Figure 1.

A simulation of the perceptual information carried by ON- and OFF-centre pathways. (a) Two example images: a white-on-black eye-chart and a frame of a natural scene movie of a child scooting. Both subtend 24° of visual angle. (b) These two images were convolved by a bank of difference of Gaussian filters followed by rectification to provide a rough approximation of the information carried by ON-centre pathways. (c) Images filtered by an inverted version of the same bank of Gaussian filters followed by rectification provide a rough approximation of the information carried by OFF-centre pathways. (d) The difference of the images (b,c) restore a band-pass version of the original image. (e) The sum of the images (b,c) represents an approximation of one potential perceptual outcome of simultaneously stimulating both ON-centre and OFF-centre pathways. Movie versions are shown for (a–e) in the electronic supplementary material.