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Updated: May 22, 2026
12:33
Corticospinal Excitability Modulation During Action Observation
Published on: December 31, 2013
Modulation of corticomuscular coherence by peripheral stimuli
Verity M McClelland1, Zoran Cvetkovic, Kerry R Mills
1Academic Unit of Clinical Neurophysiology, King's College London, London, SE5 9RS, UK.
Experimental Brain Research
|April 25, 2012
Summary
Peripheral afferent stimuli, like electrical or mechanical input, influence brain-muscle synchrony (corticomuscular coherence). Functional stimuli significantly modulate this coherence, highlighting its role in sensorimotor integration.
Area of Science:
- Neuroscience
- Motor Control
- Human Physiology
Background:
- Corticomuscular coherence (CMC) quantifies neural synchrony between brain and muscle activity.
- Understanding how afferent input modulates CMC is crucial for sensorimotor integration research.
Purpose of the Study:
- To investigate the impact of peripheral afferent stimuli on corticomuscular coherence (CMC).
- To determine if electrical and mechanical stimuli modulate CMC during a motor task.
Main Methods:
- Recorded electroencephalogram (EEG) and electromyogram (EMG) during a key grip task.
- Applied graded electrical and mechanical stimuli to the index finger and gripped object.
- Analyzed changes in beta-range (14-36 Hz) CMC following stimulation.
Main Results:
- Electrical stimulation of the dominant index finger reduced and then increased beta-range CMC, with effects outlasting immediate reflex responses.
- Mechanical stimuli similarly modulated beta-range CMC.
- Stimulation of the non-dominant index finger did not significantly increase CMC.
Conclusions:
- Both cutaneous and proprioceptive afferents can access circuits generating CMC.
- Functionally relevant stimuli significantly modulate background beta-range CMC.
- Beta-range CMC plays a key role in sensorimotor integration.
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