| Autor: |
Cretu AL; Neural Control of Movement Lab, Department of Health Science and Technology, Swiss Federal Institute of Technology Zurich, Zurich, Switzerland. andreea.cretu@hest.ethz.ch., Ruddy KL; Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland., Post A; Neural Control of Movement Lab, Department of Health Science and Technology, Swiss Federal Institute of Technology Zurich, Zurich, Switzerland., Wenderoth N; Neural Control of Movement Lab, Department of Health Science and Technology, Swiss Federal Institute of Technology Zurich, Zurich, Switzerland. |
| Jazyk: |
angličtina |
| Zdroj: |
Experimental brain research [Exp Brain Res] 2020 Aug; Vol. 238 (7-8), pp. 1735-1744. Date of Electronic Publication: 2020 Apr 07. |
| DOI: |
10.1007/s00221-020-05801-2 |
| Abstrakt: |
Single-pulse transcranial magnetic stimulation (spTMS) studies report that movement observation facilitates corticospinal excitability in primary motor cortex (M1) in a muscle-specific manner. However, motor evoked potentials (MEPs) elicited by spTMS are known to reflect the summation of several descending volleys in corticospinal neurons which are evoked via mono- and polysynaptic inputs (so-called indirect waves or I-waves). It is unclear which of these components contribute to the muscle-specific modulation of M1 during action observation. The interactions between different I-waves are reflected in the facilitatory peaks elicited with a short-intracortical facilitation (SICF) protocol when two pulses are sent to M1 at precise intervals (i.e., 1.3, 2.5 or 4.1 ms). Here, we explored the modulation of early and late SICF peaks during action observation by measuring highly specific MEP amplitude changes measured in two muscles (index, FDI and little finger, ADM) while participants observed two different actions (precision and whole-hand grip). Our results demonstrate that both early (1.3 ms) and late (2.5 and 4.1 ms) SICF peaks are modulated in the context of movement observation. However, only the second peak (ISI 2.5 ms) was significantly associated with the muscle-specific modulation of corticospinal excitability as measured with spTMS. This late SICF peak is believed to reflect the activity cortico-cortical pathways involved in the facilitation of muscle-specific representations in M1. Thus, our findings suggest that movement observation leads to widespread activation of different neural circuits within M1, including those mediating cortico-cortical communication. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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