Neural Operant Conditioning

Study Overview
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Brief Summary
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The goal of this clinical trial is to learn if operant conditioning can reduce spasticity in order to improve walking in stroke patient. The main questions it aims to answer are: Can participants self-regulate reflex excitability Can participants self-regulate reflex, reduce spasticity and improve walking Participants will undergo surface stimulation to evoke spinal reflexes and will be asked to control these reflexes therefore reducing spasticity. Researchers will compare result to able bodied participants to see if [insert effects]

Detailed Description
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The study purpose is to investigate the possibility and later effect of spinal reflex self-regulation in post-stroke stiff-knee gait. The intervention will consist of direct current surface stimulation of the peripheral nerves using electrical stimulation. Stimulation will evoke a motor response that will be collected through surface EMG electrodes and processed to depict a measure of the response as feedback to the participant to complete the loop of operant conditioning. The participant will attempt to modulate their responses over multiple sessions to cause this depiction to either increase or decrease its value depending on an established target. .

Official Title
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Neural Operant Conditioning to Improve Walking After Stroke

Conditions
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Stroke, Chronic Stroke, Gait, Hemiplegic, Gait, Spastic, Walking, Difficulty

Intervention / Treatment
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* Other: Peripheral Nerve Stimulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Sign and date consent form At least 3 months since stroke event Over 18 years of age at time of eligibility Ability to stand upright and walk for at least 5 minutes Premorbidly independent Mild to moderate gait impairment Reduced knee flexion during walking relative to the unimpaired side Unilateral hemiparesis of the lower limbs Ability to evoke muscle responses through peripheral nerve stimulation, spinal cord stimulation, and transcranial magnetic stimulation Medically stable Skin intact on hemiparetic leg, abdomen, and scalp Ability to evoke muscle responses and/or reflex responses through peripheral nerve stimulation, spinal cord stimulation, and/or transcranial magnetic stimulation Exclusion Criteria: Co-existing neurological condition other than prior stroke involving the hemiparetic lower limb (e.g., peripheral nerve injury, PD, SCI, TBI, MS). History of lower limb musculoskeletal injury Functionally relevant osteoarthritis and weight bearing restriction Functionally relevant polyneuropathy resulting in lack of sensation in the lower leg Functionally relevant cognitive impairment Functionally relevant vision impairment Pregnant Botox injection to the ipsilateral leg in the last 12 weeks or taking oral anti-spasticity medications Taking part in physical therapy for any walking-related impairment Cardiac pacemaker or other implanted electronic systems Uncontrolled seizure disorder Use of seizure lowering threshold medications and the discretion of the study physician Deficits in communication that interfere with reasonable study participation Severely impaired cognition and communication Severe lower limb pain

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Experimental: Post-stroke Stiff-Knee Gait Participants<br>Individuals with post-stroke Stiff-Knee gait | Other: Peripheral Nerve Stimulation<br>* Electrical stimulation of peripheral nerves to measure resulting gait kinematics and surface muscle activity<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Surface electromyographic recording of leg muscles | Recording electrical activity of leg muscles during walking in response to peripheral nerve stimulation | baseline, week 6 -mid-treatment, week 12 - end of treatment, 4-week post treatment, 12 weeks post treatment, 24 weeks post treatment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 10 meter walk test | 10 meter walk test with collection of gait kinematics captured using an inertial motion capture camera system | baseline, week 6 -mid-treatment, week 12 - end of treatment, 4-week post treatment, 12 weeks post treatment, 24 weeks post treatment | 
| quadriceps pendulum test | This is a method of evaluating spasticity using gravity to provoke the muscular stretch reflex allowing for the collection of joint angle data. This data will aid in assessing changes in joint angles as a result of training. | baseline, week 6 -mid-treatment, week 12 - end of treatment, 4-week post treatment, 12 weeks post treatment, 24 weeks post treatment | 
| Five Times Sit to Stand Test | measures lower extremity functional strength. This test will measure your leg strength by asking you to sit down and stand up from a chair 5 times as fast as possible. | baseline, week 6 -mid-treatment, week 12 - end of treatment, 4-week post treatment, 12 weeks post treatment, 24 weeks post treatment | 
| TMS | non-invasive brain stimulation device, will be used to elicit a motor evoked response in participants via low frequency stimulation to the cortical regions associated with the muscles being investigated. This approach will test the integrity of the participant's CST in relation to the intervention and assessments being conducted | Baseline, Week 12 - end of treatment |