Dickinson J Edwin, Almeida Renita A, Bell Jason, Badcock David R
School of Psychology, University of Western Australia, Crawley, Perth, WA, Australia.
J Vis. 2010 Nov 1;10(13):5. doi: 10.1167/10.13.5.
Adaptation to prevailing stimuli is a ubiquitous property of the visual system that optimizes its dynamic range. The perceived difference in orientation of successively presented lines of similar orientation is exaggerated and the perceived shape of an object is influenced by previously experienced shapes. Change in perceived shape is assumed to arise through the adaptation of shape detectors. Here we consider an alternative: adaptation within a substrate of local oriented line detectors resulting in enhanced shape contrast in similar shapes. We show that the perceived shapes of a spatially coincident circle and Cartesian grid can be manipulated independently by adaptation to geometrically transformed copies of themselves. The same transformation was applied to the circle and the grid to create the adaptors; therefore, the specificity of the effects of adaptation demonstrates that the visual system adapts to the shape of objects rather than applying transformations to the reference frame of the visual field. The tilt aftereffect predicts local changes in perceived orientation, and fields of such local effects can often account for the global change in perceived shape of complex objects, including faces.
适应当前刺激是视觉系统的一个普遍特性，它优化了视觉系统的动态范围。相继呈现的相似方向线条的方向感知差异会被放大，并且物体的感知形状会受到先前经历形状的影响。感知形状的变化被认为是通过形状探测器的适应而产生的。在这里，我们考虑另一种情况：在局部定向线条探测器的基质内进行适应，从而在相似形状中增强形状对比度。我们表明，通过适应空间重合的圆形和笛卡尔网格的几何变换副本，可以独立地操纵它们的感知形状。对圆形和网格应用相同的变换来创建适应器；因此，适应效果的特异性表明视觉系统适应物体的形状，而不是对视野的参考框架应用变换。倾斜后效预测感知方向的局部变化，并且这种局部效应的区域通常可以解释复杂物体（包括面部）感知形状的全局变化。
