This ghostly face appears to mysteriously change its features when you look at it for a while (Some viewers have even reported experiencing traumatic visions!). But that’s not all – if you unfocus your eyes and look steadily through the image, you’ll notice that after about 10-15 seconds, the face gradually disappears…
This spooky portrait is created by merging together 50 common human faces. The process of averaging multiple exposures of human faces isn’t really new. In fact, as early as 1879, Sir Frances Galton experimented with this photographic technique, and others have since followed suit, using it for artistic or social purposes. Artists like Ken Kitano, Jason Salavon, Donald Scott Bray have all borrowed this technique for their own work.
But why does the face seem to change or disappear? The mechanism underlying this illusion is neural adaptation, as in Troxler fading, combined with the ensuing filling-in being driven by face circuits. If you want to learn more about the mechanism behind this phenomenon, read on.
I even created a gif to enhance the apparition of multiple distinct faces by animating two frames indefinitely. Even though the face of each frame is identical, the resulting human face seems to morph and move.
