Ultra High-density Optomechanic Neural Interfaces

超高密度光机械神经接口

• 批准号: 10463818
• 负责人: Maysamreza Chamanzar
• 金额: $ 21.06万
• 依托单位: CARNEGIE-MELLON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2024-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10463818
• 关键词: Adverse effects; Animal Model; Animals; Area; Brain; Brain region; Cells; Characteristics; Consumption; Coupled; Custom; Devices; Disease; Electric Stimulation; Electrodes; Elements; Epilepsy; Functional disorder; Future; Generations; Goals; Health; Hippocampus (Brain); Human; Immune signaling; Intervention; Investigation; Light; Mechanics; Membrane; Methods; Microfabrication; Monitor; Motion; Mus; Neurons; Noise; Onset of illness; Optics; Parkinson Disease; Performance; Process; Resolution; Scheme; Signal Transduction; Slice; Surface; System; Techniques; Technology; Testing; Time; Transducers; Translating; Travel; Tungsten; awake; base; cohesion; density; design; experimental study; extracellular; in vivo; innovation; instrument; manufacturability; neural circuit; neural implant; neurotransmission; novel; novel therapeutics; photonics; preservation; relating to nervous system; response; scale up; sensor; simulation; spatiotemporal; tool; waveguide

Project Summary A multi-scale, mechanistic understanding of neural circuits that includes both local- and whole-brain interconnections still remains elusive. One of the fundamental challenges is the lack of tools for monitoring, with high spatiotemporal resolution, the activity of local neuron ensembles simultaneously in different regions of the brain in awake, freely-behaving animals. This calls for the design of ultrahigh density neural probes capable of recording from thousands of neurons with high spatiotemporal resolution. While there has been tremendous progress on the design of conventional passive and active electronic neural probes, these technologies are reaching scaling limits. We need to break away from the conventional scheme of recording and relaying electrical neural signals using passive or active electronic neural probes to enable breakthrough improvements in the number of simultaneous channels that we can record from the brain. Here, we propose a disruptive approach based on fundamental advancements in optics and microelectromechanical systems (MEMS) to deliver an innovative opto-mechanical probe that can potentially have more than a couple of thousand simultaneously active recording electrodes in the same footprint of a conventional passive probe. All of the recorded neural signals in our design are encoded in the optics domain to leverage the ultrahigh bandwidth of light for communicating the recorded aggregate neural signals to outside the brain on a single optical waveguide. In this scheme, each recording channel is encoded onto a single wavelength of light that travels along the same waveguide. This wavelength domain multiplexing (WDM) method enables a true simultaneous recording of many channels, unlike the time domain multiplexing (TDM) scheme that is used in active electronic neural probes, which relies on sequential recording of multiple channels. Therefore, our design enables massive scaling of the number of simultaneously recorded channels, while enhancing SNR, preserving the bandwidth, and minimizing adverse effects of active electronic neural probes such as heat generation inside the brain. The core unit cell of our neural probe is an electromechanical sensor that detects electrical neural signals and converts them to small mechanical motions of a membrane, which in turn modulates a photonic microresonator. Therefore, the electrical neural signal is transformed to a mechanical and then an optical signal. The ultra-high quality factor optical microresonator enhances the detected signals. A single common waveguide coupled to multiple microresonators carries the optical signals to the backend outside the brain. This novel design enables massive scaling of the number of recording channels without increasing the size of the neural probe. Moreover, the conversion of electrical signals to optical signals results in enhanced signal-to-noise ratio (SNR) and also makes the transmitted signals immune to unwanted electrical interference. After successful demonstration of multiplexed electro-opto-mechanic neural recording in this project, the results can be extended in future efforts to i) develop even much higher density neural probes with more than 1000 channels and ii) demonstrate its in vivo application.

项目摘要 对包括局部和全脑的神经回路的多尺度机械理解 互连仍然难以捉摸。根本挑战之一是缺乏监视工具， 高时空分辨率，同时在不同区域的局部神经元合成的活性 醒着，自由地行为的动物。这需要设计超高密度神经探针的设计 从数千个具有高时空分辨率的神经元记录。虽然有很多 传统的被动和主动电子神经探针设计的进展，这些技术是 达到缩放限制。我们需要摆脱传统的记录和中继电气方案 使用被动或主动电子神经探针的神经信号可实现突破性的改进 我们可以从大脑记录的同时通道数量。在这里，我们提出了一种破坏性的方法 基于光学和微电机电系统（MEMS）的基本进步 创新的光学探针可能同时拥有超过几千 在常规被动探针的相同足迹中有效记录电极。所有记录的神经 我们的设计中的信号在光学域中编码，以利用超高带宽的光线 将记录的骨料神经信号传达到单个光学波导上的大脑外部。在这个 方案，每个记录通道都被编码到沿着同一光线传播的单个光波长 波导。此波长域多路复用（WDM）方法可以同时记录许多 与活性电子神经探针中使用的时域多路复用（TDM）方案不同，通道 这取决于多个通道的顺序记录。因此，我们的设计实现了大规模的缩放 同时记录的频道数量，同时增强SNR，保留带宽并最小化 主动电子神经探针的不利影响，例如大脑内部的热产生。核心单元 我们的神经探针是一种机电传感器，可检测到电信号并将其转换为小 膜的机械运动又调节光子微孔子。因此，电气 神经信号转换为机械信号，然后转换为光学信号。超高质量因子光学因素 微孔子增强了检测到的信号。单个公共波导耦合到多个微孔子 将光学信号带到大脑外的后端。这种新颖的设计实现了大规模的缩放 记录通道的数量，而没有增加神经探针的大小。而且，转换 与光学信号的电信号可提高信噪比（SNR），还使得 传输信号免受不需要的电干扰。成功演示了多元 在该项目中，电动机电神经记录，可以在未来的努力中扩展结果i） 甚至具有1000多个通道的更高密度神经探针，ii）证明其体内应用。