Vestibular signal integration in hippocampal place cells

项目摘要/摘要 以前对啮齿动物的研究已经确定了参与导航功能的五种主要细胞类型， 包括头部方向(HD)、位置、栅格、边界单元格和速度单元格。海马区(HP)细胞 据报道，在积极探索的过程中对动物的空间位置进行了编码。然而，最近的研究使用 头部或身体固定的虚拟现实环境报告称，HP空间调谐减少， 西塔节奏。我们推测，这些对幽门螺杆菌细胞功能的影响源于视觉和细胞功能之间的冲突。 运动提示和缺乏适当的前庭提示来发出主动动作的信号。当前项目是 旨在直接测试HP细胞用来形成和维持空间的前庭运动信息的类型 位置信息。在检查惠普细胞时，将同时使用真实世界和虚拟现实环境 使用我们构建的独特的虚拟现实系统，该系统安装在嵌入在 一个六自由度的六足动物。特定目标1将确定HP细胞的空间调谐是否需要前庭运动信号 通过提供受制于视觉运动提示的旋转和直线运动轮廓 动物在虚拟环境中的运动。具体目标2将决定前庭旋转和 直线运动信号分别影响HP细胞功能。我们假设前庭旋转信号是 Hp细胞的空间调谐和前庭直线运动提示是theta节律幅度所必需的 和频率。该项目代表了我们实验室的一个新的研究领域，因此它适合于 探索性/开发性R21应用程序。我们的长期目标是了解前庭机制 为空间导航做出贡献。

PROJECT SUMMARY/ABSTRACT Previous studies in rodents have identified five major cell types that are involved in navigation functions, including head direction (HD), place, grid, border cells, and speed cells. Hippocampal Place (HP) cells are reported to encode the spatial location of the animal during active exploration. However, recent studies using head or body fixed virtual reality environments have reported a reduction in HP spatial tuning and a loss of theta rhythm. We hypothesize that these effects upon HP cell function derive from a conflict between visual- locomotor cues and a lack of appropriate vestibular cues to signal active motion. The current project is designed to directly test the type of vestibular motion information used by HP cells to form and maintain spatial location information. Both real world and virtual reality environments will be used while examining HP cell function using a unique virtual reality system we have built that is mounted onto a rotatory motor embedded in a 6DOF hexapod. Specific Aim 1 will determine if HP cells spatial tuning requires vestibular motion signals congruent to visual-locomotion cues by delivering rotational and linear motion profiles that are slaved to the animal's locomotion in the virtual environment. Specific Aim 2 will determine how vestibular rotational and linear motion signals separately affect HP cell function. We hypothesize that vestibular rotational signals are necessary for HP cell spatial tuning and vestibular linear motion cues are necessary for theta rhythm amplitude and frequency. The project represents a new area of research for our laboratory, thus it is appropriate for an exploratory/development R21 application. Our long-term goal is to understand the how vestibular mechanisms contribute to spatial navigation.