Sakano Yuichi, Allison Robert S
Universal Communication Research Institute, National Institute of Information and Communications Technology, Keihanna Science City, Kyoto, Japan Center for Information and Neural Networks, National Institute of Information and Communications Technology, and Osaka University, Suita City, Osaka, Japan.
Centre for Vision Research, York University, Toronto, ON, Canada.
J Vis. 2014 Jul 24;14(8):21. doi: 10.1167/14.8.21.
There are at least two possible binocular cues to motion-in-depth, namely disparity change over time and interocular velocity differences. There has been significant controversy about their relative contributions to the perception of motion-in-depth. In the present study, we used the technique of selective adaptation to address this question. In Experiment 1, we found that adaptation to motion-in-depth depicted by temporally correlated random-dot stereograms, which contained coherent interocular velocity difference, produced motion aftereffect in the depth direction irrespective of the adaptors' interocular correlation for any adaptation duration tested. This suggests that coherent changing disparity does not contribute to motion-in-depth adaptation. Because the aftereffect duration did not saturate in the tested range of adaptation duration, it is unlikely that the lack of the effect of changing disparity was due to a ceiling effect. In Experiment 2, we used a novel adaptor that contained a unidirectional coherent interocular velocity difference signal and a bidirectional changing disparity signal that should not induce a motion aftereffect in depth. Following the adaptation, motion aftereffect in depth occurred in the opposite direction to the adaptor's motion-in-depth based on interocular velocity difference. Experiment 3 demonstrated that these results generalized in 12 untrained subjects. These experiments suggest that the contribution of interocular velocity difference to the perception of motion-in-depth is substantial, while that of changing disparity is very limited (if any), at least at the stages of direction-selective mechanisms subject to an aftereffect phenomenon.
至少有两种可能的双眼深度运动线索，即随时间变化的视差和双眼速度差异。关于它们对深度运动感知的相对贡献一直存在重大争议。在本研究中，我们使用选择性适应技术来解决这个问题。在实验1中，我们发现，对由时间相关随机点立体图描绘的深度运动进行适应，这些立体图包含连贯的双眼速度差异，无论适应持续时间如何，在任何测试的适应持续时间下，适应器的双眼相关性如何，都会在深度方向上产生运动后效。这表明连贯变化的视差对深度运动适应没有贡献。因为在测试的适应持续时间范围内后效持续时间没有达到饱和，所以不太可能是由于天花板效应导致视差变化缺乏效果。在实验2中，我们使用了一种新型适应器，它包含一个单向连贯的双眼速度差异信号和一个双向变化的视差信号，该视差信号不应在深度上诱导运动后效。适应后，基于双眼速度差异，深度方向上的运动后效出现在与适应器深度运动相反的方向。实验3表明，这些结果在12名未受过训练的受试者中得到了推广。这些实验表明，至少在受后效现象影响的方向选择性机制阶段，双眼速度差异对深度运动感知的贡献很大，而视差变化的贡献非常有限（如果有任何贡献的话）。
