微型全植入分布式神经信号记录系统关键技术研究

The brain science research based on neural signal recording, an important research content of “Brain Projects” in China and the United States, is of great significance to the treatment of neurological diseases and revealing the complex links of brain function and behavior. In order to solve the problems of spatial resolution, spatial coverage and short-term existence in current neural signal recording systems, this project proposes a fully micro-implanted and distributed neural signal recording system based on wireless power and signal transmission. It can realize chronically recording neuronal activity (EAP and LFP signals) in multi brain regions. In order to energize the distributed and small implants wirelessly, we will study the modelling and optimization of power transmitting coil array to generate omnidirectional and homogeneous magnetic fields in the volume of the implants, and the modeling, design, and optimization of 3D power receiving coils with the power management circuits under the limits of the millimeter size in brain. In order to ensure the wireless signal transmission, we study the methods of signal transfer between multi distributed coils (antennas) and the signal coil array, and the design of the coils to attenuate the interference of wireless power transmission. A low-power, low-noise, and compact integrated circuit chip is designed and then micro-packaged with the coils and electrodes under millimeter-size restriction. Finally, a prototype of the proposed novel neural signal recording system is verified in vitro.

以神经信号记录为基础的脑科学研究对治疗神经疾病、揭示大脑功能和行为的复杂联系具有重要意义，是中美两国脑计划的重要研究内容。为解决当前神经信号的记录中存在空间分辨率、空间覆盖面以及短期性的问题，本项目提出基于无线能量和信号传输的微型全植入、分布式神经信号记录系统，可以实现多区域、长期记录神经元活动（EAP和LFP信号）的目标。研究可以在微型植入器件分布空间内产生各向、均匀磁场的能量发送线圈阵列的建模和优化方法，以及脑内毫米尺寸限制下3D能量接收线圈和电源管理电路的建模、设计和优化，解决无线能量供应的问题；研究多个分布式植入器件在无线能量传输干扰下的信号传输方式和线圈（天线）设计方法，解决无线信号传输的问题；研究毫米尺寸下线圈、芯片、电极的微组装和低功耗、低噪声、低面积神经信号记录芯片的设计，完成系统原型的设计，并进行离体实验验证。

以神经信号记录为基础的脑科学研究对治疗神经疾病、揭示大脑功能和行为的复杂联系具有重要意义，是中美两国脑计划的重要研究内容。为解决当前神经信号的记录中存在空间分辨率、空间覆盖面以及短期性的问题，本项目提出基于无线能量和信号传输的微型全植入、分布式神经信号记录系统，可以实现多区域、长期记录神经元活动（EAP和LFP信号）的目标。对此，本项目重点开展了如下两方面的研究工作：（1）在无线供电技术上，提出了带有磁芯的毫米尺寸植入式螺旋线圈的解析建模和优化工作；提出了三相三层发送线圈阵列的设计和优化，解决了分布式植入系统的能量供应问题；提出了双接收线圈同步和异步工作模式的电流型结构无线供电方法，减小了微弱接收电压下整流损耗。（2）在系统层面，实现了基于蓝牙和无线供电的无线无源神经信号记录系统、刺激系统，以及同时包含记录和刺激的闭环系统原型，其大小为10mm*10mm，可记录EAP和LFP神经信号，也可产生幅值和频率可调的神经刺激信号。在研究过程中，参加了多次领域内国际会议，并与佐治亚理工学院教授Maysam Ghovanloo教授开了较为深入的合作。目前，已发表期刊论文14篇，其中SCI检索论文8篇，会议论文8篇，授权发明专利10项，出版专著1本，获得学会/协会成果奖二等奖1项，培养毕业硕士研究生10人。