How come after doing a motion to music, I'll continue doing it long after the music stops?

Like for instance, I was headbanging to some metal earlier, and throughout the day I've caught myself headbanging for no good reason. Same thing happens to me when I listen to ska music. When I listen to it, it sends my entire body in motion. However, when I'm sitting or laying down, my right leg will bounce up and down uncontrollably.How come after doing a motion to music, I'll continue doing it long after the music stops?The repetitive motion programs your muscles. This is called muscle memory. It's how we remember dances, martial art forms, athletic skills, or playing an instrument. Our body naturally wants to repeat this motion that brought us pleasure.