The Role of Place and Grid Cells in Human Spatial and Non Spatial Memory

项目摘要 空间导航和记忆是动物和人类生活的重要方面。为了确定大脑是如何 支持这些过程，我们的实验研究如何特定类型的空间和非空间知识 由人类内侧颞叶中的单个神经元和神经元群体的活动表示。 以前，我们和其他人表明，空间知识是由“地点”和“网格单元”网络支持的， 其中每一个都通过在各个位置和组处激活来表示人在环境中的位置 的位置，分别。虽然人类的内侧颞叶也被认为是记忆的关键， 想象力，预测和规划，空间细胞类型是否以及如何也支持这些复杂的形式， 认知是未知的。在这里，我们将测试的假设，地方和网格状的发射模式，以及其他 海马系统中的细胞类型，支持更复杂的空间和 非空间信息超出了人类这些不同的，相互关联的方面的神经编码的位置 认知.我们通过直接记录人类海马和内嗅神经元来研究这个问题。 神经外科癫痫患者执行计算机虚拟现实任务的网络。我们的目标1 项目，我们将研究是否内侧颞叶神经元放电模式，包括地方和网格样 发射，超越编码空间信息，以代表每个环境的“认知地图”， 表示连接的位置和路径的集合以及它们如何被奖励。在目标2中，我们检查 地点和网格单元在表示多尺度信息（包括大尺度地理）中的作用。在Aim中 3.我们探讨人类位置细胞的活动是否以某种方式代表想象和观察的位置， 类似于在主动导航期间存在的活动。最后，在目标4中，我们测量了人类的“时间细胞”，并测试了 情景记忆中时间细胞的活动是否与位置和网格细胞的性质相似， 导航我们提出的研究可能会对核心神经元的反应产生根本性的见解 以及空间和非空间记忆和认知的计算机制。

Project Summary Spatial navigation and memory are critical aspects of life for animals and humans. To identify how the brain supports these processes, our experiments examine how specific types of spatial and non-spatial knowledge are represented by the activity of single neurons and neuronal populations in the human medial temporal lobe. Previously, we and others showed that spatial knowledge is supported by networks of “place” and “grid cells,” each of which represent a person’s location in an environment by activating at individual locations and groups of locations, respectively. Though the human medial temporal lobe is also believed to be critical for memory, imagination, prediction, and planning, whether and how spatial cell types also support these complex forms of cognition is unknown. Here we will test the hypothesis that place- and grid-like firing patterns, as well as other cell types in the hippocampal system, support the neuronal representation of more complex spatial and non-spatial information beyond the neural coding of location for these diverse, inter-related aspects of human cognition. We examine this issue by conducting direct recordings of the human hippocampal and entorhinal network from neurosurgical epilepsy patients performing computerized virtual-reality tasks. In Aim 1 of our project we will examine whether medial temporal lobe neuronal firing patterns, including place- and grid-like firing, go beyond encoding spatial information to represent a “cognitive map” of each environment that represents which sets of locations and paths are connected and how they are rewarded. In Aim 2, we examine the role of place and grid cells in representing multiscale information, including large-scale geography. In Aim 3, we probe whether the activity of human place cells represent imagined and viewed locations in a manner similar to the activity present during active navigation. Finally, in Aim 4 we measure human “time cells” and test whether the activity of time cells in episodic memory are similar to the properties of place and grid cells during navigation. Our proposed studies are likely to create fundamental insights into the core neuronal responses and computational mechanisms that underlie both spatial and non-spatial memory and cognition.