Stoner G R, Albright T D
Vision Center Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037.
Nature. 1992 Jul 30;358(6385):412-4. doi: 10.1038/358412a0.
The motions of overlapping contours in a visual scene may arise from the physical motion(s) of either a single or multiple surface(s). A central problem facing the visual motion system is that of assigning the most likely interpretation. The rules underlying this perceptual decision can be explored using a visual stimulus formed by superimposing two moving gratings. The resultant percept is either that of a single coherently moving 'plaid pattern' (coherent motion) or of the two component gratings sliding noncoherently across one another (noncoherent motion). When plaid patterns are configured to mimic one transparent grating overlying another, the percept of noncoherent motion dominates. We now report that neurons in the visual cortex of rhesus monkeys exhibit changes in direction tuning that parallel this perceptual phenomenon: sensitivity to the motions of the component gratings is enhanced under conditions that favour the perception of noncoherent motion. These results challenge models of cortical visual processing that fail to take into account the contribution of figural image segmentation cues to the analysis of visual motion.
视觉场景中重叠轮廓的运动可能源于单个或多个表面的物理运动。视觉运动系统面临的一个核心问题是赋予最可能的解释。可以使用叠加两个移动光栅形成的视觉刺激来探索这种感知决策背后的规则。最终的感知要么是单个连贯移动的“格子图案”（连贯运动），要么是两个组成光栅彼此非连贯地滑动（非连贯运动）。当格子图案被配置为模仿一个透明光栅覆盖在另一个之上时，非连贯运动的感知占主导。我们现在报告，恒河猴视觉皮层中的神经元表现出与这种感知现象平行的方向调谐变化：在有利于非连贯运动感知的条件下，对组成光栅运动的敏感性增强。这些结果挑战了那些没有考虑图形图像分割线索对视觉运动分析贡献的皮层视觉处理模型。
