London cabbies have been an iconic fixture in any London street scene for decades. Now the black taxi cab and their extraordinary cabbies are the focal point of a new expedition into Alzheimer’s research.

Cabbies have an incredible knowledge of London streets that seems to confer some protection against Alzheimer’s Disease—this could be clinically relevant to struggling patients, or those seeking to mitigate their risks.

Since 1865 London cabbies have been required to pass a difficult test known as “the Knowledge” to prove that they can find 100,000 businesses and landmarks in a labyrinth of tens of thousands of streets.

The series of exams — which take three to four years to complete — have been hailed as possibly the most difficult memorization test in the world. To be fully licensed to drive anywhere in London, a cabbie needs to know how to plot routes without a GPS on about 26,000 streets spanning a six-mile radius from London’s center point.

But London cabbies’ skills are now being tested for a different reason: to determine whether their brains hold clues that might be applied to Alzheimer’s research. A project called Taxi Brains is underway at University College London to study the brains of London cabbies as they map out taxi routes while undergoing MRI scans. The hippocampus regions of taxi drivers’ brains — which play an important role in learning and memory — appear to grow larger the longer the drivers are on the job while the same region is known to shrink in people with Alzheimer’s.

Research lead, Prof. Hugo Spiers said, “Maybe there’s something very protective about working out your spatial knowledge on a daily basis, like these guys do. It may not necessarily be spatial, but just using your brain rather than Google Maps might actually help—in the same way that physical fitness is important.”

Possible Preaching Angle:

God’s Word also confirms that Scripture memorization is crucial to our spiritual health. We must not use Google, smartphones, and the Internet as a crutch in “hiding God’s Word in our hearts” (Psa. 119:11).