Audio Based Navigation in the Blind

我们提出了一种结合现场和实验室的方法，通过虚拟导航研究盲人的认知空间映射，并评估在现实世界的导航任务中获得的空间知识的转移。导航性能的培训和评估将通过一个以用户为中心、基于计算机的导航软件平台进行，该平台被称为基于听觉的环境模拟器（AbES）。该软件的开发目的是通过沉浸式虚拟导航将盲人用户引入一个陌生的环境，以辅助定向和移动（O&M）培训。使用听觉谱线索，用户学会了建立一个物理环境的认知空间地图。在这项研究中，参与者将与软件进行交互，并在代表实际物理空间的模拟虚拟环境中导航。在研究的第一阶段，我们将比较早期和晚期盲人在两种不同模式下使用该软件的学习和空间认知地图的发展：1)由引导者引导的预先确定路线的定向导航，2)在探索主题视频游戏的前提下自主（或“开放发现”）导航。翻译获得的空间信息的能力将在实际物理环境中进行导航任务进行评估。在研究的第二阶段，我们将研究与空间导航相关的神经关联。使用功能性磁成像（fMRI），将评估视力正常的人与早期和晚期失明的人相比，与导航相关的神经网络，以及随着时间的推移，作为整体行为表现的功能。其次，通过使用经颅磁刺激（TMS）进行可逆性皮质破坏来评估识别的皮质区域的功能贡献。这项研究的结果将为我们理解与导航相关的神经机制提供新的见解，并为盲人的定向和导航训练提供新的方法。

We propose a combined field and laboratory approach investigating cognitive spatial mapping in the blind through virtual navigation and assessing the transference of acquired spatial knowledge in a real-world navigation task. Training and evaluation of navigation performance will be carried out with a user-centered, computer-based navigation software platform called Auditory-based Environment Simulator (AbES). This software was developed to assist in orientation and mobility (O&M) training by introducing a blind user to an unfamiliar environment through immersive virtual navigation. Using auditory spectral cues, a user learns to build a cognitive spatial map of their physical surroundings. In this study, participants will interact with the software and navigate through a simulated virtual environment that represents an actual physical space. In a first phase of the study, we will compare learning and spatial cognitive map development in early and late blind individuals using the software in two different modes: 1) directed navigation of pre-determined routes guided by a facilitator and 2) self-directed (or "open discovery") navigation under the pretext of an exploration-theme video game. The ability to translate acquired spatial information will then be assessed with navigating tasks carried out in the actual physical environment. In a second phase of the study, we will investigate the neural correlates associated with spatial navigation. Using functional magnetic imaging (fMRI), neural networks associated with navigation will be assessed in sighted compared to early and late blind individuals and as a function of overall behavioral performance over time. Secondly, the functional contribution of identified cortical areas will be assessed by reversible cortical disruption using transcranial magnetic stimulation (TMS). The results of this study will 1) contribute new insights towards our understanding of the neural mechanisms associated with navigation and 2) develop novel approaches for orientation and navigation training in the blind.