TRANSMISSION OF INFORMATION IN THE VISUAL SYSTEM

拟议中的实验试图描述视觉的能力 用于传输感官信息的系统。这种方法既是在一个 高水平，通过研究视觉注意力，在低水平，通过测量 本征噪声。关于注意力的工作，目标1，涉及到 注意力“猜想，注意力是由一个通用的 数据容量只有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来进行测试 还有读书。显示器的数据容量将受到模糊的限制 并增加了噪声，以找到允许畅通无阻的最低数据容量 阅读。结果要么证明注意力的范围是错误的 猜想，通过寻找更高的数据容量，或确认它，表明 阅读速度受视觉注意的固定数据容量的限制。 AIMS 2和AIMS 3的本征噪声测量借鉴了以下技术 电气工程专业。噪音将以视觉刺激的形式呈现，并且 该噪声的测量效果将被用来推断 本征噪声，表示为等效输入噪声。目标2是一个 等效物时空谱的心理物理测量 视杆细胞和视网膜的噪声作为亮度和视网膜偏心率的函数 圆锥体。目标3是对人体等效噪声的生理测量 猫神经节细胞。目标2和目标3的结果将提供全面的 对本征噪声的属性的描述，然后可以 整合到视觉敏感度模型中。

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.