Skip to Main content Skip to Navigation
Journal articles

Do Gravity-Related Sensory Information Enable the Enhancement of Cortical Proprioceptive Inputs When Planning a Step in Microgravity?

Abstract : We recently found that the cortical response to proprioceptive stimulation was greater when participants were planning a step than when they stood still, and that this sensory facilitation was suppressed in microgravity. The aim of the present study was to test whether the absence of gravity-related sensory afferents during movement planning in microgravity prevented the proprioceptive cortical processing to be enhanced. We reestablished a reference frame in microgravity by providing and translating a horizontal support on which the participants were standing and verified whether this procedure restored the proprioceptive facilitation. The slight translation of the base of support (lateral direction), which occurred prior to step initiation, stimulated at least cutaneous and vestibular receptors. The sensitivity to proprioceptive stimulation was assessed by measuring the amplitude of the cortical somatosensory-evoked potential (SEP, over the Cz electrode) following the vibration of the leg muscle. The vibration lasted 1 s and the participants were asked to either initiate a step at the vibration offset or to remain still. We found that the early SEP (90–160 ms) was smaller when the platform was translated than when it remained stationary, revealing the existence of an interference phenomenon (i.e., when proprioceptive stimulation is preceded by the stimulation of different sensory modalities evoked by the platform translation). By contrast, the late SEP (550 ms post proprioceptive stimulation onset) was greater when the translation preceded the vibration compared to a condition without pre-stimulation (i.e., no translation). This suggests that restoring a body reference system which is impaired in microgravity allowed a greater proprioceptive cortical processing. Importantly, however, the late SEP was similarly increased when participants either produced a step or remained still. We propose that the absence of step-induced facilitation of proprioceptive cortical processing results from a decreased weight of proprioception in the absence of balance constraints in microgravity.
Document type :
Journal articles
Complete list of metadata

Cited literature [71 references]  Display  Hide  Download

https://hal.archives-ouvertes.fr/hal-01384074
Contributor : Simon Moré Connect in order to contact the contributor
Submitted on : Tuesday, November 29, 2016 - 11:22:15 AM
Last modification on : Thursday, July 14, 2022 - 4:02:54 AM
Long-term archiving on: : Tuesday, March 21, 2017 - 12:12:00 PM

File

journal.pone.0108636.PDF
Publisher files allowed on an open archive

Identifiers

Collections

Citation

Anahid H. Saradjian, Dany Paleressompoulle, Didier Louber, Thelma Coyle, Jean Blouin, et al.. Do Gravity-Related Sensory Information Enable the Enhancement of Cortical Proprioceptive Inputs When Planning a Step in Microgravity?. PLoS ONE, Public Library of Science, 2014, 9 (9), ⟨10.1371/journal.pone.0108636⟩. ⟨hal-01384074⟩

Share

Metrics

Record views

117

Files downloads

45