Learning a new, complex skill such as juggling has been found to boost connections between different parts of the brain, enhancing brain development. These connections remain in place, no matter how well the skill is learnt, suggesting the importance of the learning process itself for improving the mind.
The brain is largely made up of white matter and gray matter. White matter describes all areas of the brain that contain mostly axons - processes of nerve cells that connect various grey matter areas of the brain to each other, and carry nerve impulses between neurons. Grey matter areas forms the locations of nerve cell bodies in the brain.
Researchers from the University of Oxford discovered that learning to juggle tweaked the architecture of the brain's "white matter". They gave 24 young men and women training packs for juggling and had them practice for half an hour a day for six weeks. Before and after this training period, the researchers scanned the brains of the jugglers along with those of 24 people who didn't do any juggling, using a technique called diffusion tensor imaging that reveals the structure of white matter.
They found that there was no change in the brains of the non-jugglers, but the jugglers grew more white matter in a part of the parietal lobe - an area involved in connecting what we see to how we move.
The same transformation was seen in all the jugglers, regardless of how well they could perform. This suggests that it's the learning process itself that is important for brain development, not how good you are.
"It suggests that learning a skill is more important than exercising what you are good at already - the brain wants to be puzzled and learn something new."
The team found that both white and grey matter were necessary to learn this new skill:
"More white matter on its own might mean you can move more quickly, but you'd need the grey matter to make sure your hands were in the right place," they said.
The group scanned the jugglers' brains again after four weeks without juggling. They found that the new white matter had stayed put and the amount of grey matter had even increased. This could be why, when we learn a new skill, we retain some ability, no matter how long ago we last practiced.
Just like if we want to keep our bodies fit and healthy then we have to exercise, the same applies to our brains. To effectively exercise the mind the important point is to continually challenge it by learning new skills.
Scholz J, Klein MC, Behrens, TEJ, Johansen-Berg H. Training induces changes in white-matter architecture. Nature Neuroscience 12, 1370 - 1371 (2009)