MICROMACHINED STIMULATING MICROELECTRODE ARRAYS

许多潜在的神经假体，包括视觉，听觉和运动假体，在微电极阵列开发出来之前都是不可行的，这些微电极阵列允许多个小的神经元簇被独立地刺激。该项目将涉及研究和开发能够独立刺激多达512个这样的小细胞群的薄膜微电极阵列。具体而言，这些微电极阵列被设计为在视觉皮层、耳蜗核和腰骶脊髓的多个部位提供微刺激。硅的微加工，结合在微加工结构上的电子电路的集成，允许制造在多个柄上具有多个刺激位点的有源电路微电极。目前正在开发的微电极阵列具有沿沿着8或16个穿透柄放置的64个刺激部位。这些64个位点的二维微电极阵列可以组装成具有512个刺激位点的三维阵列。这些薄膜刺激微电极与更传统的线束微电极相比具有多个优点，用于多部位、高选择性刺激。它们的刺激部位密度至少比线束电极大一个数量级，并且允许刺激部位间隔具有与神经元的尺寸相当的尺寸。该设计提供了电路，该电路允许将用于许多神经刺激部位的体外产生的刺激指令组合成单个信号，然后由植入物上的集成电子器件解码。集成的电子设备还允许阵列设计为集成遥测，从而消除了对系留电缆的需要。

Many potential neural prostheses, including visual, auditory, and motor prostheses, will not be feasible until microelectrode arrays are developed that allow multiple, small clusters of neurons to be independently stimulated. This project will involve research and development on thin-film microelectrode arrays capable of independently stimulating as many as 512 such small clusters of cells. Specifically, these microelectrode arrays are being designed to provide microstimulation at multiple sites in the visual cortex, the cochlear nucleus and the lumbrosacral spinal cord. Micromachining of silicon, combined with integration of electronic circuits on the micromachined structure, permits fabrication of active circuit microelectrodes with multiple stimulating sites on multiple shanks. Microelectrode arrays currently under development have 64 stimulation sites placed along 8 or 16 penetrating shanks. These 64-site, two-dimensional microelectrode arrays can be assembled into a 3-dimensional array with 512 stimulating sites. These thin- film stimulating microelectrodes have several advantages over more conventional wire bundle microelectrodes for multiple site, highly selective stimulation. Their stimulating site density is at least an order of magnitude greater than wire bundle electrodes and permits stimulation site spacing with dimensions comparable to the dimensions of neurons. The designs provide circuitry which permits extracorporeally generated stimulus instructions for many neural stimulating sites to be combined into a single signal and then decoded by integrated electronics on the implant. The integrated electronics also permit the arrays to be designed with integrated telemetry, eliminating the need for tethering cables.