"Studies have shown that doodling can free up short- and long-term memory, improve content retention and increase attention span. It can also produce creative insight, because 'when the mind starts to engage with visual language, you get neurological access that you don’t have when you're in a linguistic mode,' says Brown. 'Most of us use reading, writing, and talking to brainstorm, but "the human mind is very habit forming,' she says. To break that habit, you have to think in an unfamiliar medium--a visual medium."
"Here's Why, How, and What You Should Doodle to Boost Your Memory and Creativity" by: Jennifer Miller via Fast Company. This article references a lot of thoughts by Sunni Brown. For more of her work and research on doodling, check out her website here.