MONDAY, Nov. 21 (HealthDay News) -- Ever go into another room for something and then forget what you were there for? A new study suggests that simply passing through a doorway can cause you to forget why you came into a room or what you wanted to find.

"Entering or exiting through a doorway serves as an 'event boundary' in the mind, which separates episodes of activity and files them away," Gabriel Radvansky, a psychology professor at the University of Notre Dame, said in a university news release.

"Recalling the decision or activity that was made in a different room is difficult because it has been compartmentalized," he explained.

The study included three experiments in which college students performed memory tasks while crossing a room and after passing through a doorway.

The first experiment used virtual reality. Participants first moved through a doorway from one room to another, selected an object on a table and exchanged it for an object on a different table. They then did the same object exchange without first crossing through a doorway.

The participants were more likely to experience forgetfulness after passing through a doorway compared to moving the same distance across a room. This suggests that the "event boundary" of the doorway impairs the ability to remember thoughts or decisions made in a different room, according to Radvansky.

The second experiment was conducted in a real-world setting and confirmed that walking through a doorway caused the participants to experience memory lapses.

The third experiment, which used several doorways that led back to the room in which the participants started, demonstrated that the act of passing through a doorway did seem to actually act as an event boundary that affected memory.

The study was published in the Quarterly Journal of Experimental Psychology.

More information

The U.S. National Institutes of Health has more about forgetfulness.