Processing of temporally dynamic olfactory inputs

时间动态嗅觉输入的处理

• 批准号: 7913882
• 负责人: Ryan M Carey
• 金额: $ 2.85万
• 依托单位: BOSTON UNIVERSITY (CHARLES RIVER CAMPUS)
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-01-01 至 2011-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7913882
• 关键词: Animals; Auditory; Behavior; Binding; Cells; Code; Complex; Computer Simulation; Diagnosis; Exhibits; Goals; Human; Lead; Maps; Nervous System Physiology; Nervous system structure; Neurons; Odors; Olfactory Receptor Neurons; Organ; Output; Pattern; Process; Relative (related person); Research; Role; Sampling; Sensory; Sensory Process; Shapes; Source Code; Staging; System; Techniques; Testing; Time; Touch sensation; Translating; Visual; Visual impairment; Work; awake; imaging modality; improved; information processing; insight; nervous system disorder; olfactory bulb; optical imaging; postsynaptic; public health relevance; receptor; research study; respiratory; response

DESCRIPTION (provided by applicant): The goal of this research is to understand how odor information is encoded by the nervous system. Initially, odorants bind to olfactory receptor neurons, which project to glomeruli in the olfactory bulb, the first stage of olfactory information processing. Here, patterns of activity across thousands of receptor neurons are transformed into spatially organized maps of glomerular activation. These maps of receptor input to glomeruli are temporally dynamic, and much of their temporal dynamics are organized around the respiratory cycle. The research in this project will ask how the dynamics of receptor neuron to a glomerulus are translated into firing patterns in the output neurons that project from the olfactory bulb to the cortex (mitral/tufted cells). The projection neurons themselves exhibit complex firing patterns also organized around the respiratory cycle - in fact, it has been hypothesized that the relative timing of firing among them is important for olfactory coding - but the source of these complex dynamics has not yet been identified. This project will test the idea that the temporal dynamics of sensory input evoked during natural odor sampling (i.e., sniffing) is a strong determinant of mitral/tufted cell response patterns. The project will investigate, for the first time, how odor sampling behavior shapes both early olfactory coding at the level of the olfactory bulb and the transformation of receptor inputs into patterns of postsynaptic activity. The experiments proposed here will use optical imaging methods to directly visualize odor-evoked glomerular maps, as well as electrophysiological techniques to record activity from mitral/tufted cells, focusing on responses evoked by naturalistic sampling of odorants. In addition, a simple biophysical computational model of a mitral cell will be implemented and tested to determine its response to naturalistic glomerular input. In addition to testing, for the first time, several longstanding hypotheses about the role of sampling behavior in shaping odor codes, this work will be important in understanding how olfactory information is encoded and processed in the awake, behaving animal. PUBLIC HEALTH RELEVANCE: Understanding the basic principles of olfactory system function can lead to an increased understanding of how the nervous system processes sensory information, including visual, auditory, or touch-related input; such insights could be important in developing artificial sensory organs for humans (for the visually-impaired, for example). Understanding more about mammalian nervous system function also has the potential to lead to improved diagnosis and treatment of diseases of the nervous system.

描述（由申请人提供）：本研究的目的是了解气味信息是如何被神经系统编码的。最初，气味与嗅觉受体神经元结合，这些神经元投射到嗅球的肾小球，这是嗅觉信息处理的第一阶段。在这里，数千个受体神经元的活动模式被转化为肾小球激活的空间组织图。这些受体输入肾小球的地图是时间动态的，它们的时间动态大部分是围绕呼吸周期组织的。这个项目的研究将会问，从受体神经元到肾小球的动态是如何转化为从嗅球到皮层（二尖瓣/簇状细胞）的输出神经元的放电模式的。投射神经元本身也表现出复杂的放电模式，这些模式也围绕着呼吸周期组织起来——事实上，有人假设它们之间放电的相对时间对嗅觉编码很重要——但这些复杂动态的来源尚未被确定。该项目将测试在自然气味取样（即嗅探）过程中引起的感觉输入的时间动态是二尖瓣/簇状细胞反应模式的强烈决定因素。该项目将首次调查气味取样行为如何在嗅球水平上塑造早期嗅觉编码，以及受体输入转化为突触后活动模式。这里提出的实验将使用光学成像方法直接可视化气味诱发的肾小球图，以及电生理技术来记录二尖瓣/簇状细胞的活动，重点关注由自然气味取样引起的反应。此外，二尖瓣细胞的一个简单的生物物理计算模型将被实施和测试，以确定其对自然肾小球输入的反应。除了首次测试关于采样行为在形成气味编码中的作用的几个长期存在的假设外，这项工作对于理解嗅觉信息在清醒的行为动物中是如何编码和处理的也很重要。