What's the optical illusion called the Haunted Mansion busts to watch you as you walk by them?

Answer 1

Isn't that the weirdest thing! I was one of the first to ride the Haunted Mansion ride at the Disneyland in Anaheim back in the 70's. I loved how they did that!
Here is what I have learned: The busts in the library, the ones that seem to follow your eyes when you get right up next to them, they aren't busts at all. Rather, they are more like the inside of a plaster cast used for making latex masks. The inward curvature along with lighting, creates the optical illusion you experience.