Annu Int Conf IEEE Eng Med Biol Soc. 2021 Nov;2021:5733-5736. doi: 10.1109/EMBC46164.2021.9629693.
Cortical vision prostheses are being developed to restore sight in blind patients. Existing electrode arrays that electrically stimulate cortical tissue to artificially induce neural activity are difficult to position directly next to each other. Leaving space between implants creates gaps in the visual field where no visual percepts can be created. Here, we propose current steering as a solution to elicit a neural response between physical electrode locations. We assessed the centroid of neural activity produced by dual-electrode stimulation in the visual cortex of Sprague-Dawley rats. We determined that this centroid could be shifted between physical electrodes by altering the ratio of charge delivered to each electrode. This centroidal shift could enable better environmental perception for cortical implant patients by creating a complete visual field representation while maintaining safe array spacing.
皮质视觉假体正在被开发出来，以恢复盲人的视力。现有的电极阵列通过电刺激皮质组织来人为地诱导神经活动，它们很难彼此直接相邻排列。在植入物之间留出空间会在视野中产生无法产生视觉感知的间隙。在这里，我们提出电流引导作为解决办法，以在物理电极位置之间产生神经响应。我们评估了双电极刺激在 Sprague-Dawley 大鼠视觉皮层中产生的神经活动的质心。我们确定，通过改变每个电极的电荷量的比例，可以在物理电极之间移动这个质心。这种质心的移动可以通过创建一个完整的视觉场表示来实现，同时保持安全的阵列间隔，从而为皮质植入患者提供更好的环境感知。
