To become a cab driver in London, you have to acquire "The Knowledge," which is their fancy way of saying that you have to memorize all the streets in London. It's quite a process that takes most three to four years to complete.
Now, scientists have found that studying for the test makes your brain bigger. The U.K. Press Association reports:
"Researchers who followed a group of trainee taxi drivers found that gaining "The Knowledge" can alter brain structure.
"But this only occurred in those who successfully qualified after spending up to four years memorizing London's 25,000 streets and myriad landmarks. Scans revealed they had a greater volume of "grey matter" at the back of the hippocampus, a brain region known to play key roles in memory and spatial navigation.
"Grey matter consists of the "bodies" of nerve cells and is where neural processing takes place."
According to Nature, scientists looked at 80 trainees. Scientists took brain scans before they started studying. After about four years, half of them acquired "The Knowledge," while the other half dropped out. After scanning the succesful brains, scientists found the hippocampus was bigger.
So the study tells us that becoming a cabbie in London is hard work, but it also tells us that learning can continue into adulthood.
"Prof Eleanor Maguire, who led the study, said: 'The human brain remains "plastic", even in adult life, allowing it to adapt when we learn new tasks.
"'By following the trainee taxi drivers over time as they acquired - or failed to acquire - the Knowledge, a uniquely challenging spatial memory task, we have seen directly and within individuals how the structure of the hippocampus can change with external stimulation.
"'This offers encouragement for adults who want to learn new skills later in life.'"
The new research is published in the latest issue of the journal Current Biology.