI) revealed that the lowest contact of the right electrode was located in the substantia nigra.