Population's response to depth ambiguity: Patterns in angle dependence

Abstract

We performed psychophysical measurements to observe patterns in angle dependence of a sample population's response to depth ambiguity generated by three lines having a common vertex. Nineteen respondents classified mixed and randomly arranged sets of images, lacking contextual information, as protrusion or depression. The test images are three lines of uniform length and thickness and with a common vertex, with one or two lines configured in varying angles from the vertical line. For each set of images, the plots (percent of respondents versus angle) of the probability distribution for the classifications of depth showed that there are distinct ranges of angle of the varying line(s) at which majority of the respondents perceive the image as either protrusion or depression. These distributions could be directly related to the distributions of scenes of protrusion/depression being encountered by the sample population.