Takei Shigekazu, Nishida Shin'ya
Interdisciplinary Graduate School of Science and Engineering, Tokyo Institute of Technology, Kanagawa, Japan.
J Vis. 2010 Apr 29;10(4):23.1-15. doi: 10.1167/10.4.23.
Cognitive ambiguity, such as found in categorical judgments, increases behavioral response latency. Here we examined whether perceptual ambiguity for bistable stimuli, stimuli in which two perceptual interpretations were mutually competitive, also increased perceptual latency. We presented a bistable stimulus and measured the observer's reaction time to judge which of two possible percepts was seen. Perceptual ambiguity was systematically manipulated and how it affected the response latency was examined. The first experiment used a motion-defined rotating cylinder. The observers judged the rotation direction, and the perceptual ambiguity was controlled by binocular disparity. The second experiment used Rubin's vase. The observers judged whether the figure was a vase or faces, and the perceptual ambiguity was controlled by luminance of the surround. In both experiments, we found that the perceptual ambiguity caused only a small or no increase in reaction time and, presumably, in the perceptual latency included in the reaction time. These findings suggest that perceptual competition does not have a strong effect on the latency of the initial perception of bistable stimuli. Given that many perceptual problems are under-constrained as in the cases of bistable stimuli, it is presumably ecologically functional for the brain to establish perception as quickly as possible regardless of the presence of potential alternatives.
认知模糊性，如在分类判断中所发现的，会增加行为反应潜伏期。在此，我们研究了双稳态刺激（即两种知觉解释相互竞争的刺激）的知觉模糊性是否也会增加知觉潜伏期。我们呈现了一个双稳态刺激，并测量观察者判断看到的是两种可能知觉中的哪一种的反应时间。系统地操纵了知觉模糊性，并研究其如何影响反应潜伏期。第一个实验使用了运动定义的旋转圆柱体。观察者判断旋转方向，知觉模糊性由双眼视差控制。第二个实验使用了鲁宾之瓶。观察者判断图形是花瓶还是面孔，知觉模糊性由周围环境的亮度控制。在两个实验中，我们发现知觉模糊性仅导致反应时间有少量增加或没有增加，并且推测在反应时间中包含的知觉潜伏期也没有增加。这些发现表明，知觉竞争对双稳态刺激初始知觉的潜伏期没有强烈影响。鉴于许多知觉问题如双稳态刺激的情况一样是约束不足的，大脑尽快建立知觉而不管潜在替代物的存在，这大概在生态上是有功能的。
