Visual Form Perception Produced by Electrically Stimulating Human Visual Cortex

项目摘要/摘要 失明使全世界数百万人致残。在大多数情况下，无法治愈 失明是由眼睛、视网膜或视神经的损伤或功能障碍引起的， 但视觉皮质没有受损，而且有潜在的功能。电气 刺激视皮层，即使是在盲人患者中，也会产生一种 被称为膦的独特的光点。长期以来，人们一直对 开发一种使用直接激活完整视觉的假体装置 大脑皮层可以恢复盲人的视力。据推测，膦类化合物 可以作为盲人视力恢复的基础；但不同于 在视频显示器中，多个膦元素不容易组合成 对连贯形式的感知。我们提出了一种新的刺激范式，称为 “动态电流转向”，可以极大地提高视觉能力 皮质假体(VCP)，以产生有用的视觉形式感知。因为 在接下来的几年内有几个VCP的临床试验的迫在眉睫的计划 几年来，现在是开发改进方法的一个特别重要的时刻 用于刺激视皮层。评估和改进动态电流转向，如 VCP的方法论，我们将测量这部小说产生的知觉 人类癫痫患者植入植入物的临床前测试范式 颅内电极。在目标1中，我们将测试动态电流控制作为一种新的 用于产生视觉形式的感知的方法。在目标2中，我们将优化 动态电流转向组件，以促进对连贯形式的感知。 这些目标加在一起，将产生一种产生有用感知的新范式 通过刺激视觉皮质来形成连贯的视觉形式 可在下一代VCP的即将进行的临床试验中翻译。

Project Summary/Abstract Blindness disables millions of people across the world. In most cases, incurable blindness is caused by damage or dysfunction of the eye, retina, or optic nerve, but the visual cortex is undamaged and potentially functional. Electrical stimulation of visual cortex, even in blind patients, produces a percept of a distinct spots of light known as phosphenes. There has long been interest in developing a prosthetic device that employs direct activation of the intact visual cortex to restore vision to the blind. It has been speculated that phosphenes could serve as the building blocks for visual restoration in the blind; but unlike pixels in a video display, multiple phosphenes are not readily combined into a percept of a coherent form. We propose a novel stimulation paradigm, termed "dynamic current steering," that can dramatically enhance the ability of visual cortical prosthetics (VCPs) to produce useful percepts of visual forms. Because there are imminent plans for clinical trials of several VCPs within the next few years, now is a currently particularly important time to develop improved methods for stimulation of visual cortex. To assess and refine dynamic current steering as a methodology for a VCP, we will measure percepts produced with this novel paradigm in pre-clinical testing in human epilepsy patients with implanted intracranial electrodes. In Aim 1, we will test dynamic current steering as a novel method for producing percepts of visual forms. In Aim 2, we will optimize the components of dynamic current steering to promote perception of coherent forms. Together, these aims will result in a novel paradigm for producing useful percepts of coherent visual forms by stimulation visual cortex that will be immediately translatable in forthcoming clinical trials of the next generation of VCPs.