Neuronal ensembles in the rodent visual cortex

项目总结/摘要 在感官体验期间，视网膜将各种各样的视觉信息传输到大脑。神经元 沿着皮层下和皮层通路必须快速处理导航通过 世界我们的目标是了解长距离皮层连接的特异性是如何构成大脑皮层神经元的基础的。 视觉信息在多个皮层区域的分布，以及这些皮层区域如何服务于上下文- 依赖性感觉行为 视觉神经科学中的一个主要假设是，感觉信息被分成平行的流， 哪些神经元亚群将轴突发送到专门处理不同视觉信息的皮层区域 功能.对食肉动物和灵长类动物的研究已经提出了这一重要假设，但许多方面的研究表明， 它仍然未经测试，因为现有的工具不能令人满意地在细胞一级解决这个问题。 最近为小鼠开发的光学和遗传工具有望改变视觉皮层的研究 功能，它与底层电路的关系，以及它在行为中的作用。我们目前的建议将建立一个 小鼠模型，用于研究多个皮层区域的视觉微电路，并开始描述 它们之间的功能连接。 我们发现警觉小鼠初级视皮层（V1）神经元的感觉反应是： 调谐到宽范围的空间和时间频率。这表明有丰富的代表性 在视觉皮层处理的第一阶段。我们的初步数据显示， 较高的视觉区域编码时间和空间频率的减小的和互补的范围， 与基于并行处理的功能组织相一致。在这份补助金中，我们建议衡量 这种视皮层区域之间感受场特性的差异（目的1），以确定 这种平行组织的基础电路（目标2），并评估这些途径是否是 行为差异调制（目标3）。这项工作将为将具体地区的 从计算到行为--如物体识别和导航--依赖于对 独特的视觉特征。

Project Summary/Abstract During sensory experience, the retina transmits a diverse array of visual information to the brain. Neurons along subcortical and cortical pathways must rapidly process the features necessary for navigating through the world. Our goal is to understand how the specificity of long-range cortical connectivity underlies the distribution of visual information to multiple cortical areas, and how these cortical areas subserve context- dependent sensory behaviors. A major hypothesis in visual neuroscience is that sensory information is segregated into parallel streams, in which subpopulations of neurons send axons to cortical areas that are specialized to process distinct visual features. Studies in carnivores and primates have developed this important hypothesis, but many aspects of it remain untested because the tools at hand could not satisfactorily address this question at a cellular level. Recent optical and genetic tools developed for the mouse promise to transform the study of visual cortical function, its relationship to underlying circuitry, and its role in behavior. Our current proposal will establish a mouse model for studying visual microcircuitry across multiple cortical areas and begin to describe rules of functional connectivity between them. We have found that the sensory responses of neurons in the primary visual cortex (V1) of alert mice are tuned to a wide range of spatial and temporal frequencies. This suggests that there is a rich representation of visual experience at the first stage of visual cortical processing. Our preliminary data suggest that two higher visual areas encode reduced and complementary ranges of temporal and spatial frequencies, consistent with a functional organization based on parallel processing. In this grant, we propose to measure this divergence of receptive-fields properties between visual cortical areas (Aim 1), to determine the circuitry underlying this parallel organization (Aim 2), and to assess whether these pathways are differentially modulated by behavior (Aim 3). This work will provide the basis for linking area-specific computations to behaviors-- such as object recognition and navigation-- that rely on the processing of distinct visual features.