Images related to Livingston's Lecture

The first image I found is a rather popular optical illusion. This illusion is much like Livingston's example of the homogenous gray disc that appears to be shaded from light to dark because of the shaded background. According to Livingston, the center-surround cells can't tell the difference between "increasing light to the center or decreasing light to the surround." This manipulation of luminence creates the perception that A and B (labeled in the optical illusion) are two different shades of gray. I chose this particular example because unlike Livingston's example, where the shades seemingly barely differ, this illusion makes it seem like the two shades of gray are on the far sides of the spectrum. Block A looks much, much darker than block B. However, because of the manipulation of luminence, (and I verified this on MS paint) A and B are in fact the same shade.
The second image I found is related to the mosaic images that Livingston refers to. Much like the Babe Ruth mosaic image, this image illustrates how central vision and peripheral vision differ. The central vision sees the small, individual images of Simpson's characters, whereas the peripheral vision sees the overall image of Homer Simpson. These contrasting perceptions create a dual effect.