TRANSMISSION OF INFORMATION IN THE VISUAL SYSTEM

所提出的实验试图表征视觉的能力， 用于传送感觉信息的系统。 该方法既在 高水平，通过研究视觉注意力，低水平，通过测量 固有噪声 关于注意力的工作，目标1，解决了“持续时间”问题。 注意力”推测注意力是由一种通用的 数据容量仅为45位的处理器（Verghese和Pelli，1991）。 这将通过测量识别单词的数据容量进行测试 和阅读。 显示器的数据容量将受到模糊的限制 和增加的噪声，以找到最低的数据容量， 阅读。 结果要么证明了注意力范围 推测，通过找到更高的数据容量，或证实它，表明， 阅读速率受视觉注意的固定数据容量的限制。 目标2和3的固有噪声测量借用了 电气工程 噪声将作为视觉刺激呈现， 噪声的测量效果将用于推断 固有噪声，表示为等效输入噪声。 目标2是一个 心理物理学的时空谱的调查 噪声作为亮度和视网膜偏心率的函数， 圆锥体。 目标3是对等效噪声的生理测量， 猫神经节细胞 目标2和3的结果将提供一个全面的 描述固有噪声的特性，然后可以 被纳入视觉敏感度的模型中。

The proposed experiments seek to characterize the capacity of the visual system for transmitting sensory information. The approach is both at a high level, by studying visual attention, and at a low level, by measuring intrinsic noise. The work on attention, Aim 1, addresses the "span of attention" conjecture that attention is mediated by a general-purpose processor with a data capacity of only 45 bits (Verghese and Pelli, 1991). This will be tested by measuring the data capacity for identifying words and reading. The data capacity of the display will be restricted by blur and added noise, to find the lowest data capacity that allows unimpeded reading. The results will either disprove the span-of-attention conjecture, by finding a higher data capacity, or confirm it, showing that reading rate is bounded by the fixed data capacity of visual attention. The intrinsic noise measurements of Aims 2 and 3 borrow a technique from electrical engineering. Noise will be presented as a visual stimulus, and measured effects of that noise will be used to infer the characteristics of the intrinsic noise, expressed as an equivalent input noise. Aim 2 is a psychophysical survey of the spatiotemporal spectrum of the equivalent noise as a function of luminance and retinal eccentricity for rods and cones. Aim 3 is a physiological measurements of the equivalent noise in cat ganglion cells. The results of Aims 2 and 3 will provide a thorough description of the properties of the intrinsic noise, which may then be incorporated into models of visual sensitivity.