Whose brain would you rather have? That of a bus driver or a taxi driver?
A few neuroscientists decided to take that question seriously. They compared the brains of London cab drivers and taxi drivers, while controlling for driving experience and stress levels. They found that the taxi drivers had more grey matter in their hippocampi (singular: hippocampus). Their brains literally grew on the job, giving them an ability to snake the city’s intricate nooks and crannies.
It is interesting that driving experience did not correlate to this change in the brains structure. Nor did stress levels. Both taxi drivers and bus drivers spend hours on roads amidst stressful traffic. It’s just that while one of them drove around new parts of the city each day, the other followed a fixed set of routes. It isn’t as much about how much of something you do. It is about how demanding the task inherently is.
If your practice feels entirely comfortable, you might not be learning. On the other hand, if it causes your head to hurt, take that as a good sign – of the brain strengthening existing neural pathways or forging new ones. Also, long hours on your job doing the same task do not develop your brain as much as new ones do.