Zacharie Beaulne-Séguin1, Julie Nantel2. 1. School of Human Kinetics, Faculty of Health Sciences, Ottawa University, Canada. 2. School of Human Kinetics, Faculty of Health Sciences, Ottawa University, Canada. Electronic address: jnantel@uottawa.ca.
Abstract
INTRODUCTION: We asked whether conflicting visual cues influences gait initiation, gait inhibition and postural control in Parkinson's disease (PD) between freezers, non-freezers and healthy older adults. METHODS: Twenty-five PD participants on dopaminergic medication and 17 healthy older adults were asked to initiate or refrain gait depending on visual cues: green GO (GG), green STOP (GS), red GO (RG), red STOP (RS). Center of pressure (CoP) displacement, variability and mean velocity (VCoP) in the anterior-posterior (AP) and medial-lateral (ML) directions and movement time (MT) were measured. RESULTS: Gait initiation: Both freezers and non-freezers were different from controls in GG and GS. In GS, freezers had smaller CoP displacement and velocity in both directions (p<0.01), while non-freezers had smaller VCoP in AP and ML (p<0.01). AP CoP displacement in GS was smaller in freezers compared to non-freezers (p<0.05). Freezers had longer MT compared to controls in GG and compared to both groups in GS (p<0.01). Gait inhibition: Controls and freezers had larger CoP displacement variability (p<0.05) and velocity (p<0.01) in both directions in RG compared to RS. No differences were seen in non-freezers. Three freezers initiated walking during the RG or RS conditions. CONCLUSION: Freezers were in general slower at initiating gait, displayed a more restrictive postural strategy and were more affected by the conflicting conditions compared to both controls and non-freezers. In freezers, the conflicting visual cues may have increased the cognitive load enough to provoke delays in processing the visual information and implementing the appropriate motor program.
INTRODUCTION: We asked whether conflicting visual cues influences gait initiation, gait inhibition and postural control in Parkinson's disease (PD) between freezers, non-freezers and healthy older adults. METHODS: Twenty-five PDparticipants on dopaminergic medication and 17 healthy older adults were asked to initiate or refrain gait depending on visual cues: green GO (GG), green STOP (GS), red GO (RG), red STOP (RS). Center of pressure (CoP) displacement, variability and mean velocity (VCoP) in the anterior-posterior (AP) and medial-lateral (ML) directions and movement time (MT) were measured. RESULTS: Gait initiation: Both freezers and non-freezers were different from controls in GG and GS. In GS, freezers had smaller CoP displacement and velocity in both directions (p<0.01), while non-freezers had smaller VCoP in AP and ML (p<0.01). AP CoP displacement in GS was smaller in freezers compared to non-freezers (p<0.05). Freezers had longer MT compared to controls in GG and compared to both groups in GS (p<0.01). Gait inhibition: Controls and freezers had larger CoP displacement variability (p<0.05) and velocity (p<0.01) in both directions in RG compared to RS. No differences were seen in non-freezers. Three freezers initiated walking during the RG or RS conditions. CONCLUSION: Freezers were in general slower at initiating gait, displayed a more restrictive postural strategy and were more affected by the conflicting conditions compared to both controls and non-freezers. In freezers, the conflicting visual cues may have increased the cognitive load enough to provoke delays in processing the visual information and implementing the appropriate motor program.
Authors: Daniel S Peterson; Katrijn Smulders; Martina Mancini; John G Nutt; Fay B Horak; Brett W Fling Journal: J Int Neuropsychol Soc Date: 2020-12-09 Impact factor: 2.892
Authors: Bastiaan R Bloem; Jan H L Ypinga; Allison Willis; Colleen G Canning; Roger A Barker; Marten Munneke; Nienke M De Vries Journal: J Parkinsons Dis Date: 2018 Impact factor: 5.568