Cellular Resolution Imaging Of Cortical Dynamics During Executive Function

描述（由申请人提供）：我们建议将活体成像技术与自动大鼠行为训练系统相结合。这将创造一个变革性的技术平台，使复杂认知任务期间神经活动的细胞分辨率成像成为可能。细胞分辨率功能成像使用基因编码钙传感器可以记录整个视野内的神经细胞群的神经活动。每个功能特征神经元都可以在空间中精确定位，并在数周内记录下来。在复杂的认知任务中实现如此高分辨率的成像将为涉及高级认知的神经回路动力学提供前所未有的全面和详细的视图。老鼠是最简单的脊椎动物物种，它们被训练来执行需要执行功能的行为，例如一项任务需要快速选择和执行目标导向的感觉运动规则的能力。为了描述执行功能和其他高级认知能力背后的神经回路，我们将在清醒行为的大鼠身上开发一种细胞分辨率成像系统。这将需要在成像过程中稳定大脑运动的方法。在Aim 1中，我们描述了一种新的大脑稳定方法，灵感来自用于精确对准光学元件的运动支架。这种新装置将被部署，这样经过训练的老鼠就会自愿地反复激活大脑稳定装置，在每次试验中进行数百次试验。该设备将被整合到一个半自动化的训练设施中，用于训练老鼠完成复杂的任务，比如快速切换规则。在Aim 2中，我们将用定制的自动双光子显微镜来增强训练系统。我们将开发植入式光学系统，使大脑运动最小化，同时允许清晰的光学通道到达皮质表面。与训练系统一起，这些设备将被用来记录当大鼠执行认知任务时，来自大鼠额叶皮层的神经元中钙依赖的荧光瞬变。

DESCRIPTION (provided by applicant): We propose to combine technologies for in vivo imaging with automated rat behavioral training systems. This will create a transformative technology platform that will enable the first cellular resolution imaging of neural activity durin complex cognitive tasks. Cellular-resolution functional imaging using genetically encoded calcium sensors enables recording the neural activity of the entire neuronal population within a field of view. Each functionally characterized neuron can be precisely pinpointed in space and recorded over multiple weeks. Achieving such high-resolution imaging during complex cognitive tasks will provide an unprecedentedly comprehensive and detailed view of neural circuit dynamics involved in higher cognition. Rats are the simplest vertebrate species that have been trained to perform behaviors that demand executive function, exemplified by a task requiring the ability to rapidly select and implement goal-directed sensorimotor rules. To characterize the neural circuitry underlying executive function and other higher cognitive abilities, we will develo a system for cellular resolution imaging in awake behaving rats. This will require methods to stabilize brain movements during imaging. In Aim 1 we describe a new method for brain stabilization, inspired by kinematic mounts used to precisely align optical components. The new device will be deployed so that trained rats will voluntarily and repeatedly activate the brain stabilization device over hundreds of trials within each session. The device will be integrated into a semi-automated training facility, which will be used to train rats on complex tasks such as rapid rule-switching. In Aim 2 we will augment the training system with a custom automated two-photon microscope. We will develop implantable optics that minimize brain motion while allowing a clear optical path to the cortical surface. Together with the training system, these devices will be used to record calcium dependent fluorescence transients in neurons from the rat frontal cortex while rats perform cognitive tasks.