University of Leuven, Leuven, Belgium.
Behav Res Methods. 2010 Feb;42(1):161-7. doi: 10.3758/BRM.42.1.161.
Orthographic frontal/back projections of biological-motion figures are bistable: The point-light figure in principle can be perceived either as facing toward the viewer or as facing away from the viewer. Some point-light actions--for example, walking--elicit a strong "facing bias": Despite the absence of objective cues to depth, observers tend to interpret the figure as facing toward the viewer in most of the cases. In this article, we present and experimentally validate a technique that affords full experimental control of the perceived in-depth orientation of point-light figures. We demonstrate that by parametrically manipulating the amount of perspective information in the stimulus, it is possible to obtain any desired level of subjective ambiguity. Directions for future research, in which this technique can be fruitfully implemented, are suggested. Program code of a demo is provided that can be modified easily for program code of new experiments. The demo and QuickTime movie files illustrating our perspective manipulation technique may be downloaded from http://brm.psychonomic-journals.org/content/supplemental.
生物运动图形的正字法正面/背面投影是双稳态的：从原则上讲，点光图形可以被感知为面向观察者或背向观察者。一些点光动作——例如，行走——会产生强烈的“面向偏差”：尽管没有客观的深度线索，观察者往往会在大多数情况下将图形解释为面向观察者。在本文中，我们提出并实验验证了一种技术，该技术可以完全控制点光图形的感知深度方向。我们证明，通过参数化地操纵刺激中的透视信息量，可以获得任何所需的主观歧义水平。建议了未来可以成功实施该技术的研究方向。提供了一个演示的程序代码，该代码可以很容易地修改为新实验的程序代码。演示和 QuickTime 电影文件可以从 http://brm.psychonomic-journals.org/content/supplemental 下载，以说明我们的透视操作技术。
