Circadian Adaptive DBS in Essential Tremor

Deep brain stimulation (DBS) of the thalamus is an effective treatment for medically refractory essential tremor (ET). DBS involves delivering continuous stimulation to the brain through electrodes permanently implanted in the thalamus. Despite proven effectiveness, the long-term benefit of DBS can wane over time (habituation) and side effects, including paresthesia and dysarthria, often limit the amplitude of the stimulation, resulting in suboptimal control of tremor. In clinical practice, many groups advise patients to switch their devices off at night to avoid habituation and reduce side effects. However, manually turning off the device at night can result in uncontrolled tremor when the patient moves at night. This study aims to develop an algorithm that automatically turns off stimulation when a patient is asleep, based on circadian brain signals. Turning off stimulation could potentially improve the therapy by limiting adverse effects, increasing efficacy, reducing the risk of habituation, and prolonging battery life. This study will evaluate the feasibility, safety, and tolerability of circadian adaptive DBS.

Inclusion Criteria: * Diagnosis of Essential Tremor confirmed by a Movement Disorders specialist following established criteria recommended by the Movement Disorders Society * Patients implanted with unilateral or bilateral VIM DBS leads attached to the Medtronic Percept DBS device for the treatment of Essential Tremor * Patients with clinical benefit of DBS as defined by a 30% improvement on the TRS or TETRAS at least 3 months after DBS implantation * DBS programmed in a monopolar configuration allowing chronic brain sensing (C+1- or C+2- in ring mode or any direction) * Be between 21 and 89 years old * Ability to give informed consent for the study Exclusion Criteria: * Inability to comply with the study protocol * Pregnancy: all women of childbearing potential will have a negative urine pregnancy test prior to undergoing the study * Current active suicidal ideation (Yes to #2-5 on C-SSRS) * Any personality or mood symptoms that study personnel believe will interfere with study requirements