when you are in room
one and you think of
something you need to get in room two, you walk to room two and forget what it was you where doing/getting in that room.
the below is cerebral originitis:
when you go back to room
one you immediately remember why you went in room two in the first place.
this can happen many times in a row when you keep remembering and forgetting. this is called (number)fold originitis.