DBS is a therapy that was originally developed for the treatment of tremor in patients with Parkinson’s disease or essential tremor. DBS is considered a less invasive alternative to lesion therapy. Instead of irreversible lesions, electrical stimulation is used to affect brain activity in specific regions that are abnormal in patients with movement disorders allowing the brain to function more normally. DBS is now being used as an effective therapeutic tool for a variety of movement disorders including dystonia. DBS is not a cure, but it can markedly reduce the symptoms of some types of dystonia. With DBS, a tailored electrical stimulus is delivered through a thin wire or electrode, which is implanted deep in the brain. DBS electrodes have four metal contacts and when used for the treatment of dystonia are implanted in an area of the brain known as the basal ganglia. The electrical impulses are generated by an internal pulse generator (IPG—also sometimes called a stimulator) which provides the electrical current that is passed through the electrode implanted in the basal ganglia. The IPG functions as a pacemaker and is implanted under the skin in the chest usually just below the clavicle. This device is connected to the electrodes in the brain by wires that are hidden under the skin in the neck. The IPG can send electrical current through any one or a combination of the four metal contacts that are located on the electrode implanted in the brain and the rate, voltage, and duration of each pulse of electrical current can be adjusted.

How these electrical impulses improve the dystonic symptoms has been debated. The vast majority of scientists now believe that DBS interrupts the abnormal electrical activity in the basal ganglia believed to result in dystonic movements and allows the brain to function more normally.