Unfortunately our schools, colleges, businesses, and culture have, for hundreds of years, been built around the idea that some people can and some people can’t. This is why putting young students into different groups and teaching them differently made perfect sense. If individuals within a school or company weren’t reaching their potential, it was not due to teaching methods or environmental factors, but to their limited brains. But now, with decades of knowledge about brain plasticity, it is time that we eradicate this damaging myth about learning and potential.
Energized by the new evidence showing brain plasticity in animals, researchers began to look at the potential of human brains to change. One of the most compelling studies of the time came from London, the city where I had my first teaching and university job. London is one of the most vibrant cities in the world—and it is always filled with millions of residents and visitors. On any day in London you will see “black cabs” zipping around the thousands of major thruways, streets, and lanes. The drivers of these iconic taxicabs hold themselves to very high professional standards. Londoners know that if they get in a black cab and tell the driver a road to find, and the driver does not know it, the driver should be reported to black-cab authorities.
Knowing all the roads in London is quite a feat—and drivers go to huge lengths to learn them. In order to become a black-cab driver, you need to study for at least four years. The most recent cab driver I traveled with told me he had studied for seven years. During this time drivers must memorize every one of the twenty-five thousand streets and twenty thousand landmarks within a six-mile radius of the centrally located Charing Cross station—and every connection between them. This is not a task that can be accomplished through blind memorization—the drivers drive the roads, experiencing the streets, landmarks, and connections, so they can remember them. At the end of the training period, the drivers take a test that is aptly named “The Knowledge.” On average, people have to take the test twelve times in order to pass it.
The extent and focus of the deep training needed by black-cab drivers caught the attention of brain scientists, who decided to study the brains of the black-cab drivers before and after the training. Their research found that, after the intense spatial training, the hippocampus of the cab drivers’ brains had grown significantly.4 This study was significant for many reasons. First, the study was conducted with adults of a range of ages, all of whom showed significant brain growth and change. Second, the area of the brain that grew—the hippocampus—is important for all forms of spatial and mathematical thinking.
Researchers also found that when black-cab drivers retired from cab driving, the hippocampus shrank back down again—not from age, but from lack of use. This degree of plasticity of the brain, the amount of change, shocked the scientific world. Brains were literally growing new connections and pathways as the adults studied and learned, and when the pathways were no longer needed, they faded away.
