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Down regulation of vestibular balance stabilizing mechanisms to enable transition between motor states.

ABSTRACT: The neural control of transition between posture and movement encompasses the regulation of reflex-stabilizing mechanisms to enable motion. Optimal feedback theory suggests that such transitions require the disengagement of one motor control policy before the implementation of another. To test this possibility, we investigated the continuity of the vestibular control of balance during transitions between quiet standing and locomotion and between two standing postures. Healthy subjects initiated and terminated locomotion or shifted the distribution of their weight between their feet, while exposed to electrical vestibular stimuli (EVS). The relationship between EVS and ground reaction forces was quantified using time-frequency analyses. Discontinuities corresponding to null coherence periods were observed preceding the onset of movement initiation and during the step preceding locomotion termination. These results show humans interrupt the vestibular balance stabilizing mechanisms to transition between motor states, suggesting a discrete change between motor control policies, as predicted by optimal feedback theory.

SUBMITTER: Tisserand R

PROVIDER: S-EPMC6056236 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Down regulation of vestibular balance stabilizing mechanisms to enable transition between motor states.

Tisserand Romain R Dakin Christopher J CJ Van der Loos Machiel Hf MH Croft Elizabeth A EA Inglis Timothy J TJ Blouin Jean-Sébastien JS

eLife 20180710

The neural control of transition between posture and movement encompasses the regulation of reflex-stabilizing mechanisms to enable motion. Optimal feedback theory suggests that such transitions require the disengagement of one motor control policy before the implementation of another. To test this possibility, we investigated the continuity of the vestibular control of balance during transitions between quiet standing and locomotion and between two standing postures. Healthy subjects initiated ...[more]

PMID: 29989550

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Dataset Information

Down regulation of vestibular balance stabilizing mechanisms to enable transition between motor states.

Publications

Down regulation of vestibular balance stabilizing mechanisms to enable transition between motor states.

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