You’re high up on a snow-covered mountain, wind whipping through your hair as you ski past a blur of pine trees down towards a pristine alpine lake. The terrain suddenly dips and a bolt of fear sprints up your spine as your eyes widen at how steep the slopes look. Your instincts take over, and you start to pull back, to shift your weight to your heels and run from danger. But just before you fall on your butt, your brain kicks in and you remember to lean forward to keep from falling, and you accelerate down the hill, in from the ride of your life.