UCL aims to help drive the fight against dementia by enlisting London’s Black Cab drivers in a unique brain testing trial.
London’s black cab drivers, famed for their ability to plan routes by remembering thousands of the capital’s streets, are playing a vital role in advancing dementia research. The Taxi Brains Project, run by The Spatial Cognition Group at University College London, is analysing taxi drivers’ brains via MRI scans as they plan routes through London.
Longevity.Technology: Possessing a larger part of the brain that shrinks early in Alzheimer’s disease – the hippocampus – licensed black cab drivers are a unique test group and the results of the trial will help provide critical insights in helping science to develop diagnostics to detect Alzheimer’s disease earlier.
Alzheimer’s disease is by far the most prevalent degenerative dementia, and there are nearly 10 million new cases every year [1]; the disease is an enormous burden globally, both for patients, families and healthcare systems, and there is no known cure. Understanding more about the way the disease takes hold and being able to identify it earlier will lead to better outcomes for sufferers as well as progress towards improving therapy.
By completing the Knowledge of London, acquired through years of training in specific Knowledge Schools, London’s cabbies learn to navigate through the city’s 58,000 streets without the use of GPS and automated instructions.
As well as always having had a famous person in the back of their cab once, London’s taxi drivers have another remarkable feature – their brains have larger hippocampi [2].
The hippocampus is essential for forming new memories, such as who was on the ‘phone or what you needed to add to your shopping order. However, Alzheimer’s patients suffer progressive shrinkage of the hippocampus, and this is responsible for the short-term memory loss that is one of the hallmark symptom of Alzheimer’s disease.
“Understanding which parts of the hippocampus get bigger in relation to navigation ability will provide critical insights needed to help develop diagnostics for the earlier detection of Alzheimer’s disease,” explains the Taxi Brains Project. “Early diagnosis will help doctors treat patients sooner, limiting the disease and improving quality of life [3].”
Taxi drivers plan a variety of different routes on the fly on a daily basis; they also have to adapt to changing circumstances such as weather, roadworks and capricious customers. This planning from memory and being able to retain such a vast amount of details has an incredible impact on taxi drivers’ brains. A study discovered that the hippocampus, which is also involved in spatial navigation, is larger in taxi drivers that non taxi drivers [2].
Additionally, research has demonstrated that the hippocampus seems to be part of the brain affected in Alzheimer’s sufferers; this might explain why a symptom of the disease is disorientation and an inability to find their way, sometimes even becoming lost just metres from home. These symptoms often increase in severity as the disease progresses [4].
[1] https://www.who.int/news-room/fact-sheets/detail/dementia
[2] https://www.pnas.org/content/97/8/4398
[3] https://spierslab.com/taxi-brains-project/
[4] https://pubmed.ncbi.nlm.nih.gov/25913063/
