Chapter seven memory London taxi drivers memories London's taxi drivers must pass a grueling exam called the knowledge which tests their mastery of this complicated and detailed city because of the nature of their job these drivers have superb memories making them ideal subjects for a study on memory brain functions London's legendary taxi drivers are the Olympic athletes of memory navigating the intimidating labyrinth that is central London they must create an intricate mental map consisting of thousands of streets landmarks and locations London is such an enormous city it's a massive area chaotic geography and it's grown up organically there's no real planning to it so the streets bein like Swiss when somebody gets in your cab they'll say take me to the sound so it's it's going to be like that you've got to know instantly where you're going which way to be pointed so there's a lot of retention you've got to retain a lot of what you've learned as well retaining or remembering the twists and turns of London is key to the success of its taxi drivers scientists believe that the key to memory in turn lies in a region of the brain called the hippocampus the hippocampus is a part of the brain deep in the brain it's on the insides of what we call the temporal nodes which are the parts that brain immediately took you know either side of the temple just behind the bone there there's two structures one on each side critical for laying down new memories it would stand to reason then that the hippocampus --is of London taxi drivers must be very well-developed researchers at the University of London wanted to find this out for sure so they examined brain images of people training for the knowledge as well as those of drivers who have been on the job for a while math Romney to the nearest police station they bar all willing breach of Lancaster place drivers and training give their brains a good workout at the knowledge point school right York Way lifts Shaftesbury Avenue lifts great wind Mill Street what an open set down there after class students like Andy Miller take to the streets is not of learning all the roads then you have to learn all the places on every road with all the roofs that you have to do for the knowledge you couldn't possibly do on the map you have to get that with your bike in the rain the cold the snow you learn it bit by bit the brain is gradually countering more normal information as long as you keep remembering their opposing streets they won't stay near brain as the scientists suspected mastering the knowledge seemed to have a physical impact on the brain itself their study concluded that part of the hippocampus was indeed larger than average in these drivers in fact the most dramatic differences were seen in drivers who were on the job the longest the hippocampus has a spatial map in it and what seems to be happening in the taxi drivers is that the spatial map is laid down of central London and laying this down causes the connections to develop and grow and more of them to form and that makes the part of hippocampus get bigger this study suggests something we presume not possible that parts of the adult brain can actually grow once people wouldn't have dared to dream the human brain might possess this kind of adaptability but the London taxi drivers study has given scientists reason to hope perhaps one day doctors can use these insights to help restore the minds of stroke victims Alzheimer's patients and those suffering brain traumas what did scientists discover about the memory and brain function of London's taxi drivers and what implications could these findings have for future research