E-mailed Illusions

Here are some images that someone sent to me. They are all pretty old and have been around awhile, but still, they are rather fun. Some of them also are duplicates of ones  found on other sites. These are thumbnails, which means that clicking on each picture will enlarge it for better viewing.

This is, I believe, based on (or maybe is) a painting by Maurice Escher. If anyone knows the actual artist or citation, please send it to me.

This is an illusion known as the Hermann Grid. It's a fun example of the result of center-surround antagonism in receptive fields (if you know what that is).

Another illusion due to contrast and receptive field effects.

This is another example of an "impossible figure"--the type of figure that Escher was so fond of drawing.

This illusion is the result of fatiguing receptors.

This one is a perceptual illusion that arises from our brains' attempts to resolve figure-ground relationships.

This is an ambiguous figure.

This is a variation of the famous "Stroop Effect;" however, I think it's important to point out that neither Stroop nor any other reputable investigator uses the terms "right brain" or "left brain." There really is no such dichotomy since we all are "whole brained" for the most part (except in rare surgical or physiopathological situations).

This is based on a painting (Degas I think) entitled "All Is Vanity." Rather depressing if you ask me, but another example of figure-ground relationships and ambiguity.

I'm not sure if this one is politically incorrect. I didn't create it, thus I didn't write the caption that accompanies it.

This pastoral scene also contains the silhouette of a baby--can you see it sucking it's little thumb?