Perception of whole-body motion during balance perturbations is impaired in Parkinson's disease and is associated with balance impairment.

ABSTRACT:

Background

In addition to motor deficits, Parkinson's disease (PD) may cause perceptual impairments. The role of perceptual impairments in sensorimotor function is unclear, and has typically been studied in single-joint motions.

Research question

We hypothesized that perception of whole-body motion is impaired in PD and contributes to balance impairments. We tested (1) whether directional acuity to whole body perturbations during standing was worse in people with PD compared to neurotypical older adults (NOA), and (2) whether balance ability, as assessed by the MiniBESTest, was associated with poor directional acuity in either group.

Methods

Participants were exposed to pairs of support-surface translation perturbations in a two-alternative forced choice testing paradigm developed previously in a young healthy population. The first perturbation of each pair that was to be judged by participants was directly backward, and the second perturbation deviated from the left or right from the backward direction by 1°-44°. Participants reported whether the perturbations in each pair were in the "same" or "different" direction. Judgements from 24 to 67 perturbation pairs were used to calculate directional acuity thresholds corresponding to "just-noticeable differences" in perturbation direction. Linear mixed models determined associations between directional thresholds and clinical variables including MDS-UPDRS-III score, age, and MiniBESTest score.

Results

20 PD (64?±?7 y, 12 male, ?12?h since last intake of antiparkinsonian medications) and 12 NOA (64?±?8, 6 male) were assessed. Directional thresholds were higher (worse) among PD participants (17.6?±?5.9° vs. 12.8?±?3.3°, P?SignificancePerception of whole-body motion is impaired in PD and may contribute to impaired balance and falls.

SUBMITTER: Bong SM 

PROVIDER: S-EPMC7015810 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature