[Researchers] used magnetic scanners to explore the brain activity of taxi drivers as they navigated their way through a virtual simulation of London's streets.[London] Taxi drivers 'have brain satnav' (BBC News, 13 Sept 2008)
Different brain regions were activated as they considered route options, spotted familiar landmarks or thought about their customers.
Earlier studies had shown that taxi drivers have a larger hippocampus - a region of the brain that plays an important role in navigation.
Their brains even "grow on the job" as they build up detailed information needed to find their way around London's labyrinth of streets - information famously referred to as "The Knowledge".
"We were keen to go beyond brain structure - and see what activity is going on inside the brains of taxi drivers while they are doing their job," said Dr Hugo Spiers from University College London.
When the going gets weird, the weird turn pro. - Hunter S. Thompson