Almost everything we do changes the physical structure of our brains, including what we think about. Each time you recall a memory, for instance, you are effectively strengthening the connections between brain cells. Skilled activities, like playing musical instruments or playing chess, are associated with larger changes to the size of specific brain regions. For example, violinists have more brain tissue dedicated to representing the fingers of their left hand, and expert chess players have reduced grey matter – a possible sign of efficiency – in an area associated with representing how objects are related to each other.
