Tadin Duje, Lappin Joseph S
Vanderbilt Vision Research Center and Department of Psychology, Vanderbilt University, Nashville, TN 37203, USA.
Vision Res. 2005 Jul;45(16):2059-64. doi: 10.1016/j.visres.2005.01.029.
Visual patterns have widely varying contrasts and elicit local signals of varying reliability, ranging from noisy to relatively noise-free. One way to deal efficiently with the variable visual input is to employ flexible neural mechanisms that adapt to changing conditions. We investigated whether the spatial properties of motion mechanisms change with stimulus contrast and found that the optimal size for perceiving motion decreases with increasing contrast. These data were well-described by a model in which spatial summation increases with decreasing contrast.
视觉模式具有广泛不同的对比度，并引发可靠性各异的局部信号，范围从有噪声到相对无噪声。有效处理可变视觉输入的一种方法是采用适应不断变化条件的灵活神经机制。我们研究了运动机制的空间特性是否随刺激对比度而变化，发现感知运动的最佳大小随对比度增加而减小。这些数据通过一个模型得到了很好的描述，在该模型中，空间总和随对比度降低而增加。
