OSCILLATIONS AND TEMPORAL ENCODING OF OLFACTORY INFO

嗅觉信息的振荡和时间编码

• 批准号: 2592097
• 负责人: GILLES J LAURENT
• 金额: $ 23.34万
• 依托单位: CALIFORNIA INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-05-01 至 2003-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2592097
• 关键词: Orthoptera; alternatives to animals in research; brain mapping; learning; neural information processing; neuroanatomy; neurons; neurophysiology; olfactions

DESCRIPTION: (Adapted from applicant's abstract): A major goal of modern neuroscience is to understand the various facets of neural coding. While it is widely accepted that firing rates of neurons usually encode features of a stimulus or of the behavioral state of the animal, recent results from mammals, insects, and mollusks suggest that temporal features of activity in single groups of neurons might also contain useful information. The goal of this proposal is therefore to explore the nature of a specific temporal coding scheme by olfactory neuronal ensembles in the brain, to assess its potential relevance for perception, and to understand some of the mechanisms that might allow decoding of temporal "messages" by downstream circuits. This work will be carried out using the olfactory system of insects, which is structured and operates along the same design principles as its vertebrate (including mammalian) counterpart, and in which stimulus-evoked oscillatory synchronization of neurons and complex temporal response patterns have recently been described. The insect nervous system contains a glomerular antennal lobe, analogous to the vertebrate olfactory bulb, and a mushroom body, analogous to the piriform cortex and downstream cortical structures. Recently a mechanism has been identified to desynchronize odor-activated antennal lobe neurons in vivo. This knowledge will be used to investigate the following: 1) The potential mechanisms for decoding temporal patterns of neural activity in the mushroom bodies, in particular the potential role of oscillations as a selective filter and the sensitivity of central neurons to the temporal structure of their input; 2) The dependence of temporal activity patterns of the antennal lobe's principal neurons on odor concentration and complexity; 3) The emergence of neuronal temporal patterns during odor "learning", by studying the evolution of the responses of principal neurons from a "naive" to a "familiar" state; and, 4) The local circuit dynamics and coupling within the antennal lobes, by examining the degree of correlation between response "noisiness" of simultaneously recorded neurons. An understanding of temporal coding schemes in a complex brain circuit specialized for pattern recognition (the olfactory system) will provide crucial insights into the basic principles of stimulus representation and recognition in sensory systems.

描述：（改编自申请人的摘要）：现代的一个主要目标 神经科学是了解神经编码的各个方面。 虽然 被广泛接受的是，神经元的放电率通常编码的特征， 刺激或动物的行为状态，最近的结果， 哺乳动物、昆虫和软体动物的研究表明， 单个神经元组也可能包含有用的信息。 的目标 因此，本提案旨在探讨特定时间的 编码方案的嗅觉神经元合奏在大脑中，以评估其 感知的潜在相关性，并了解一些机制 这可能允许下游电路对时间“消息”进行解码。 这项工作将利用昆虫的嗅觉系统进行， 结构和操作沿着相同的设计原则， 脊椎动物（包括哺乳动物）对应物，其中刺激诱发 神经元振荡同步与复杂时间响应 最近已经描述了模式。 昆虫的神经系统包含一个 球状触角叶，类似于脊椎动物的嗅球， 蘑菇体，类似于梨状皮质和下游皮质 结构. 最近已经确定了一种机制， 气味激活的触角叶神经元。 这些知识将用于 研究以下内容：1）解码的潜在机制 蘑菇体神经活动的时间模式，特别是 振荡作为选择性过滤器的潜在作用和灵敏度 2）中央神经元的时间结构的输入; 触角叶主动脉的时间活动模式依赖性 神经元对气味浓度和复杂性的影响; 3）神经元的出现 气味“学习”过程中的时间模式，通过研究 主神经元从“幼稚”状态到“熟悉”状态的反应;以及，4） 局部电路动力学和触角叶内的耦合， 检查响应“噪声”之间的相关程度， 同时记录神经元。 对时间编码的理解 在一个专门用于模式识别的复杂大脑回路中， 嗅觉系统）将提供重要的见解的基本原则， 感觉系统中的刺激表征和识别。