一項研究發(fā)現(xiàn),，科研人員可能距離恢復(fù)盲人視覺的修復(fù)裝置更近了一步。該研究發(fā)現(xiàn)當猴子的大腦的一部分區(qū)域受到電刺激的時候猴子能看到東西,。
Peter Schiller及其同事向兩只恒河猴的主視覺皮層植入了微電極,。通過這些微電極，這組科研人員對正在進行兩個任務(wù)的這些猴子的大腦進行了電刺激,。對于第一個任務(wù),，這些猴子被促使著把他們的眼睛轉(zhuǎn)向更明亮和更大的兩個目標，其中一個被周期性的電刺激取代,。
正確地執(zhí)行了這個任務(wù)的猴子獲得了蘋果汁的獎勵,。
為了確定猴子觀察到的顏色，這組科研人員在一個目標或者電刺激出現(xiàn)之前改變了背景圖像,。 當背景與電刺激產(chǎn)生的圖像有同樣的顏色和對比度的時候,，這些猴子無法看到目標而且沒有轉(zhuǎn)動它們的目光。
這組作者說,，這些發(fā)現(xiàn)可能有助于闡明電刺激產(chǎn)生的圖像的尺寸,、對比度和顏色,，讓科研人員能夠評估修復(fù)裝置的有效性和壽命。（生物谷 Bioon.com）
doi:10.1073/pnas.1108337108
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New methods devised specify the size and color of the spots monkeys see when striate cortex (area V1) is electrically stimulated
Peter H. Schiller, Warren M. Slocum, Michelle C. Kwak, Geoffrey L. Kendall, and Edward J. Tehovnik
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.
