少即是多：步态同步乳突振动用于舒适保持的重新定向行走

文献信息

中文摘要

重新定向行走（RDW）利用自我运动感知的容差，使用户能够在有限的物理空间内探索大型虚拟环境。既往研究表明，通过电刺激或持续振动刺激增加前庭噪声可以提高重定向检测阈值（DTs）。然而，电刺激可能损害步态稳定性，而持续振动可引起不适。因此，需要能够更好地平衡有效性与用户舒适度的替代方法。为解决这一问题，本研究探讨将前庭振动与步态事件在时间上同步是否能够在保持舒适度和运动稳定性的同时增强重定向耐受性。三十六名参与者在三种条件下执行基于曲率的RDW任务：无振动、持续振动和步态同步振动。DTs采用二选一强制选择范式结合心理测量建模进行估计。还评估了主观不适、模拟器 sickness 和临场感，并通过无标记运动分析获得客观步态稳定性指标。结果显示，与无振动基线相比，两种振动条件均显著增加了曲率DTs。值得注意的是，步态同步振动产生的曲率DTs与持续振动相当，同时显著减少了不适。此外，模拟器 sickness、临场感和无标记步态分析在各条件间均无显著差异。这些发现表明，步态同步前庭振动增强了重定向耐受性，同时保持了舒适度和步态稳定性。

英文摘要

Redirected Walking (RDW) enables users to explore large virtual environments within limited physical spaces by exploiting tolerances in self-motion perception. Previous research has shown that adding vestibular noise through electrical or continuous vibratory stimulation can increase redirection detection thresholds (DTs). However, electrical stimulation may compromise gait stability, while continuous vibration can induce discomfort. Therefore, alternative approaches that better balance effectiveness and user comfort are needed. To address this issue, this study investigates whether temporally synchronizing vestibular vibration with gait events can enhance redirection tolerance while preserving comfort and locomotor stability. Thirty-six participants performed a curvature-based RDW task under three conditions: no vibration, continuous vibration, and stepsynchronized vibration. DTs were estimated using a two-alternative forced-choice paradigm combined with psychometric modeling. Subjective discomfort, simulator sickness, and presence were also assessed, alongside objective gait stability measures obtained through markerless motion analysis. Results showed that both vibration conditions significantly increased curvature DTs compared with the no-vibration baseline. Notably, step-synchronized vibration produced curvature DTs comparable to continuous vibration while significantly reducing discomfort. Furthermore, simulator sickness, presence, and markerless gait analysis showed no significant differences across conditions. These findings suggest that gait-synchronized vestibular vibration enhances redirection tolerance while preserving comfort and gait stability.