Cervical Neuromodulation and Nociceptive Processing

Study Overview
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Brief Summary
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Several studies have demonstrated that direct currents delivered through the skin at the level of the lumbar spinal cord can influence spinal cord function. In human volunteers, anodal lumbar transcutaneous spinal direct current stimulation (tsDCS) alters spinal processing of nociceptive inputs. Whether cervical tsDCS is able to do the same is less well known.

Detailed Description
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The investigators will compare the effects on the nociceptive processing of healthy volunteers of cervical and lumbar tsDCS. This study will be a double-blinded, sham-controlled, cross-over trial. Each participant will undergo two experimental sessions (anodal cervical tsDCS and sham lumbar tsDCS vs. sham cervical tsDCS and anodal lumbar tsDCS), separated by at least one week.

Official Title
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Effect of the Neuromodulation of the Cervical Spinal Cord on Nociceptive Processing in Healthy Volunteers - a Randomized, Double-blinded Study

Conditions
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Nociceptive Pain

Intervention / Treatment
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* Device: Starstim (Neuroelectrics)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - Healthy young adults Exclusion Criteria: Known medical conditions (e.g., diabetes, neuropathy, psychiatric disorders, seizure, migraine, pacemaker or other implanted medical devices...) Use of any medication (except contraception)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 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: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Anodal tsDCS (cervical active, lumbar sham)<br>Participants will receive: 20 minutes of 2.5 milliampere (mA) anodal tsDCS at the cervical level. sham tsDCS at the lumbar level. | Device: Starstim (Neuroelectrics)<br>* Anodal transcutaneous spinal direct current stimulation (a-tsDCS)<br>|
| Active Comparator: Anodal tsDCS (cervical sham, lumbar active)<br>Participants will receive: 20 minutes of 2.5 milliampere (mA) anodal tsDCS at the lumbar level. sham tsDCS at the cervical level. | Device: Starstim (Neuroelectrics)<br>* Anodal transcutaneous spinal direct current stimulation (a-tsDCS)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in contact-heat evoked potentials amplitude | N2/P2 amplitude | Change from Baseline, at 15-minutes after the end of stimulation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in intensity of perception to contact-heat nociceptive stimuli | Difference in temperature (°C) needed to elicit a pain sensation of similar intensity in the upper and lower limb | Change from Baseline, at 15-minutes after the end of stimulation | 
| Change in temporal summation of pain | Wind-up ratio (WUR) to mechanical pinprick stimuli | Change from Baseline, at 15-minutes after the end of stimulation | 
| Change in intensity of perception to mechanical pinprick nociceptive stimuli | Numerical rating scale (0-100) | Change from Baseline, at 15-minutes after the end of stimulation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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tsDCS, non-invasive neuromodulation, healthy volunteers