最近一项研究可能让科研人员距离恢复盲人视觉的修复装置更近了一步。这项研究发现当猴子的大脑的一部分区域受到电刺激的时候猴子能看到东西。
灵长类动物的视觉皮质
Peter Schiller及其同事向两只恒河猴的主视觉皮层植入了微电极。通过这些微电极，这组科研人员对正在进行两个任务的这些猴子的大脑进行了电刺激。对于第一个任务，这些猴子被促使着把他们的眼睛转向更明亮和更大的两个目标，其中一个被周期性的电刺激取代。正确地执行了这个任务的猴子获得苹果汁的奖励。为了确定猴子观察到的颜色，这组科研人员在一个目标或者电刺激出现之前改变了背景图像。 当背景与电刺激产生的图像有同样的颜色和对比度的时候，这些猴子无法看到目标而且没有转动它们的目光。这组作者说，这些发现可能有助于阐明电刺激产生的图像的尺寸、对比度和颜色，让科研人员能够评估修复装置的有效性和寿命。
相关英文论文摘要：
New methods devised specify the size and color of the spots monkeys see when striate cortex (area V1) is electrically stimulated
Creating a prosthetic device for the blind is a central future task. Our research examines the feasibility of producing a prosthetic device based on electrical stimulation of primary visual cortex (area V1), an area that remains intact for many years after loss of vision attributable to damage to the eyes. As an initial step in this effort, we believe that the research should be carried out in animals, as it has been in the creation of the highly successful cochlear implant. We chose the rhesus monkey, whose visual system is similar to that of man. We trained monkeys on two tasks to assess the size, contrast, and color of the percepts created when single sites in area V1 are stimulated through microelectrodes. Here, we report that electrical stimulation within the central 5° of the visual field representation creates a small spot that is between 9 and 26 min of arc in diameter and has a contrast ranging between 2.6% and 10%. The dot generated by the stimulation in the majority of cases was darker than the background viewed by the animal and was composed of a variety of low-contrast colors. These findings can be used as inputs to models of electrical stimulation in area V1. On the basis of these findings, we derive what kinds of images would be expected when implanted arrays of electrodes are stimulated through a camera attached to the head whose images are converted into electrical stimulation using appropriate algorithms.
英文论文链接：https://www.pnas.org/content/early/2011/10/04/1108337108.abstract
