Malo Jesús, Gutiérrez Juan
Dept. d'Optica, Facultat de Física, Universitat de València, Spain.
Network. 2006 Mar;17(1):85-102. doi: 10.1080/09548980500439602.
It has been argued that the aim of non-linearities in different visual and auditory mechanisms may be to remove the relations between the coefficients of the signal after global linear ICA-like stages. Specifically, in Schwartz and Simoncelli (2001), it was shown that masking effects are reproduced by fitting the parameters of a particular non-linearity in order to remove the dependencies between the energy of wavelet coefficients. In this work, we present a different result that supports the same efficient encoding hypothesis. However, this result is more general because, instead of assuming any specific functional form for the non-linearity, we show that by using an unconstrained approach, masking-like behavior emerges directly from natural images. This result is an additional indication that Barlow's efficient encoding hypothesis may explain not only the shape of receptive fields of V1 sensors but also their non-linear behavior.
有人认为，在类似全局线性独立成分分析（ICA）的阶段之后，不同视觉和听觉机制中的非线性的目的可能是消除信号系数之间的关系。具体而言，在施瓦茨和西蒙切利（2001年）的研究中表明，通过拟合特定非线性的参数以消除小波系数能量之间的依赖性，能够再现掩蔽效应。在这项工作中，我们给出了一个不同的结果，它支持相同的高效编码假设。然而，这个结果更具普遍性，因为我们不是假设非线性具有任何特定的函数形式，而是表明通过使用一种无约束的方法，类似掩蔽的行为直接从自然图像中出现。这一结果进一步表明，巴洛的高效编码假设不仅可以解释V1传感器感受野的形状，还可以解释它们的非线性行为。
