Behavioural and neuroimaging approaches to understanding the neurocognitive basis of real-world spatial navigation

对我们的空间环境的记忆对日常生活至关重要。我们依靠空间记忆在家里和世界上四处走动，定位物体和建筑物；没有空间记忆，我们真的会迷失方向。这项建议关注的是当我们获得在室内和室外环境中导航的经验时，我们如何在记忆中表示大规模的室内和室外环境。形成对新环境的空间记忆依赖于海马体，海马体是一种位于颞叶深处的大脑结构，随着我们年龄的增长而变化。一旦我们对环境变得非常熟悉，在海马体受损后，该环境的空间记忆就会保留下来，取而代之的是依赖于其他大脑结构，如顶叶皮质。然而，高度详细和精确的空间记忆仍然依赖于海马体。这一结果模式表明，我们在海马体外形成了一个“要点”或“图式”，它保留了环境的几何形状，但不保留了它的视觉特征(例如，颜色、树木)，作为未来遇到相同或相似环境的模板。测试这一想法的一种方法是确定修改新学习或非常熟悉的环境的视觉特征和/或几何图形对寻路的影响程度。这些影响也可能体现在观看行为和海马体内外活动的变化上。我们将结合眼睛跟踪和功能磁共振成像(FMRI)与虚拟现实(VR)来表征年轻人和老年人的导航，因为衰老与海马体结构和功能的变化有关。参与者将收到一系列虚拟寻路任务，这些任务在约克大学和贝克雷斯特医院校园的详细3D模型中实施，可以使用Unity 3D以第一或第三人称实时渲染和可视化。这将使我们能够在室外和室内环境中为参与者提供完全身临其境的寻路体验，并选择性地操纵特定功能来评估寻路效果。我们将检查任务执行期间海马体内外的活动，并将其与自我报告的导航能力和导航策略偏好进行比较。加拿大在认知神经科学领域有着丰富的历史，被认为是记忆研究的国际领先者。重要的是，通过对学生进行专门培训，发展基本理论和有效应用创新技术，如用于检查大脑功能的功能磁共振成像，来保持这一地位。这项研究的发现将有助于更好地理解空间记忆的认知构成，它与非空间记忆的关系，以及它在人脑中的表现方式。

Memory of our spatial environment is crucial for daily life. We rely on spatial memory to get around at home and in the world, and to locate objects and buildings; without spatial memory, we literally would be lost. This proposal is concerned with how we represent large-scale indoor and outdoor environments in memory as we gain experience navigating within them. Forming spatial memories of new environments depends on the hippocampus, a brain structure deep in the temporal lobes that changes as we get older. Once we become very familiar with an environment, spatial memory of that environment is preserved after hippocampal damage and instead relies on other brain structures, such as parietal cortex. However, spatial memories that are highly detailed and precise continue to depend on the hippocampus. This pattern of results suggests that we form a "gist" or "schema" outside of the hippocampus that preserves the geometry of an environment, but not its visual features (e.g., colours, trees), serving as a template for future encounters with the same or similar environments. One way to test this idea is to determine the extent to which modifying visual features and/or geometry of a newly learned or highly familiar environment affects wayfinding. These effects might also be seen in changes to viewing behaviour and to activity within and outside of the hippocampus. We will combine eye tracking and functional magnetic resonance imaging (fMRI) with virtual reality (VR) to characterize navigation in young adults and older adults, as aging is associated with changes to hippocampal structure and function. Participants will receive a series of virtual wayfinding tasks, implemented in detailed 3D models of York University and Baycrest Hospital campuses that can be rendered and visualized in 1st-or 3rd-person in real-time using Unity 3D. This will allow us to provide participants with a fully immersive experience during wayfinding in both outdoor and indoor environments, and to selectively manipulate specific features to assess the effects on wayfinding. We will examine activity within and outside of the hippocampus during task performance and compare performance to self-reported navigation ability and navigation strategy preference. Canada has a rich history in the area of cognitive neuroscience and is regarded as an international leader in memory research. It is important to maintain this status through the specialized training of students in developing basic theory and effective applications of innovative technologies such as fMRI for examining brain function. Findings from this research will lead to a greater understanding of the cognitive makeup of spatial memory, how it relates to non-spatial memory, and how it is represented in the human brain.