School of Physical & Occupational Therapy, McGill University, H3G 1Y5 Montreal, QC, Canada; Feil and Oberfeld Research Centre, Jewish Rehabilitation Hospital, Research site of CRIR, 3205, place Alton Goldbloom, H7V 1R Laval, QC, Canada.
Ann Phys Rehabil Med. 2018 Jul;61(4):197-206. doi: 10.1016/j.rehab.2017.05.002. Epub 2017 Jun 9.
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.
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.
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.
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.
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.
视觉空间忽略（VSN）会损害脑卒中患者的运动朝向控制，这可能会影响他们在行走时安全避开移动物体的能力。
我们旨在比较 VSN+和 VSN-脑卒中患者在回避来自不同方向接近的障碍物并重新朝向最终目标时，朝向和头部在空间中的变化。
脑卒中伴有 VSN（VSN+）和不伴有 VSN（VSN-）的参与者在虚拟环境中行走，以避开向病变对侧、正面或病变同侧接近的障碍物。比较了各组和障碍物方向的障碍物回避（朝向变化开始、最大横移偏差）和目标对准（相对于目标的朝向和头部旋转误差）的测量值。
共有 26 名右侧脑卒中参与者（13 名 VSN+和 13 名 VSN-；24 名男性；平均年龄 60.3 岁，范围 48 至 72 岁）。与 VSN-参与者（38%）相比，VSN+参与者（75%）与病变对侧和正面障碍物碰撞的比例更大。对于 VSN-参与者，向障碍物相同侧偏离是避免对角线障碍物的安全策略，而向相反侧偏离则偶尔会导致碰撞。VSN+参与者向病变同侧偏离，对病变同侧和病变对侧障碍物分别采用同侧和对侧策略。总的来说，与 VSN-参与者相比，VSN+参与者的起始朝向变化距离更大，最大横移偏差更小，目标对准误差更大。
VSN 引起的病变侧偏向会影响对障碍物的朝向调节，加上采用“风险更高”的策略，导致 VSN 脑卒中幸存者碰撞次数增加，目标导向行走能力较差。未来的研究应集中于为该人群的复杂运动任务（如回避障碍物）开发评估和训练工具。
