Non-invasive Brain Stimulation (NIBS) and Dual-task Walking After Stroke

Study Overview
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Brief Summary
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The study aims to identify neural locus critical for dual-task walking (walking and talking) in individuals with stroke. To achieve this aim, the investigators apply repetitive transcranial magnetic stimulation (rTMS) to different parts of the brain and evaluate the effects of brain stimulation on dual-task walking speed.

Detailed Description
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This study will enroll 12 individuals with a stroke at least 6 months ago. Participants will be tested across 3 sessions and each session will be approximately 1 week apart from each other. During testing, participants will be asked to walk under two conditions: single- and dual-task conditions. Under the single-task condition, participants walk on a instrumented mat such that their gait performance will be captured. Under the dual-task condition, participants walk on the mat while performing a counting backward task. The walking assessment is followed by a 12 minute non-invasive brain stimulation using high frequency rTMS. Another walking assessment will be conducted right after the brain stimulation session. High frequency rTMS will be applied to different neural loci, namely primary motor cortex (M1), supplementary motor area (SMA), and dorsolateral prefrontal cortex (DLPFC). The walking speed under two different conditions will be compared before and after brain stimulation to different neural loci.

Official Title
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Efficacy of Non-Invasive Brain Stimulation on Dual-Task Walking After Stroke: A Repetitive Transcranial Magnetic Stimulation (rTMS) Study

Conditions
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Stroke

Intervention / Treatment
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* Device: high frequency rTMS


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age above 18 years Diagnosis of Left hemispheric stroke at least 6 months ago First time stroke OR complete gait recovery from prior stroke Able to walk independently for at least 10 meters with or without walking aids Have at least minimal movements (> 5 degree of motion) at the affected ankle Score > 26 on Mini Mental State Exam (MMSE) Ability to participate in the informed consent process Exclusion Criteria: Diagnosis of other neurological conditions, such as Parkinson Disease, Alzheimer, Spinal Cord Injury, Multiple Sclerosis Other comorbidities which could interfere with gait (i.e. amputation, severe osteoarthritis) Unstable clinical conditions Non-ambulatory prior to onset of stroke History of significant head trauma Electrical, magnetic, or mechanical implantation: cardiac pacemakers or intracerebral vascular clip Metal implantation in the oral cavity, head/neck area and lower extremity Pregnancy History of seizures or unexplained loss of consciousness Immediate family member with epilepsy Use of seizure threshold lowering medicine Current abuse of alcohol or drugs Anticipated inability to complete the study History of psychiatric illness requiring medication control

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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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: High frequency rTMS<br>High frequency rTMS will be applied to different neural loci based on the randomized sessions. | Device: high frequency rTMS<br>* Participants receive 16 minutes (5Hz, 24 10-second trains with a inter-train interval of 30s) of high frequency rTMS applied to either primary motor cortex (M1), supplementary motor area (SMA) and dorsolateral prefrontal cortex (DLPFC) at different sessions. Walking performance is evaluated before and after the brain stimulation.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Gait Speed | gait speed in m/s will be captured using GaitRite gait assessment walkway | before and 10 minutes after the non-invasive brain stimulation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Step Lengths | Step lengths in centimeter (cm) will be captured using GaitRite gait assessment walkway | before and 10 minutes after the non-invasive brain stimulation | 
| Change in Single Support Times | Single support times (in % of gait cycle) will be captured using GaitRite gait assessment walkway | before and 10 minutes after the non-invasive brain stimulation | 
| Change in Counting Task Performance | number of correct responses in counting backward task | before and 10 minutes after the non-invasive brain stimulation |