Neurophysiological and Functional Mechanisms of Motor Control and Learning

Study Overview
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Brief Summary
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Noninvasive stimulation of the central nervous system, including transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), has been increasingly used in the investigation of cortical plasticity. The purpose of our study is to understand mechanistically-at the neurophysiological and systems levels-how the brain learns new motor skills. We propose to study the acquisition, consolidation, and retention of motor skill learning in healthy subjects. At the behavioral level, we will use movement kinematics to quantify and characterize movement, which allow us to infer functional strategies used by the brain to reduce movement errors. At a neurophysiological level, we will use TMS to document changes in cortical circuitry, which will allow us to infer neuroplastic changes possibly subserving these strategies. At a systems level, we will enhance motor system excitability using tDCS, which will enable us to infer the contribution of the stimulated area to the motor system's ability to learn new skills.

Official Title
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Neurophysiological and Functional Mechanisms of Motor Control and Learning

Conditions
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Transcranial Direct Current Stimulation

Intervention / Treatment
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* Device: tDCS-NeuroConn.
* Device: TMS - Magstim.
* Device: Sham tDCS


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Right-handed dominance Ability to give informed consent Exclusion Criteria: active and/or chronic neurological, psychiatric (including depression), or medical conditions psychoactive medication use active drug/alcohol dependence or abuse history homelessness or other social situation that would preclude consistent visits history of head injury (including neurosurgery) history of seizure inability to comprehend or participate in the procedures involved metal in the head (besides in mouth), such as implanted electrodes or devices, shrapnel, surgical clips, or fragments from welding/metalwork implanted devices (such as cardiac pacemakers, medical pumps, or intracardiac lines) in the thorax

Ages Eligible for Study
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Minimum Age: 18 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: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Transcranial direct current stimulator (tDCS)<br>tDCS is delivered noninvasively via electrodes applied to the surface of the head, and a mild electrical current is given during motor training. | Device: tDCS-NeuroConn.<br>* tDCS is delivered noninvasively via electrodes applied to the surface of the head, and a mild electrical current is given during motor training.<br>|
| Active Comparator: Transcranial magnetic stimulation (TMS)<br>TMS is delivered noninvasively via a hand-held coil applied to the surface of the head, and a magnetic pulse probes cortical circuitry [this is not repetitive TMS and so does NOT modulate brain excitability.] | Device: TMS - Magstim.<br>* TMS is delivered noninvasively via a hand-held coil applied to the surface of the head, and a magnetic pulse probes cortical circuitry [this is not repetitive TMS and so does NOT modulate brain excitability<br>|
| Placebo Comparator: Sham-tDCS<br>delivered by briefly turning on and off the stimulator at the beginning of training, which mimics the sensation of true stimulation. | Device: Sham tDCS<br>* delivered by briefly turning on and off the stimulator at the beginning of training, which mimics the sensation of true stimulation.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Motor skill gain from day 1 to day 5 | defined as an improvement in performance accuracy at fixed movement speeds (see 5.2 for description of task and outcome). The delta in accuracy between day 1 and day 5 equates to motor skill learning. | 5 Days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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transcranial magnetic stimulation