If it's on FastCo, it must be true. Right up there with daydreaming, doodling is now being touted for it's mind-freeing attributes. According to FastCo, recent scientific research indicates that seemingly absent-minded tracings can help the brain process and retain information and solve problems. While doodling can improve retention for information that you're hearing, it doesn't always work when trying to remember visual images while doodling.
Personally I'm a fast, manic, somewhat messy doodler. My doodles combine my lists for the day, product ideas, show booth ideas, and usually architecture or faces. Often when I look back at them it takes me awhile to even figure out what they ARE, which is fine as the very nature of doodling is that they don't have to be ABOUT anything. (The Virgo in me always feels like I have to be accomplishing something, so I look back at the doodles in hopes that some stray hair of genius somehow escaped and landed on the page as a really fantastic concept.)
Here's some of my doodles--although showing them to you feels a bit like going to the grocery store in a swimsuit. What do your doodles look like? Are you more of a Zentangular person or a structured sketcher?