Synaptic Processing in the Olfactory System

项目总结/摘要 在人类中，嗅觉对我们的生活质量有很大的贡献。臭是 强烈的线索唤起对过去事件的记忆，嗅觉在我们的记忆中起着重要的作用。 风味的感知。然而，在处理和编码的基础上， 大脑中的嗅觉信息并不清晰。为了解决这个问题，我们研究了 在啮齿动物嗅球中，兴奋性和抑制性神经元形成的神经元回路， 嗅觉信息最初在大脑中编码。我们还研究了 初级嗅觉（梨状）皮层中的回路，嗅觉信息的下一个主要层次 被处理了。我们的长期目标是了解神经回路最终是如何产生 感官知觉 这些实验采用光学和电生理技术， 确定两个嗅球中已识别神经元群体的响应特性 和皮质。具体目标1提出了使用慢性体内双光子记录活性 从清醒的，头部固定的嗅球中识别出的主细胞和抑制性中间神经元， 小鼠我们将使用这种方法来确定联想学习如何改变气味 行为小鼠的表征。我们假设局部中间神经元在 与学习相关的嗅球活动变化。具体目标2建议调查如何 GABA能抑制性中间神经元的特定亚型调节梨状皮质中的气味编码。 我们结合联合收割机光遗传学、脑切片和活体电生理记录来揭示 不同的中间神经元类控制皮层主体的气味诱发活动的操作 总之，这些实验将显示嗅球中的局部抑制性中间神经元是如何 和皮层调节大脑中的感觉信息处理。

Project Summary/Abstract In humans, the sense of smell contributes significantly to our quality of life. Odors are strong cues for evoking memories of past events and olfaction plays an important role in our perception of flavor. However, the mechanisms underlying the processing and encoding of olfactory information in the brain are not clear. To address this question, we study the properties of neuronal circuits formed by excitatory and inhibitory neurons in the rodent olfactory bulb, a site where olfactory information is initially encoded in the brain. We also examine the properties of circuits in the primary olfactory (piriform) cortex, the next major level at which olfactory information is processed. Our long term goal is to understand how neural circuits ultimately give rise to sensory perception The experiments proposed employ optical and electrophysiological techniques to determine the response properties of identified neuronal populations in both the olfactory bulbs and cortex. Specific Aim 1 proposes the use of chronic, in vivo two-photon recording of activity from identified principal cells and inhibitory interneurons in the olfactory bulb of awake, head-fixed mice. We will use this approach to determine how associative learning modifies odor representations in behaving mice. We hypothesize that local interneurons play an important role in learning-related changes in olfactory bulb activity. Specific Aim 2 proposes to investigate how particular subtypes of GABAergic inhibitory interneurons modulate odor coding in piriform cortex. We combine optogenetics, brain slice and in vivo electrophysiological recordings to reveal the operations by which distinct interneuron classes govern odor-evoked activity of cortical principal cells.Together, these experiments will show how local inhibitory interneurons in the olfactory bulb and cortex regulate sensory information processing in the brain.