Ever walk into a room and forget what you were doing? - Gabriel Radvansky

You enter your living room, then pause. You feel your mission’s momentum— but its aim is suddenly lost. So, what just happened? And why does it keep happening? Well, you’re not alone; this is actually a common phenomenon scientists have termed the doorway effect. According to psychological models, our brains parse life’s continuous flow of time and activity into distinct events.

As a situation unfolds, the brain develops a working model of the event. It likely does this by employing its default mode network, the brain regions that work together to accomplish many resting thought processes. Then, when there's a big enough change, the brain is thought to identify an event boundary, at which point it stores the prior event model,

and begins developing a new working model. During this switch, called an event update, parts of the default mode network seem to interact with the memory-storing hippocampus, perhaps transporting the experience into longer-term memory. In the process, the brain clears its short-term memory, making room for the new information that’s already pouring in. But sometimes that can be stuff you weren't quite done with.

It’s still not fully clear if the doorway effect, also called the location updating effect, befalls some people more than others. But one study found that age had very little bearing. Scientists are working to better understand the phenomenon by pinpointing the conditions that trigger it, which, yes, includes doorways, both physical and virtual. In one study, college students in real and virtual spaces

were asked to pick up objects, walk set distances carrying them out of view, then try to recall what they were holding. Time and distance remained constant, but some traveled through a doorway. Those who did tended to respond slower and be more likely to forget. And passing through multiple doorways seems to worsen the memory-thwarting effect.