Effects of Transcutaneous Electrical Nerve Stimulation on Cortical Excitability in the Primary Motor Cortex in Healthy Adults

Study Overview
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Brief Summary
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Recently, non-invasive brain stimulation has become a powerful tool in both basic research and clinical application. Among several non-invasive brain stimulation techniques, transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS) have received the most attention. About DC stimulation, the change of polarity could modulate the spontaneous neuronal activity and make effect on decision making, language, memory, sensory perception, and pain. In spite of that the concept of transcranial alternating current stimulation (tACS) is not novel, AC is relatively safe compared to DC, and researches have revealed that AC might potentially have the effect on the cortical excitability. However, there are still many areas about AC stimulation which remain unknown, such as mechanism, application, and potential influence on cortical excitability.

Conditions
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Transcutaneous Electrical Nerve Stimulation

Intervention / Treatment
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* Device: transcutaneous electrical nerve stimulation, TENS


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy adults

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: 120Hz alternating current stimulation group<br> | Device: transcutaneous electrical nerve stimulation, TENS<br>* Then participants will receive stimulation for 20 minutes.<br>|
| Active Comparator: 5Hz alternating current stimulation group<br> | Device: transcutaneous electrical nerve stimulation, TENS<br>* Then participants will receive stimulation for 20 minutes.<br>|
| Sham Comparator: sham alternating current stimulation group<br> | Device: transcutaneous electrical nerve stimulation, TENS<br>* Then participants will receive stimulation for 20 minutes.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Motor evoked potential | measure of intracortical inhibition on abductor pollicis brevis by single-pulse TMS. | Baseline | 
| Intracortical inhibition, ICI | Measure of changes in intracortical inhibition on abductor pollicis brevis by paired-pulse TMS. | Baseline,2 hours, 2.5 hours,and 3 hours | 
| intracortical facilitation, ICF | Measure of changes in intracortical inhibition on abductor pollicis brevis by paired-pulse TMS. | Baseline,Baseline,2 hours, 2.5 hours,and 3 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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transcutaneous electrical nerve stimulation, transcranial magnetic stimulation