CAREER: Resolving action potentials and high-density neural signals from the surface of the brain

尽管在大脑表面放置电极更简单、更安全，但在大脑/神经接口设计中，大脑表面仍然是一个未开发的前沿领域。脑比？入？大脑。本项目的研究目标是构建并优化一种创新的电极阵列设备，使脑接口设备的分辨率提高1000倍以上。这个目标现在被认为是可能的，因为PI？美国在开发一根电线可以支持650多个电极的电子产品方面取得了突破性的成功。该阵列既可以记录大脑活动，也可以刺激大脑，将有助于研究导致癫痫患者癫痫发作的微妙大脑信号，并开启新的治疗方案。这项技术还将极大地改善瘫痪患者的运动假肢装置、盲人的视觉假肢装置的性能，并促进其他神经系统疾病的新治疗。教育目标是让学生和教师了解脑机接口，提高学生追求STEM本科学位和职业的兴趣。与当地几所高中合作，将创建一个关于神经工程的高中书面科学模块，符合州和国家的科学标准。PI将为高中生物和物理教师开发材料，通过动手实验练习介绍神经工程领域。PI将为来自全州的20名科学教师举办年度研讨会，介绍神经工程领域，并给教师们一个试用实验室材料的机会。该项目的研究目标是通过测量基本的神经接口设计参数来推进和优化这些脑接口，这一目标是由PI最近在有源、柔性电子产品方面的突破性发展推动的，该电子产品将使植入神经接口能够使用不到100根导线对超过65,000个电极进行采样。这些设计参数对电极植入物的信噪比、总信息含量和长期可靠性有重要影响。利用与大鼠音频响应相关的计算模型和实验结果，并与合作者提供的非人类灵长类动物数据进行比较，将研究神经接口设备性能的三个关键方面：1)电极材料和接触尺寸，2)电极间距，以及3)阵列几何形状。植入物的设计使用了与数码相机相同的电子元件，使其具有数百万像素而无需数百万电线，并将大脑接口设备的分辨率提高1000倍以上。本研究计划有三个目标：1)测量皮层表面接触尺寸、材料和阻抗对记录的神经信号特性的影响，包括动作电位的记录；2)通过测量不同长度尺度的神经信号的信息含量，确定满足Nyquist-Shannon空间采样所需的表面电极间距；3)通过在自由活动大鼠体内长期植入表面电极阵列，评估其长期功能和生物相容性，了解影响表面电极阵列长期可靠性的生物和非生物因素。该项目的教育目标是创建一个高中科学模块，包括开发和传播课程资源，以及使用Arduino微控制器进行实验室练习，学生可以记录和显示自己的肌电图（EMG）信号，并用它们来控制视频游戏。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The surface of the brain remains an unexplored frontier in brain/neural interface design, despite the fact that it is simpler and safer to place electrodes ?onto? the brain than ?into? the brain. The research goal of this project is to build and optimize an innovative electrode array device that will improve the resolution of brain interface devices by more than 1000-fold. This goal is now considered possible due to the PI?s breakthrough success in developing electronics that can support more than 650 electrodes with a single wire. The array, which can both record brain activity and stimulate the brain, will enable research into the subtle brain signals that generate seizures in people with epilepsy and unlock new treatment options. The technology will also dramatically improve the performance of motor prosthetic devices for the paralyzed, visual prosthetic devices for the blind, and facilitate new treatments for other neurological disorders. The educational goal is to engage students and teachers in understanding brain-machine interfaces and increase interest among students in pursuing STEM undergraduate degrees and careers. In collaboration with several local high schools, a high-school written science module on neuroengineering, meeting state and national science standards, will be created. The PI will develop materials for high school biology and physics teachers to introduce the field of neuroengineering with a hands-on laboratory exercise. The PI will host an annual workshop for 20 science teachers from around the state to introduce the field of neuroengineering and to give the teachers a chance to try out the lab materials.The project's research objective, driven by the PI's recent breakthrough development of active, flexible electronics that will enable implanted neural interfaces in which greater than 65,000 electrodes can be sampled using fewer than 100 wires, is to advance and optimize these brain interfaces by measuring fundamental neural interface design parameters. These design parameters critically influence the signal to noise ratio, total information content, and long-term reliability of electrode implants. Leveraging both computational models and experimental results related to audio responses in rats and comparisons to nonhuman primate data made available by a collaborator, three aspects critical to the performance of neural interface devices will be investigated: 1) electrode material and contact size, 2) electrode spacing, and 3) array geometry. The implant design uses the same electronics that permit a digital camera to have millions of pixels without millions of wires and will improve the resolution of brain interface devices by more than 1000-fold. The Research Plan is organized under 3 objectives: 1) Measure the effect of cortical surface contact size, material, and impedance on the properties of the recorded neural signals, including the recording of action potentials (APs); 2) Determine the surface electrode spacing required to satisfy Nyquist-Shannon spatial sampling by measuring the information content of neural signals from varying length scales and 3) Understand the biological and non-biological factors that influence the long-term reliability of surface electrode arrays by chronically implanting surface electrode arrays in freely behaving rats and evaluating long-term function and biocompatibility. The project's educational objective, to create a high-school science module, involves development and dissemination of curricular resources and a lab exercise using Arduino microcontrollers that will allow students to record and display their own electromyographic(EMG) signals and use them to control a video game.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.