Functional Brain Network Changes in Patients Undergoing Deep Brain Stimulation for Essential Tremor

Summary

The purpose of this study is to collect electrophysiological data related to functional brain network changes in patients undergoing deep brain stimulation for the treatment of essential tremor. Participants will either 1) have electroencephalography (EEG) scalp electrodes placed, or 2) remain seated with their head inside of a magnetoencephalography (MEG) recording system, as resting-state and task-related data are acquired. Spontaneous electrophysiological activity will be recorded in both the eyes open and eyes closed conditions with the participant seated comfortably. These recordings will be repeated in the DBS OFF and DBS ON states, with the ON state involving specific settings identified as optimal, sub-optimal, or ineffective at achieving tremor control. They will also be repeated following the optional administration non-DBS tremor mitigation techniques, which may include one or more of the following: 1) cooling the limb, 2) oral administration of alprazolam, 3) oral consumption of ethanol (alcohol), or 4) peripheral nerve stimulation.

Conditions

• Essential Tremor

Interventions

DRUG

Alcohol

Alcohol consumption is shown to reduce tremor in individuals with essential tremor. The alcoholic beverage will be dispensed by the a clinician study investigator, and the participant will be administered the alcoholic beverage until their tremor is decreased, as determined by the clinician. Individual sensitivity to the tremor-mitigating effects of alcohol varies, but it is anticipated that only light (1-2 40% ABV drinks, containing 1-2 units of absolute alcohol \[10 mL. or 8 g of pure ethanol\]) consumption will be necessary. Participants will then repeat motor task and data collection while the alcohol is effective at controlling tremor, beginning approximately 15-20 minutes after consumption.

DRUG

Alprazolam

Alprazolam is shown to reduce tremor in individuals with essential tremor. The primary investigator will select the appropriate dose for the patient (0.5mg for patients with a body weight of up to 75kg, and 0.75mg for participants with a body weight of 75kg and higher). Participants will swallow the drug with a glass of water in the presence of the research team. If participants have not reached a sufficient level of tremor improvement, a subsequent dose of up to a total of 1.0mg of alprazolam per participant will be requested. Participants will then repeat motor task and data collection.

DEVICE

Cold Therapy

One or both of the participant's upper limbs will be wrapped with pre-chilled ice packs or a cold water circulating device such as a cryomanchet (e.g., the Breg PolarCare Glacier), and the skin temperature monitored until it lowers to 15-25°C. Participants will then repeat motor task and data collection while the limb is cool.

PROCEDURE

Peripheral Nerve Stimulation

Electrical stimulation will be applied using techniques similar to those applied during standard somatosensory evoked potential testing. Specifically, adhesive surface electrodes will be placed above the median and radial nerves at the wrist. Stimulation paradigms will be tailored to each participant based on the frequency characteristics of their tremor. Participants will receive between 20-60 minutes of stimulation, then will repeat motor task and data collection. Transcutaneous peripheral nerve stimulation may help mitigate tremor, with effects lasting beyond cessation of stimulation1-3.

Sponsors & Collaborators

• The Cleveland Clinic

  lead OTHER

Principal Investigators

• James Liao, MD · The Cleveland Clinic

Eligibility

Min Age

30 Years

Max Age

80 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2024-03-25

Primary Completion

2028-12-31

Completion

2028-12-31

Countries

• United States

Study Locations