Understanding functional transformations carried out by the bulb

项目总结/摘要 嗅觉功能受损与衰老过程以及许多人类疾病有关。 我们对大脑的不完全理解使得理解大脑的基本机制变得很有挑战性。 这些感觉缺陷和其他精神疾病。了解感官信息是如何编码的， 由神经回路转化的神经网络将有助于定义这些挑战背后的基本机制。对于许多 对于动物来说，嗅觉是识别和定位食物、配偶和危险的关键。气味识别需要 识别强度可能不同的特定气味，而定位涉及检测浓度 在时间和空间上变化的轮廓。这两个过程都必须在刺激被嵌入到一个 复杂的化学背景。这需要嗅觉系统识别并保持浓度- 不变的气味表示，同时检测其变化的浓度梯度和分割其 不受环境中其他化学刺激的影响。了解大脑如何执行这些 过程是理解知觉稳定性的关键。这个提议的目的是定义神经回路 支持气味识别和调节敏感性以适应体内复杂嗅觉场景的能力。一是 将定义气味浓度的变化是如何在嗅球回路中编码和转换的。 接下来，我们将研究不同浓度或持续时间的气味暴露如何影响嗅球 对未来气味刺激的反应然后，我们将测试假设，嗅球适应的基础， 动态范围调节涉及在不同气味背景下保持灵敏度。这项建议会 用成像方法测量嗅觉感受器的神经活动来回答这些问题 神经元输入和支配嗅球小球的二尖瓣/簇状细胞输出。我们将把这个策略 用一个机械的工具包来剖析驱动功能转换的底层机制， 灯泡这一建议的影响将是产生一个全面的机械描述如何两个 感知功能是由嗅球执行的，这是关键的第一步，最终将链接 生理学与自然主义行为

Project Summary/Abstract Compromised olfactory function is associated with the aging process, as well as a number of human diseases. Our incomplete understanding of the brain makes it challenging to comprehend the mechanisms that underlie these sensory deficits and other psychiatric disorders. Understanding how sensory information is encoded and transformed by neural circuits will help define the basic mechanisms that underlie these challenges. For many animals, smell is critical for recognizing and locating food, mates and dangers. Odor recognition requires the identification of a specific smell that can vary in intensity, while localization involves detecting a concentration profile that varies in time and space. Both processes must be carried out while the stimulus is embedded in a complex chemical context. This requires that the olfactory system recognize and maintain a concentration- invariant representation of the odor, while detecting its changing concentration gradient and segmenting its percept from other chemical stimuli present in the environment. Understanding how the brain carries out these processes is key to understanding perceptual stability. The goal of this proposal is to define the neural circuits that support odor recognition and the ability to adjust sensitivity to complex olfactory scenes in vivo. First, we will define how changes in odor concentration are encoded and transformed across the olfactory bulb circuit. Next, we will examine how different concentrations or durations of odor exposure impact olfactory bulb responses to future odor stimulation. We will then test the hypothesis that olfactory bulb adaptation underlies dynamic range adjustments involved in maintaining sensitivity in different odor backgrounds. This proposal will answer these questions using an imaging approach to measure the neural activity from the olfactory receptor neuron input, and the mitral/tufted cell output that innervate olfactory bulb glomeruli. We will pair this strategy with a mechanistic toolkit to dissect the underlying mechanisms that drive functional transformations in the bulb. The impact of this proposal will be to generate a comprehensive mechanistic description of how two perceptual functions are carried out by the olfactory bulb, which are the critical first steps that will ultimately link physiology with naturalistic behavior.