Dynamics of odor coding and processing by neural circuits in the olfactory bulb

嗅球神经回路的气味编码和处理动力学

基本信息

批准号：
10664878
负责人：
DALE M WACHOWIAK
金额：
$ 32.41万
依托单位：
UNIVERSITY OF UTAH
依托单位国家：
美国
项目类别：
财政年份：
2021
资助国家：
美国
起止时间：
2021-08-01 至 2026-07-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10664878
关键词：
Afferent Neurons Animal Behavior Animals Automobile Driving Behavior Brain Calcium Cells Chemistry Code Color Complex Dependence Detection Environment Esthesia Frequencies Generations Glutamates Goals Head Image Inhalation Link Modeling Monitor Mus Nature Nervous System Neurons Neurosciences Odors Olfactory Pathways Optical reporter Organ Output Pathway interactions Pattern Play Process Property Role Sampling Sensory Sensory Process Shapes Signal Transduction Smell Perception Stimulus Synapses Testing Therapeutic Time Work awake behavioral response design experimental study improved in vivo information processing innovation insight neural neural circuit olfactory bulb olfactory stimulus optogenetics pharmacologic postsynaptic predictive modeling presynaptic response sensor sensory input sensory prosthesis sensory system temporal measurement

项目摘要

PROJECT SUMMARY A fundamental step in understanding sensation is understanding how neural circuits in the brain transform patterns of sensory neuron activity into robust and efficient representations of the external world. Sensation is an active process in which the detection and initial encoding of sensory information is dynamically modulated by sampling behavior. Understanding how central circuits process sensory information in the context of active sampling is critical for understanding the neural basis of sensation in the behaving animal. The goals of this project are to understand how neural circuits in the mammalian olfactory bulb transform sensory inputs in vivo and in the context of active odor sampling, or sniffing. First, we will examine circuit-level determinants of the diverse patterns of excitatory drive onto mitral and tufted cells, focusing on the respective roles of sensory inputs and glomerular circuits in generating this diversity. Second, we will define if and how stimulus features themselves – in particular, odorant chemistry and intensity – relate to the dynamics of excitatory drive onto MT cells, as well as how these dynamics are shaped by sniffing behavior. Finally, we will ask how dynamics and glomerular patterns of excitatory input impact the input-output transformation of the olfactory bulb. The proposed experiments implement several innovative approaches to dissecting circuit function in the intact olfactory bulb; these include using second-generation optical reporters of glutamate to directly image excitatory signaling onto mitral/tufted cells with high temporal resolution, dual-color imaging of glutamate and calcium to simultaneously monitor presynaptic inputs and readouts of mitral/tufted cell activity from the same glomerulus, and the use of identified glomeruli with well-characterized response spectra to design powerful tests of model predictions. The overall impact of the project will be to advance a mechanistic understanding of the relationship between the dynamics of odor sampling and the resulting dynamics of neural activity in the olfactory bulb. These findings will pave the way for ultimately understanding the role that neural dynamics and active sampling play in odor perception.

项目概要理解感觉的一个基本步骤是理解大脑中的神经回路将感觉神经元活动模式转化为外部世界的稳健且有效的表征。感觉是一个主动的过程，其中感觉信息的检测和初始编码是动态的通过采样行为进行调节。了解中央电路如何处理感官信息。主动采样的背景对于理解行为动物感觉的神经基础至关重要。该项目的目标是了解哺乳动物嗅球中的神经回路如何转变体内和主动气味采样或嗅觉背景下的感觉输入。首先，我们将检查二尖瓣兴奋性驱动的不同模式的电路级决定因素和簇状细胞，重点关注感觉输入和肾小球回路在产生这种信号中各自的作用其次，我们将定义刺激本身是否以及如何表现——特别是气味化学和刺激。强度 – 与 MT 细胞兴奋性驱动的动力学以及这些动力学如何形成有关最后，我们将询问兴奋性输入的动态和肾小球模式如何影响嗅球的输入输出转换。所提出的实验实施了几种创新方法来剖析电路功能完整的嗅球；其中包括使用第二代谷氨酸光学产生器直接成像二尖瓣/簇状细胞上的兴奋性信号传导具有高时间分辨率、谷氨酸和双色成像钙同时监测突触前输入和二尖瓣/簇状细胞活动的读数肾小球，以及使用具有良好表征的响应谱的已识别肾小球来设计强大的模型预测的检验。该项目的总体影响将是促进对这种关系的机械理解气味采样的动态与嗅球神经活动的动态之间的关系。这些发现将为最终理解神经动力学和主动性的作用铺平道路气味感知中的采样游戏。