TEMPORAL CODING IN OLFACTORY BULB CIRCUITS

本项目的直接目标是了解 嗅球神经元的时间尖峰模式和 气味编码 长期目标是将这些发现与 大脑其他区域的信息编码。 假设是 在这里检查的是，尖峰发生在不同的时间相对于 刺激脉冲由不同的电路部件产生 携带不同的刺激信息。 这些实验 旨在研究脊椎动物的嗅球回路如何与 输出二尖瓣和簇状细胞（MT）的尖峰模式。两 问题将被解决：1）使用受体拮抗剂作为工具，如何 NMDA和非NMDA谷氨酸受体的输入是否有差异 气味引发的MT峰值模式 假设是，非- NMDA输入对短潜伏期发放的贡献大于NMDA输入， 因此对爆发潜伏期有较大的影响; 2）GABA能输入 对早期和晚期抑制的作用不同 在MT气味反应中？ GABA和GABA受体拮抗剂将被 在细胞外记录期间应用，以检验假设， GABA能输入有助于MT尖峰潜伏期和 抑制后的尖峰。 如下文所述， 已经有许多研究使用了药理学工具， 为了剖析电刺激引起的反应，很少有人使用 这些工具在气味刺激期间，并且在脊椎动物中没有一个具有 将这些反应成分与动物的行为能力联系起来， 动物 这里提出的项目将提供这方面的新资料 气味编码过程的重要方面，并进一步我们 在感觉系统中的信息处理知识，在学习和 记忆，并在编码和分类的信息， 决策过程。 像这样的研究将是至关重要的， 了解大脑与行为的关系

The immediate goal of this project is to understand the relationship between temporal spiking patterns in neurons in the olfactory bulb and odorant coding. The long term goal is to relate these finding to information coding in other regions of the brain. The hypothesis to be examined here is that spikes occurring at different times relative to a stimulus pulse are generated by different circuit components and thus carry different information about the stimulus. These experiments are designed to examine how vertebrate olfactory bulb circuits relate to spike patterns of the output mitral and tufted cells (MTs). Two questions will be addressed: 1)Using receptor antagonists as tools, how do NMDA and non-NMDA glutamate receptor inputs contribute differentially to odorant-elicited MT spiking patterns? The hypothesis is that non- NMDA input contributes more than NMDA input to short latency spiking, and thus has a larger effect on burst latency; 2) Do GABAergic inputs contribute differentially to both early and late periods of suppression in MT odorant responses? GABA and a GABA receptor antagonist will be applied during extracellular recording to test the hypothesis that GABAergic inputs contribute to both MT spiking latency and to suppression following spiking. Although, as described below, there have been a number of studies in which pharmacological tools have been used to dissect responses elicited by electrical stimulation, few have used these tools during odor stimulation, and in the vertebrate none have related these response components to the behavioral capabilities of the animal. The projects proposed here will provide new information on this important aspect of the odorant encoding process, and further our knowledge of information processing in sensory systems, in learning and memory, and in the coding and categorization of information during decision making processes. Studies such as these will be critical in understanding brain/behavior relationships.