Answer:
Brain uses internal compass for keeping track of which direction we are facing.We have an internal compass, always keeping track of which direction we are facing, and always keeping track of changes in that direction. The brain can use this compass to guide the way. Just like your GPS device keeps track of each turn you make in the car so it can sulkily work out the new route from the direction you are now facing. (Unlike satnavs, our brains don't constantly narrate our wrong turns with barely disguised sarcasm. Well, mine does, but I suspect that's not normal).