CIRCUIT MECHANISMS SHAPING OLFACTORY CORTICAL RESPONSES DURING PASSIVE AND ACTIVE

描述（由申请人提供）：感官研究的一个中心问题是理解行为相关刺激如何在神经网络的活动中表现出来。在这个提议中，我们探索了嗅觉系统中神经元回路功能和行为之间的联系。当动物遇到新的气味或环境时，它们会迅速从被动呼吸转变为主动嗅闻。在人类中，帕金森病患者的嗅觉受损会导致嗅觉任务缺陷。虽然嗅闻被认为在嗅觉感知的形成中起着重要作用，但目前还不知道皮层网络如何处理嗅闻过程中获得的信息。我们在本提案中描述的实验研究了产生动态皮层反应模式的细胞和电路水平机制，这些反应模式反映了被动呼吸与主动嗅探期间获得的输入。我们的初步数据表明，短期突触可塑性嗅球输入和本地interneuron微电路协同作用，产生差异的皮质人口的反应，在被动呼吸与主动嗅探。我们将使用体外钙成像和同步多神经元电生理记录的组合来阐明突触可塑性和回路结构在塑造皮层反应中的作用。这样一个机制和详细的分析嗅觉皮层回路将提供一个重要的框架，了解嗅觉信息是如何处理在被动和主动行为状态。

DESCRIPTION (provided by applicant): A central issue in sensory research is understanding how behaviorally relevant stimuli are represented in the activity of neural networks. In this proposal, we explore the links between the function of neuronal circuits and behavior in the olfactory system. When animals encounter a novel odorant or environment they quickly transition from passive respiration to active sniffing. In humans, impaired sniffing in Parkinson's patients leads to olfactory task deficits. Although sniffing is proposed to play an important role in the formation of olfactory percepts, it is not known how cortical networks process information acquired during sniffing. The experiments we describe in this proposal investigate the cellular and circuit-level mechanisms that produce dynamic cortical response patterns that are reflective of input obtained during passive respiration versus active sniffing. Our preliminary data suggests that short-term synaptic plasticity in olfactory bulb inputs and local interneuron microcircuits act synergistically to produce differential cortical population responses during passive respiration versus active sniffing. We will use a combination of in vitro calcium imaging and simultaneous, multi-neuron, electrophysiological recording to elucidate the roles of synaptic plasticity and circuit architecture in shaping cortical responses. Such a mechanistic and detailed analysis olfactory cortical circuitry will provide an important framework for understanding how olfactory information is processed during passive and active behavioral states.