Interrogating the Dynamic Neural Computation of the Sense of Direction

质疑方向感的动态神经计算

基本信息

批准号：
10752171
负责人：
Oliver Riley Stanley
金额：
$ 4.77万
依托单位：
JOHNS HOPKINS UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2023
资助国家：
美国
起止时间：
2023-05-15 至 2025-05-14
项目状态：
未结题

项目摘要

PROJECT SUMMARY / ABSTRACT Navigating dynamic environments to avoid danger and locate the necessities of life relies critically on animals keeping track of their own position and heading within the world, which cannot be sensed directly but instead must be inferred by integrating many streams of information, including vestibular, proprioceptive, and visual. Because directional heading has a straightforward mathematical definition (i.e., horizon and azimuth angles), the sense of direction represents fertile ground for quantitative study of multisensory integration and population coding in numerous areas of the brain. In particular, electrophysiological experiments studying the brain's representation of the body's spatial relationship to the environment have described a class of neurons referred to as head direction (HD) cells, which each fire when an animal is facing a specific preferred direction. The prevailing model for the generation of the signal encoded by these cells assumes that information about angular head velocity from the vestibular system drives activity changes in reciprocally-connected brainstem areas, the dorsal tegmental and lateral mammillary nuclei. These areas are modeled as a ring attractor network, which can maintain a stable pattern of activity due to excitatory connections between neurons with similar preferred directions and inhibition between neurons with opposing preferred directions. However, the main projection from the vestibular nuclei to the network of brain areas containing HD cells is via the nucleus prepositus, which principally encodes eye-related rather than head-related information. Thus, it seems likely that eye-related information plays a substantial role in the generation of the HD signal. The summation of head-in-world direction with eye-in-head direction defines gaze direction. We thus hypothesize that the "head direction" network in actuality primarily encodes gaze direction. In order to investigate this hypothesis, I will record from multiple points of the HD network in rhesus macaques during both passive motion and active locomotion using high-density neural probes while simultaneously tracking eye, body, and head movements. By analyzing eye, head, and limb movements in conjunction with recordings from the HD system at multiple stages of information processing, and in particular by recording from large numbers of neurons at multiple locations simultaneously, this project will provide new insights into fundamental questions about how the brain represents the world and the body's relationship to it.

项目概要/摘要在动态环境中航行以避免危险并找到生活必需品很大程度上依赖于动物跟踪自己在世界中的位置和前进方向，这是无法直接感知的，但可以必须通过整合许多信息流来推断，包括前庭、本体感觉和视觉。由于定向航向具有简单的数学定义（即水平角和方位角），方向感为多感官整合和群体的定量研究提供了肥沃的土壤在大脑的许多区域进行编码。特别是，研究大脑对身体空间的表征的电生理学实验与环境的关系描述了一类被称为头部方向（HD）细胞的神经元，当动物面向特定的首选方向时，每次都会触发。这一代人的流行模式这些细胞编码的信号假设来自前庭的角速度信息系统驱动相互连接的脑干区域、背侧被盖区和外侧被盖区的活动变化乳头核。这些区域被建模为环形吸引子网络，可以保持稳定的模式由于具有相似偏好方向和抑制的神经元之间的兴奋性连接而导致的活动具有相反首选方向的神经元之间。然而，从前庭核团到含有 HD 细胞的大脑区域网络通过前核，主要编码与眼睛相关的信息而不是与头部相关的信息。因此，与眼睛相关的信息似乎发挥着重要作用在高清信号的生成中发挥着重要作用。头在世界方向与眼在头方向的总和定义了注视方向。我们因此假设“头部方向”网络实际上主要编码注视方向。为了为了研究这个假设，我将从恒河猴的高清网络的多个点进行记录使用高密度神经探针进行被动运动和主动运动，同时跟踪眼睛，身体和头部的动作。通过结合记录来分析眼睛、头部和四肢的运动高清系统在信息处理的多个阶段，特别是通过大量记录同时，该项目将为多个位置的神经元提供新的见解关于大脑如何代表世界以及身体与世界的关系的问题。