van Mierlo Christa M, Brenner Eli, Smeets Jeroen B J
Research Institute Move, Faculty of Human Movement Sciences, VU University, Amsterdam, The Netherlands.
Vision Res. 2011 Jun 1;51(11):1249-53. doi: 10.1016/j.visres.2011.03.015. Epub 2011 Mar 31.
Visual tasks that involve judging distance or depth obviously benefit from considering retinal disparities and ocular convergence, but various simple visual thresholds are also lower when looking with two eyes. This is also true for stereo-blind subjects. One benefit of using two eyes is that looking with two eyes provides two chances of making the critical distinction. From the literature it would appear that using two eyes might only be an advantage for low contrast stimuli and simple tasks. We here demonstrate that stereo-blind subjects can benefit from using two eyes when making judgments about clearly visible complex stimuli. The task was to judge the direction of rotation of a simulated transparent cylinder. Stereo-blind subjects performed better when looking with two eyes than when looking with their preferred eye. It did not matter for their performance whether the images in their two eyes were correlated or not. Various control experiments ascertained that they judged the direction of rotation from the images in each eye separately and then combined these judgments, rather than relying on differences between the images in the two eyes. These findings raise doubts about the validity of using monocular vision as a control for quantitative studies of the use of binocular disparity.
涉及判断距离或深度的视觉任务显然受益于考虑视网膜视差和眼球会聚，但用双眼观察时各种简单视觉阈值也更低。这对于没有立体视觉的受试者也是如此。使用双眼的一个好处是，用双眼观察提供了两次做出关键区分的机会。从文献来看，使用双眼可能仅对低对比度刺激和简单任务具有优势。我们在此证明，没有立体视觉的受试者在对清晰可见的复杂刺激进行判断时，使用双眼会有所受益。任务是判断一个模拟透明圆柱体的旋转方向。没有立体视觉的受试者用双眼观察时比用其优势眼观察时表现更好。他们双眼图像是否相关对其表现并无影响。各种对照实验确定，他们分别根据每只眼中的图像判断旋转方向，然后综合这些判断，而不是依赖于双眼图像之间的差异。这些发现对将单眼视觉用作双眼视差使用定量研究对照的有效性提出了质疑。
