Fiche publication
Date publication
janvier 2024
Journal
Journal of neurophysiology
Auteurs
Membres identifiés du Cancéropôle Est :
Pr PAPAXANTHIS Charalambos
Tous les auteurs :
Amiez N, Martin A, Gaveau J, Julliand S, Papaxanthis C, Paizis C
Lien Pubmed
Résumé
Local vibration (LV) applied over the muscle tendon constitutes a powerful stimulus to activate the muscle spindle primary (Ia) afferents which project to the spinal level and are conveyed to the cortical level. This study aimed to identify the neuromuscular changes induced by a 30-minute LV-inducing illusions of hand extension on the vibrated flexor carpi radialis (FCR) and the antagonist extensor carpi radialis (ECR) muscles. We studied the change of the maximal voluntary isometric contraction (MVIC, Experiment 1) for carpal flexion and extension, motor evoked potentials (MEPs, Experiment 2), cervicomedullary motor evoked potentials (CMEPs, Experiment 2), and Hoffmann's reflex (H-reflex, Experiment 3) for both muscles at rest. Measurements were performed before (PRE) and at 0, 30, and 60 minutes after LV protocol. A lasting decrease in strength was only observed for the vibrated muscle. The reduction in CMEPs observed for both muscles seems to support a decrease in alpha motoneurons excitability. In contrast, a slight decrease in MEPs responses was observed only for the vibrated muscle. The MEP/CMEP ratio increase suggested greater cortical excitability after LV for both muscles. In addition, the H-reflex largely decreased for the vibrated and the antagonist muscles. The decrease in the H/CMEP ratio for the vibrated muscle supported both pre- and post-synaptic causes of the decrease in the H-reflex. Finally, LV-inducing illusions of movement reduced alpha motoneurons excitability for both muscles with a concomitant increase in cortical excitability.
Mots clés
alpha motoneurons excitability, corticospinal excitability, forearm muscles strength, local vibration, spinal excitability
Référence
J Neurophysiol. 2024 01 10;: