The purpose of the study is to determine if non-invasive measurements of brain waves from the skin called electroencephalography (EEG) can predict whether the brain stimulator will help your symptoms. Our goal is to obtain these brain wave measurements with patients both awake and under general anesthesia, and then to evaluate which brain wave patterns are associated with clinical improvement to determine if they could be useful for predicting whether the surgery will work. If such predictive measures were established based upon the findings of this study, they could be used in the future to improve surgical outcomes in the following ways: (1) to help guide surgical targeting in the operating room awake or under anesthesia, (2) to guide post-operative programming in clinic, and (3) and to develop potential feedback systems for "automatic" programming of the brain stimulator system at home.

Inclusion Criteria:

1. Patients who elect to undergo deep brain stimulation as part of routine clinical care for movement disorders (Parkinson's disease, essential tremor, dystonia, Tourette's syndrome).
2. Adults, ages 19 and older

Exclusion Criteria:

1. Patients who are outside the age range for inclusion
2. Patients who are unable to consent to the research for cognitive or behavioral reasons
3. Patients who are medically too ill to participate, and
4. Patients who have their DBS programming at outside facilities

Patients who undergo deep brain stimulation as part of routine clinical care for movement disorders (Parkinson's disease, essential tremor, dystonia, Tourette's syndrome).