基于磁声电效应的经颅聚焦刺激方法研究

Neurostimulation and regulation are of great significance in brain science research and clinical practice. Existing non-destructive nerve stimulation methods have limitations in insufficiency of focus or low stimulation depth. This project proposes a novel non-invasive brain nerve focused stimulation method based on the Magneto-acousto-electrical effect, which is expected to achieve safe and effective high-precision deep stimulation. In this project, Firstly, we plan to establish the coupling model of magnetic field and acoustic field, use the focused acoustic field to construct the induced electric field, investigate the influence of different focusing modules of acoustic field on the focusing effect of the induced electric field, and establish evaluation indicators and evaluation methods for intracranial induced electric field distribution. Secondly, we want to design skull phantom model experiments, and measure the acoustic pressure of focused acoustic field, the current density of the induced electric field and other parameters, and detect the consistency and safety of the acoustic field and the electric field; Thirdly, we will design animal experiments, record the multi-channel local field potentials (LFPs) of the rat under different focusing degrees and different depths using the implantable microelectrode array, and analyze the time-frequency characteristics and the nonlinear dynamic characteristics of LFPs, and compare the LFPs signal characteristics between the stimulation group rats and the control group rats, explore the proposed non-invasive transcranial Magneto-Acousto-Electric focusing stimulation effect on the brain excitability. The proposed new method may help to provide the basis for a deep understanding of the brain activity regulatory mechanisms with the transcranial Magneto-Acousto-Electric focusing stimulation..The project is expected to achieve breakthroughs in transcranial Magneto-Acousto-Electrical stimulation method and its effects on the regulatory mechanisms of the brain, and it has important research significance and application prospects.

神经刺激与调控对脑科学研究与医学临床具有重要意义，现有无损伤神经刺激手段存在聚焦度或刺激深度不足的局限性。本项目基于磁声电效应提出一种新型无创脑神经聚焦刺激方法，有望实现安全有效地高精度深部刺激。通过建立磁场与声场耦合模型，利用聚焦声场构建感应电场，考察不同聚焦模式对感应电场聚焦效果的影响，建立颅内感应电场分布的评价指标和评价方法；设计仿体模型实验并测量声压和电流密度等参数，检测施加声场与感应电场的一致性及安全性；设计动物实验，记录大鼠不同聚焦度和不同深度刺激诱发的多通道局部场电位(LFPs)，分析LFPs时频特性和非线性动力学特性，研究模型组与对照组大鼠的LFPs信号特征，探索经颅磁声电聚焦刺激作用对大脑神经兴奋性的调控机制，为深入了解新方法及其对脑活动的调节机制提供依据。.本项目期望在经颅磁声电刺激方法及其作用影响脑神经的调节机制方面深入研究并取得突破，该研究具有重要意义和应用前景。

新型精准神经调控方法脑科学、神经工程研究与神经系统疾病临床治疗的重要手段，深入开展对脑功能疾病的发病机制探索并发展先进的干预与治疗技术意义重大。针对目前经颅磁刺激（TMS）和经颅直流表面电刺激（tDCS）等非侵入神经调控技术的分辨率不高及穿透深度小等方面的局限，本项目以电磁学原理、声学理论和神经科学为基础，从电磁场和声场耦合建模与分析、神经电生理等角度，研究高聚焦度感应电场发生机理，考察不同声场聚焦模式下所产生感应电场的聚焦特征；基于磁声电耦合效应，提出新的电场聚焦理论和脑神经刺激方法，实现高分辨率深部脑神经刺激。将所提出刺激方法与在体植入式多通道神经电生理信号记录、脑片膜片钳实验以及光纤光度检测技术相结合，记录分析被刺激啮齿类动物的神经响应，刻画刺激后大脑的动态反应过程，进行响应信号的时频域分析和非线性动力学等分析，实施了经颅磁声电刺激动物实验功效研究。实验结果表明，经颅磁声电刺激对神经元和神经元集群放电活动影响显著，可有效改变被刺激动物的神经活性，并深入探究了磁声电刺激对啮齿类动物脑神经调控的作用机理。本项目所提出的新型脑神经刺激方法兼具经颅超声刺激和TMS两者的优点，具有高分辨率和高刺激深度，同时大幅提高了诱发电场控制的灵活性，实现了在较低的超声剂量刺激下，产生安全有效的神经调控作用，研究结果可助力推进我国脑计划的实施和相关脑功能疾病的发病机制的深入探索，并为相关脑科学与类脑智能的研究、脑疾病治疗和康复提供高精度多物理场耦合干预手段，具有重要的科学意义和临床应用价值。