Lánský P, Yakimoff N, Radil T
Biol Cybern. 1987;56(5-6):389-96. doi: 10.1007/BF00319518.
Two-dimensional normally distributed random dot patterns were used in two experiments on visual orientation estimation. In the first experiment the patterns differed in their sample correlation and in dot number. In the second one the number of dots was maintained constant but the patterns were generated as a superposition of two normally distributed orthogonal sets composed of different number of dots. In both experiments the estimated orientation depended on stimuli correlation - with increasing correlation the estimated orientation gets closer to the orientation of the least square distance axis of the pattern. Even at very low unsignificant correlations there still remained a hint about stimulus orientation which was not estimated at random. Equalizing consecutively the number of dots in the two orthogonal dot patterns during the second experiment did not result in chance performance either. The bimodal angular distributions of the obtained responses permitted to approach the problem of orientation ambiguity. The results are discussed in terms of optimization processes taking place in the visual system.
在两项关于视觉方向估计的实验中使用了二维正态分布随机点图案。在第一个实验中，图案在样本相关性和点数方面有所不同。在第二个实验中，点数保持恒定，但图案是由两个由不同点数组成的正态分布正交集叠加生成的。在这两个实验中，估计的方向都取决于刺激相关性——随着相关性增加，估计的方向更接近图案最小二乘距离轴的方向。即使在非常低的无显著意义的相关性下，仍然存在关于刺激方向的线索，而不是随机估计的。在第二个实验中连续使两个正交点图案中的点数相等也没有导致随机表现。所获得反应的双峰角度分布有助于解决方向模糊性问题。根据视觉系统中发生的优化过程对结果进行了讨论。
