Fig. 8.

The NBCM receptive fields depend on the statistical structure of underlying images; they are not artifacts produced by quirks of the pixel grid. (A) Receptive fields produced from circularly-windowed images are qualitatively similar to those from square images (Fig. 3B and C). (B and C) When the images are rotated by 22.5 (B) or 45° (C), the receptive fields rotate accordingly. (D–F) Fourier-space plots showing the half-maximum contours for the NBCM receptive fields shown in A–C. The effect of rotation (E and F) is particularly clear in this representation, matching the rotation of the images (oblique axes).