Zharikova Aleksandra, Gepshtein Sergei, van Leeuwen Cees
Laboratory for Perceptual Dynamics, University of Leuven, Belgium.
Center for Neurobiology of Vision, Salk Institute for Biological Studies, USA.
Vision Res. 2017 Jul;136:1-14. doi: 10.1016/j.visres.2017.04.008. Epub 2017 May 12.
In the course of perceptual organization, incomplete optical stimulation can evoke the experience of complete objects with distinct perceptual identities. According to a well-known principle of perceptual organization, stimulus parts separated by shorter spatial distances are more likely to appear as parts of the same perceptual identity. Whereas this principle of proximity has been confirmed in many studies of perceptual grouping in static displays, we show that it does not generalize to perception of object identity in dynamic displays, where the parts are separated by spatial and temporal distances. We use ambiguous displays which contain multiple moving parts and which can be perceived two ways: as two large objects that gradually change their size or as multiple smaller objects that rotate independent of one another. Grouping over long and short distances corresponds to the perception of the respectively large and small objects. We find that grouping over long distances is often preferred to grouping over short distances, against predictions of the proximity principle. Even though these effects are observed at high luminance contrast, we show that they are consistent with results obtained at the threshold of luminance contrast, in agreement with predictions of a theory of efficient motion measurement. This is evidence that the perception of object identity can be explained by a computational principle of neural economy rather than by the empirical principle of proximity.
在知觉组织过程中，不完整的视觉刺激能够唤起具有独特知觉身份的完整物体的体验。根据一个著名的知觉组织原则，空间距离较短的刺激部分更有可能表现为同一知觉身份的部分。尽管这一接近原则在许多关于静态显示中知觉分组的研究中得到了证实，但我们发现它并不适用于动态显示中物体身份的知觉，在动态显示中，各部分由空间和时间距离分隔。我们使用含多个移动部分且有两种知觉方式的模糊显示：一是两个逐渐改变大小的大物体，二是多个相互独立旋转的小物体。长距离和短距离的分组分别对应于对大物体和小物体的知觉。我们发现，与接近原则的预测相反，长距离分组通常比短距离分组更受青睐。尽管这些效应在高亮度对比度下被观察到，但我们表明它们与在亮度对比度阈值下获得的结果一致，这与有效运动测量理论的预测相符。这证明物体身份的知觉可以用神经经济性的计算原则而非接近的经验原则来解释。
