Influence of vestibular sensory illusion on acute and adaptive postural responses in individuals with Parkinson Disease and healthy controls

Update item information
Publication Type dissertation
School or College College of Health
Department Health & Kinesiology
Author Lester, Mark Eric
Title Influence of vestibular sensory illusion on acute and adaptive postural responses in individuals with Parkinson Disease and healthy controls
Date 2014-08
Description Integration of sensory inputs by the central nervous system (CNS) is necessary for adequate postural stability, but diminishes with age and is further impaired in Parkinson disease (PD). As a result, the CNS cannot appropriately weight sensory stimuli to facilitate postural responses to sudden changes in sensory input. Training the sensorimotor system to ignore or rapidly adapt to aberrant postural cues may improve postural control in PD. We evaluated the influence of acute and repeated exposure to galvanic vestibular stimulation (GVS) on postural responses during static and dynamic tasks to determine whether training improved these responses. We hypothesized that individuals with PD would demonstrate impaired postural recovery responses to acute GVS relative to healthy controls and that individuals with PD and healthy elders would demonstrate diminished adaptive responses to repeated GVS compared to young adults. Twelve individuals with PD (PD group), 15 healthy young adults (HY group), and 11 healthy elders (HE group) participated. Timing of GVS was randomly applied during each task. Fifteen acquisition and nine retention trials with GVS were compared to assess learning. The PD group took longer to stabilize their center of pressure (COP) in quiet stance following GVS acutely compared to controls. The PD and HE groups had lower sample entropy (SaEn) compared to the HY. Neither the PD nor HE groups demonstrated changes in SaEn or meaningful improvements in postural control during acquisition or retention. SaEn in the HY group acutely decreased and then increased at retention which coincided with a meaningful improvement in postural control. The PD group had impaired motor planning, postural preparation, and postural stability during a rise to toes task following acute GVS, but these constructs returned to baseline at later acquisition and retention time points. Controls suppressed GVS acutely Postural coordination decreased acutely in the PD group during tether release. This persisted and an adaptive trend in BOS transition was noted with repeated GVS exposure in this group. No changes were observed in the control groups. Taken together, these results demonstrated that acute GVS differentially affects postural control in individuals with PD. Our results support the hypothesis that reweighting of sensory stimuli is impaired in PD. We also show that individuals with PD are able to suppress attention to a vestibular illusion and demonstrate adaptive responses to a postural threat.
Type Text
Publisher University of Utah
Subject Biomechanics; Galvanic vestibular stimulation; Motor control; Motor learning; Parkinson disease; Postural control
Dissertation Institution University of Utah
Dissertation Name Doctor of Philosophy
Language eng
Rights Management Copyright © Mark Eric Lester 2014
Format Medium application/pdf
Format Extent 1,128,015 bytes
Identifier etd3/id/3179
ARK ark:/87278/s66d927w
Setname ir_etd
Date Created 2014-10-29
Date Modified 2021-05-06
ID 196745
Reference URL