An Origin of Temporal Coding in the Early Olfactory System

早期嗅觉系统中时间编码的起源

• 批准号: 9188585
• 负责人: Kristina Penikis
• 金额: $ 3.98万
• 依托单位: NEW YORK UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-10-31 至 2018-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9188585
• 关键词: Origin; Temporal; Coding; Early; Olfactory

 DESCRIPTION (provided by applicant): A fundamental goal in the field of neuroscience is to learn how the brain processes sensory information. Understanding how neurons represent sensory stimuli under normal conditions provides the ability to identify compromised components in situations of pathology and develop specific, targeted strategies to treat them. The rodent olfactory system presents many unique advantages to probe sensory coding schemes, including that it is anatomically compact and is fully amenable to all current genetic tools. The field has made great progress since the discovery that families of olfactory receptor genes define many discrete channels of information providing the input to the olfactory bulb through glomeruli1. Still, there is no cohesive theory for how neural codes in the olfactory system build representations of odor features. This proposal approaches the question by proposing a model to link the representations on the input and output levels of the olfactory bulb and testing its predictions experimentally. Specifically, the project seeks to explain the source o the temporal structure observed in responses of the population of mitral and tufted cells (MTCs), each of which receives input from a single glomerulus, and which form the output of the bulb. Our core hypothesis is that the sequence in which an odor activates glomeruli directly influences the sign and timing of responses in the connected MTCs. Aim 1 tests the basic prediction of the model: that the earlier glomeruli in the spatiotemporal sequence activated by an odor will evoke mainly early, excitatory responses in the connected MTCs, while cells receiving input from later glomeruli will show a heterogeneous set of responses. Aim 2 will determine if this coding scheme holds over a range of concentrations, as the underlying mechanism in the model predicts. Aim 3 causally probes whether earlier activation of a glomerulus within the population decreases heterogeneity of responses of its MTCs. The proposed coding scheme has the potential to convey information about the identity of an odor in a way that is tolerant to changes in concentration. These ideas will be tested using recent technological advances in optogenetics and electrophysiology that allow the researchers to target and record odor activity from MTCs that are functionally connected to a specific glomerular channel. The proposed experiments will form the basis of the Primary Investigator's graduate dissertation work and will be carried out over the next 3 years. The Sponsor will provide guidance throughout the process, and particularly with the computational aspects and analyses. The work will be presented at scientific meetings and will be published and made available to the public when completed.

 描述（由适用提供）：神经科学领域的基本目标是了解大脑如何处理感官信息。了解神经元如何在正常条件下代表感觉刺激，可以在病理学的情况下识别损害成分的能力，并制定特定的，有针对性的策略来治疗它们。啮齿动物嗅觉系统具有探测感觉编码方案的许多独特优势，包括它在解剖学上是紧凑的，并且完全适合所有当前遗传工具。自从发现嗅觉受体基因家族定义了许多信息通道以来，该领域取得了长足的进步，从而通过glomerullulli1为嗅球提供了输入。尽管如此，对于嗅觉系统中的神经代码如何构建气味特征表示的神经代码仍没有凝聚力理论。该建议通过提出一个模型来解决问题，以将表示形式链接到嗅球的输入和输出水平并通过实验测试其预测。具体而言，该项目试图解释二尖瓣和簇细胞群体（MTC）的响应中观察到的临时结构，每个结构都会从单个肾小球接收输入，并形成灯泡的输出。我们的核心假设是，气味激活Glomerulli的序列直接影响连接的MTC中响应的符号和时机。 AIM 1测试了模型的基本预测：由气味激活的空间时间序列中的较早的glomerulli将主要引起连接的MTC中的早期兴奋性响应，而后来从肾小球接收输入的细胞将显示出异质的响应集。 AIM 2将确定该编码方案是否在模型预测中的基本机制中是否存在一系列浓度。 AIM 3有可能出现问题，是否在人群中早期激活肾小球是否会下降其MTC的反应异质性。所提出的编码方案有可能以容忍集中度变化的方式传达有关气味身份的信息。这些想法将使用光遗传学和电生理学的最新技术进步进行测试，这些技术使研究人员能够靶向和记录来自功能连接到特定肾小球通道的MTC的气味活性。拟议的实验将构成主要研究者的研究生论文工作的基础，并将在未来3年内进行。赞助商将在整个过程中，尤其是在计算方面和分析中提供指导。这项工作将在科学会议上介绍，并将在完成后发布并提供公众。