Healthy young adults implement distinctive avoidance strategies while walking and circumventing virtual human vs. non-human obstacles in a virtual environment
Healthy young adults implement distinctive avoidance strategies while walking and circumventing virtual human vs. non-human obstacles in a virtual environment
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DOI：
10.1016/j.gaitpost.2018.01.028
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发表时间：
2018-03-01
期刊：
影响因子：
2.4
通讯作者：
Lamontagne, Anouk
中科院分区：
文献类型：
--
作者：
Silva, Wagner Souza;Aravind, Gayatri;Lamontagne, Anouk
本研究探讨了圆柱体、虚拟人和有脚步声的虚拟人三种障碍物对健康青年规避策略的影响。16名年龄为25.2 +/- 2.5岁（平均值+/-1 SD）的参与者在地上行走并通过头盔显示器查看虚拟房间时接受了测试。当参与者走向远处空间中的固定目标时，他们避开了从右侧（+40度），左侧（-40度）或正面（0度）接近的障碍物（圆柱体或虚拟人）。避障策略的特点是使用的位置和方向的头部。重复混合模型分析显示，与圆柱体相比，在避免虚拟人的同时，最小距离较小（p=0.007）。与不提供声音时相比，添加到虚拟人的脚步声没有修改（p=0.2）最小距离。回避策略的发作时间在不同条件下相似（p=0.06）。结果表明，障碍物的性质（类人与非人类对象）的事项，可以修改回避策略。较小的障碍物清除响应虚拟人可能反映了一个不太保守的避免策略的使用，由于障碍物的相似性，行人和召回的日常运动中使用的策略。缺乏影响的脚步声支持的事实，避障主要依赖于视觉线索和“逆效应”的原则，即多感觉神经元的多模态刺激的反应变得较弱时，单峰的感觉刺激（视觉）是强的。目前的研究结果应考虑到优化生态有效性的VR为基础的避障范式用于研究和康复。
This study examines how three types of obstacles (cylinder, virtual human and virtual human with footstep sounds) affect circumvention strategies of healthy young adults. Sixteen participants aged 25.2 +/- 2.5 years (mean +/- 1SD) were tested while walking overground and viewing a virtual room through a helmet mounted display. As participants walked towards a stationary target in the far space, they avoided an obstacle (cylinder or virtual human) approaching either from the right (+40 degrees), left (-40 degrees) or head-on (0 degrees). Obstacle avoidance strategies were characterized using the position and orientation of the head. Repeated mixed model analysis showed smaller minimal distances (p=0.007) while avoiding virtual humans as compared to cylinders. Footstep sounds added to virtual humans did not modify (p=0.2) minimal distances compared to when no sound was provided. Onset times of avoidance strategies were similar across conditions (p=0.06). Results indicate that the nature of the obstacle (human-like vs. non-human object) matters and can modify avoidance strategies. Smaller obstacle clearances in response to virtual humans may reflect the use of a less conservative avoidance strategy, due to a resemblance of obstacles to pedestrians and a recall of strategies used in daily locomotion. The lack of influence of footstep sounds supports the fact that obstacle avoidance primarily relies on visual cues and the principle of 'inverse effectiveness' whereby multisensory neurons' response to multimodal stimuli becomes weaker when the unimodal sensory stimulus (vision) is strong. Present findings should be taken into consideration to optimize the ecological validity of VR-based obstacle avoidance paradigms used in research and rehabilitation.