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Updated: Jul 14, 2026
12:33
Corticospinal Excitability Modulation During Action Observation
Published on: December 31, 2013
Vision without proprioception modulates cortico-spinal excitability during hand motor imagery
C Mercier1, A Aballea, C D Vargas
1Centre de Neuroscience Cognitive CNRS, 67 Blvd. Pinel, 69675 Bron, France.
Cerebral Cortex (New York, N.Y. : 1991)
|May 23, 2007
Summary
Motor imagery facilitation is independent of hand posture without proprioception. However, vision can influence motor representations, suggesting multisensory integration in brain
Area of Science:
- Neuroscience
- Motor Control
- Somatosensation
Background:
- Cortico-spinal facilitation occurs during motor imagery.
- This facilitation is reduced when actual hand posture conflicts with imagined movement.
- The role of proprioception in this interference is unclear.
Purpose of the Study:
- To investigate if online proprioceptive information causes interference during motor imagery.
- To examine the influence of visual feedback on motor imagery in the absence of proprioception.
Main Methods:
- Used transcranial magnetic stimulation (TMS)-induced motor-evoked potentials (MEPs).
- Tested a deafferented subject (G.L.) and 7 controls during motor imagery.
- Manipulated hand posture compatibility with imagined movement, with eyes open and closed.
Main Results:
- G.L. showed facilitation independent of hand posture when proprioception was absent (eyes closed).
- Control subjects showed reduced facilitation with incompatible hand postures.
- When G.L. could see her hand (eyes open), facilitation varied with posture compatibility, similar to controls.
Conclusions:
- Proprioception is not essential for the interference effect during motor imagery.
- Vision can modulate motor representations, acting as a substitute for proprioception.
- Limb position representation in the brain relies on multisensory integration.
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