(Image source: Wikimedia Commons)

BY STEVEN SPARKMAN

Let’s say you’re on a rock ‘n’ roll tour of London. You’ve just taken a photo of yourself strolling across Abbey Road, and now you want to pose in a red phone box on Heddon Street like Ziggy Stardust. Don’t know the way?

The London Black Cab driver does. And Popular Science explains, a new study shows that cabbies’ mental map of London is so detailed, it alters their brains. (Image source: Wikimedia Commons)

“London cabdriver tests are notoriously difficult and complete. You don't just pass the test -- you earn ‘The Knowledge,’ or the ins and outs of a massive and complex city from end to end. And, it turns out, the level of training needed to pass the test actually changes the structure of the brain...”

For the unfamiliar, London is not laid out in a logical grid. If you pulled your holiday decorations out of storage recently and found the lights all wadded up in a ball, it’s kind of like that. To get a job navigating the city, you have to pass a demanding exam.

A writer for Discover Magazine explains.

“Ever since 1865, they’ve had to memorise the location of every street within six miles of Charing Cross -- all 25,000 of the capital’s arteries, veins and capillaries. They also need to know the locations of 20,000 landmarks -- museums, police stations, theatres, clubs, and more -- and 320 routes that connect everything up.”

Researchers were curious whether that much memorization affects the brain. So, they followed 79 drivers-in-training as they attempted to earn “The Knowledge,” and mapped their brains using MRIs along the way.

A writer for io9 explains the results.

“At the beginning of the study … no significant differences in general intellect, powers of recollection, or brain structure could be identified... Three to four years later ... trainees who had qualified had experienced an increase in gray matter in the back part of the hippocampus, a region of the brain which plays a crucial role in memory and spatial navigation...”

The researchers say this is more evidence that the brain can adapt to new tasks even as an adult. But there was a price to pay: trainees who passed their tests actually fared worse than average on visual memory tests.

And another scientist who spoke to a driver learned there are social sacrifices, too.

“When you do The Knowledge, you forget about everything. You forget about your social life, you forget about your house, you forget about holidays, you forget about keeping in touch with your mates. It’s just constantly, constantly Knowledge, Knowledge, Knowledge.”

The price of The Knowledge? According to online estimates, that rock and roll photo trip will cost passengers about £14 in heavy traffic. But maybe the driver knows a shortcut.