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The Evoked Potential Operant Conditioning System (EPOCS): A Research Tool and an Emerging Therapy for Chronic Neuromuscular Disorders
Published on: August 25, 2022
Soleus H-reflex operant conditioning changes the H-reflex recruitment curve
Aiko K Thompson1, Xiang Yang Chen, Jonathan R Wolpaw
1Helen Hayes Hospital, New York State Department of Health, Route 9W, West Haverstraw, New York 10993, USA. thompsona@helenhayeshosp.org
Muscle & Nerve
|January 3, 2013
Summary
Operant conditioning alters the human soleus H-reflex across various stimulus strengths, not just at M-wave threshold. This suggests broader implications for motor control and actions involving this neural pathway.
Area of Science:
- Neuroscience
- Motor Control
- Human Physiology
Background:
- Operant conditioning can modify the human soleus H-reflex.
- Previous protocols focused conditioning near M-wave threshold.
Purpose of the Study:
- To investigate the impact of conditioning on H-reflexes at multiple stimulus strengths.
- To determine if conditioning affects the entire H-reflex recruitment curve.
Main Methods:
- H-reflex recruitment curves were measured before and after conditioning.
- Participants underwent 24 sessions of either up-conditioning (HRup) or down-conditioning (HRdown).
Main Results:
- Conditioning affected the entire H-reflex recruitment curve in all subjects.
- Most HRup subjects showed an elevated curve; most HRdown subjects showed a depressed curve.
- Some subjects exhibited a leftward (HRup) or rightward (HRdown) shift in their recruitment curve.
Conclusions:
- H-reflex conditioning influences responses across a range of stimulus intensities.
- These findings suggest conditioning has widespread effects on motor pathways.
- The study highlights the plasticity of spinal reflex pathways.
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