Each Friday morning I post a riddle or brain teaser. The idea is to get you to think outside the box and exercise your brain. However, since I am traveling abroad with limited access to my blog, I thought I’d share an optical illusion that you may also enjoy.
The grid illusion below involve shape, position and color. The contrasts converge to produce the illusion of black dots at the intersections.
So why do we see the black dots? The receptive field of the retina light and dark receptors compete with one another to become active. Once a receptor is active it inhibits adjacent receptors and it is this inhibition that creates the contrast.
There are white dots in the grid.
UM, is there something wrong with me? I see WHITE dots at the intersections.
Gosh, how wacky! I was chasing those black dots all over – probably explains why I fail the peripheral vision test at the opticians each year!
So why do I see white dots???