空间频率随机变化的正弦波光栅的定向敏锐度。

Orientation acuity for sine-wave gratings with random variation of spatial frequency.

作者信息

Heeley D W, Buchanan-Smith H M, Heywood S

机构信息

Department of Psychology, University of St Andrews, Fife, Scotland.

出版信息

Vision Res. 1993 Dec;33(17):2509-13. doi: 10.1016/0042-6989(93)90131-f.

DOI:10.1016/0042-6989(93)90131-f

PMID:8249331

Abstract

Orientation discrimination thresholds were estimated for sine-wave grating stimuli using a two-alternative forced-choice procedure on the two principal, and the two main oblique axes. The two discriminanda within any trial were subject to independent random variation of their spatial frequency. The variation of spatial frequency was defined by a Gaussian probability density function. Thresholds were obtained for five different depths of frequency variation within the range 0.0-1.0 octave. We find that orientation acuity on any of the axes tested is unaffected by variation in the spatial frequency of the targets. The data support the hypothesis that orientation and spatial frequency are independent and orthogonal neural codes.

摘要

使用二择一的强迫选择程序，在两个主要轴和两个主要斜轴上估计正弦波光栅刺激的方向辨别阈值。任何一次试验中的两个辨别刺激在空间频率上独立随机变化。空间频率的变化由高斯概率密度函数定义。在0.0至1.0倍频程范围内获得了五个不同频率变化深度的阈值。我们发现，在任何测试轴上的方向敏锐度不受目标空间频率变化的影响。这些数据支持了方向和空间频率是独立且正交的神经编码这一假设。