We've all seen the black and white optical illusions in middle school about whether or not the picture is a face or vase, or the old woman or young woman, but we're all grown adults and we like to see cooler stuff than that. The ones that if we were on LSD or tripping on shrooms that would
The viewer (test person) sees a picture representing a Venetian mask and is asked if he/she notices something special in it. A surprising number don’t notice that the main features of the mask are actually composed of two distinct faces: a man and a woman kissing one another.
Compare the upside-down face on the left of the lower figure with the upright face on the right. The upside-down version looks much thinner, – altogether a longer shaped face than the upright version. Of course the pictures are identical. This illusion illustrates the internal features of the face, (eyes, nose, mouth) can distort our perception of face shape.