These two states of comatose-ness have two very different odds of recovery. Today, Deep Brain Stimulation (DBS) is used in a variety of other neurological diseases and conditions, including in patients who are in a VS and in a MCS. In a study conducted at the Nihon University School of Medicine in Japan, Doctor Yamamoto conducted a study involving DBS and its affects on VS and MCS. DBS was first introduced in 1987 when doctors implanted electrodes into patients who had Parkinson disease (Chen 200-212). This procedure amplifies the activity in the brain by activating the synapses and allowing them to communicate more efficiently (Chen 200-212). DBS also increases the cerebral blood flow which then stimulates neurogenesis, the process in which impaired parts of the brain regenerate resulting in the repairment of the damage tissue (Chen 200-212). The electrodes provide a small current that aids in the lessening of the tremors the patients were experiencing due to their condition (Chen 200-212). DBS thus gives patients the potential to awaken, effectively pulling them out of their comatose