There was a reason I came in this room. There must have been. Keys, was it? No, those are in my hand. Why … did I come in here? This scene plays out with alarming regularity in my apartment, and it apparently has a name: It’s called the “doorway effect,” writes cognitive scientist Tom Stafford for the BBC. Stafford explains that understanding this annoying everyday memory blip can help you understand more about the way human memory works.