When we enter a room, we often forget what we came in for. The reason is that doorways trigger a host of emotional scenarios which block out rather mundane things like picking up your slippers, or changing your socks.
According to psychologists (whose names I've forgotten), what we need to do, before we start, is to vividly imagine our slippers or socks hanging from the doorway. Then, when we go through the doorway to get whatever, we will 'see' our slippers or socks displayed provocatively on the door frame. And we will think "What the hell are they doing there?" This triggers another emotional reaction which helps to prioritize the cognition of the task in hand.
So next time we nip upstairs to get something, as we go through the doorway we will immediately think of socks and slippers. The fact that we went upstairs to change a light bulb means that we should never trust what scientists say.