I grew up well before the GPS age so it also seems foreign to me that there are people who can't navigate without one. I generally know to a pretty good degree of accuracy the cardinal directions (N,S,E,W) and if I've been somewhere once I can generally find it again. It would be interesting to do brain scans on people of different ages while they're doing spatial navigation to see the differences in the brains of those who grew up with GPS vs those who didn't.