Howard Ian P
Centre for Vision Research, York University, 4700 Keele Street, Toronto, Ontario, Canada M3J 1P3.
Spat Vis. 2008;21(6):581-92. doi: 10.1163/156856808786451417.
It is known that the vergence state of the eyes can serve as a cue to distance. However, it has been claimed that changes in vergence induced by modulations of the binocular disparity of a random-dot display do not create a sensation of motion in depth. The present experiment tests the hypothesis that modulation of binocular disparity in a random-dot display does not create a sensation of motion in depth because, in such a display, looming of the image that normally accompanies motion in depth is absent. The image of a radial pattern remains self-similar when it moves in depth, so the absence of looming in such an image should not inhibit the effects of modulation of disparity. Subjects tracked with unseen hand the perceived motion in depth created by modulations of the disparity of a display of random spots, a single spot, and a radial pattern. As previously reported, the random-spot display produced almost no motion in depth. However, the single spot and the radial pattern produced motion in depth. It is concluded that modulations of vergence and/or of absolute disparity can create a sensation of motion in depth when the effects of looming are weakened or removed. However, strong sensations of motion in depth of isolated objects require the presence of looming.
众所周知，眼睛的聚散状态可作为距离的线索。然而，有人声称，由随机点显示的双眼视差调制引起的聚散变化不会产生深度运动的感觉。本实验检验了以下假设：随机点显示中的双眼视差调制不会产生深度运动的感觉，因为在这种显示中，通常伴随深度运动的图像逼近不存在。当径向图案的图像在深度上移动时，它仍然是自相似的，因此这种图像中不存在逼近不应抑制视差调制的效果。受试者用未被看见的手跟踪由随机点显示、单个点和径向图案的视差调制所产生的深度感知运动。如先前报道的那样，随机点显示几乎没有产生深度运动。然而，单个点和径向图案产生了深度运动。得出的结论是，当逼近的效果被削弱或消除时，聚散和/或绝对视差的调制可以产生深度运动的感觉。然而，孤立物体强烈的深度运动感觉需要存在逼近。
