Running: Look down or straight ahead?

Now this isn't about a self-esteem issue mind you. When I walk, I walk tall (or as tall as my 5'7" stature will allow me anyway) and look straight ahead. But when I run, I'm definitely looking down, from my feet to maybe a foot or 2 ahead, only looking up/straight ahead every few minutes. At first I was wondering if it was in fact a self-esteem thing coming through, but the reality is I don't like seeing how far I have to go. If I just look up every few minutes, I surprise myself with how far I'd already gone and before I know it, my run is over.

Anyway, I don't even know if this is a conscious thought for anyone else, but I was just wondering.