Metaplasticity Experimental Design and Comparison of Motor Outcome Measure Sensitivity to Change

Study Overview
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Brief Summary
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The overall objective is to validate the methodology of a metaplasticity experimental design by assessing change in motor excitability after administration of priming transcranial direct current stimulation (tDCS) followed by repetitive transcranial magnetic stimulation (rTMS) in healthy human participants.

Detailed Description
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The overall objective is to validate the methodology of a metaplasticity experimental design by assessing change in motor excitability after administration of priming transcranial direct current stimulation (tDCS) followed by repetitive transcranial magnetic stimulation (rTMS) in healthy human participants. Our primary objective is to compare pre- and post-measures of cortical excitability before priming tDCS (anodal, cathodal or sham) [M1], directly after priming tDCS [M2], directly after inhibitory rTMS [M3], and 10 minutes after inhibitory rTMS [M4]. Our secondary objective is to evaluate the sensitivity of motor excitability outcome measures response to the noninvasive neurostimulation (e.g. rTMS and tDCS). We also aim to compare pre- and post- measures of cortical excitability after inhibitory and excitatory priming of the motor cortex, and to evaluate the sensitivity of motor outcome measures to changes in cortical plasticity.

Official Title
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Metaplasticity in the Human Motor Cortex: Validation of an Experimental Design and Comparison of Motor Outcome Measure Sensitivity to Change

Conditions
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Healthy

Intervention / Treatment
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* Device: rTMS


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Must be at least 18 years of age (all genders, races, ethnicity) Must have no current psychiatric or neurologic issues Must not have any conditions listed in exclusion criteria Must be fluent in English Exclusion Criteria: History of major psychiatric illness Actively using neuropsychoactive medication Legal or mental incompetency Substance use disorder, abuse or dependence, with active use within the last three months Significant medical or neurological illness Prior neurosurgical illness Prior neurosurgical procedure History of seizure History of ECT or TMS treatment within the past there months Presence of a pacemaker, implanted medical pump or device, metal plate, or metal object in skull or eye (including shunts, dental implants, facial tattoos with metallic ink) Pregnant women

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 99 Years

Sexes Eligible for Study
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Female

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: Crossover Assignment
Interventional Model Description: This is a randomized, sham-controlled, double blinded crossover trial.
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Cathodal tDCS + rTMS then Anodal tDCS + rTMS then Sham tDCS + rTMS<br>Participant will receive 10 minutes of cathodal tDCS between M1 and M2 timepoints, and rTMS for 900 1Hz pulses at 0.85 of Resting Motor Threshold at M2. After 1 week washout, participant will receive 10 minutes of anodal tDCS and rTMS for 900 1Hz pulses at 0.85 RMT. After 1 week washout, participant will receive 10 minutes of sham tDCS and rTMS for 900 1 Hz pulses at 0.85 RMT. | Device: rTMS<br>* Between time point M2 and M3, participant will receive 900 pulses of rTMS at 1Hz at 0.85 of M2 resting motor threshold.<br>* Other names: rapid transcranial magnetic stimulation;|
| Active Comparator: Anodal tDCS + rTMS then Sham tDCS + rTMS then Cathodal tDCS + rTMS<br>Participant will receive 10 minutes of anodal tDCS between M1 and M2 timepoints, and rTMS for 900 1Hz pulses at 0.85 of Resting Motor Threshold at M2. After 1 week washout, participant will receive 10 minutes of sham tDCS and rTMS for 900 1 Hz pulses at 0.85 RMT. After 1 week washout, participant will receive 10 minutes of cathodal tDCS and rTMS for 900 1 Hz pulses at 0.85 RMT. | Device: rTMS<br>* Between time point M2 and M3, participant will receive 900 pulses of rTMS at 1Hz at 0.85 of M2 resting motor threshold.<br>* Other names: rapid transcranial magnetic stimulation;|
| Sham Comparator: Sham tDCS + rTMS then Cathodal tDCS + rTMS then Anodal tDCS + rTMS<br>Participant will receive 10 minutes of sham tDCS between M1 and M2 timepoints, and rTMS for 900 1Hz pulses at 0.85 of Resting Motor Threshold at M2. After 1 week washout, participant will receive 10 minutes of cathodal tDCS and rTMS for 900 1 Hz pulses at 0.85 RMT. After 1 week washout, participant will receive 10 minutes of anodal tDCS and rTMS for 900 1 Hz pulses at 0.85 RMT. | Device: rTMS<br>* Between time point M2 and M3, participant will receive 900 pulses of rTMS at 1Hz at 0.85 of M2 resting motor threshold.<br>* Other names: rapid transcranial magnetic stimulation;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percent Change in MEP Amplitude | Percent Change in MEP amplitude over the first dorsal interosseous (FDI) muscle of the right hand | assessed and reported throughout study completion pre- and post- intervention approximately 30 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cortical Silent Period | Change in length of CSP | tDCS + rTMS assessed and reported pre and post (approximately 10 minutes) | 
| Simple Reaction Time | Participants will perform a simple reaction time task. This will be measured in seconds of response after a stimulus. The final outcome will be percent change in the reaction time from pre- to post- intervention. | The final outcome will be percent change in the reaction time from pre- to post- intervention. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Metaplasticity, Motor excitability, rTMS, tDCS