Circuit reconstruction of functionally-identified neurons in deep brain regions: application to grid cells

项目摘要 自20世纪60年代以来，专门的突触接线基序一直被怀疑是认知的基本组成部分。 现代神经科学的诞生然而，测试这些想法的技术在历史上一直不可用。 内侧内嗅皮层（MEC）的网格细胞系统是这个问题的一个范例。网格 细胞对记忆和导航至关重要。它们被认为是阿尔茨海默氏症发展的关键 疾病然而，由于技术上的原因，网格细胞活动的基本机制还不清楚。 评估网格单元布线模式的障碍。在这里，我建议通过开发一个 用于脑深部区域中功能特征化神经元的电路重建的流水线。我的论文 到目前为止，我们的工作（目标1）包括共同开发这样一条用于大脑表层区域的管道，然后是适应性 该程序用于脑深部区域，使用植入式光学器件、多光子钙成像 在行为，电子显微镜，和多模式技术，以登记功能和解剖 数据在独立阶段（F99，目标2），我将把这个管道应用到MEC中的网格单元， 对当前网格细胞功能理论所预测的布线模式的明确反驳或确认。我 然后提供一个博士后计划（K00，目标3），用于创建下一代多光子成像， 啮齿动物行为技术这个博士后培训在光学设计和工程的接口 方法的目的是扩大目前的能力，监测神经活动，重建神经回路， 测试大脑功能的理论总的来说，这个建议将使我能够发展电路重建的技能 和神经科学的方法开发，提高作为独立职业的可能性 学术界的调查员。最后，我预计拟议的研究将提高技术能力， 神经科学，并提供基本的洞察电路架构的基础记忆和认知 大脑回路与迫切的健康需求高度相关。

Project Abstract Specialized synaptic wiring motifs have been suspected to be essential building blocks of cognition since the birth of modern neuroscience. However the technology to test these ideas has been historically unavailable. The grid cell system in medial entorhinal cortex (MEC), a deep brain area, is an exemplar of this problem. Grid cells are essential for memory and navigation. They are thought to be key in the development of Alzheimer’s disease. Yet the fundamental mechanisms underlying grid cell activity are not understood, owing to technical barriers in assessing grid cells’ wiring patterns. Here I propose to overcome these barriers, by developing a pipeline for circuit reconstruction of functionally-characterized neurons in deep brain areas. My dissertation work thus far (Aim 1) has involved co-development of such a pipeline for surface brain areas, then adaptation of this procedure for deep brain areas, using a combination of implantable optics, multiphoton calcium imaging during behavior, electron microscopy, and multimodal techniques to register both functional and anatomical data. During the independent phase (F99, Aim 2), I will apply this pipeline to grid cells in MEC, enabling definitive refutation or confirmation of the wiring patterns predicted by current theories of grid cell function. I then provide a postdoctoral plan (K00, Aim 3) for the creation of next-generation multiphoton imaging and rodent behavioral technology. This postdoctoral training at the interface of optical design and engineering methods aims to expand current capabilities for monitoring neural activity, reconstructing neural circuits, and testing theories of brain function. Overall this proposal will enable me to develop skills in circuit reconstruction and methods development for neuroscience, enhancing the probability of a career as an independent investigator in academia. Finally, I anticipate that the proposed studies will advance technical capabilities for neuroscience, and provide fundamental insight into the circuit architectures underlying memory and cognition in a brain circuit highly relevant to pressing health needs.