Wright M J, Johnston A
Vision Res. 1983;23(10):983-9. doi: 10.1016/0042-6989(83)90008-1.
Contrast sensitivity, measured as a function of retinal eccentricity for stimuli differing in temporal and spatial frequency (0.25-9 c/deg; 0-16 Hz, 0-12 degrees eccentricity), was maximum at the fovea and declined linearly with eccentricity. The slope of the decrease depended upon spatial but not temporal frequency. Contrast sensitivity for drifting gratings was approximately twice that for sinusoidal counterphase gratings at all eccentricities. For central viewing log contrast sensitivity increased with grating length. The shape of this function was systematically related to spatial frequency but independent of temporal frequency, indicating that the visual field is homogeneous in sensitivity for change in contrast over time. The implications of these findings for mechanisms of threshold vision in fovea and periphery are discussed.
对比敏感度作为视网膜离心率的函数进行测量，针对在时间和空间频率上不同的刺激（0.25 - 9周/度；0 - 16赫兹，离心率0 - 12度），在中央凹处最大，并随离心率呈线性下降。下降的斜率取决于空间频率而非时间频率。在所有离心率下，漂移光栅的对比敏感度约为正弦反相光栅的两倍。对于中央注视，对数对比敏感度随光栅长度增加。此函数的形状与空间频率系统相关，但与时间频率无关，表明视野在随时间对比度变化的敏感度方面是均匀的。讨论了这些发现对中央凹和周边阈值视觉机制的影响。
