Audio Based Navigation in the Blind

我们提出了一种现场和实验室相结合的方法，通过虚拟导航来研究盲人的认知空间映射，并评估在真实世界导航任务中获得的空间知识的迁移。导航性能的培训和评估将通过一个以用户为中心的、基于计算机的导航软件平台进行，该平台称为基于听觉的环境模拟器(ABES)。该软件旨在通过身临其境的虚拟导航向盲人用户介绍不熟悉的环境，从而帮助进行定向和行动(O&M)培训。使用听觉光谱线索，用户可以学习构建他们物理环境的认知空间地图。在这项研究中，参与者将与该软件互动，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，我们将比较使用该软件的早期和晚期盲人在两种不同模式下的学习和空间认知地图发展：1)由辅导员引导预先确定的路线的定向导航；2)以探索主题视频游戏为借口的自我定向(或“开放发现”)导航。然后，将通过在实际物理环境中执行的导航任务来评估转换所获得的空间信息的能力。在这项研究的第二阶段，我们将研究与空间导航相关的神经。使用功能磁共振成像(FMRI)，与导航相关的神经网络将在有视力的人中进行评估，并与早期和晚期盲人进行比较，并作为随时间推移整体行为表现的函数。其次，将通过使用经颅磁刺激(TMS)的可逆性皮质破坏来评估已识别的皮质区域的功能贡献。这项研究的结果将1)为我们理解与导航相关的神经机制提供新的见解，2)开发新的盲人定向和导航训练方法。

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.