Ideal observer for heading judgments
Ideal observer for heading judgments
复制标题
DOI：
10.1016/0042-6989(95)00121-2
复制
发表时间：
1996-02-01
期刊：
影响因子：
1.8
通讯作者：
Banks, MS
中科院分区：
文献类型：
--
作者：
Crowell, JA;Banks, MS
观察情况的几个方面影响从光流确定航向的能力，包括场景中深度变化量和纹理元素的数量，刺激视野的位置和量，以及刺激内扩展焦点的位置。如果不量化提供给观察者的刺激所提供的辨别信息，就不可能确定观察到的表现变化在多大程度上反映了观察者所采用的神经机制和策略的特性。为了能够更好地量化，我们开发了一种从随机点弓形区域区分航向的理想观察者，理想观察者的内部噪声由单点速度辨别实验的结果设置，我们比较了人类和理想观察者在区分视网膜不同部分呈现的不同流动模式(如径向和层流)的标题时的表现，效率-理想阈值与人类阈值的比率-对于不同的流动模式和视网膜偏心率是相当恒定的，这一结果表明，这里考虑的人类观察者根据流型和视网膜轨迹估计航向的能力的变化主要是由于视觉系统测量后刺激提供的分辨信息的变化。在讨论中，我们展示了如何使用理想的观察者来量化任何观察者通过以点表示的任何场景平移的方向辨别信息的空间分布。
Several aspects of the viewing situation affect the ability to determine heading from optical flow, These include the amount of depth variation and number of texture elements in the scene, the location and amount of the visual field stimulated, and the position of the focus of expansion within the stimulus. Without a quantification of the discrimination information provided by the stimuli presented to the observer, it is impossible to determine how much of an observed change in performance reflects the properties of neural mechanisms and strategies employed by the observer. To enable a better quantification, we developed an ideal observer for the discrimination of heading from random-dot bow fields, Internal noises of the ideal observer were set by the results of single-dot velocity discrimination experiments, We compared human and ideal observer performance in discriminating headings with different patterns of flow (e.g. radial vs laminar) presented on different parts of the retina, Efficiency-the ratio of ideal and human thresholds-was fairly constant for the various flow patterns and retinal eccentricities, This outcome indicates that most of the variation in human observers' ability to estimate heading from the flow patterns and retinal loci considered here is due to changes in the discrimination information provided by the stimulus after measurement by the visual system, In the discussion, we show how the ideal observer can be used to quantify the spatial distribution of heading discrimination information for any observer translation through any scene represented by dots.