The temporal integration and resolution of velocity signals
The temporal integration and resolution of velocity signals
复制标题
DOI：
10.1016/0042-6989(91)90156-y
复制
发表时间：
1991-12
期刊：
影响因子：
1.8
通讯作者：
R. Snowden;O. Braddick
中科院分区：
文献类型：
--
作者：
R. Snowden;O. Braddick
探讨了人类视觉运动检测的时间特性。实验1测量了速度辨别阈值与刺激持续时间的关系。在大约一段时间内，阈值逐渐下降到约0.06的韦伯分数。100毫秒，速度越快，刺激时间越短。第二个实验要求受试者区分在两种速度之间调制的模式和保持恒定速度的模式。研究发现，做出这一判断所需的最小调制深度在低调制率下相当于0.3的韦伯分数，约为隔离呈现速度时的5倍（见图1）。在某些较高的调制速率下，性能急剧下降。发生这种情况的调制速率随刺激速度而降低，随刺激大小而增加。导出1的结果似乎与主要运动传感器的已知特性一致，而后面的实验结果可能来自整合这些主要运动传感器输出的后期阶段。
The temporal properties of human visual motion detection were explored. Experiment 1 measured thresholds for speed discrimination as a function of stimulus duration. Thresholds fell asymptotically to a Weber fraction around 0.06 over a period of approx. 100 msec, with faster speeds asymptoting at slightly shorter stimulus durations. A second experiment required subjects to discriminate a pattern that was modulated between two speeds from one which remained at a constant speed. The minimum depth of the modulation required to make this judgement was found to be equivalent to a Weber fraction of 0.3 at low modulation rates, around five times greater than when the velocities were presented in isolation (expt 1). At some higher modulation rate performance dramatically declined. The modulation rate at which this occurred decreased with stimulus speed, and increased with stimulus size. The results of expt 1 seem consistent with the known properties of primary motion sensors, while the results of the latter experiments may arise from a later stage integrating the output of these primary motion sensors.