Webster M A, De Valois R L
J Opt Soc Am A. 1985 Jul;2(7):1124-32. doi: 10.1364/josaa.2.001124.
If striate cells had the receptive-field (RF) shapes classically attributed to them, their preferred spatial frequencies would vary considerably with orientation. Other models of RF shape would predict a greater independence between orientation and spatial-frequency tuning. We have examined this by recording the responses of cat striate-cortex cells to a wide range of different spatial-frequency and orientation combinations. In almost all cells studied, peak orientation did not consistently vary with spatial frequency, but the majority of cells showed some change in peak spatial-frequency tuning with orientation. The amount of change in peak spatial frequency tended to be greater for cells that were narrowly tuned for orientation. However, cells narrowly (and also very broadly) tuned for spatial frequency tended to show considerable independence of spatial-frequency and orientation tuning, and in all but a few cells the degree of change was less than predicted by the classic RF model. Such cells were found to fire only to patterns whose local spatial spectra fell within a compact, restricted, roughly circular two-dimensional spatial-frequency region. We conclude that the two-dimensional RF shape of striate cells more closely approximates that predicted by a two-dimensional Gabor model or by a Gaussian-derivative model than it does the classic shape based on the output of geniculate cells with aligned RF's.
如果纹状细胞具有传统上赋予它们的感受野（RF）形状，那么它们偏好的空间频率会随方向而有很大变化。其他RF形状模型则预测方向和空间频率调谐之间具有更大的独立性。我们通过记录猫纹状皮层细胞对各种不同空间频率和方向组合的反应来对此进行了研究。在几乎所有研究的细胞中，峰值方向并不随空间频率持续变化，但大多数细胞的峰值空间频率调谐会随方向有一些变化。对于方向调谐较窄的细胞，峰值空间频率的变化量往往更大。然而，空间频率调谐较窄（以及非常宽）的细胞往往表现出空间频率和方向调谐的相当大的独立性，并且除了少数细胞外，变化程度小于经典RF模型的预测。发现这类细胞仅对其局部空间频谱落在一个紧凑、受限、大致圆形的二维空间频率区域内的图案放电。我们得出结论，纹状细胞的二维RF形状更接近二维Gabor模型或高斯导数模型所预测的形状，而不是基于具有对齐RF的膝状细胞输出的经典形状。
