We’ve lost direction and our brains are shrinking – at least, our hippocampi are. These seahorse-shaped parts of the brain measure about 5cm, sit just above both ears and drive our spatial awareness and orientation. London taxi drivers, famed for taking the Knowledge, a test that involves memorising the central streets of the capital, have full-sized hippocampi. But in 2011, neuroscientists at University College London discovered that the cabbies’ hippocampi shrunk significantly after retirement.
The development of the hippocampus can also be stunted in childhood. Children living in urban environments rarely see the sun rise or set and cannot tell the difference between east and west. When I volunteered to go into my local school to teach kids about direction, I found they struggled to distinguish north from south and east from west – though they could do so if allowed to use their phones.
