Oscillation and Temporal Encoding of Olfactory Info

嗅觉信息的振荡和时间编码

• 批准号: 7054661
• 负责人: GILLES J LAURENT
• 金额: $ 33.47万
• 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 2008-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7054661
• 关键词: Orthoptera; electrodes; electrophysiology; memory; nerve threshold; neural information processing; neuroanatomy; neurophysiology; odors; olfactions; olfactory lobe; olfactory stimulus

DESCRIPTION (provided by applicant): Electroencepholographic recordings from the human brain reveal complicated waveforms - often oscillatory - with energy in many different frequency bands. This activity (e.g., the energy of 40 Hz signals) is usually state-dependent and varies with the subject's attentiveness or wakefulness. Some of the most dramatic modulations occur in the different phases of sleep. These macroscopic signals generally represent the synchronized activity of large numbers of neurons that fire periodically and occur in all mammals, non-mammalian vertebrates and smaller animals such as insects and molluscs. The functional relevance of these signals -thus, of the signals that cause them-remains, however, largely conjectural. The present work is directed at deciphering some of these neural, distributed and coordinated phenomena and at providing a functional and computational understanding of their existence. The approach exploits the accessibility of small nervous systems (insect brains) and the prevalence of such coordinated phenomena in olfactory circuits (insect olfactory system: antennal lobe and mushroom bodies). The methods used are electrophysiological (intracellular and multi-single unit recordings) and computational (quantitative analysis, simulations). Because olfactory circuits in insects and mammals are so alike, the potential payoff of this work is a better understanding of neural coding, olfactory representations and of the format of memories in brain circuits in general. For example, the fundamental problem of representation sparsity (i.e., whether a memory should be represented by a large or small subset of a neural assembly) can be studied directly in ways that are impossible today with the large brains of mammals. This work will thus have relevance to present efforts to decipher memory circuits in rodents and primates and coding strategies used by the human brain.

描述（由申请人提供）：人脑的脑电图记录揭示了复杂的波形 - 通常是振荡的 - 能量处于许多不同的频段。这种活动（例如 40 Hz 信号的能量）通常与状态相关，并且随着受试者的注意力或觉醒程度而变化。一些最显着的调节发生在睡眠的不同阶段。这些宏观信号通常代表大量神经元的同步活动，这些神经元周期性地放电并发生在所有哺乳动物、非哺乳动物脊椎动物和较小的动物（例如昆虫和软体动物）中。然而，这些信号的功能相关性——以及导致它们的信号的功能相关性——在很大程度上仍然是推测性的。目前的工作旨在破译其中一些神经、分布式和协调现象，并提供对其存在的功能和计算理解。该方法利用了小神经系统（昆虫大脑）的可访问性以及嗅觉回路（昆虫嗅觉系统：触角叶和蘑菇体）中这种协调现象的普遍性。使用的方法是电生理学（细胞内和多单元记录）和计算（定量分析、模拟）。由于昆虫和哺乳动物的嗅觉回路非常相似，这项工作的潜在回报是更好地理解神经编码、嗅觉表征和大脑回路中的记忆格式。例如，表征稀疏性的基本问题（即，记忆是否应该由神经集合的大子集还是小子集来表示）可以直接以目前哺乳动物大脑无法实现的方式进行研究。因此，这项工作将与目前破译啮齿动物和灵长类动物的记忆回路以及人脑使用的编码策略的努力相关。