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，使复杂认知任务中神经活动的第一次细胞分辨率成像成为可能。使用遗传编码的钙传感器的细胞分辨率功能成像能够记录视野内整个神经元群体的神经活动。每个具有功能特征的神经元都可以在空间中精确定位，并在数周内进行记录。在复杂的认知任务中实现如此高分辨率的成像将提供涉及更高认知的神经回路动力学的前所未有的全面和详细的视角。老鼠是最简单的脊椎动物物种，已经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实施目标导向的感觉运动规则的能力。为了表征执行功能和其他高级认知能力背后的神经回路，我们将开发一个清醒行为大鼠的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。在目标1中，我们描述了一种新的大脑稳定方法，灵感来自于用于精确对准光学组件的运动学支架。这种新设备将被部署，这样经过训练的大鼠将在每次实验中自愿并重复激活大脑稳定设备数百次。该设备将被集成到一个半自动训练设施中，用于训练老鼠完成复杂的任务，如快速规则切换。在目标2中，我们将使用定制的自动双光子显微镜来增强培训系统。我们将开发植入式光学装置，使大脑运动最小化，同时允许通向大脑皮层表面的清晰光学路径。与训练系统一起，这些设备将被用来记录大鼠执行认知任务时大鼠额叶皮质神经元中的钙依赖荧光瞬变。

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.