Progress in human visual evoked responses.
Progress in human visual evoked responses.
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DOI：
10.1097/00004691-198401000-00004
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发表时间：
1984
期刊：
影响因子：
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通讯作者：
P. Gouras
中科院分区：
文献类型：
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作者：
P. Gouras
过去几十年来，对人类受试者无创检测视觉诱发反应的研究不断取得进展，但 Celesia（1984 年；本期）之前的评论中引用的一些最新发现加剧了该领域的兴奋程度。这一领域的进展主要归功于三个因素。其中之一是电子计算机的引入，大大提高了检测这些反应的灵敏度以及进一步分析它们的速度。第二个是电光技术的发展，它有助于呈现复杂的视觉刺激，例如不同尺寸和方向的反转或漂移正弦波或方波光栅或棋盘状配置，其中可以在这些刺激的轮廓上独立控制亮度对比度。我们即将能够常规使用彩色显示器，其中人类视觉的最终变量色度（色调和饱和度）也可以在这些轮廓上相互独立且独立于亮度进行控制。最后但并非最不重要的因素是在动物视觉系统上进行的单神经元电生理学的背景。这项工作产生的影响人类视觉诱发反应研究的主要概念是认识到单个神经元会被极其特定的刺激所激发。只有当视觉刺激经过精确设计时，一个或一组神经元才会开启（去极化），而许多其他神经元组会关闭（超极化）。对于一组来说是完美的刺激对于另一组来说却是不完美的。视觉空间的每个区域都由从视网膜开始并在更高视觉中心数量倍增的单独神经元子集并行分析。视觉诱发反应能够凭借视觉刺激的正确设计来捕获这些不同神经元子集的信号。视觉诱发反应的信息内容的关键不在于反应本身，而在于用于产生该反应的刺激。必须投入更多的时间来仔细分析刺激结构而不是反应结构。最近，通过修改传统刺激以引发最早研究和最大的视觉诱发反应之一——电刺激，从视网膜最内层神经元获取信息方面取得了重要突破。
Research in visual evoked responses detectable noninvasively from human subjects has made continuous progress over the past several decades, but some recent discover-ies cited in the previous review of Celesia (1984; this issue) have intensified the level of excitement in this field. Progress in this field has been due mainly to three factors. One has been the introduction of electronic computers which greatly enhanced the sensitivity for detecting these responses and the rapidity with which they can be further analyzed. A second has been the development of electro-optical technology which facilitates the presentation of sophisticated visual stimuli, such as reversing or drifting sinusoidal or square wave gratings of different sizes and orientations or checkerboard-like configurations in which luminance contrast can be independently controlled across the contours of these stimuli. We are on the verge ofbeing able touse routinely color displays in which the ultimate variables in human vision, chrominance (hue and saturation), can also be controlled across these contours independently of each other and of luminance. The last but not the least important factor has been the background of single-neuron electrophysiology carried out on the visual system of animals. The major concept derived from this work to influence human visual evoked-response research has been the realization that single neurons are excited by extremely specific stimuli. Only when the visual stimulus is precisely designed will a neuron or a set of neurons turn on (depolarize) while many other sets turn off (hyperpolarize). What is a perfect stimulus for one set is imperfect for another. Each area ofvisual space is analyzed in parallel by separate subsets of neurons beginning in the retina and multiplyingin number in higher visual centers. The visual evoked response is capable of capturing the signals of these different subsets of neurons by virtue of the proper design of the visual stimulus. The key to the informational contentofa visual evoked response lies less in the responseitselfthan in the stimulus used to generate this response. Much more time must be devoted to carefully analyzing the stimulus structure rather than the response structure. An important breakthrough has recently been made in obtaining information from neurons in the innermost layers of the retina by modifying the traditional stimulus for eliciting one of the earliest researched and largest visual evoked response, the electro-