Syrkin G, Yinon U, Gur M
Maurice and Gabriela Goldschleger Eye Research Institute, Tel Aviv University Sackler Faculty of Medicine, Chaim Sheba Medical Center, Tel Hashomer, Israel.
Exp Brain Res. 1994;102(2):319-26. doi: 10.1007/BF00227518.
Mach bands are a visual illusion evoked by a luminance ramp dividing two luminance plateaux (blurred edges), but not by sharp edges. Recently, two physiology-based models have tried to cope with the psychophysical data concerning this phenomenon. The basic components of both models are neurons with even- or odd-symmetric receptive fields (RFs). Both models predict that odd-symmetric cells respond better to sharp edges, while even-symmetric cells respond better to blurred ones. We have measured the responses of 34 primary visual cortex simple cells of the cat to blurred edges of various degrees. Twenty-one cells had RFs of even symmetry, responding best to blurred edges than to sharp ones. The rest were odd-symmetric cells, of which 12 responded best to sharp edges, and only one exceptional cell responded best to a 0.85 degrees-wide edge. Thus, the different cell types responded as predicted by the two different Mach band models. Simple cells may thus serve as the physiological basis of the psychophysical phenomenon of Mach bands. Furthermore, our evidence suggests the existence of inhibition between odd- and even-symmetric cells, as predicted by one of the models.
马赫带是一种视觉错觉，由将两个亮度平台（模糊边缘）分隔开的亮度斜坡引发，而不是由锐利边缘引发。最近，两种基于生理学的模型试图处理与该现象相关的心理物理学数据。这两种模型的基本组成部分都是具有偶对称或奇对称感受野（RFs）的神经元。两种模型都预测，奇对称细胞对锐利边缘反应更好，而偶对称细胞对模糊边缘反应更好。我们测量了猫的34个初级视觉皮层简单细胞对不同程度模糊边缘的反应。21个细胞具有偶对称的感受野，对模糊边缘的反应比对锐利边缘的反应更好。其余的是奇对称细胞，其中12个对锐利边缘反应最佳，只有一个特殊细胞对0.85度宽的边缘反应最佳。因此，不同类型的细胞的反应正如两种不同的马赫带模型所预测的那样。简单细胞因此可能是马赫带心理物理学现象的生理学基础。此外，我们的证据表明，正如其中一个模型所预测的那样，奇对称和偶对称细胞之间存在抑制作用。
