I was at a Twenty One Pilots concert where they chose some people from the audience to participate in a competition about who could eat a raw potato the fastest and then they went on to play so passionately they completely demolished their instruments.
This still image was created by a Japanese neurology professor Yamamoto, and he told the instructions below: If its not moving, or just moving a little, you are healthy and has slept well. If its moving slowly, you are a bit stressed or tired If its moving continuously, you are over-stressed