Orientation- and frequency-modulated textures at low depths of modulation are processed by off-orientation and off-frequency texture mechanisms
Orientation- and frequency-modulated textures at low depths of modulation are processed by off-orientation and off-frequency texture mechanisms
复制标题
低调制深度的方向和频率调制纹理由偏离方向和偏离频率纹理机制处理
DOI：
10.1016/s0042-6989(01)00315-7
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发表时间：
2002
期刊：
影响因子：
1.8
通讯作者：
F. Kingdom
中科院分区：
文献类型：
--
作者：
N. Prins;F. Kingdom
直观地看，方向调制(OM)和频率调制(FM)纹理似乎是利用对包含在纹理中的一阶(亮度)信息最敏感的一阶通道来处理的。这一假设意味着OM或FM纹理的检测或分割是通过二阶机制来完成的，该机制从调谐到纹理的中心或方向和空间频率分布的峰值的神经元接收它们的一阶输入。在这里，我们展示了在调制深度较低时，情况并非如此。使用自适应范式，我们证明了OM和FM纹理感知所涉及的一阶过滤器是那些最大化不同纹理区域之间的差异响应的过滤器。我们对这一结果的解释类似于Regan和Beverley[J.Opt.SoC。上午好。73(1983)1684；J.Opt.SoC。上午好。A 2(1985)147]用于简单的光栅刺激。然而，我们表明，虽然Regan和Beverley的结果可以根据所涉及的假定机制的调谐函数来解释，但我们的结果可以根据织构本身的特征来解释。讨论了我们的发现的一些启示。
Intuitively it may seem likely that orientation-modulated (OM) and frequency-modulated (FM) textures are processed utilizing the first-order channels that are most responsive to the first-order (luminance) information contained in the textures. This assumption would imply that the detection or segmentation of OM or FM textures is accomplished by second-order mechanisms that receive their first-order input from neurons tuned to either the center, or to the peaks in the orientation and spatial-frequency distribution of the texture. Here we show that at low depths of modulation this is not the case. Using an adaptation paradigm, we show that the first-order filters involved in the perception of OM and FM textures are those which maximize the differential response between the different texture regions. Our explanation of this result is similar to that made by Regan and Beverley [J. Opt. Soc. Am. 73 (1983) 1684; J. Opt. Soc. Am. A 2 (1985) 147] for simple grating stimuli. However, we show that whereas Regan and Beverley's results could be accounted for on the basis of the tuning functions of the putative mechanisms involved, our results can be explained in terms of the characteristics of the textures themselves. Some implications of our finding are discussed.