You’ve just walked into a room with a clear purpose in mind. Except now you can’t remember what it was you set out to do. Is it just your imagination, or does walking into a different room make you forget?
We all forget things. And most of us have had the experience of walking into a room and feeling confused. Maybe you’ve just gone into the kitchen to find your keys, but by the time you got there, you’d forgotten it was the keys you were after.
To explore why this happens, researchers have carried out a number of different experiments. First, they got people playing a video game. In the game, players used arrow keys to move around the virtual space. Their task was to pick up a coloured object from a table, move to another table, put the object down and pick up another one. Sounds pretty simple. But once they had picked it up, the players could no longer see what it was they were carrying.
The researchers asked the players at various times what colour and shape the object they were carrying was. And it turned out that if the player had just moved through a doorway in the game, they were much worse at remembering. Worse than if they had moved the same distance within the same room.
The next step was to recreate this game in real life. People in the study walked around in the real world, picking up and putting down objects on real tables. They carried the objects in shoeboxes so they couldn’t see them.
Sure enough, even when people walked exactly the same distance, their memory of what was in the box was much worse if they had walked through a doorway. People were two or three times more likely to forget after walking through a door.
Location, location, location
You might think all these players needed to do was go back to the room they were originally in. We call this the encoding specificity principle. The idea is you’ll remember something better in the same context as you first took in the information. This is why we’re told the best place to study for an exam is the same place you’ll be taking the exam.
But the researchers tested this too. And in the experiment, going back to the original room where they picked up the object didn’t help people to remember what it was they were carrying.
What’s clear from this research is that location matters. It’s been called the Location Updating Effect. When we find ourselves in a new location, we have trouble remembering information from previous locations. Even if we were in the previous place only moments earlier.
Out with the old, in with the new
After lots of research, this experience is now also known as the Doorway Effect. And it explains some interesting things about how our memories work.
We know our memories are divided up into separate episodes or events. At any one moment, you have all the information you need to do during this particular event. But it’s not possible to have everything in your brain constantly at hand. Breaking our thoughts and memories up into separate sections is a good way to organise them.
Once a particular event is over, our brains discard some of the old information, ready for new, more relevant things. How do we decide when an event is over? This research suggests one of the triggers for our brains to decide a new event has begun is walking through a doorway. Researchers call it an event boundary.
When you pass through a doorway, it signals to your brain that something new has begun. Information that was relevant in the previous room probably isn’t as relevant or important now. Out with the old, to make room for the new.
Amazingly, even just imagining walking through a door was enough to make people forget things more easily.
And if you’re thinking all this is just a cover for us becoming more forgetful as we age, think again. The effects were the same for people in their late teens and early twenties as for people in their sixties and seventies.
What can we do about the Doorway Effect? Not much, unless you want to follow the advice of one of the lead authors of this research:
Doorways are bad. Avoid them at all costs. – Professor Gabriel Radvansky