The study by the Wellcome Trust supports increasing evidence that learning can change the structure of the brain even in adult life, offering encouragement for lifelong learning and the potential for rehabilitation after brain damage, a release Thursday by the trust said.
To qualify as a licensed London taxi driver, a trainee must acquire "the Knowledge" of thousands of streets and their idiosyncratic layout, training that takes three to four years and culminates in a stringent set of examinations that must be passed to obtain license.
Only around half of trainees are able to meet the requirement, unique among taxi drivers throughout the world.
Studies have shown greater volume of gray matter in an area known as the posterior hippocampus in those who complete the process relative to non-taxi drivers.
"The human brain remains 'plastic,' even in adult life, allowing it to adapt when we learn new tasks," Eleanor Maguire, a Wellcome Trust Senior Research Fellow, said. "By following the trainee taxi drivers over time as they acquired 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," she said.