Article

Visuospatial neglect (VSN) impairs the control of locomotor heading
in post-stroke individuals, which may affect their ability to safely avoid moving
objects while walking. OBJECTIVE: We aimed to compare VSN+ and VSN- stroke
individuals in terms of changes in heading and head orientation in space while
avoiding obstacles approaching from different directions and reorienting toward
the final target. METHODS: Stroke participants with VSN (VSN+) and without VSN
(VSN-) walked in a virtual environment avoiding obstacles that approached
contralesionally, head-on or ipsilesionally. Measures of obstacle avoidance
(onset-of-heading change, maximum mediolateral deviation) and target alignment
(heading and head-rotation errors with respect to target) were compared across
groups and obstacle directions. RESULTS: In total, 26 participants with
right-hemisphere stroke participated (13 VSN+ and 13 VSN-; 24 males; mean age
60.3 years, range 48 to 72 years). A larger proportion of VSN+ (75%) than VSN-
(38%) participants collided with contralesional and head-on obstacles. For VSN-
participants, deviating to the same side as the obstacle was a safe strategy to
avoid diagonal obstacles and deviating to the opposite-side led to occasional
collisions. VSN+ participants deviated ipsilesionally, displaying same-side and
opposite-side strategies for ipsilesional and contralesional obstacles,
respectively. Overall, VSN+ participants showed greater distances at
onset-of-heading change, smaller maximum mediolateral deviation and larger errors
in target alignment as compared with VSN- participants. CONCLUSION: The
ipsilesional bias arising from VSN influences the modulation of heading in
response to obstacles and, along with the adoption of the "riskier" strategies,
contribute to the higher number colliders and poor goal-directed walking
abilities in stroke survivors with VSN. Future research should focus on
developing assessment and training tools for complex locomotor tasks such as
obstacle avoidance in this population.
CI - Copyright (c) 2017 Elsevier Masson SAS. All rights reserved.

Langue : ANGLAIS