A couple of years ago, British researchers discovered that London cabbies have particularly beefy brains. Their study, which followed 79 trainee taxi drivers and 31 non-taxi drivers (the controls) for three to four years as they got acquainted with London’s winding and congested streets, discovered that the taxi drivers eventually developed notable differences in their posterior hippocampi—changes not found in the brains of the controls. (The hippocampus, as the neurosurgeons among us will recall, manages the brain's memory tasks, including navigation.)
At the end of the study, even those taxi drivers who failed to pass their training tests were significantly better at memory tasks involving London landmarks than the control group. Maybe that's not surprising: Over the course of their driving, these cabbies learned London.
So what does all this have to do with UberX? Here in Washington, D.C., where the low-cost ride-hailing service has been around since August 2013, UberX generally works something like this: You request a car through the app, and a clean, mid-size vehicle shows up a short time later, piloted by a polite but confused driver from the suburbs. He asks where you're going, but really needs an address, because he's not very familiar with the city. He plugs your address into his GPS device, and away you go.
The obvious problem here is that GPS isn't always the most efficient way to navigate through a congested city. GPS won't remind you that it's closing time at the big club on K Street, which will create a traffic jam at the unlikely hour of 2 a.m. It won't tell you when the Nationals game is getting out. It won't tell you to avoid packed Connecticut Avenue below Dupont Circle under any and all circumstances.
UberX drivers do not have to take a knowledge test to begin with the company. (In fairness, drivers licensed by the D.C. Taxicab Commission are merely encouraged during training to "take time to know historical landmarks, events and restaurants," though in my experience, D.C. cab drivers are far more knowledgable than UberX drivers.) And since a GPS-enabled smartphone is required to download and use the UberX app, UberX drivers are by definition outfitted with vehicle navigation technology.
The issue, however, is not that UberX drivers don't know the city when they begin driving—though that's certainly inconvenient for their first crop of passengers. Scientific research suggests that drivers who rely on GPS might never learn the city.
Work by neuroscientist and McGill University researcher Veronique Bohbot indicates that drivers who use GPS technology regularly could end up negatively affecting their hippocampi and, consequentially, their abilities to navigate. According to Bohbot's research, there are two ways of navigating. Spatial navigation methods are what we might use without GPS—using landmarks and visual cues to create cognitive maps that help us orient ourselves and get where we want to go. Stimulus-response navigation, however, is triggered when we go on "auto-pilot," thoughtlessly following a path because we've either done it before or are following the directions of our handy GPS devices.
By conducting fMRI scans on older GPS and non-GPS users, Bohbot and her team found that GPS users had less well-developed hippocampi. That suggests that GPS users don't form the same kind of complex cognitive maps that allow London taxi drivers, for instance, to zip through their city.
There's more evidence that GPS drivers don't learn as well as traditional navigators. In 2005, the University of Nottingham's Gary Burnett asked study participants to complete four separate but overlapping routes using a driving simulator. Half of his participants were given paper maps to navigate; the others received step-by-step instruction, as they would with a GPS system. Burnett and his team found "strong evidence" that GPS systems negatively affect the formation of drivers' cognitive maps. Drivers who received the step-by-step instructions remembered fewer scenes from their drives, had difficulty ordering images seen along their routes, and, when asked afterwards to draw their paths, provided simpler maps with fewer landmarks than those using paper maps.
Burnett's GPS drivers, in other words, hadn't internalized their routes. “[D]rivers in the traditional condition were actively paying more attention to the driving environment,” Burnett and his team wrote.
A team of University of Tokyo researchers observed a similar phenomenon when they asked groups of people to navigate an urban environment both with and without GPS systems. GPS users, they found, traveled longer distances, navigated more slowly and made more stops than their map-toting brethren.
Of course, GPS has its advantages. Horror stories of confused drivers heading straight into train tracks aside, the technology is usually accurate. Burnett and his team also found evidence that vehicle navigation systems reduce driver stress, which could lead to safer driving.
But if you're hoping to get to your destination quickly and smoothly—if, say, a taxi meter is running—a driver who depends on GPS might not be your best bet.
Not every city where Uber operates has the exact same UberX issue. But for metro areas like D.C., where suburban drivers tend not to know their way around the city very well, Uber suggests it has a fix. "Our rider and driver rating system provides an incentive for Uber driver partners to learn the city quickly and become more efficient at navigating the streets," says Uber spokesperson Taylor Bennett in an email. "Riders rate and provide comments about their experience at the end of every trip, so this provides a level of accountability and ensures we have the highest quality driver partners on the road."
So if you care about the quality of your ride—not to mention your UberX driver's hippocampus—get stingy with stars.