You cross a door and your head closes the scene

You get up to fetch your glasses, cross the living room door and three steps later you no longer know what you were going for. Relax, it is not your age. The culprit is shaped like a door frame.

Gabriel Radvansky, a psychologist at the University of Notre Dame, measured it in 2011 with Sabine Krawietz and Andrea Tamplin. Volunteers carried an object hidden inside a box from one table to another. Some covered the distance within a single room; others walked through a doorway. The ones who walked through remembered worse what they were holding. They ran it in real rooms and in virtual rooms, and it came out the same.

The detail that explains it came afterwards: going back to the room you started in did not undo the forgetting. If it were a matter of scenery, going back would give it to you. What your head does is close the episode at the threshold and open a new one, the way you save a file and open the next. The previous one is still on the disk, but it is no longer on the screen.

Naming works against it. Before you cross, say out loud what you are going to fetch — «my glasses», two words — and carry it spoken to the other side.