Abstract
Spatial navigation requires integration of sensory signals generated during movement such as vision, proprioception and vestibular information. Individuals with Parkinson's disease (PD) are known to veer and this may be due proprioceptive or visuospatial deficits, yet the link between these deficits and veering has yet to be studied. Given that PD is generally a unilateral disorder, the main objective of this study was to evaluate whether the side affected (LPD or RPD) influenced the direction and magnitude of off-path veering. Thirteen individuals with PD (7 LPD, 6 RPD) completed this study. The participants were examined on three walking conditions in complete darkness: 1) toward a target 2) into open space 3) into open space but limbs illuminated with glow in the dark tape. Both groups deviated to the left side of the path. The magnitude of veering towards the left side was significantly greater in LPD (F(1,11)=6.48, p<0.05) and the LPD trended toward greater variability in the mediolateral axis (F(1,11)=3.88, p=0.07). Both outcome measures were significantly influenced by sensory feedback. When the participants were given additional proprioceptive feedback through illumination of their limbs both measures significantly improved. Further discussion of results will be presented in terms of hemispheric processing of sensory feedback in PD.Acknowledgments: NSERC, CIHR, CFI