Maybe being a court jester is not all bad – you get to play music, which increases your brain’s gray matter and improves your general cognitive ability, and you get to entertain the court with your juggling skills, which you will find out, if you read the rest of this post, is also good for your brain.
In a 2004 Nature paper Draganski et. al., examined how practicing 3 ball juggling changed the brain. In a 2008 follow-up study by the same research group further explored this issue (Dreimeyer et. al., 2008: freely available – so I will concentrate on this paper). They again found an increase in gray matter in the occipital-temporal cortex with juggling practice.
They used 20 volunteers that had never juggled before and did a baseline T-1 weighted MRI brain scan. The subjects were then given 3 balls and instructed on how to juggle (3 ball cascade) (in the previous experiment they had a non-juggling control group that did not display any changes in gray matter over the experimental period). After each subject had demonstrated at least 60 seconds of ‘endurance juggling’ (I presume they mean the ability to continuously juggle for that time period) the brains were scanned again (7 days after starting to learn juggling). Additionally, the subjects were scanned after 7 and 28 more days, after they demonstrated 120 and 180 seconds of juggling respectively.
By as little of 7 days of juggling training there was an increase in gray matter density in the middle temporal area of the visual cortex ( hMT/V5) (the same brain region as reported in the 2004 paper) – important for visual spatial/motion tracking. They suggest that the increase in gray matter density doesn’t necessarily mean more neurons, but could occur for many reasons which include: increase in cell size, neural or glial genesis, spine density, or possibly changes in blood flow or interstitial fluid.
The increased in gray matter density were also observed at the later time points (14 and 35 days after starting juggling) which involved further improvement in juggling ability (120 and 180 seconds of continuous juggling) – however there were no further increases as you might expect with more practice and improved juggling ability. Additionally, they did not find that time spent practicing or juggling performance could predict the degree of change in gray matter density.
Summing up this proportion of the study the authors wrote: “We suggest the qualitative change (i.e. learning of a new task) is more critical for the brain to change its structure than continued training of an already-learned task.”
After the subjects had done the last scan after demonstrating 180 seconds of juggling they were told to no longer juggle. The subjects were scanned two more times, at 2 and 4 months after stopping juggling. When the subjects were brought in for scanning their juggling ability was tested and most subjects were still able to juggle, but not to the final two levels of proficiency. What is interesting is the previously juggling practice induced increase in gray matter density had disappeared during the non-practice time.
This sure seems to back up the old adage – use it or lose it.
Take home message:
Therefore, one of the best brain hacks is another age old adage: never stop learning – new things. As the authors pointed out it is the learning of a new task that is important, not the continued practice, for promoting the increase in gray matter which occurs by as early as 7 days. However, if you want to keep the new gray matter (and ability) you have to keep practicing. Therefore, you have the competing pulls on your precious time: learn new things to promote increase in gray matter – but to keep the gray matter you have to keep practicing the new task but also past novel tasks which you had learned (to keep the gray matter increase they induced).
Obviously there is a finite limit to how many new tasks/skills practicing you can keep up – hence you have to become a very good juggler. Those court jesters were really onto something it appears