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Souza WH, Zobeiri OA, Millar JL, Cullen KE, Schubert MC. Aging Delays Completion of Head Rotation Cycles in Continuous Gaze Stabilization Exercises despite Putative Healthy Vestibular Function. Gerontology 2024:1-15. [PMID: 39111296 DOI: 10.1159/000540230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 07/01/2024] [Indexed: 09/13/2024] Open
Abstract
INTRODUCTION Aging is associated with loss of balance, with falls being one of the leading causes of death among the elderly in the USA. Gaze stabilization exercises (GSE) improve balance control in vestibular populations and could be useful to prevent falls in healthy individuals. However, the extent to which aging affects head kinematics in GSE is unknown. METHODS Forty-eight younger (n = 25, 24 ± 6 years, 60% female) and older (n = 23, 66 ± 5 years, 56% female) adults completed six 30-s GSE. Participants were asked to maintain gaze fixation on a stationary target while continuously performing head movements in pitch (e.g., vertical) and yaw (e.g., horizontal) directions. The visual target was placed on the wall 1 m or 2 m away or handheld at arm's length. Head kinematics were recorded with an inertial measurement unit placed on the back of the participants' head. RESULTS Older adults took significantly more time (e.g., delay) to complete cycles of head rotation in both pitch and yaw compared to younger participants across all GSE. Such delay was further increased during yaw head rotation while fixating gaze of the 1 m target. The average peak velocity (APV) and average angular displacement (AAD), however, were equivalent between groups in all GSE. CONCLUSION Aging leads to the maintenance of head rotation APV and AAD at the expense of delayed cycles of head rotation, suggesting an age-dependent prioritization strategy (e.g., adapt duration first, range second) during continuous head movements. The distance of the visual target and head movement direction influenced elderly performance and should be considered when prescribing GSE to older populations.
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Affiliation(s)
- Wagner H Souza
- Department of Biomedical Engineering, Cullen Lab, Johns Hopkins University, Baltimore, Maryland, USA,
- Department of Otolaryngology Head and Neck Surgery, Laboratory of Vestibular NeuroAdaptation, Johns Hopkins University, Baltimore, Maryland, USA,
- Toronto Rehabilitation Institute, KITE - University Health Network, Toronto, Ontario, Canada,
| | - Omid A Zobeiri
- Department of Biomedical Engineering, Cullen Lab, Johns Hopkins University, Baltimore, Maryland, USA
| | - Jennifer L Millar
- Department of Physical Medicine and Rehabilitation, Johns Hopkins University, Baltimore, Maryland, USA
| | - Kathleen E Cullen
- Department of Biomedical Engineering, Cullen Lab, Johns Hopkins University, Baltimore, Maryland, USA
- Department of Otolaryngology Head and Neck Surgery, Laboratory of Vestibular NeuroAdaptation, Johns Hopkins University, Baltimore, Maryland, USA
- Department of Neuroscience, Johns Hopkins University, Baltimore, Maryland, USA
| | - Michael C Schubert
- Department of Otolaryngology Head and Neck Surgery, Laboratory of Vestibular NeuroAdaptation, Johns Hopkins University, Baltimore, Maryland, USA
- Department of Physical Medicine and Rehabilitation, Johns Hopkins University, Baltimore, Maryland, USA
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de Aquino Costa Sousa T, Gagnon IJ, Li KZH, McFadyen BJ, Lamontagne A. Exploring the challenges of avoiding collisions with virtual pedestrians using a dual-task paradigm in individuals with chronic moderate to severe traumatic brain injury. J Neuroeng Rehabil 2024; 21:80. [PMID: 38755606 PMCID: PMC11097498 DOI: 10.1186/s12984-024-01378-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Accepted: 05/10/2024] [Indexed: 05/18/2024] Open
Abstract
BACKGROUND Individuals with a moderate-to-severe traumatic brain injury (m/sTBI), despite experiencing good locomotor recovery six months post-injury, face challenges in adapting their locomotion to the environment. They also present with altered cognitive functions, which may impact dual-task walking abilities. Whether they present collision avoidance strategies with moving pedestrians that are altered under dual-task conditions, however, remains unclear. This study aimed to compare between individuals with m/sTBI and age-matched control individuals: (1), the locomotor and cognitive costs associated with the concurrent performance of circumventing approaching virtual pedestrians (VRPs) while attending to an auditory-based cognitive task and; (2) gaze behaviour associated with the VRP circumvention task in single and dual-task conditions. METHODOLOGY Twelve individuals with m/sTBI (age = 43.3 ± 9.5 yrs; >6 mo. post injury) and 12 healthy controls (CTLs) (age = 41.8 ± 8.3 yrs) were assessed while walking in a virtual subway station viewed in a head-mounted display. They performed a collision avoidance task with VRPs, as well as auditory-based cognitive tasks (pitch discrimination and auditory Stroop), both under single and dual-task conditions. Dual-task cost (DTC) for onset distance of trajectory deviation, minimum distance from the VRP, maximum lateral deviation, walking speed, gaze fixations and cognitive task accuracy were contrasted between groups using generalized estimating equations. RESULTS In contrast to CTLs who showed locomotor DTCs only, individuals with m/sTBI displayed both locomotor and cognitive DTCs. While both groups walked slower under dual-task conditions, only individuals with m/sTBI failed to modify their onset distance of trajectory deviation and maintained smaller minimum distances and smaller maximum lateral deviation compared to single-task walking. Both groups showed shorter gaze fixations on the approaching VRP under dual-task conditions, but this reduction was less pronounced in the individuals with m/sTBI. A reduction in cognitive task accuracy under dual-task conditions was found in the m/sTBI group only. CONCLUSION Individuals with m/sTBI present altered locomotor and gaze behaviours, as well as altered cognitive performances, when executing a collision avoidance task involving moving pedestrians in dual-task conditions. Potential mechanisms explaining those alterations are discussed. Present findings highlight the compromised complex walking abilities in individuals with m/sTBI who otherwise present a good locomotor recovery.
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Affiliation(s)
- Thiago de Aquino Costa Sousa
- School of Physical & Occupational Therapy, McGill University, Montreal, QC, Canada.
- Feil and Oberfeld Research Centre, Jewish Rehabilitation Hospital - CISSS Laval, Site of the Centre for Interdisciplinary Research in Rehabilitation of Greater Montreal (CRIR), 3205 Place Alton-Goldbloom, Laval, QC, H7V 1R2, Canada.
| | - Isabelle J Gagnon
- School of Physical & Occupational Therapy, McGill University, Montreal, QC, Canada
- Trauma/Child Development, Montreal Children's Hospital, Montreal, QC, Canada
| | - Karen Z H Li
- Department of Psychology, Concordia University, Montreal, QC, Canada
- Centre for Research in Human Development, Concordia University, Montreal, QC, Canada
- PERFORM Centre, Concordia University, Montreal, QC, Canada
| | - Bradford J McFadyen
- School of Rehabilitation Sciences, Université Laval, Quebec City, QC, Canada
- Centre for Interdisciplinary Research in Rehabilitation and Social Integration (Cirris), CIUSSS Capitale Nationale, Quebec City, QC, Canada
| | - Anouk Lamontagne
- School of Physical & Occupational Therapy, McGill University, Montreal, QC, Canada
- Feil and Oberfeld Research Centre, Jewish Rehabilitation Hospital - CISSS Laval, Site of the Centre for Interdisciplinary Research in Rehabilitation of Greater Montreal (CRIR), 3205 Place Alton-Goldbloom, Laval, QC, H7V 1R2, Canada
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Bhojwani TM, Lynch SD, Bühler MA, Lamontagne A. Impact of dual tasking on gaze behaviour and locomotor strategies adopted while circumventing virtual pedestrians during a collision avoidance task. Exp Brain Res 2022; 240:2633-2645. [PMID: 35980438 DOI: 10.1007/s00221-022-06427-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 07/25/2022] [Indexed: 11/25/2022]
Abstract
We investigated gaze behaviour and collision avoidance strategies in 16 healthy young individuals walking towards a goal while exposed to virtual pedestrians (VRPs) approaching from different directions (left, middle, right). This locomotor task and an auditory-based cognitive task were performed under single and dual-task conditions. Longer gaze fixation durations were observed on the approaching vs. other VRPs, with longer fixations devoted to the upper trunk and head compared to other body segments. Compared to other pedestrian approaches, the middle pedestrian received longer fixations and elicited faster walking speeds, larger onset distances of trajectory devitation and smaller obstacle clearances. Gaze and locomotor behaviours were similar between single and dual-task conditions but dual-task costs were observed for the cognitive task. The longer gaze fixations on approaching vs. other pedestrians suggest that enhanced visual attention is devoted to pedestrians posing a greater risk of collision. Likewise, longer gaze fixations for the middle pedestrians may be due to the greater collision risk entailed by this condition, and/or to the fact that this pedestrian was positioned in front of the end goal. Longer fixations on approaching VRPs' trunk and head may serve the purpose of anticipating their walking trajectory. Finally, the dual-task effects that were limited to the cognitive task suggest that healthy young adults prioritize the locomotor task and associated acquisition of visual information. The healthy patterns of visuomotor behaviour characterized in this study will serve as a basis for comparison to further understand defective collision avoidance strategies in patient populations.
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Affiliation(s)
- Trineta M Bhojwani
- School of Physical and Occupational Therapy, McGill University, Montreal, QC, Canada
- CRIR-Feil and Oberfeld Research Center, Jewish Rehabilitation Hospital, CISSS-Laval, 3205 Place Alton-Goldbloom, Laval, QC, H7V 1R2, Canada
| | - Sean D Lynch
- School of Physical and Occupational Therapy, McGill University, Montreal, QC, Canada
- CRIR-Feil and Oberfeld Research Center, Jewish Rehabilitation Hospital, CISSS-Laval, 3205 Place Alton-Goldbloom, Laval, QC, H7V 1R2, Canada
| | - Marco A Bühler
- School of Physical and Occupational Therapy, McGill University, Montreal, QC, Canada
- CRIR-Feil and Oberfeld Research Center, Jewish Rehabilitation Hospital, CISSS-Laval, 3205 Place Alton-Goldbloom, Laval, QC, H7V 1R2, Canada
| | - Anouk Lamontagne
- School of Physical and Occupational Therapy, McGill University, Montreal, QC, Canada.
- CRIR-Feil and Oberfeld Research Center, Jewish Rehabilitation Hospital, CISSS-Laval, 3205 Place Alton-Goldbloom, Laval, QC, H7V 1R2, Canada.
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Deblock-Bellamy A, Lamontagne A, McFadyen BJ, Ouellet MC, Blanchette AK. Virtual reality-based assessment of cognitive-locomotor interference in healthy young adults. J Neuroeng Rehabil 2021; 18:53. [PMID: 33752704 PMCID: PMC7983256 DOI: 10.1186/s12984-021-00834-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 02/03/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND A recent literature review emphasized the importance of assessing dual-task (DT) abilities with tasks that are representative of community ambulation. Assessing DT ability in real-life activities using standardized protocols remains difficult. Virtual reality (VR) may represent an interesting alternative enabling the exposure to different scenarios simulating community walking. To better understand dual-task abilities in everyday life activities, the aims of this study were (1) to assess locomotor and cognitive dual-task cost (DTC) during representative daily living activities, using VR, in healthy adults; and 2) to explore the influence of the nature and complexity of locomotor and cognitive tasks on DTC. METHODS Fifteen healthy young adults (24.9 ± 2.7 years old, 8 women) were recruited to walk in a virtual 100 m shopping mall corridor, while remembering a 5-item list (DT condition), using an omnidirectional platform and a VR headset. Two levels of difficulty were proposed for the locomotor task (with vs. without virtual agent avoidance) and for the cognitive task (with vs. without items modification). These tasks were also performed in single task (ST) condition. Locomotor and cognitive DTC were measured by comparing performances in ST and DT conditions. Locomotor performance was characterized using walking speed, walking fluidity, and minimal distance between the participant and the virtual agent during avoidance. Cognitive performance was assessed with the number of items correctly recalled. Presence of DTC were determined with one-sample Wilcoxon signed-rank tests. To explore the influence of the tasks' complexity and nature on DTC, a nonparametric two-way repeated measure ANOVA was performed. RESULTS No locomotor interference was measured for any of the outcomes. A cognitive DTC of 6.67% was measured (p = .017) while participants performed simultaneously both complex locomotor and cognitive tasks. A significant interaction between locomotor task complexity and cognitive task nature (p = .002) was identified on cognitive DTC. CONCLUSIONS In challenging locomotor and cognitive conditions, healthy young adults present DTC in cognitive accuracy, which was influenced by the locomotor task complexity task and the cognitive task nature. A similar VR-based protocol might be used to investigate DT abilities in older adults and individuals with a stroke.
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Affiliation(s)
- Anne Deblock-Bellamy
- Center for interdisciplinary research in rehabilitation and social integration (Cirris), CIUSSS de la Capitale-Nationale, 525 Boulevard Wilfrid-Hamel, Quebec City, QC G1M 2S8 Canada
- Faculty of Medicine, Universite Laval, 1050 Avenue de la Medecine, Quebec City, QC G1V 0A6 Canada
| | - Anouk Lamontagne
- Centre for Interdisciplinary Research in Rehabilitation of Greater Montreal (CRIR), Jewish Rehabilitation Hospital, CISSS de Laval, 3205 Alton-Goldbloom Place, Laval, QC H7V 1R2 Canada
- School of Physical and Occupational Therapy, McGill University, 3654 Prom Sir-William-Osler, Montreal, QC H3G 1Y5 Canada
| | - Bradford J. McFadyen
- Center for interdisciplinary research in rehabilitation and social integration (Cirris), CIUSSS de la Capitale-Nationale, 525 Boulevard Wilfrid-Hamel, Quebec City, QC G1M 2S8 Canada
- Faculty of Medicine, Universite Laval, 1050 Avenue de la Medecine, Quebec City, QC G1V 0A6 Canada
- Department of Rehabilitation, Universite Laval, 1050 Avenue de la Medecine, Quebec City, QC G1V 0A6 Canada
| | - Marie-Christine Ouellet
- Center for interdisciplinary research in rehabilitation and social integration (Cirris), CIUSSS de la Capitale-Nationale, 525 Boulevard Wilfrid-Hamel, Quebec City, QC G1M 2S8 Canada
- Faculty of Social Sciences, School of Psychology, Universite Laval, 2325 rue des Bibliothèques, Quebec City, QC G1V 0A6 Canada
| | - Andreanne K. Blanchette
- Center for interdisciplinary research in rehabilitation and social integration (Cirris), CIUSSS de la Capitale-Nationale, 525 Boulevard Wilfrid-Hamel, Quebec City, QC G1M 2S8 Canada
- Faculty of Medicine, Universite Laval, 1050 Avenue de la Medecine, Quebec City, QC G1V 0A6 Canada
- Department of Rehabilitation, Universite Laval, 1050 Avenue de la Medecine, Quebec City, QC G1V 0A6 Canada
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Keshner EA, Lamontagne A. The Untapped Potential of Virtual Reality in Rehabilitation of Balance and Gait in Neurological Disorders. FRONTIERS IN VIRTUAL REALITY 2021; 2:641650. [PMID: 33860281 PMCID: PMC8046008 DOI: 10.3389/frvir.2021.641650] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Dynamic systems theory transformed our understanding of motor control by recognizing the continual interaction between the organism and the environment. Movement could no longer be visualized simply as a response to a pattern of stimuli or as a demonstration of prior intent; movement is context dependent and is continuously reshaped by the ongoing dynamics of the world around us. Virtual reality is one methodological variable that allows us to control and manipulate that environmental context. A large body of literature exists to support the impact of visual flow, visual conditions, and visual perception on the planning and execution of movement. In rehabilitative practice, however, this technology has been employed mostly as a tool for motivation and enjoyment of physical exercise. The opportunity to modulate motor behavior through the parameters of the virtual world is often ignored in practice. In this article we present the results of experiments from our laboratories and from others demonstrating that presenting particular characteristics of the virtual world through different sensory modalities will modify balance and locomotor behavior. We will discuss how movement in the virtual world opens a window into the motor planning processes and informs us about the relative weighting of visual and somatosensory signals. Finally, we discuss how these findings should influence future treatment design.
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Affiliation(s)
- Emily A. Keshner
- Department of Health and Rehabilitation Sciences, Temple University, Philadelphia, PA, United States
- Correspondence: Emily A. Keshner,
| | - Anouk Lamontagne
- School of Physical and Occupational Therapy, McGill University, Montreal, QC, Canada
- Virtual Reality and Mobility Laboratory, CISSS Laval—Jewish Rehabilitation Hospital Site of the Centre for Interdisciplinary Research in Rehabilitation of Greater Montreal, Laval, QC, Canada
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Varas-Diaz G, Paralkar S, Wang S, Bhatt T. Kinematic Gait Adjustments to Virtual Environments on Different Surface Conditions: Do Treadmill and Over-Ground Walking Exhibit Different Adaptations to Passive Virtual Immersion? Rehabil Res Pract 2020; 2020:8901973. [PMID: 33414966 PMCID: PMC7769665 DOI: 10.1155/2020/8901973] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 11/17/2020] [Accepted: 12/10/2020] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The aim of this study was to examine the kinematic gait adjustments performed in response to passive and photorealistic virtual reality environment (VRE) demands during over-ground and treadmill walking conditions and determine whether the surface presentation order affects the gait adjustments in response to different VREs. METHODS Twenty young participants divided into two groups performed two virtual reality (VR) walking protocols which included two different VREs (snowy and crowded conditions). Group A performed the VR over-ground protocol (four natural walking (NW), seven VR snowy, and seven VR crowded trials) followed by the VR treadmill protocol (four NW, one VR snowy, and one VR crowded trials); Group B performed the VR treadmill protocol (four NW, seven VR snowy, and seven VR crowded trials) followed by the VR over-ground protocol (four NW, one VR snowy, and one VR crowded trials). Center of mass (COM) excursion angles and mediolateral (ML) COM excursions were analyzed and used as outcome measures. RESULTS Group A showed higher COM excursion angles and ML-COM excursion on over-ground VR trials compared to NW trials (p < 0.05), while Group B only showed kinematic changes for the crowded VRE compared to NW trials during the treadmill walking protocol (p < 0.05). Post over-ground exposure, Group A showed greater COM excursion angle and ML-COM excursions on VR trials compared to NW trials during the treadmill walking protocol (p < 0.05). Post treadmill exposure, Group B only showed higher COM excursion angles for the snowy VRE compared to NW trials during the over-ground walking protocol (p < 0.01). CONCLUSION Results showed that higher kinematic gait adjustments in response to VRE demands were observed during over-ground walking. Additionally, higher sensorimotor responses to VRE demands were observed when the VR protocol was first performed on the over-ground surface and followed by the treadmill walking condition (Group A) compared to the opposite (Group B).
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Affiliation(s)
- Gonzalo Varas-Diaz
- Department of Physical Therapy, University of Illinois at Chicago, Chicago IL, USA
- PhD Program in Rehabilitation Sciences, College of Applied Health Sciences, University of Illinois at Chicago, Chicago IL, USA
| | - Shivani Paralkar
- Department of Physical Therapy, University of Illinois at Chicago, Chicago IL, USA
| | - Shuaijie Wang
- Department of Physical Therapy, University of Illinois at Chicago, Chicago IL, USA
| | - Tanvi Bhatt
- Department of Physical Therapy, University of Illinois at Chicago, Chicago IL, USA
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Souza Silva W, McFadyen B, Kehayia E, Azevedo N, Fung J, Lamontagne A. Phone messages affect the detection of approaching pedestrians in healthy young and older adults immersed in a virtual community environment. PLoS One 2019; 14:e0217062. [PMID: 31141549 PMCID: PMC6541266 DOI: 10.1371/journal.pone.0217062] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 05/04/2019] [Indexed: 11/18/2022] Open
Abstract
Background Mobile phones are increasingly associated with accidents while walking. Little is known, however, about the impact of phone messaging on the actual perception of other pedestrians. This study aimed to investigate the extent to which the detection of approaching pedestrians is affected by the sensory modality (text or audio) of phone messages in young vs. older adults. Methods Eighteen healthy young (24 ± 2.9 years) and 15 older adults (68 ± 4.2 years) performed a phone message deciphering task, an obstacle detection task, and a dual-task condition combining both tasks. Participants were tested while seated and viewing a virtual subway station (VE) in a helmet mounted display. As they were passively moved within the VE one of three virtual pedestrians randomly approached them from the center (0°), right (+40°) or left (+40°). When present, phone message conditions were delivered at obstacle movement onset and presented either as (1) text messages on the screen of a virtual phone or (2) audio messages delivered through earphones. Participants were instructed to press a joystick button as soon as they detected the approaching virtual pedestrian and to report the message content at the end of the trials. Results Young and older participants showed delayed obstacle detection times with vs. without text messages. Older adults further showed reduced accuracy of message report for texts compared to audio messages. In both groups, audio messages yielded no difference in obstacle detection time or accuracy of message report compared to the no message condition. Conclusions Findings indicate that text messages prolong the detection of approaching pedestrians, suggesting that they compromise safe ambulation in community environments. Older adults, who show larger deteriorations on the obstacle detection and message deciphering tasks, may be at even greater risk of collision. Audio messages could be a safer alternative for on-the-go communication.
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Affiliation(s)
- Wagner Souza Silva
- School of Physical & Occupational Therapy, McGill University, Montreal, QC, Canada.,Feil and Oberfeld Research Center, Jewish Rehabilitation Hospital (CISSS-Laval), Research site of CRIR, Laval, QC, Canada
| | - Bradford McFadyen
- Department of Rehabilitation, Université Laval, Quebec City, QC, Canada.,Centre Interdisciplinaire de recherche en réadaptation et intégration sociale (CIUSSS-CN), Quebec City, QC, Canada
| | - Eva Kehayia
- School of Physical & Occupational Therapy, McGill University, Montreal, QC, Canada.,Feil and Oberfeld Research Center, Jewish Rehabilitation Hospital (CISSS-Laval), Research site of CRIR, Laval, QC, Canada
| | - Nancy Azevedo
- Feil and Oberfeld Research Center, Jewish Rehabilitation Hospital (CISSS-Laval), Research site of CRIR, Laval, QC, Canada
| | - Joyce Fung
- School of Physical & Occupational Therapy, McGill University, Montreal, QC, Canada.,Feil and Oberfeld Research Center, Jewish Rehabilitation Hospital (CISSS-Laval), Research site of CRIR, Laval, QC, Canada
| | - Anouk Lamontagne
- School of Physical & Occupational Therapy, McGill University, Montreal, QC, Canada.,Feil and Oberfeld Research Center, Jewish Rehabilitation Hospital (CISSS-Laval), Research site of CRIR, Laval, QC, Canada
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