Ruppertsberg Alexa I, Wuerger Sophie M, Bertamini Marco
Department of Psychology, University of Liverpool, Eleanor Rathbone Building, Liverpool, United Kingdom.
Vis Neurosci. 2007 Jan-Feb;24(1):1-8. doi: 10.1017/S0952523807230081.
There is common consensus now that color-defined motion can be perceived by the human visual system. For global motion integration tasks based on isoluminant random dot kinematograms conflicting evidence exists, whether observers can (Ruppertsberg et al., 2003) or cannot (Bilodeau & Faubert, 1999) extract a common motion direction for stimuli modulated along the isoluminant red-green axis. Here we report conditions, in which S-cones contribute to chromatic global motion processing. When the display included extra-foveal regions, the individual elements were large ( approximately 0.3 degrees ) and the displacement was large ( approximately 1 degrees ), stimuli modulated along the yellowish-violet axis proved to be effective in a global motion task. The color contrast thresholds for detection for both color axes were well below the contrasts required for global motion integration, and therefore the discrimination-to-detection ratio was >1. We conclude that there is significant S-cone input to chromatic global motion processing and the extraction of global motion is not mediated by the same mechanism as simple detection. Whether the koniocellular or the magnocellular pathway is involved in transmitting S-cone signals is a topic of current debate (Chatterjee & Callaway, 2002).
现在人们普遍认为，人类视觉系统能够感知颜色定义的运动。对于基于等亮度随机点运动图的全局运动整合任务，存在相互矛盾的证据，即观察者能否（鲁佩茨贝格等人，2003年）或不能（比洛多 & 福贝尔，1999年）为沿等亮度红 - 绿轴调制的刺激提取共同的运动方向。在此我们报告了S视锥细胞有助于彩色全局运动处理的条件。当显示包括中央凹以外的区域、单个元素较大（约0.3度）且位移较大（约1度）时，沿黄 - 紫轴调制的刺激在全局运动任务中被证明是有效的。两个颜色轴的检测颜色对比度阈值远低于全局运动整合所需的对比度，因此辨别与检测比率大于1。我们得出结论，在彩色全局运动处理中有显著的S视锥细胞输入，并且全局运动的提取不是由与简单检测相同的机制介导的。小细胞或大细胞通路是否参与传递S视锥细胞信号是当前争论的一个话题（查特吉 & 卡拉韦，2002年）。
