Decoding network activity states using sparse optical sampling

使用稀疏光学采样解码网络活动状态

• 批准号: 9456155
• 负责人: Ben W Strowbridge
• 金额: $ 28万
• 依托单位: CASE WESTERN RESERVE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-08-15 至 2019-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9456155
• 关键词: Acute; Animals; Area; Behavior; Biological Assay; Biological Models; Biological Neural Networks; Brain; Brain region; Cells; Computer Simulation; Detection; Disease model; Dyes; Electrodes; Epilepsy; Experimental Models; Goals; Hilar; Image; Imaging Techniques; Impaired cognition; Individual; Label; Lead; Light; Masks; Methodology; Methods; Microscope; Monitor; Morphologic artifacts; Motion; Neurodegenerative Disorders; Neurodevelopmental Disorder; Neurons; Neurosciences; Noise; Optical Methods; Optics; Output; Pathway interactions; Pattern; Perforant Pathway; Performance; Phase; Photometry; Photons; Population; Process; Publications; Resolution; Rodent; Sampling; Series; Signal Transduction; Site; Slice; Source; Stimulus; System; Techniques; Testing; Therapeutic; Work; base; brain tissue; calcium indicator; dentate gyrus; detector; experimental study; extracellular; in vivo; in vivo imaging; innovation; insight; light transmission; multi-electrode arrays; nervous system disorder; non-invasive imaging; optical imaging; patch clamp; prototype; public health relevance; response; simulation; two-photon

Project Summary This proposal is focused on developing new technological approaches to study how local circuits in cortical brain regions function. The central goal of this project is to develop a new recording method, we term “random aperture photometry”, that can monitor network state optically in combination with fluorescent Ca indicator probes that reflect activity in individual neurons. Unlike conventional photometry approaches where the entire microscope field-of-view is monitored using a sensitive light detector, in the method we propose to split the microscope output into multiple parallel image paths, each passing through a different mask that only allows light transmission through small apertures. By monitoring the total light transmission through the mask, this method generates an optical signal that sparsely samples the field of neurons labeled with fluorescent activity indicators. By employing multiple, independent image paths—each containing a mask with a different random arrangement of apertures—we can generate multiple signals that each reflect the ongoing network activity but are only weakly correlated. Our preliminary experiments and computer simulations suggest that signals from four independent masked pathways will likely be sufficient to decode network states evoked by different stimuli applied to the input layer of the dentate gyrus. The proposed work will use computer simulations, whole-cell patch clamp recording and optical methods to optimize and refine this method. We then will validate the ability of this new optical method to decode network states using bulk-loaded fluorescent Ca imaging while simultaneously assaying neuronal behavior using multiple intracellular recordings. We have used the intracellular recording-based method of assaying network states through a series of four recent publications. As with these previous studies, the proposed experimental work will be conducted using standard acute rodent brain slices. We believe this method is unique in providing non-invasive “whole-circuit” views of circuit function and will be especially useful in identifying specific network states and the dynamics of network state transitions. This method is also complementary with standard multi-electrode array recordings and 2-photon Ca imaging techniques. While these methods also can sample over a wide area of brain tissue, the primary goal of both techniques (and conventional extracellular unit recordings) is to estimate activity in individual neurons. By contrast, our method intentionally sacrifices spatial resolution to generate network state-specific optical signals with high signal-to-noise ratios. Since our method uses standard Ca indicator dyes and single photon excitation, it can easily be applied in vivo once the methodological details are refined and validated through the proposed brain slice experiments.

项目概要 该提案的重点是开发新技术方法来研究本地电路如何 皮质大脑区域的功能。该项目的中心目标是开发一种新的记录方法， 我们称之为“随机孔径光度测量”，它可以结合光学方式监控网络状态 反映单个神经元活动的荧光 Ca 指示剂探针。与传统的不同 使用敏感光监控整个显微镜视野的光度测定方法 探测器，在我们建议将显微镜输出分成多个并行图像路径的方法中， 每个都穿过不同的掩模，该掩模仅允许光通过小孔径传输。经过 监测通过掩模的总光透射率，该方法生成一个光信号 对标有荧光活动指示剂的神经元区域进行稀疏采样。通过雇用 多个独立的图像路径——每个路径都包含一个具有不同随机排列的掩模 孔径——我们可以生成多个信号，每个信号都反映正在进行的网络活动，但 只是弱相关。我们的初步实验和计算机模拟表明信号 来自四个独立的屏蔽路径可能足以解码由 施加到齿状回输入层的不同刺激。拟议的工作将使用计算机 模拟、全细胞膜片钳记录和光学方法来优化和完善这一点 方法。然后，我们将验证这种新光学方法解码网络状态的能力 大容量荧光 Ca 成像，同时使用多个 细胞内记录。我们使用了基于细胞内记录的检测网络方法 最近出版了四本系列出版物。与之前的这些研究一样，拟议的 实验工作将使用标准的急性啮齿动物脑切片进行。我们相信这一点 该方法在提供电路功能的非侵入性“全电路”视图方面是独一无二的，并且将 在识别特定网络状态和网络状态转换的动态方面特别有用。 该方法还与标准多电极阵列记录和 2 光子 Ca 成像技术。虽然这些方法也可以对大面积的脑组织进行采样， 两种技术（以及传统的细胞外单位记录）的主要目标是估计活性 在单个神经元中。相比之下，我们的方法故意牺牲空间分辨率来生成 具有高信噪比的网络状态特定光信号。由于我们的方法使用 标准 Ca 指示剂染料和单光子激发，一旦 通过所提出的脑切片实验对方法细节进行了完善和验证。