MacVeigh D, Whitaker D, Elliott D B
Department of Vision Sciences, Aston University, Birmingham, UK.
Ophthalmic Physiol Opt. 1991 Jan;11(1):76-80.
The effect of line length on displacement threshold hyperacuity at various levels of contrast was investigated. At high contrasts there was no significant effect of line length, but as contrast was reduced thresholds for shorter line lengths increased rapidly. Thresholds at longer line lengths demonstrated a form of contrast saturation which differed from vernier acuity whose thresholds increased consistently with a reduction in contrast. As line length in the displacement threshold task was reduced, the amount of contrast saturation became less and displacement thresholds therefore resembled the contrast response of vernier acuity. Results are explained in terms of spatial summation along the length of the lines, the effects of which depend upon the spatial configuration of the hyperacuity stimulus under consideration.
研究了线条长度对不同对比度水平下位移阈值超敏锐度的影响。在高对比度时，线条长度没有显著影响，但随着对比度降低，较短线条长度的阈值迅速增加。较长线条长度的阈值表现出一种对比度饱和形式，这与游标敏锐度不同，游标敏锐度的阈值随着对比度降低而持续增加。在位移阈值任务中，随着线条长度缩短，对比度饱和量减少，因此位移阈值类似于游标敏锐度的对比度响应。结果根据沿线条长度的空间总和来解释，其效果取决于所考虑的超敏锐度刺激的空间配置。
