Grimaud Julien, Lledo Pierre-Marie
Institut Pasteur, Laboratory for Perception and Memory, F-75015 Paris, France Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 3571, F-75015 Paris, France.
Institut Pasteur, Laboratory for Perception and Memory, F-75015 Paris, France Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 3571, F-75015 Paris, France
Learn Mem. 2016 May 18;23(6):249-54. doi: 10.1101/lm.041269.115. Print 2016 Jun.
For hundreds of years, the sense of smell has generated great interest in the world literature, oenologists, and perfume makers but less of scientists. Only recently this sensory modality has gained new attraction in neuroscience when original tools issued from physiology, anatomy, or molecular biology were available to decipher how the brain makes sense of olfactory cues. However, this move was promptly dampened by the difficulties of developing quantitative approaches to study the relationship between the physical characteristics of stimuli and the sensations they create. An upswing of olfactory investigations occurred when genetic tools could be used in combination with devices borrowed from the physics of light (a hybrid technique called optogenetics) to scrutinize the olfactory system and to provide greater physiological precision for studying olfactory-driven behaviors. This review aims to present the most recent studies that have used light to activate components of the olfactory pathway, such as olfactory receptor neurons, or neurons located further downstream, while leaving intact others brain circuits. With the use of optogenetics to unravel the mystery of olfaction, scientists have begun to disentangle how the brain makes sense of smells. In this review, we shall discuss how the brain recognizes odors, how it memorizes them, and how animals make decisions based on odorants they are capable of sensing. Although this review deals with olfaction, the role of light will be central throughout.
数百年来，嗅觉一直引发着世界文学界、酿酒师和香水制造商的浓厚兴趣，但在科学界却较少受到关注。直到最近，当生理学、解剖学或分子生物学的原始工具可用于解读大脑如何理解嗅觉线索时，这种感官模式才在神经科学领域获得了新的吸引力。然而，这一进展很快就因开发定量方法来研究刺激的物理特征与其所产生的感觉之间的关系所面临的困难而受到抑制。当基因工具与从光物理学借用的设备（一种称为光遗传学的混合技术）结合使用，以仔细研究嗅觉系统并为研究嗅觉驱动行为提供更高的生理精度时，嗅觉研究出现了上升趋势。这篇综述旨在介绍最近的一些研究，这些研究利用光来激活嗅觉通路的组成部分，如嗅觉受体神经元或位于下游的神经元，同时保持其他脑回路的完整。随着利用光遗传学解开嗅觉之谜，科学家们开始弄清楚大脑是如何理解气味的。在这篇综述中，我们将讨论大脑如何识别气味、如何记忆气味，以及动物如何根据它们能够感知的气味做出决策。尽管这篇综述涉及嗅觉，但光的作用将贯穿始终。
