Figure 1.

Wavelet decomposition of stimuli. a, Random sequences of natural scenes were presented, centered on the CRF of each neuron and covering approximately three times the CRF diameter, r. b, Each stimulus frame was decomposed using a wavelet pyramid (the BWT), containing odd- and even-symmetric wavelets, over a region covering 3r × 3r. To demonstrate the range of spatial scales of the BWT analysis, this panel presents examples of these wavelets at three spatial scales (f, 3f, 9f). c, Two complete scales of the wavelet pyramid. The wavelets cover four orientations (0, 90, 180, 270°) at three scales (f, 3f, 9f; although only the lower two scales are shown here) and tile the x–y plane.