The new science of how we walk and why it’s good for us
This is a snippet from the book, In Praise of Walking by Shane O’Mara, which examines the science behind one of the basic skills that defines us as human beings.
Scientists are slowly working out how our sense of direction works.
It’s not just the mechanics of walking that requires brain power. There’s also the question of how we actually know where to go.
Put yourself in the author’s shoes. It’s a good few years ago, before the age of smartphones. You have to walk from North London – Highgate, to be precise – all the way back to your home in Streatham, which is a long way south. You don’t have a map.
How do you do it? Well, essentially, you channel your inner homing pigeon. Dead reckoning, otherwise known as path integration, is our innate ability to move in the right general direction toward a destination.
But as for how that works – scientists are only just coming to grips with it.
The key message here is: Scientists are slowly working out how our sense of direction works.
Strolling right through the heart of London, across the river Thames and down through the south, the author managed to find his way home – even though he was going through areas he didn’t know. He was able to do this because finding our way around isn’t wholly dependent on visual cues.
Several studies have proven that our spatial sense is not greatly affected by our ability to see. In tests measuring a sense of direction, blindfolded people and people with visual impairments performed similarly to those with “normal” sight.
The neuroscientist John O’Keefe has made some pioneering discoveries regarding how the brain determines where we are. He discovered that when rats wander to a place they know, particular cells around the brain’s hippocampus light up. Different cells light up when they move somewhere else. These are known as place cells – they tell us where we are. Humans have them too, and they work most effectively when we walk.
Further research has revealed even more fascinating types of cells in the brain that help us get around. Head-direction cells are essentially an inner compass, indicating our orientation. There are also cells that respond to nearby objects. The author himself has worked on perimeter cells, which respond to the boundaries that surround us.
All in all, the brain more or less has its own GPS network, constantly updating itself as we are walking around.