Deciphering the neural circuits that mediate innate olfactory behaviors.

项目摘要 大脑将外部世界的内部表征转化为适当的行为。澄清： 感官信息如何通过分级系统传播是迈向 了解大脑如何指导行为。嗅觉是一个易于处理的模型，因为 从鼻子到杏仁核的联合皮质和情绪结构相对简洁。先天的 动物之间的行为是刻板印象的，很可能是遗传决定和保守的结果 电路，使它们成为一个容易驾驭的模型。我们过去的工作揭示了杏仁皮质(PlCoA)的环路。 调节天生的吸引力和对气味的厌恶。了解感觉器官是如何连接到大脑的 不同价态的产生行为是一个重要的生物学问题，可以为 对感官刺激的情绪反应。我们将解剖追踪和功能追踪相结合 操作以揭示plCoA的两个输出，伏隔核(NAC)和杏仁内侧核(MeA)， 分别能够引起接近和回避反应。此外，我们有证据证明 建议plCoA电路有一个地形组织。因此，我们假设plCoA 包含按地形组织的标记线，以赋予气味诱发行为的价态。 该提案的目标是破译plCoA电路及其到NAC和MEA的连接。我们 已经证明杏仁皮质向NAC和MeA的投射能够产生接近和 回避行为。此外，这些投射神经元似乎彼此不同。我们提出了一个 PLCoA向NAC发送投射信号以表示正价，并向杏仁内侧核发送投射信号的模型 信号厌恶。我们将结合行为实验、病毒追踪、遗传学和 神经活动的内窥镜成像回答三个基本问题：1)plCoA投射到 Nac和mea介导气味诱发行为？2)plCoA投射神经元的解剖学特征 有组织吗？3)这些投射神经元和它们的下游目标是否表现出对价态的气味调节？这个 对这些问题的回答将填补关于气味在先天途径中的表示的知识空谈 将这一途径更深入大脑，实现行为输出。

Project Summary The brain translates internal representations of the external world into appropriate behaviors. Elucidation of how sensory information is propagated through hierarchical systems is an important step towards understanding how the brain instructs behavior. The sense of smell is a tractable model because the pathways from the nose to associational cortex and emotional structures in the amygdala are relatively concise. Innate behaviors are stereotypical between animals and likely result from genetically determined and conserved circuits, making them a tractable model. Our past work has revealed circuits in the cortical amygdala (plCoA) that mediate innate attraction and aversion to odor. Understanding how the sense organ is wired to the brain to produce behaviors of different valence is an important biological problem and may provide insight into emotional responses to sensory stimulation. We have combined anatomical tracing with functional manipulations to reveal two outputs of the plCoA, the nucleus accumbens (NAc) and medial amygdala (MeA), that are capable of eliciting approach and avoidance responses, respectively. Further, we have evidence to suggest that there is a topographic organization to the plCoA circuitry. Thus, we hypothesize that the plCoA contains topographically organized labeled lines to impart valence on odor-evoked behaviors. The goal of this proposal is decipher the plCoA circuitry and its connections to the NAc and MeA. We have demonstrated that the cortical amygdala projections to NAc and MeA are able to generate approach and avoidance behaviors. Moreover, these projection neurons appear to be distinct from each other. We propose a model whereby the plCoA sends projections to the NAc to signal positive valence, and to medial amygdala to signal aversion. We will employ a combination of behavioral experiments, viral tracing, genetics and endoscopic imaging of neuronal activity to answer three fundamental questions: 1) Do the plCoA projections to NAc and MeA mediate odor-evoked behaviors? 2) How are the plCoA projection neurons anatomically organized? 3) Do these projection neurons and their downstream targets exhibit odor tuning for valence? The answers to these questions will fill a knowledge gab about the representation of odor in the innate pathway and extend this pathway deeper into the brain towards behavioral output.