Driving one of the famous London’s black cabs is not an easy feat; you have to show you’re up to it. And to do that, you must show that you know every one of the single 25,000 streets of the city center, as well all the major landmarks that populate the space. And after you gather all this knowledge you also have to show that you can recreate by heart the route between two given streets, step by step not forgetting to mention every single statue along the way.
This exhausting process to obtain a black cab license is known as The Knowledge, and it usually takes 2 to 4 years for an applicant to obtain it through a serie of tests are points are won. But taking and aquiring The Knowledge not only gets you a license, it changes your brain. Or more correctly, it changes a part of your brain known to be related with spacial memory:
In 2000, Maguire showed that one particular part of the brain – the hippocampus – is much larger in London cab drivers than in other people. This seahorse-shaped area lies in the core of the brain, and animal studies had linked it to memory and spatial awareness. Species that store a lot of food tend to have a bigger hippocampus than those without the need to remember any burial sites.
Maguire showed that the same applies to humans. Not only did cab drivers have an unusually large hippocampus, but the size of the area matched the length of their driving careers.
Furthermore, the studies that have been conducted over the years on this subject as shown that it’s the aquisition of The Knowledge and its practice that changes the hippocampus size and not the fact that one has an abnormally (compared to mean) large hippocampus that allows the aquisition.
This is further proof of brain’s plasticity through learning even after adulthood and can have an important role in the study on how can we deal with diseases such as Alzheimer.
You can read more about these studies here.