Zhang J, Yeh S L, De Valois K K
Neurobiology Group, University of California, Berkeley 94720.
Vision Res. 1993 Dec;33(18):2721-32. doi: 10.1016/0042-6989(93)90231-k.
When a moving aperture contains a drifting grating, the perception of aperture movement is strongly affected by the grating movement. We have studied this interaction, using a moving circular patch of sinusoidal grating matched to the background in mean luminance. The circular window, or aperture, could be defined either by an abrupt transition from a full-contrast grating to the background (hard aperture) or by a two-dimensional Gaussian fall-off in contrast (soft aperture). The grating movement could be controlled independently of the aperture motion. Subjects judged the direction of the aperture movement (i.e. the movement of the patch as a whole). We find that an illusory motion of a stationary aperture can be induced depending on the direction of the grating drift. A hard aperture presented in the fovea appears to move in the direction opposite the grating movement, demonstrating simultaneous motion contrast. However, a soft aperture presented in the periphery appears to move in the same direction as the drifting grating, demonstrating motion integration (assimilation). These results are discussed in the context of interactions between short-range and long-range motion mechanisms and with respect to the significance of boundaries in determining the figure-ground relationship of motion signals.
当一个移动的孔径包含一个漂移光栅时，孔径运动的感知会受到光栅运动的强烈影响。我们使用一个与背景平均亮度相匹配的正弦光栅的移动圆形区域来研究这种相互作用。圆形窗口或孔径可以通过从全对比度光栅到背景的突然转变（硬孔径）或通过对比度的二维高斯衰减（软孔径）来定义。光栅运动可以独立于孔径运动进行控制。受试者判断孔径运动的方向（即整个区域的运动）。我们发现，根据光栅漂移的方向，可以诱导静止孔径的虚幻运动。中央凹呈现的硬孔径似乎朝着与光栅运动相反的方向移动，显示出同时运动对比度。然而，外周呈现的软孔径似乎朝着与漂移光栅相同的方向移动，显示出运动整合（同化）。将在短程和长程运动机制之间的相互作用以及边界在确定运动信号的图形-背景关系方面的重要性的背景下讨论这些结果。
