CAREER: Electro-optic Multiplexing for Massive Scaling of Neural Recording

我们对外部世界的感知、认知和记忆都是通过大脑来调节的。我们还不完全清楚大脑中的处理过程是如何产生我们丰富的经验的。为了了解神经元的活动如何有助于大脑中信息的转换，以高分辨率记录大脑不同区域的神经信号非常重要。广泛使用的记录神经元活动的工具之一是针形植入式设备，称为神经探针，其穿透组织并具有多个记录位点以捕获大脑中不同神经元的活动。考虑到大脑的复杂性，神经探针上的记录通道数量应该增加，以便从中枢神经系统捕获更多的信号。然而，这是以扩大可植入探针为代价的，对脑组织造成严重损伤。在这个项目中，研究人员的目标是通过设计一种全新的高密度神经探针来打破这种权衡，但这种探针具有非常薄的外形，以揭示大脑功能的神经基础。这将通过使用光来携带来自大脑的记录信号来实现。这种新颖的可扩展技术为高密度神经记录提供了一种独特的方法，可以彻底改变下一代脑机接口的设计，以及减轻癫痫，帕金森病和阿尔茨海默病等脑部疾病的新疗法。该项目为新一代学生提供了一个独特的培训机会，在纳米技术，光子学，该研究项目的技术目标是设计一种新型的高密度神经接口平台，通过直接记录大脑中的电生理活动，并使用精致的电生理编码器将其编码为不同的光波长，石墨烯的光学性质。然后，使用片上硅光子微谐振器对光信号进行密集复用。这种方法将大规模增加可以同时记录的神经元数量，并将提供前所未有的灵敏度和信号保真度。这项多学科研究建立在一系列技术突破的基础上，以利用（i）石墨烯的特殊电光特性将电生理信号编码到光信号上，以及（ii）高质量光子微谐振器的窄带谐振，用于许多记录的神经信号的片上波长域复用。所提出的方法能够同时电光神经记录从成千上万的神经元，而不需要任何外源的光学tages.This奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

Our perception of the outside world, cognition, and memory are all mediated through our brain. It is not yet completely known how processing in the brain gives rise to the richness of our experience. To understand how the activity of neurons contributes to the transformation of information in the brain, it is important to record neural signals across different areas of the brain with high resolution. One of the widely used tools to record neuronal activity is a needle-shaped implantable device, called neural probe that penetrates through the tissue and has multiple recording sites to capture the activity of different neurons in the brain. Given the complexity of brain, the number of recording channels on the neural probe should be increased so that more signals can be captured from the central nervous system. However, this comes at the cost of enlarging the implantable probe, causing severe damage to the brain tissue. In this project, the researchers aim to break this trade-off by designing a completely new class of ultrahigh density neural probes but with a very slim form factor to unravel the neural basis of brain function. This will be enabled by using light to carry the recorded signals from the brain. This novel scalable technology offers a unique approach for high-density neural recording that can revolutionize the design of next generation brain-machine interfaces and also new therapeutics for mitigating brain disorders such as epilepsy, Parkinson’s and Alzheimer’s disease. This project provides a unique training opportunity for a new generation of students in the interdisciplinary field of neural engineering at the interface of nanotechnology, photonics, electronics and neuroscience.The technical goal of this integrative research project is to design a novel ultrahigh density neural interface platform by directly recording the electrophysiology activity in the brain and encoding it into different optical wavelengths using the exquisite electro-optic properties of graphene. The optical signals will then be densely multiplexed using on-chip silicon photonic microresonators. This method will massively scale up the number of neurons which can be simultaneously recorded and will provide unprecedented sensitivity and signal fidelity. This multidisciplinary research builds on a host of technological breakthroughs to leverage (i) the exceptional electro-optic properties of graphene for encoding electrophysiology signals onto optical signals and (ii) the narrowband resonance of high-quality photonic microresonators for on-chip wavelength-domain multiplexing of many recorded neural signals. The proposed method enables simultaneous electro-optic neural recording from thousands of neurons without the need for any exogenous optical tags.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.