Impact of Sensory Electrical Stimulation on Sensation and Tremor

Effects of Afferent-specific Peripheral Electrical Stimulation (asES) on Sensorimotor Control and Tremor

The purpose of this study is to understand the acute, short-term and long-term impact of transcutaneous and/or percutaneous electrical stimulation with afferent-specific electrical stimulation (asES) on proprioception and fine motor control in the upper extremity. For this purpose, the researchers will use transcutaneous and/or percutaneous asES, high-density electromyography (HD-EMG), arm kinematic measurements, and standardized clinical assessments. This study will be conducted in healthy able-bodied individuals and patients with essential tremor (ET).

Study Overview

• Status: Active, not recruiting
• Conditions: Essential Tremor; Healthy Individuals
• Intervention / Treatment: Device: Continuous stimulation strategy; Device: Closed-loop stimulation strategy

Detailed Description

The purpose of this study is to evaluate the impact of afferent-specific electrical stimulation (asES), delivered either transcutaneous or percutaneous electrodes, on proprioception and fine motor control. The researchers will study the effect of asES in force perception, joint position perception, and touch sensitivity as proxies for proprioception. The researchers will also study the effect of asES on fine motor control by investigating the change in neural drive to the muscles before and after asES using the motor unit spike trains extracted from HD-EMG recordings. Furthermore, the researchers will also study the difference in effects of transcutaneous versus percutaneous asES on proprioception, fine motor control, and tremor in ET through HD-EMG and standard clinical measurements such as TETRAS and Perdue pegboard test. These results will help the researchers understand the acute, short-term, and long-term effects of various methods of asES delivery (transcutaneous or percutaneous) and their impact on proprioception and fine motor control.

Aim 1: Investigate the acute, short-term, and long-term effects of transcutaneous asES on proprioception and fine motor control. The overall goal of this study is to provide insight into the effect of transcutaneous stimulation of la afferent pathways targeted to modulate spinal reflexes in patients with ET to reduce tremors, which consequently might cause disruption in proprioception leading to changes in performance of fine motor control. The researchers hypothesize that asES might disrupt proprioception causing decreased performance in fine motor control tasks in the acute (during stimulation), and short-term (e.g., immediately following stimulation to 30 minutes post) but the effects will diminish in the long-term (up to 24 hours post stimulation) time periods.

Aim 2: Investigate the acute, short-term, and long-term effects of percutaneous asES on proprioception and fine motor control. The goal of this aim is to evaluate the effects of percutaneous asES to modulate Ia afferents and spinal reflexes to result in tremor reduction in ET, which consequently might cause disruption in proprioception leading to changes in performance of fine motor control. The researchers hypothesize that percutaneous asES will disrupt proprioception and fine motor control, but will also result in tremor reduction in the acute, short-term and long-term periods.

• Study Type: Interventional
• Enrollment (Estimated): 40
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Illinois
    • Chicago, Illinois, United States, 60611
      • Shirley Ryan AbilityLab

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria for Healthy Participants:

• Age from 18 to 80 years, inclusive
• No history of a brain and/or skull lesion
• Normal hearing and (corrected) vision
• Able to understand and give informed consent
• No neurological disorders
• No tremor
• Able to understand and speak English

Exclusion Criteria for Healthy Participants:

• History of significant head trauma (i.e., extended loss of consciousness, neurological damage)
• Known structural brain lesion
• Prior neurosurgical procedures
• Tremors (as determined by study team)
• Co-existence of other neurological diseases
• Parkinsonism
• Medical (e.g., cardiological, renal, hepatic, oncological) or psychiatric disease that would interfere with study procedures
• Pathology that could cause abnormal movements of extremities (e.g., epilepsy, stroke, marked arthritis, etc.)
• Inability to perform study tasks or assessments (e.g., follow instructions to stay still during asES procedures) or unable/unwilling to complete study forms
• Non-prescribed drug use or recreational marijuana use
• History of current substance abuse (exception: current nicotine use is allowed)
• Pregnancy
• Prisoners

Inclusion Criteria for ET Patients:

• Age from 18 to 80 years, inclusive
• No prior history of skull lesions or craniotomy
• Normal hearing and (corrected) vision
• Able to understand and give informed consent
• Diagnosis of ET (Tremor Research investigation Group criteria) by a physician
• At least moderate-severe tremor (based on the TETRAS Tremor Rating Scale) in an upper limb with pure flexion-extension wrist tremor during posture
• Stable medication doses for at least 30 days prior to study enrollment and during entire study period
• Able to understand and speak English

Exclusion Criteria for ET Patients:

• History of significant head trauma (i.e., extended loss of consciousness, neurological damage)
• Known structural brain lesion
• Prior neurosurgical procedures
• Mixed or complex tremors (as determined by study team)
• Co-existence of other neurological diseases
• Parkinsonism
• Medical (e.g., cardiological, renal, hepatic, oncological) or psychiatric disease that would - interfere with study procedures
• Pathology that could cause abnormal movements of extremities (e.g., epilepsy, stroke, marked arthritis, etc.)
• Inability to perform the study tasks or assessments (e.g., follow instructions to stay still during asES procedures) or unable/unwilling to complete study forms
• Non-prescribed drug use or recreational marijuana use
• History of current substance abuse (exception: current nicotine use is allowed)
• Pregnancy
• Prisoners

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Transcutaneous asES; Participants will be administered transcutaneous afferent-specific electrical stimulation in the upper limb using conductive pads targeting the median and radial nerves at the wrist	Device: Continuous stimulation strategy; Participants will be administered stimulation with a constant frequency stimulation.; Device: Closed-loop stimulation strategy; Participants will be administered with an activity-dependent stimulation.
Experimental: Percutaneous asES; Participants will be administered percutaneous afferent-specific electrical stimulation in the upper limb using intramuscular leads targeting the flexor and extensor muscles of the wrist	Device: Continuous stimulation strategy; Participants will be administered stimulation with a constant frequency stimulation.; Device: Closed-loop stimulation strategy; Participants will be administered with an activity-dependent stimulation.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Force perception via force matching tasks	Force perception will be measured by evaluating the participant's ability to match a target force.	Assessment will be performed before, immediately after, and 30 minutes following the administration of the intervention in a single visit
Position perception via position matching tasks	Position perception will be measured by evaluating the participant's ability to match a target joint position.	Assessment will be performed before, immediately after, and 30 minutes following the administration of the intervention in a single visit
Touch perception using Semmes Weinstein monofilament testing	Touch perception will be assessed through Semmes-Weinstein monofilament testing. Roshen scores will be computed based on the filaments that are perceived by the participant. The range of Roschen scores can be from 0 -5. Higher scores mean better touch perception.	Assessment will be performed before, immediately after, and 30 minutes following the administration of the intervention in a single visit
Fine motor control as assessed by visuomotor tracking performance	Fine motor control at the wrist and hands will be measured by evaluating the performance of the participants in tracking various forms of trajectory by moving their wrist and hand in flexion-extension movements.	Assessment will be performed before, immediately after, and 30 minutes after the administration of the intervention in a single visit

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Tremor assessment using TETRAS	The Essential Tremor Rating Assessment Scale (TETRAS) will be used to quantify tremor of the participants. The TETRAS scale ranges from 0 - 64. Higher scores mean worse tremor in the participant.	Assessment will be performed before, immediately after, and 30 minutes after the administration of the intervention in a single visit
Tremor assessment using arm kinematics	Upper limb kinematics using inertial measurement units (IMUs) will be used to quantify tremor of the participants. IMUs will be placed on the hand, forearm, and upper arm of the participants.	Assessment will be performed before, immediately after, and 30 minutes after the administration of the intervention in a single visit

Collaborators and Investigators

• Sponsor: Shirley Ryan AbilityLab
• Investigators: Principal Investigator: Jose L Pons, PhD, Shirley Ryan AbilityLab

Study record dates

Study Major Dates

• Study Start (Actual): January 24, 2025
• Primary Completion (Estimated): July 31, 2027
• Study Completion (Estimated): July 31, 2029

Study Registration Dates

• First Submitted: April 30, 2024
• First Submitted That Met QC Criteria: May 22, 2024
• First Posted (Actual): May 24, 2024

Study Record Updates

• Last Update Posted (Actual): May 25, 2025
• Last Update Submitted That Met QC Criteria: May 21, 2025
• Last Verified: May 1, 2025

More Information

Terms related to this study

• Keywords: Essential Tremor; Proprioception; Fine motor control; Electrical nerve stimulation
• Additional Relevant MeSH Terms: Neurologic Manifestations; Central Nervous System Diseases; Nervous System Diseases; Movement Disorders; Dyskinesias; Tremor; Essential Tremor
• Other Study ID Numbers: STU00217703

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No