How Many Memories Fit In Your Brain?

If you were to walk into an unfamiliar room, look around briefly and then close your eyes, how much could you could remember of what you saw? I’ll give you a chance to find out how your visual memory compares with other people’s, but be warned: your memory is probably worse than you imagine.
Consider an experiment that was done by Daniel Simons, a psychologist at the University of Illinois. He or a member of his lab would walk up to a pedestrian on the street and ask him or her for directions. While the pedestrian was responding, workmen carrying something large (like a door frame) would walk between them. As the workmen passed, the experimenter switched places with someone else. Only half of the pedestrians noticed, even though the two people could be quite different.
We can’t quite replicate that experiment online, but there’s another test for short-term visual memory you can take here. It lasts about five minutes and is part of an experiment at the Visual Cognition Laboratory at Harvard University, an online project founded by Joshua Hartshorne, a graduate student in psychology.