Memory Portal

You find yourself in a strange house, where each door appears normal. However, when you walk through any door and into the next room, you immediately forget the reason you entered.

These memory portals are daunting! You start writing things on your skin like the guy from Memento so you don’t forget. The only way to remember anything is to go back through that same door, into the room you just came from.

Is this Twilight Zone episode a little too on the nose? I just walked into the kitchen to grab… something. I don’t remember what, exactly.

So, I headed back to my living room, where I suddenly remembered that I went into the kitchen to start a pot of water boiling for the pasta I’m about to cook. What’s going on here?

It turns out that I’m not alone—this happens to nearly everyone, and it has become a documented phenomenon. It’s most commonly called the doorway effect, though scientists will often use the term event boundary effect.

Event boundary. Now there’s an interesting combination of time and space in a phrase. That alone tells us an awful lot about the way your mind works.

Contrary to the way it seems to us, your brain isn’t a camcorder or a smartphone when it records memories. Instead, it creates little chapters based on episodes or scenes, kind of like DVDs in the 2000s.

When you walk through a door, it’s an obvious signal to your brain that you have entered a new scene. There’s an entirely different context in here—coffee and cutting happen in this room, whereas writing and sitting happen in this other room.

There’s only so much working memory to go around, and I personally feel that acutely nearly every day. Trying to keep track of multiple complex projects at once pushes me right up to that limit.

In order to keep you focused on the important stuff right in front of you, your brain relies on those instant visual cues as you walk through the door. It’s not that it pushes that old memory out to make room for the new one so much as there’s a brand new visual context to consider.

Go back into that living room you were just in, and suddenly those older context clues are all around you. Even though you intended to go into the kitchen, the idea originated in the living room.