Physiological arousal accompanying postural responses to external perturbations after stroke

Research output: Contribution to journalArticlepeer-review

Authors

  • C.L. Pollock
  • M.G. Carpenter
  • M.A. Hunt
  • T.M. Vieira
  • T.D. Ivanova
  • S.J. Garland

Colleges, School and Institutes

Abstract

Objective: The purpose of this study was to examine simultaneously the level of physiological arousal and the postural response to external perturbations in people post-stroke compared to age-matched controls to build a more comprehensive understanding of the effect of stroke on postural control and balance self-efficacy.

Methods: Participants stood with each foot on separate force platforms. Ten applications of loads of 2% body weight at the hips perturbed the participant anteriorly under two conditions: investigator-triggered or self-triggered (total 20). Electrodermal activity (EDA; measurement of physiological arousal), electromyography (EMG) of the ankle plantarflexor muscles and anterior-posterior center of pressure measurements were taken pre-perturbation (anticipatory) and post-perturbation (response) and compared between the initial (first two) and final (last two) perturbations.

Results: Participants post-stroke demonstrated significantly higher levels of anticipatory EDA and anticipatory paretic plantarflexor EMG during both self- and investigator-triggered conditions compared to controls. Anticipatory EDA levels were higher in the final perturbations in participants post-stroke in both conditions, but not in controls. Habituation of the EDA responses post-perturbation was exhibited in the self-triggered perturbations in controls, but not in participants post-stroke.

Conclusions: Physiological arousal and postural control strategies of controls revealed habituation in response to self-triggered perturbations, whereas this was not seen in participants post-stroke.

Significance: Understanding the physiological arousal response to challenges to standing balance post-stroke furthers our understanding of postural control mechanisms post-stroke.

Details

Original languageEnglish
Pages (from-to)935-944
Number of pages10
JournalClinical Neurophysiology
Volume128
Issue number6
Early online date18 Mar 2017
Publication statusPublished - 1 Jun 2017

Keywords

  • Stroke, Physiological arousal, Postural control, External perturbation