Investigating Motor Cortex Processing for Pain Modulation

Study Overview
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Brief Summary
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The purpose of this study is to investigate the effects of different types of interventions (motor learning, somatosensory learning, observation task, mental imagery and tDCS) on the perception of pain and motor cortex excitability in healthy male subjects. This is an exploratory study of healthy subjects only.

Detailed Description
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There are 5 experiments: Exp1: motor learning (3 groups, crossover) - motor leaning with and without visual feedback and a control group. Exp2: sensory learning (4 groups, parallel) - sensory learning with and without feedback, an simple activation task and a control group. Exp3: observational task (2 groups, parallel) - an motor observational task and a control group. Exp4: mental imagery (2 groups, parallel) - a motor mental imagery and a control group. Exp5: tDCS over the motor cortex (2 groups, crossover) - active and sham tDCS. Note that this study has never been completed.

Official Title
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Investigating Motor Cortex Processing for Pain Modulation

Conditions
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Motor Activity

Intervention / Treatment
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* Behavioral: Motor Learning
* Behavioral: Somatosensory Learning
* Behavioral: Observational Task
* Behavioral: Mental Imagery
* Device: transcranial direct current stimulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria Provide informed consent to participate in the study 18 to 64 years old No presence of rheumatologic disease as self reported No clinically significant or unstable medical or psychiatric disorder as self reported No history of alcohol or substance abuse within the last 6 months as self reported No neuropsychiatric co-morbidity as self reported No Contraindications to single pulse TMS (TMS will be used to measure cortical excitability) history of seizures unexplained loss of consciousness metal in the head frequent or severe headaches or neck pain implanted brain medical devices No Contraindications to tDCS metal in the head implanted brain medical devices

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 64 Years

Sexes Eligible for Study
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Male

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: Parallel Assignment
Interventional Model Description: There are 5 experiments: motor learning (3 groups, crossover), sensory learning (4 groups, parallel), observational task (2 groups, parallel), mental imagery (2 groups, parallel), and tDCS over the motor cortex (2 groups, crossover). Please note that the tDCS experiment has never been conducted.
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Motor Learning (ML) sighted<br>In this arm, subject will perform motor Learning with visual feedback - ML sighted. There will be an anticipated total of 15 subjects in this experimental arm. This arm will be conducted as a cross-over design. The subjects will undergo the three interventions listed (motor learning with visual feedback, motor learning without visual feedback, and control group) in a counterbalanced randomized order. There will be at least 24 hours between each experimental session. | Behavioral: Motor Learning<br>* Subject will have to draw a set of shapes and words during 20 minutes.<br>|
| Experimental: Motor Learning (ML) blind<br>In this arm, subject will perform motor Learning without visual feedback - ML blind. There will be an anticipated total of 15 subjects in this experimental arm. This arm will be conducted as a cross-over design. The subjects will undergo the three interventions listed (motor learning with visual feedback, motor learning without visual feedback, and control group) in a counterbalanced randomized order. There will be at least 24 hours between each experimental session. | Behavioral: Motor Learning<br>* Subject will have to draw a set of shapes and words during 20 minutes.<br>|
| Placebo Comparator: Motor Learning (ML) control group<br>In this arm, subject will perform simple hand movements - control group. There will be an anticipated total of 15 subjects in this experimental arm. This arm will be conducted as a cross-over design. The subjects will undergo the three interventions listed (motor learning with visual feedback, motor learning without visual feedback, and control group) in a counterbalanced randomized order. There will be at least 24 hours between each experimental session. | Behavioral: Motor Learning<br>* Subject will have to draw a set of shapes and words during 20 minutes.<br>|
| Experimental: Somatosensory Learning (SL sighted)<br>In this arm, subject will perform sensory Learning with visual feedback - SL sighted. There will be an anticipated total of 10 subjects in this experimental arm. This experimental arm will be conducted in a parallel design with 4 groups (SL sighted, SL blind, Sactivation, SL control). | Behavioral: Somatosensory Learning<br>* Subjects will perform a learning task involving sensory activation of the hand. The task will consist of learning letters of Braille.<br>|
| Experimental: Somatosensory Learning (SL blind)<br>In this arm, subject will perform sensory Learning without visual feedback - SL blind. There will be an anticipated total of 10 subjects in this experimental arm. This experimental arm will be conducted in a parallel design with 4 groups (SL sighted, SL blind, Sactivation, SL control). | Behavioral: Somatosensory Learning<br>* Subjects will perform a learning task involving sensory activation of the hand. The task will consist of learning letters of Braille.<br>|
| Experimental: Somatosensory Activation (S activation)<br>In this arm, subject will receive simple sensory stimulation over their left index finger - Sactivation. There will be an anticipated total of 10 subjects in this experimental arm.This experimental arm will be conducted in a parallel design with 4 groups (SL sighted, SL blind, Sactivation, SL control). | Behavioral: Somatosensory Learning<br>* Subjects will perform a learning task involving sensory activation of the hand. The task will consist of learning letters of Braille.<br>|
| Placebo Comparator: Somatosensory Learning (SL) control group<br>In this arm,the subjects will not receive any somatosensory input (SL control group). There will be an anticipated total of 10 subjects in this experimental arm. This experimental arm will be conducted in a parallel design with 4 groups (SL sighted, SL blind, Sactivation, SL control). | Behavioral: Somatosensory Learning<br>* Subjects will perform a learning task involving sensory activation of the hand. The task will consist of learning letters of Braille.<br>|
| Experimental: Observational Task (OT) - real<br>In this arm, the subjects will perform an observational task - observation of hand movements. This experimental arm will be conducted in a parallel design. There will be 15 subjects per intervention. | Behavioral: Observational Task<br>* Subjects will watch a 10 second video of a right-handed person performing movements of their left index finger. Subjects will be instructed to watch the video without any other specific instruction.<br>|
| Placebo Comparator: Observational Task (OT) - control group<br>In this arm, the subjects will perform a controlled observational task - observation of geometric shapes. This experimental arm will be conducted in a parallel design. There will be 15 subjects per intervention. | Behavioral: Observational Task<br>* Subjects will watch a 10 second video of a right-handed person performing movements of their left index finger. Subjects will be instructed to watch the video without any other specific instruction.<br>|
| Experimental: Mental Imagery (MI) - real<br>In this arm, the subjects will perform mental imagery - mental imagery of finger movements. This experimental arm will be conducted in a parallel design. There will be 15 subjects per intervention. | Behavioral: Mental Imagery<br>* Subjects will be asked to perform mental imagery of motor practice - finger movements of the left hand for 10 minutes.<br>|
| Placebo Comparator: Mental Imagery (MI) - control group<br>In this arm, the subjects will perform a controlled task - simple mental calculation. This experimental arm will be conducted in a parallel design. There will be 15 subjects per intervention. | Behavioral: Mental Imagery<br>* Subjects will be asked to perform mental imagery of motor practice - finger movements of the left hand for 10 minutes.<br>|
| Experimental: transcranial direct current stimulation - tDCS real<br>tDCS will be applied over the motor cortex for 20minutes at an intensity of 2mA. 15 subjects will be enrolled. The subjects will undergo two interventions, real and sham in a counterbalanced randomized order. There will be at least 3 days between each experimental session. | Device: transcranial direct current stimulation<br>* Subjects will undergo active and sham tDCS stimulation in a randomized and counterbalanced order. During both active and sham stimulation, we will use electrodes of 35cm^2, intensity of 2mA for a duration of 20 minutes. The anode electrode will be placed over the right primary motor cortex (M1) and the cathode will be placed over the contralateral supraorbital area. For active stimulation, the current will be on for the duration of 20 minutes. For sham stimulation, the current will ramp up, and then down again for 30 seconds to simulate the sensation of active tDCS.<br>|
| Placebo Comparator: transcranial direct current stimulation - tDCS sham<br>tDCS will be applied over the motor cortex for 20minutes at an intensity of 2mA. The stimulation will be stopped after 30seconds. 15 subjects will be enrolled. The subjects will undergo two interventions, real and sham in a counterbalanced randomized order. There will be at least 3 days between each experimental session. | Device: transcranial direct current stimulation<br>* Subjects will undergo active and sham tDCS stimulation in a randomized and counterbalanced order. During both active and sham stimulation, we will use electrodes of 35cm^2, intensity of 2mA for a duration of 20 minutes. The anode electrode will be placed over the right primary motor cortex (M1) and the cathode will be placed over the contralateral supraorbital area. For active stimulation, the current will be on for the duration of 20 minutes. For sham stimulation, the current will ramp up, and then down again for 30 seconds to simulate the sensation of active tDCS.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Motor Cortex Excitability MEP Amplitude | We aim to assess the effects of the intervention (ML, SL, OT and MI) on motor cortex excitability as measured by the change in motor evoked potential (using transcranial magnetic stimulation) before and after the given intervention. For ML: MEP will be measured before and after each ML sessions in the same subject (crossover design - ML sighted/MLblind/ML control). For SL: MEP will be measured before and after the treatment session in the each groups (parallel design - 1 session per group). For OT: MEP will be measured before and after the treatment session in the each groups (parallel - 1 session per group). For MI: MEP will be measured before and after the treatment session in the each groups (parallel design - 1 session per group). | after each intervention | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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learning, pain perception