"People may doodle as a strategy to help themselves concentrate," said study co-author Jackie Andrade, a University of Plymouth psychologist. "We might not be aware that we’re doing it, but it could be a trick that people develop because it helps them from wandering off into a daydream." Read more here.
I used to doodle with a pen on a paper when talking on the phone, and I still doodle, during boring meetings mostly. I have been in many boring meetings. Some people in meetings have a knack for repeating things over and over, saying the obvious, and not listening to what was said just a few minutes before. They would probably have been better off if they had doodled more. What I doodle? Oh, grasses, sedges in water, geometric figures, inca temples, coral like shapes, tiny flowers, spirals and diamonds, alpine mountains.... hmmm, sounds like everything is very scientific. I don't doodle steam engines, horses, faces, or sushi, but I am sure others do.. I wonder how the brain decides what it want to draw, how the things come out through the pen.