MIT's AI figured out how humans recognize faces

The as-yet-unnamed system is a computational model of how the human brain recognizes faces, and was trained to identify particular visages from a battery of sample images it was fed. In the process of learning to spot faces, the program created an intermediate processing step that looked at "a face's degree of rotation - say 45 degrees from center - but not the direction." In layman's terms, this means the system, which was looking for invariance (or non-difference) between faces, was able to do so regardless of whether a face was flipped, as long as it was rotated in the same angle. That property is known as "mirror symmetry." This discovery excites scientists because it duplicates a previously observed feature of how primates process faces, indicating that the system might be doing something similar to the brain.