A deep brain stimulator (DBS) device is like a pacemaker for the heart, but the electrodes are placed into the brain. DBS helps in neurological disorders by changing the activity of brain cells depending on where the electrodes are placed. In 1973, Yoshio Hosobuchi first performed chronic deep brain stimulation, to treat pain, by implanting electrodes. In 2002, long - term results of pallidal stimulation were reported for Parkinson's disease. Thus, this book discusses how Parkinson's disease, essential tremor, dystonia, and a few other neurological and psychiatric disorders are treated with DBS