Harwerth R S, Smith E L, Crawford M L
College of Optometry, University of Houston, TX 77204-6052, USA.
Eye (Lond). 1996;10 ( Pt 2):209-16. doi: 10.1038/eye.1996.48.
Motor and sensory fusion, the basic processes of binocularity, must be present for bifoveal fixation with true fusion and stereopsis during ordinary viewing. The characteristics of motor and sensory fusion have been established for patients with normal and subnormal binocular vision; the present report describes our psychophysical studies of these processes in the macaque monkey. Three recent investigations of motor and sensory fusion in monkeys are described. The studies involved: (1) the comparability of motor and sensory fusion in monkeys and humans with normal binocular vision, (2) the effects of an early period of abnormal binocular vision on motor and sensory fusion in monkeys, and (3) the contrast sensitivity for binocular disparity in monkeys with stereo-deficiencies. The results of these studies demonstrated an excellent homology between the normal binocular vision of monkeys and humans. We also found that a period of esotropia during infancy caused deficiencies in sensory fusion, but not motor fusion. In some monkeys, the sensory deficiency persisted over the entire range of binocular disparities that were compatible with stereopsis, while other subjects demonstrated normal stereo-sensitivity for the largest fusible binocular disparities. The stereo-deficiencies of these monkeys, along with other visual attributes, suggest that their binocular vision is a viable model for the binocularity of patients with subnormal binocular vision or the monofixation syndrome.
运动融合和感觉融合是双眼视觉的基本过程，在正常注视过程中，为实现真正融合和立体视觉的双凹注视，这两种融合过程必须存在。运动融合和感觉融合的特征已在双眼视力正常和低于正常水平的患者中得到确定；本报告描述了我们对猕猴这两种过程的心理物理学研究。本文描述了最近对猕猴运动融合和感觉融合的三项研究。这些研究包括：（1）具有正常双眼视力的猕猴和人类在运动融合和感觉融合方面的可比性，（2）早期异常双眼视觉对猕猴运动融合和感觉融合的影响，以及（3）存在立体视觉缺陷的猕猴对双眼视差的对比敏感度。这些研究结果表明，猕猴和人类的正常双眼视觉之间存在极好的同源性。我们还发现，婴儿期的内斜视会导致感觉融合缺陷，但不会导致运动融合缺陷。在一些猕猴中，感觉缺陷在与立体视觉相容的整个双眼视差范围内持续存在，而其他受试猕猴在最大可融合双眼视差时表现出正常的立体视觉敏感度。这些猕猴的立体视觉缺陷以及其他视觉属性表明，它们的双眼视觉是双眼视力低于正常水平的患者或单眼注视综合征患者双眼视觉的一个可行模型。
