Clinatec Institute, Commissariat à l’Energie Atomique, Joseph Fourier University, Grenoble, France.
Prog Brain Res. 2011;194:71-82. doi: 10.1016/B978-0-444-53815-4.00016-9.
Brain-computer interfaces (BCIs) include stimulators, infusion devices, and neuroprostheses. They all belong to functional neurosurgery. Deep brain stimulators (DBS) are widely used for therapy and are in need of innovative evolutions. Robotized exoskeletons require BCIs able to drive up to 26 degrees of freedom (DoF). We report the nanomicrotechnology development of prototypes for new 3D DBS and for motor neuroprostheses. For this complex project, all compounds have been designed and are being tested. Experiments were performed in rats and primates for proof of concepts and development of the electroencephalogram (EEG) recognition algorithm.
Various devices have been designed. (A) In human, a programmable multiplexer connecting five tetrapolar (20 contacts) electrodes to one DBS channel has been designed and implanted bilaterally into STN in two Parkinsonian patients. (B) A 50-mm diameter titanium implant, telepowered, including a radioset, emitting ECoG data recorded by a 64-electrode array using an application-specific integrated circuit, is being designed to be implanted in a 50-mm trephine opening. Data received by the radioreceiver are processed through an original wavelet-based Iterative N-way Partial Least Square algorithm (INPLS, CEA patent). Animals, implanted with ECoG recording electrodes, had to press a lever to obtain a reward. The brain signature associated to the lever press (LP) was detected online by ECoG processing using INPLS. This detection allowed triggering the food dispenser.
(A) The 3D multiplexer allowed tailoring the electrical field to the STN. The multiplication of the contacts affected the battery life and suggested different implantation schemes. (B) The components of the human implantable cortical BCI are being tested for reliability and toxicology to meet criteria for chronicle implantation in 2012. (C) In rats, the algorithm INPLS could detect the cortical signature with an accuracy of about 80% of LPs on the electrodes with the best correlation coefficient (located over the cerebellar cortex), 1% of the algorithm decisions were false positives. We aim to pilot effectors with DoF up to 3 in monkeys.
We have designed multielectrodes wireless implants to open the way for BCI ECoG-driven effectors. These technologies are also used to develop new generations of brain stimulators, either cortical or for deep targets. This chapter is aimed at illustrating that BCIs are actually the daily background of DBS, that the evolution of the method involves a growing multiplicity of targets and indications, that new technologies make possible and simpler than before to design innovative solutions to improve DBS methodology, and that the coming out of BCI-driven neuroprostheses for compensation of motor and sensory deficits is a natural evolution of functional neurosurgery.
目的：我们旨在报告用于新型 3D-DBS 和运动神经假体的原型纳米微技术的开发。对于这个复杂的项目，已经设计了所有的化合物，并正在进行测试。在大鼠和灵长类动物中进行了实验，以证明概念的合理性并开发脑电图（EEG）识别算法。
方法：设计了各种装置。（A）在人体中，设计了一个可编程多路复用器，将 5 个四极（20 个触点）电极连接到一个 DBS 通道，将其双侧植入 2 例帕金森病患者的 STN 中。（B）正在设计一个直径为 50 毫米的钛植入物，远程供电，包括一个无线电组，发射由 64 电极阵列记录的 ECoG 数据，使用专用集成电路，以便植入 50 毫米的环钻开口。通过原始基于小波的迭代 N 路偏最小二乘算法（INPLS，CEA 专利）处理通过无线电接收器接收的数据。植入 ECoG 记录电极的动物必须按下杠杆才能获得奖励。通过使用 INPLS 处理 ECoG 在线检测与杠杆按压（LP）相关的脑签名。这种检测允许触发食物分配器。
结果：（A）3D 多路复用器允许根据 STN 定制电场。触点的倍增影响电池寿命，并提出了不同的植入方案。（B）正在测试人体可植入皮质 BCI 的组件的可靠性和毒理学，以满足 2012 年进行慢性植入的标准。（C）在大鼠中，算法 INPLS 可以检测到大约 80%的 LP 皮层特征，准确性约为 80%电极上的相关系数最好（位于小脑皮层上），算法决策的 1%是假阳性。我们的目标是在猴子中试验自由度高达 3 的效应器。
结论：我们设计了多电极无线植入物，为 BCI-ECoG 驱动的效应器开辟了道路。这些技术还用于开发新一代大脑刺激器，无论是皮质刺激器还是深部刺激器。这一章旨在说明 BCI 实际上是 DBS 的日常背景，该方法的演变涉及目标和适应症的日益多样化，新技术使得设计创新的解决方案来改进 DBS 方法变得更加简单，BCI 驱动的神经假体用于补偿运动和感觉缺陷是功能神经外科的自然演变。
