Lawton T B
Vision Res. 1984;24(2):139-48. doi: 10.1016/0042-6989(84)90099-3.
This study was concerned with the discrimination of multifrequency gratings which differed only in the relative phase of one sinewave component (the test frequency) relative to the other components (the background frequencies). The dependent variable was the contrast of the test frequency required to discriminate between the two gratings. This study found that increasing the test frequency's relative phase difference from 10 to 90 deg significantly increased an observer's contrast sensitivity. However, no overall change in contrast thresholds was measured for test gratings having a relative phase difference between 90 to 180 deg. Moreover, when the mean relative phase was changed from 0 to 45 deg, contrast thresholds did not change when discriminating between gratings having a 90 deg relative phase difference. The type of processing most likely to account for these results in discussed.
本研究关注的是多频率光栅的辨别，这些光栅仅在一个正弦波分量（测试频率）相对于其他分量（背景频率）的相对相位上有所不同。因变量是辨别两个光栅所需的测试频率的对比度。本研究发现，将测试频率的相对相位差从10度增加到90度会显著提高观察者的对比度敏感度。然而，对于相对相位差在90度至180度之间的测试光栅，对比度阈值并未测得总体变化。此外，当平均相对相位从0度变为45度时，在辨别相对相位差为90度的光栅时，对比度阈值没有变化。文中讨论了最有可能解释这些结果的处理类型。
