He Z J, Nakayama K
Department of Psychology, Harvard University, Cambridge, MA 02138.
Vision Res. 1994 Aug;34(16):2125-35. doi: 10.1016/0042-6989(94)90322-0.
Previous psychophysical studies have revealed that shape similarity can affect apparent motion correspondence. Such results however, do not specify the level of representation, at which shape similarity is defined. We sought to understand this question by using a 2 x 2 competitive apparent motion paradigm. We manipulated the binocular disparity of the motion stimuli (tokens) relative to adjacent squares to selectively change the internal surface representation of the tokens while keeping early filtered representation intact. When two sets of differently oriented tokens (45 degrees,-45 degrees bars) were used, there was a preference for seeing motion between tokens having the same orientation. However, such a motion bias was reduced when tokens became part of a large surface square seen either as amodally occluded in the background or as a transparent surface modally completed in front. Since shape differences at the early filtering level remain essentially intact (i.e. + 45 degrees vs -45 degrees) our findings support the surface level hypothesis. Perceived surface shape rather than shape defined by early filters largely determines motion correspondence.
以往的心理物理学研究表明，形状相似性会影响表观运动对应性。然而，这些结果并未明确形状相似性是在何种表征水平上被定义的。我们试图通过使用2×2竞争性表观运动范式来理解这个问题。我们操纵运动刺激（图形）相对于相邻方块的双眼视差，以选择性地改变图形的内表面表征，同时保持早期滤波表征不变。当使用两组不同方向的图形（45度、-45度的线条）时，人们更倾向于看到相同方向图形之间的运动。然而，当图形成为在背景中被非模态遮挡或在前面被模态完成的透明表面的大表面方块的一部分时，这种运动偏好就会减弱。由于早期滤波水平上的形状差异基本保持不变（即+45度与-45度），我们的研究结果支持表面水平假说。感知到的表面形状而非早期滤波器定义的形状在很大程度上决定了运动对应性。
