Oops! Just when you’ve stepped out the door in the morning, you realise your sunglasses are still on the kitchen counter. No problem. It’ll be quick to get them. You unlock the door, walk down the hall, enter the kitchen, and… wait, what was it you needed?
The purpose of your errand evaporates from your mind in just a minute or two. You call yourself crazy, or shake your head and say you’re getting old, but in fact it’s neither of those things. You just experienced the Doorway Effect, and it doesn’t mean your brain is doomed.
In a 2011 study, 55 college students played a computer game in which they explored a virtual building, collecting and carrying objects as they went from room to room. A picture of an object periodically popped up on the screen as the participants played – sometimes just after they entered a room, other times while in the middle of a room. If the object shown was what they were currently carrying or had just put down, they selected “Yes.”
The researchers ran the experiment again to confirm their results, this time creating a real-world version of the environment. The objects were hidden in boxes when carried by participants so they couldn’t double-check.
Both trials noted the same phenomenon: the simple act of walking through a doorway made participants forget what they were doing. Within a room, memories remained mostly intact. Crossing a threshold, however, hit some kind of mental delete button. The researchers concluded that the brain perceives doorways as a cut-off point – with one context and set of associated memories on one side, and a different context and set of associated memories on the other.
Our memories are “embedded in webs of associations,” explains the BBC. “That can be the physical environment in which we form them, which is why revisiting our childhood home can bring back a flood of previously forgotten memories, or it can be the mental environment – the set of things we were just thinking about when that thing popped into mind.”
The Doorway Effect occurs when you change both your physical and your mental environment. With both contexts changed, the sunglasses on the kitchen counter woosh straight out of your brain.
Fortunately, science has also given us a solution for improving memory: drink more champagne.