INPUT-OUTPUT PROPERTIES OF A MAPPED SENSORY SYSTEM

映射传感系统的输入输出属性

• 批准号: 6186074
• 负责人: JOHN Pratt MILLER
• 金额: $ 14.59万
• 依托单位: MONTANA STATE UNIVERSITY - BOZEMAN
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-04-01 至 2002-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6186074
• 关键词: Orthoptera; afferent nerve; biological models; computational neuroscience; computer simulation; electrical measurement; electrodes; electrophysiology; interneurons; mechanoreceptors; neural information processing; sensory mechanism; sensory receptors; sensory thresholds; stimulus /response

The overall goal of this research is to determine how the neurons in a relatively complex, topographically-mapped sensory system extract information about stimuli and encode that information in their spike trains. The specific aims of the studies are: 1) to determine what parameters of sensory stimuli are encoded in the spike trains of the sensory receptors and projecting interneurons in this system; 2) to determine the accuracy with which that information is encoded; 3) to determine how the information is encoded within different aspects of the spike train patterns; 4) to examine the mechanisms through which the observed coding scheme is actually implemented within this neural network, 5) to determine the extent to which the observed accuracy approaches the theoretical maximum limits, given the constraints imposed by the "physics" of the stimulus environment, and 6) to examine the principles through which features of the system have been optimized to meet those constraints. The preparation to be studied is the cercal sensory system of the cricket. This system mediates the detection and analysis of low velocity air currents in the animal's immediate environment. All relevant sensory information is carried to higher centers by only ten pairs of primary sensory interneurons. All of these output units are identified, and all will be monitored simultaneously with extracellular electrodes. The first three goals listed above will be achieved by carrying out several types of electrophysiological input/output analyses, primarily at a systems level. Principles of information theory will be applied to the data to obtain quantitative, model-independent measures of the amount of information encoded within the spike trains of sensory receptors and primary sensory interneurons. The fourth goal will be achieved through further electrophysiological measurements, the results of which will be embodied in a physiology-based model of the system. The model will be refined, and its validity tested, on the basis of information theoretic analyses similar to the ones that were carried out on the real system. The fifth goal will be achieved through calculations of the constraints on the system's performance imposed by thermal noise in the air current environment. The sixth goal will be achieved through computer simulations of mechanoreceptor and interneuron characteristics. The studies will elucidate general principles related to optimal signal processing within sensory systems and may suggest general algorithms for efficient coding of information by ensembles of neurons.

这项研究的总体目标是确定神经元是如何 相对复杂、地形图绘制的感觉系统摘录 关于刺激信息，并在它们的脉冲中编码该信息 火车。这些研究的具体目的是：1)确定 感觉刺激的参数被编码在脉冲序列中 该系统的感觉受体和投射中间神经元；2) 确定该信息编码的准确性；3) 确定信息在不同方面的编码方式。 刺激性训练模式；4)研究 观察到的编码方案实际上是在该神经内实现的 网络，5)以确定观测精度的程度 接近理论上的最大限制，考虑到施加的限制 通过刺激环境的“物理学”，以及6)检查 对系统功能进行优化以达到以下目的的原则 满足这些限制。 拟研究的制剂为颈椎感觉系统。 板球。该系统实现了低速的检测和分析。 动物周围环境中的气流。所有相关的感官 信息只由十对初级中心传送到更高的中心 感觉中间神经元。所有这些输出单元都已确定，并且所有 将与细胞外电极同时监测。 上述前三个目标将通过以下方式实现 几种类型的电生理输入/输出分析，主要 在系统层面上。信息论的原理将被应用于 获得的数据是定量的、独立于模型的量度 在感觉感受器的尖峰序列中编码的信息 初级感觉中间神经元。第四个目标将通过 进一步的电生理测量，结果将是 体现在基于生理学的系统模型中。模型将是 在信息论的基础上提炼，并检验其有效性 类似于在真实系统上进行的分析。 第五个目标将通过计算约束条件来实现 气流中热噪声对系统性能的影响 环境。第六个目标将通过计算机实现 机械感受器和中间神经元特性的模拟。 这些研究将阐明与最佳信号相关的一般原理 在感觉系统内的处理，并可能建议通用算法 通过神经元集合对信息进行高效编码。