The Event Boundary Phenomenon.
Well the title sounds all very scientificy and everything so read on if you dare...
Have you ever entered a room and completely forgot what you were doing, or why you even entered the room in the first place? You will be happy to hear you're not alone, in fact, for the last 20 years, a Notre Dame scientist named Gabriel Radvansky has been searching for an answer as to why this happens, and now he believes he and his research team have come close to solving the problem, I'm not convinced there was a problem to be solved but still each to his own.
Radvansky used three rooms of his lab to test participants ability to remember what they were doing as they passed from room to room. In the experiment, passing through a door and into a new room caused participants to answer more incorrectly to the questions! This means that, for whatever reason, passing through a door made people forget what object they had just carried through it, where is his control to the experiment you may ask as without a control the results cannot be verified any dummy knows that.
The name for this phenomenon is "event boundary". Basically, (Apparently according to him that is.) our brains tie events into our environment, or a room that we are in when the events occurred. By moving to a different room, our brain simply puts the events and thoughts from the first room into a file, and tucks it away. When we enter the second room, our brain starts looking at the "file" for the second room! Personally I'm surprised I can even remember my own name every time I walk through a door but somehow I went to the kitchen 10 minutes ago to fetch a beer and can you believe it I came back to my study with said beer brilliant...
As has been written Radvansky calls this thing, "Event Boundary." I call it for fuck sake get a life mate, that's twenty bloody years you are never going to get back....