I've had similar thought patterns since I was kid (24 now). I think it's similar to the game many kids play "the floor is lava" (where you have to avoid stepping on the floor and then get from point A to B; if you step on the floor you 'die'). So it's partly a function of the imagination. Though more recently I've used it while being more conscious of what I am doing. Maybe, instead of having the effect wane, it's become more controlled and intuitive the more I've done it.