Objective: to deliver a responsive therapeutic stimulation to patients with Essential Tremor (ET) Background: Essential Tremor (ET) is one of the most common movement disorders defined as a rhythmical, involuntary oscillatory movement of the limbs. Intention tremor occurs in the hands and arms, typically with a slow oscillation (~5-10 Hz). It is experienced during the initiation and execution of goal-directed reaching motions, while it is absent at rest. Although the pathophysiological basis of ET remains unknown, a pathological synchronous oscillation in a neuronal network involving the thalamus, especially the ventral intermediate nucleus (Vim), the premotor (PM) and primary motor (M1) cortices, and the cerebellum has been suggested. Methods: It is assumed that deep brain stimulation (DBS) suppresses tremor by masking the “tremor cells” in the Vim. Stimulation would be delivered on demand based on the presence of specific biomarkers such as movement intention (mu rhythm on motor and premotor cortices), presence of tremor (accelerometer), coherence between electrocorticography (ECoG) and accelerometer. Results: It was possible to detect movement intention within a single trial consistently in the PM and the VIM, showing decrease in low frequency beta oscillations (high beta 18-30 Hz for PM, narrow band high beta 24-27 Hz for VIM) before movement (even in the presence of 105 Hz DBS delivered in the Vim). Conclusions: Using the biomarkers found, it will be theoretically possible to create a closed loop system for ET. This approach would allow theoretically to deliver an equally effective treatment while avoiding most of the stimulation side effects such as balance and speech impairment, and slowing the battery depletion of the implant.

Disclosure: Dr. Opri has nothing to disclose. Dr. Shute has nothing to disclose. Dr. Molina has nothing to disclose. Dr. Foote has received personal compensation for activities with Medtronic as an advisory board member. Dr. Okun has received royalty payments from Demos, Humana, Amazon, Smashwords, Books4Patients, and Cambridge. Dr. Okun has received research support from the Michael J. Fox Foundation, the National Parkinson Foundation, the Parkinson Alliance, the Smallwo Dr. Gunduz has nothing to disclose.