Two-tone images give little information.
Suddenly, a face appears.
Our brains’ recognition of objects depends on their orientation. What do you see in this image?
Our brains have a spectacular ability to recognize faces. Minimal information is required to do so — for example, a nose, a mouth, and two eyes. In the first image above, there isn’t quite enough distinguishing information for most people to see a face. However, when the image is inverted (the second image above), a face appears. This results because our brain is tuned to seeing faces in this orientation.