ENSEMBLE NEURAL CODING OF PLACE AND DIRECTION IN ZERO-G

描述：（改编自申请人的摘要。）最近 神经生理学和行为实验强烈地表明， 快速有效的空间定位能力是基于 主要是一组高阶神经元之间的相互作用， 传输空间位置的表示和广泛的网络 新皮层和皮层下神经元的活动， 角速度信息来计算和发送信号 反映了动物头部方位的方位角分量， 相对于惯性参考框架。这样的系统是理想的。 适用于计算相关的行为轨迹， 地球环境，首先是因为它使空间成为 内部表示和存储经济作为一组地标- 矢量，第二，因为它使轨迹计算 通过矢量减法来执行。 后一种能力 允许快速计算新的，直接的轨迹， 理想目标。很明显，这个定位系统 基于相对于局部重力的方位角信息 菲尔德认为，在低重力或零重力条件下， situations.目前关于神经实验室使命的建议旨在 在行为自由的啮齿动物身上进行神经生理学实验， 解决这个关键系统如何运行的问题， 适应低重力条件。 该实验室开发的方法能够同时 大量参与空间神经元的记录 定位系统，并使相同的神经元合奏， 研究了长达数周的时间。 这项技术将 最大化相关神经生理学数据的数量， 从少数啮齿动物中获得（2-4）。 调查人员 实际上，我希望能够获得隔离良好的装置 记录了多达1000个新皮层，丘脑和顶盖 神经元在一个单一的使命的过程中，并研究合奏 在任何给定的记录实验中，50-150个细胞的相互作用。他们 我还建议协助和合作，与其他研究小组， 使用相同的技术来解决其他重要问题， 与航天飞行有关的神经生理学问题，包括 运动控制和感觉运动整合的可能变化， 睡眠-觉醒周期和自主控制。

DESCRIPTION: (Adapted from the Applicant's Abstract.) Recent neurophysiological and behavioral experiments strongly suggest that the capacity for rapid and effective spatial orientation is based primarily on the interaction between a set of high-order neurons that transmit a representation of spatial location, and an extensive network of neocortical and subcortical neurons which use vestibular, angular-velocity information to compute and transmit a signal reflecting the azimuthal component of the animal's head orientation, relative to an inertial reference framework. Such a system is ideally suited for the computation of relevant behavioral trajectories in an earth-bound environment, first because it enables space to be internally represented and stored economically as a set of landmark- vectors, and second, because it enables the trajectory computation to be carried out by vector subtraction. The latter capacity permits the rapid calculation of novel, direct trajectories to a desired target. Clearly, the fact that this orientation system is based on azimuthal information with respect to the local gravitational field suggests that problems may develop in low or zero-gravity situations. The present proposal for the NeuroLab mission aims to use neurophysiological experiments in freely behaving rodents to address the question of how this crucial system performs and adapts to low gravity conditions. Methods developed in this laboratory have enabled the simultaneous recording from large numbers of neurons involved in the spatial orientation system and which enable the same neuronal ensembles to be studied over periods of up to several weeks. This technology will maximize the amount of relevant neurophysiological data that can be obtained from a small number of rodents (2-4). The investigators realistically expect to be able to obtain well isolated unit recordings from as many as 1000 neocortical, thalamic, and tectal neurons over the course of a single mission, and to study the ensemble interactions of 50-150 cells in any given recording experiment. They also propose to assist and collaborate with other research groups in employing the same technology to address other important neurophysiological questions of relevance to space flight, including possible changes in motor control and sensori-motor integration, sleep-waking cycles, and autonomic control.