NCS-FO: Nanomagnetic Stimulation Capability for Neural Investigation and Control

ECCS- Prop. No. 1533598 PI：Gong，Yiyang Institute：杜克大学标题：NCS-FO：Real-time optical readout and control of population neural activity with cellular resolution目的：本项目将开发一种机制，用于在通过光遗传学技术激活时同时控制和阅读神经活动;这种能力将超越神经研究中以前的限制。 该提案分为三个目标：1）开发在不同波长范围内活跃的钙传感器和光遗传学通道，以允许同时读出和控制，2）开发双光束双光子显微镜，3）开发可以实时处理神经活动的成像软件。理解神经功能需要检查大脑中大量神经元的特定子集。最近开发的光遗传学工具，如光遗传学刺激和钙成像，已经部分满足了靶向这些特定神经元并研究其功能的需求。这些技术将工程基因传递到目标神经群体，并使用光来操纵或测量神经活动。目前的光遗传学工具缺乏时空分辨率，无法在快速时间尺度上并行研究许多单个神经元;它们只能在近毫米大小的大脑区域或许多动作电位的时间尺度上得出广泛的结论。我们建议整合光学和遗传工具的设计和实施，以大大改善调查神经活动的规模。具体来说，我们将创建两个光学独立的通道：一个通道用于快速，空间精确的光学图案来控制单个神经元;另一个通道用于独立记录单个神经元的神经活动。然后，我们将通过创建软件来集成这两个通道，该软件基于光学记录来即时模式化光学激发。对这套广泛的工具进行集成设计和工程设计，将使神经科学家能够快速操纵和控制大量的单个神经元，这是目前还不存在的能力。我们的技术将允许社区直接探索一个大脑区域中许多单个神经元的神经活动模式如何驱动下游神经活动。这种对功能连接的新探索正是更好地理解健康和患病大脑中神经活动协调所需的研究类型。除了神经科学的具体应用外，在我们的多学科环境中培养学生将培养出能够应对当今社会面临的广泛技术挑战的下一代科学家。在过去的十年里，大脑活动的光学成像已经稳步发展成为神经科学实验室的主要技术。与神经活动的遗传编码传感器相结合，光学方法使遗传靶向和慢性，同时成像的许多个别神经元。与电生理学相比，现有光学技术的一个显著弱点是不能同时测量和控制真实的神经元的活动。我们建议通过开发一种光学成像系统和数据处理软件套件来解决这一缺点，该系统和软件套件将通过光学激发实现神经活动的实时光学读出和实时神经反馈，所有这些都具有细胞水平的特异性，并在大量神经元上并行进行。这种光学记录和操纵许多遗传或功能特定的神经元的新能力将增强当前使用批量神经激活或抑制的研究;神经元的精细尺度扰动将梳理神经回路的细节。具体来说，我们将设计一套光遗传学致动器，荧光传感器和显微镜工具，这些工具将使光学读出和控制不同波长通道的神经元成为可能。我们还将开发快速图像处理算法，快速将图像转换为单个神经元的神经活动，从而实现基于光学读数的神经活动的实时控制。最近，对这些工具的改进是独立进行的。我们的建议将解决工具集的综合开发，并有效地利用各个组成部分之间的权衡。例如，蛋白质传感器、成像处理软件和光学成像硬件的同时工程化将优化读出保真度。同样，共同设计的遗传工具？光谱分离和光学时空分辨率将提高光学控制精度。整合这些发展来检查细胞水平的神经功能是前所未有的：这项研究的成功进展将使大脑的新检查成为可能，并有助于指导有针对性的生物医学治疗。

ECCS- Prop. No. 1533598PI: Gong, Yiyang Institute: Duke UniversityTitle: NCS-FO: Real-time optical readout and control of population neural activity with cellular resolutionObjective: This project will develop a mechanism for simultaneously controlling and reading out neural activity when being activated by optogenetic techniques; this capability will surpass a previous limitation in neural studies. The proposal is separated into three aims: 1) develop calcium sensors and optogenetic channels active on different wavelength ranges to allow simultaneous readout and control, 2) develop a dual-beam two photon microscope, and 3) develop imaging software that can process neural activity in real-time. Nontechnical abstractUnderstanding neural function requires examining specific subsets of the vast numbers of neurons in the brain. Recently developed optogenetics tools, such as optogenetic stimulation and calcium imaging, have partially fulfilled the need to target these specific sets of neurons and study their function. These techniques deliver engineered genes to targeted neural populations, and use light to manipulate or measure neural activity. Current optogenetic tools lack the spatiotemporal resolution to causally study many individual neurons in parallel on fast time scales; they only make broad conclusions either on near-millimeter sized brain regions, or over the timescale of many action potentials. We propose to integrate the design and implementation of optical and genetic tools to greatly refine the scale of investigating neural activity. Specifically, we will create two optically independent channels: one channel for fast, spatially precise optical patterning to control individual neurons; and one channel for independent recording of neural activity from individual neurons. We will then integrate these two channels by creating software that instantaneously patterns optical excitation based on the optical recording. Integrative design and engineering of this expansive set of tools will enable neuroscientists to quickly manipulate and control large populations of single neurons, a capability that does not exist presently. Our technology will allow the community to directly explore how neural activity patterns of many individual neurons in one brain region drive downstream neural activity. This novel probing of functional connectivity is exactly the type of study needed to better understand the coordination of neural activity in healthy and diseased brains. Beyond the specific application of neuroscience, training students within our multidisciplinary setting will create the next generation of scientists capable of tackling the broad set of technical challenges facing society today. Technical AbstractOptical imaging of brain activity has steadily developed into a staple technique within neuroscience labs over the past decade. In combination with genetically encoded sensors of neural activity, optical methods enable genetic targeting and chronic, simultaneous imaging of many individual neurons. One significant weakness of existing optical techniques when compared to electrophysiology is the inability to simultaneously measure and control the activity of a neuron in real time. We propose to address this shortcoming by developing an optical imaging system and data processing software suite that will enable real-time optical readout of neural activity and real-time neural feedback via optical excitation, all with cellular level specificity and in parallel over a large population of neurons. This new ability to optically record and manipulate many genetically or functionally specified neurons individually will augment current studies using bulk neural activation or inhibition; the fine scale perturbations of neurons will tease apart the details of neural circuits. Specifically, we will engineer a set of optogenetic actuators, fluorescent sensors, and microscopy tools that will enable optical readout and control of neurons in different wavelength channels. We will also develop fast image processing algorithms that quickly convert images to neural activity of individual neurons, thereby enabling real-time control of neural activity based on the optical readout. Recently, improvements to these tools occurred independently. Our proposal will address the integrated development of the tool set, and effectively employ trade-offs between the individual components. For example, simultaneous engineering of the protein sensor, imaging processing software, and optical imaging hardware will optimize the readout fidelity. Similarly, joint design of the genetic tools? spectral separation and the optical spatiotemporal resolution will extend optical control precision. Integration of these developments to examine neural function at the cellular level is unprecedented: successful advancement of this research will enable novel examination of the brain and help guide targeted biomedical therapies.