Finally, proof that reliance on a GPS system really does rot your brain.
Researchers at McGill University in Toronto recently reported the results of a test that suggests reliance on GPS navigation may lead to reduced brain function. The researchers took brain scans of adults who were GPS-users and those who were non-GPS users. They found that those who didn't use the devices were found to have higher activity and a greater volume of grey matter in the hippocampus than those who relied on GPS. These adults also did better on a standardized test used in the diagnosis of mild cognitive impairment, which often precedes the onset of Alzheimer’s disease.
This comes on the tail of a study released in 2000 by scientists at University College London that showed that London taxi drivers given brain scans had a larger hippocampus compared with other people. That study also found that the hippocampus grew larger as the taxi drivers spent more time in the job.
Now Boston isn't London, particularly when it comes to driving a cab. In Boston, prospective cabbies take a 10-hour course that ends with a test in which they have to answer brain twisters like "True or False: It's okay to rush customers. That way you have more time for other fares." In London, prosective cabbies have to pass a three- to four-year course which involves learning the layout of 25,000 streets in the city center. Called "The Knowledge," three quarters of those who start the course end up washing out. Still, Boston has its challenges and as I've mentioned before, while a GPS will get you where you want to go, it won't get you there necessarily the fastest or even the shortest route.
All this doesn't mean NASA is going to start recruiting astronauts from the ranks of cab drivers and I'm not going to be a professor at Harvard, but it's interesting to think how all this might correlate with the increasing reliance on similar technology in other professions--say, flying an airliner. I'm not about to get rid of my GPS, but I think I'll turn it off once in a while.