Chronic post-coma consciousness impairment is a severe handicap. Preliminary studies suggest that deep brain stimulation of the thalamic-tegmental reticular system could improve consciousness disorders, and facilitate the emergence of conscious behavior. The aim of this protocol is to study the effects of deep brain stimulation on conscious behavior, using a patient-based anatomic mapping for stereotactic surgery, and the Coma Recovery Scale-Revised (CRS-R) as clinical assessment criterion.