Walking through doorways make us forget why?

Forgetting why you entered a room is called the “Doorway Effect”, and it may reveal as much about the strengths of human memory, as it does the weaknesses, says psychologist Tom Stafford.We’ve all done it. Run upstairs to get your keys, but forget that it is them you’re looking for once you get to the bedroom. Open the fridge door and reach for the middle shelf only to realise that we can’t remember why we opened the fridge in the first place. Or wait for a moment to interrupt a friend to find that the burning issue that made us want to interrupt has now vanished from our minds just as we come to speak: “What did I want to say again?” we ask a confused audience, who all think “how should we know?!” We can appreciate those temporary moments of forgetfulness may be more than just an annoyance
Although these errors can be embarrassing, they are also common. It’s known as the “Doorway Effect”, and it reveals some important features of how our minds are organised. Understanding this might help us appreciate those temporary moments of forgetfulness as more than just an annoyance.

These features of our minds are perhaps best illustrated by a story about a woman who meets three builders on their lunch break. “What are you doing today?” she asks the first. “I’m putting brick after sodding brick on top of another,” sighs the first. “What are you doing today?” she asks the second. “I’m building a wall,” is the simple reply. But the third builder swells with pride when asked, and replies: “I’m building a cathedral!”By the time you’ve reached the fridge, you have forgotten why you were there – but rather than being a weakness, this may reflect complex brain processing Maybe you heard that story as encouragement to think of the big picture, but to the psychologist in you the important moral is that any action has to be thought of at multiple levels if you are going to carry it out successfully. The third builder might have the most inspiring view of their day-job, but nobody can build a cathedral without figuring out how to successfully put one brick on top of another like the first builder.As we move through our days our attention shifts between these levels – from our goals and ambitions, to plans and strategies, and to the lowest levels, our concrete actions. When things are going well, often in familiarsituations, we keep our attention on what we want and how we do it seems to take care of itself. If you’re a skilled driver then you manage the gears, indicators and wheel automatically, and your attention is probably caught up in the less routine business of navigating the traffic or talking to your passengers. When things are less routine we have to shift our attention to the details of what we’re doing, taking our minds off the bigger picture for a moment. Hence the pause in conversation as the driver gets to a tricky junction, or the engine starts to make a funny sound.
The way our attention moves up and down the hierarrchy of action is what allows us to carry out complex behaviours, stitching together a coherent plan over multiple moments, in multiple places or requiring multiple actions.
The Doorway Effect occurs when our attention moves between levels, and it reflects the reliance of our memories – even memories for what we were about to do – on the environment we’re in.
source:BBC