If you follow the paintbrush with your eyes while not moving your head, it forces you to use EMDR which is a therapeutic technique to calm anxiety/panic. Watching fish swim causes the same effect.
I found this through Tumblr a while ago and thought it was relevant for today. Not sure if it’s true but I’m already having a crazy, stressful day and it’s not even 9am yet! So it’s worth a try 🙂