Nelson J I, Kupersmith M J, Seiple W H, Weiss P A, Carr R E
Vision Res. 1984;24(6):579-86. doi: 10.1016/0042-6989(84)90112-3.
Reversing sine wave gratings were electronically swept in spatial frequency and contrast. The acuity limits and contrast thresholds of 4 observers were inferred from evoked potential stimulus-response functions elicited by these stimuli and retrieved with a quadrature lock-in amplifier. The evoked potential functions, linearized in the case of contrast by increasing contrast logarithmically with time, were extrapolated to the point of zero response. This point provides an electrophysiologically defined threshold value for acuity and for contrast. An oblique effect (superior sensitivity for HV-oriented gratings) could reliably be demonstrated in both acuity and contrast threshold performance. This oblique effect could readily be abolished under low spatial/high temporal frequency conditions. The findings are discussed in terms of shifting relative strengths of X and Y contributions to the steady-state evoked potential.
反转正弦波光栅在空间频率和对比度方面进行电子扫描。通过这些刺激引发并由正交锁相放大器获取的诱发电位刺激 - 反应函数，推断出4名观察者的视力极限和对比度阈值。在对比度方面，通过随时间对数增加对比度使诱发电位函数线性化，然后外推到零反应点。该点为视力和对比度提供了电生理学定义的阈值。在视力和对比度阈值表现中均能可靠地证明倾斜效应（对HV方向光栅的更高敏感性）。在低空间/高时间频率条件下，这种倾斜效应很容易消除。根据X和Y对稳态诱发电位贡献的相对强度变化来讨论这些发现。
