When I first learned to juggle, my teacher, a man whose workouts consisted of running for miles while juggling which he called “joggling,” told me that juggling changes your brain and gives you more gray matter. This meant pretty much nothing to me at the time, but it wouldn’t be the first time neuroscience and juggling collided in my life.
While I was visiting Emory for recruitment, I told some students that I liked to juggle for what I’m sure were totally relevant reasons. During a break between interviews, I was asked to prove it, and while juggling some squishy tangerines, one of my hosts (who has since graduated) decided to chuck a couple more tangerines at me for what I’m sure were equally sound reasons. The tangerines exploded all over my interview clothes, and for the rest of the weekend I was known as the recruit who Dave threw an orange at.
My teacher had only gotten it partially right about juggling and gray matter; a lot of things change our gray matter. The interesting thing about juggling is that it was the exercise used to show long term changes in white matter for the first time in a paper by Heidi Johansen-Berg in Nature Neuroscience in 2009. Twenty four adults were given a six-week course in juggling, and then made to quit their new skill for four weeks. Diffusor Tensor Imaging (DTI) was performed before and after their training, and then again after their juggling abstinence, and it was found their white matter increased after training and stayed increased during juggling prohibition. The regions that were affected are involved in arm movement, grasping, and peripheral vision, which makes sense, but interestingly the magnitude of changes had no relation to the level of skill reached. Juggling enthusiasts have since used this paper to claim that juggling makes you smarter, sharpens concentration, and can prevent neurodegenerative diseases, though it’s hard to take anything seriously from people who literally run five miles a day through forests while juggling.
I personally believe that juggling was responsible for my admission to Emory, though probably not because it enhanced my brain connectivity. I just think getting pummeled with rotten fruit during interviews makes one memorable and leaves a favorable impression. But if anyone wants to increase their gray AND white matter, I can teach you to juggle and promise not to throw any fruit at you.