Doorways Cause Forgetting
What did I come here for?
Posted May 25, 2012
Why am I here? I don’t mean this in the deep existential sense of why am I alive. I am simply wondering why I came into this room. What am I looking for? There must be a reason I left that other room and came into this one. But I can’t remember why I am here.
I’m sure we’ve all experienced this problem. We’ve been doing something in one room, realized we needed some object from another room, and walked over there to retrieve it. Simple. Of course, we arrive in that other room and have no idea of why we are there or what object we sent ourselves to retrieve. When this happens, I desperately look around for something to inspire my memory, to remind me of why I’m there.
Perhaps you’ve blamed this on your impending cognitive doom, your eventual age-related decline. Maybe you’ve worried that this may be an early sign of Alzheimer’s Disease.
I have some good news for you. It isn’t you and it isn’t evidence of age-related declines. It’s the doorway. Walking through doorways empties your mind. Doorways really cause forgetting.
In several clever studies, Gabriel Radvansky and his colleagues have investigated memory as people move through complex environments. They first conducted their research as people navigated through virtual environments playing a simple computer game. In the game, people picked up objects from one table and carried the objects until they reached another table. At the new table, they put down the old object, picked up a new object, and carried it to the next table. Every now and then, Radvansky and Copeland (2006) asked people about the object they were carrying and the one they had just put down.
The experimental manipulation is the simple and way cool part of the research. To get to the next table, sometimes people had to walk to the far end of a large room and other times they moved into a new virtual room, through a doorway. The distance traveled was the same. The time it took to make the passage was the same. And you couldn’t see the other table and object no matter what (you also couldn’t see the object you were carrying – I guess it was in your virtual pocket).
The doorway was the difference. When people walked through a doorway, they had more difficulty remembering what object they had just put down and what object they were carrying. Walking through the doorways caused forgetting.
In further research, Radvansky, Krawietz, and Tamplin (2011) demonstrated the doorway forgetting effect in a real, as opposed to a virtual, walking environment. They also studied whether returning to the original room re-instated memory. The answer: Not really. Going back to your bedroom doesn’t necessarily lead you to suddenly remember why you had journeyed to the kitchen.
So the good news is that it is perfectly normal to forget why you came here. The explanation of the doorway forgetting effect is fun to consider as well. No, I don’t think it is something about the doorway disrupting brain function. You do not need to invest in a special anti-doorway-forgetting hat.
Instead Radvansky and his colleagues have argued that we construct situational models of our surrounding environments. These models are generally vague because we can sample information from the environment any time we need more details. When we enter a new environment, we construct a new situational model, which erases the old model. Situational models would include not only vague information about the environment, but also some information about the self in that environment – like what you were carrying and doing. Thus entering a new room erases the old information – that is, doorways cause forgetting.
I think this is another example of what Dan Simons and Chris Chabris call the illusions of awareness. We believe we are more aware of our surroundings than we actually are. We actually keep only a limited model active in our awareness because we can always check back with the actual world if we need more details – why expend the cognitive resources recreating the world in our heads, when the world is constantly available to our perceptual systems. But if the environment changes or if we move to a new environment, we may lose information that we really only vaguely had in our heads and fail to notice changes in the environment (see Failing to Notice Haircuts, Missing Buildings, and Changed Conversation Partners).
Walking through a doorway replaces one vague situational model with a new one. Returning to the original room may not help because now you have simply created another new and vague situational understanding.
I regularly find myself walking into a room and wondering why I’m there. I return to where I was before and still have no idea why I left in the first place. I wander through the halls of my academic building wondering why I am here, or there, or wherever it is I find myself. Thankfully, it isn’t just because I am an absent-minded professor.