Read Jenny C A, Cumming Bruce G
Institute of Neuroscience, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, UK.
Nat Neurosci. 2007 Oct;10(10):1322-8. doi: 10.1038/nn1951. Epub 2007 Sep 9.
One of the fundamental challenges of binocular vision is that objects project to different positions on the two retinas (binocular disparity). Neurons in visual cortex show two distinct types of tuning to disparity, position and phase disparity, which are the results of differences in receptive field location and profile, respectively. Here, we point out that phase disparity does not occur in natural images. Why, then, should the brain encode it? We propose that phase-disparity detectors help to work out which feature in the left eye corresponds to a given feature in the right. This correspondence problem is plagued by false matches: regions of the image that look similar, but do not correspond to the same object. We show that phase-disparity neurons tend to be more strongly activated by false matches. Thus, they may act as 'lie detectors', enabling the true correspondence to be deduced by a process of elimination.
双眼视觉的一个基本挑战在于，物体在两个视网膜上的投影位置不同（双眼视差）。视觉皮层中的神经元对视差、位置视差和相位视差表现出两种不同类型的调谐，它们分别是感受野位置和轮廓差异的结果。在这里，我们指出相位视差在自然图像中不会出现。那么，大脑为什么要对其进行编码呢？我们提出，相位视差检测器有助于确定左眼的哪个特征与右眼的给定特征相对应。这个对应问题受到错误匹配的困扰：图像中看起来相似但并非对应于同一物体的区域。我们表明，错误匹配往往会更强烈地激活相位视差神经元。因此，它们可能充当“测谎仪”，通过排除过程推断出真正的对应关系。
