Because of the moving conveyor belt graphic display in the video game Guitar Hero, playing it for any real length of time will result of a vision distortion known as "Hero Vision."

You really have to experience it to understand it, but basically it makes things stretch out.

Hero Vision is not exclusive to the Guitar Hero series, and can be induced by any game like it, such as the Rockband series.

The effect on your eyes and subsequently on the world around after prolonged exposure to Guitar Hero or other such music games, where everything appears to be moving towards you.