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Updated: Jul 25, 2026
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Assessment of Neuromuscular Function Using Percutaneous Electrical Nerve Stimulation
Published on: September 13, 2015
Contralateral intramuscular acupuncture-like electrical stimulation differentially changes the short-latency
N J Dawson1, O C Lippold, R J Milne
1Department of Physiology, School of Medicine, University of Auckland, New Zealand.
Experimental Neurology
|October 1, 1987
Summary
Nonspecific electrical stimulation of one arm can reduce reflex responses in the other arm. This effect, observed in the M1 reflex component, may involve changes in muscle spindle activity or neural pathway inhibition.
Area of Science:
- Neuroscience
- Physiology
- Biomedical Engineering
Background:
- Surface electromyography (EMG) measures muscle electrical activity.
- Reflex responses are involuntary muscle actions.
- The M1 and M2 components represent early and late phases of reflex responses.
Purpose of the Study:
- To investigate the effect of contralateral arm electrical stimulation on reflex responses in human muscles.
- To determine if intramuscular electrical stimulation influences specific reflex components (M1 and M2).
Main Methods:
- Electromyographic activity was recorded from the first dorsal interosseous and extensor digitorum communis muscles.
- Reflexes were elicited by muscle stretch and electrical stimulation of the ulnar nerve.
- Nonspecific, low-frequency electrical stimulation was applied to the contralateral arm via intramuscular electrodes.
Main Results:
- Contralateral intramuscular electrical stimulation depressed the M1 reflex response of the extensor digitorum communis by 37%.
- This depression effect persisted during and after the stimulation period.
- The M1 response to muscle stretch was reduced, but the M1 response to electrical nerve stimulation was unaffected.
Conclusions:
- Nonspecific intramuscular electrical stimulation of one arm can reduce the M1 reflex component of contralateral muscle stretch responses.
- The mechanism may involve either reduced fusimotor activity or inhibition of oligosynaptic pathways contributing to early reflex responses.
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