Prosopagnosia is a medical condition that stops people from recognizing faces. But how common is it and why does it happen?
It was Jacob Hodes' first day at college. He can still recall spending an enjoyable afternoon being shown around campus by a second-year student named Daniel Byrne, who happened to be from his hometown. Jacob then spent the rest of the year ignoring him. “I never saw him again,” he says. “Well, I'm sure I walked past him plenty of times, but I just didn't see him.” This behavior wasn't intentional. Jacob just couldn't recollect what his fellow student looked like. He had had the same trouble all his life. Friends and relatives would greet him, and he would have no idea who they were. It wasn't until five years ago that it all made sense.