Human beings have traversed and mapped continents and oceans. We’ve been to the Moon and back. We have an impressive collective knowledge about how to get around – but as Christopher Kemp’s fascinating book about the neuroscience of navigation shows, most of us still have a lot to learn about why we’re able to work out where we are.
Fortunately, there’s now plenty of scientific research to help out. In 1948, the behavioural psychologist Edward Tolman made a breakthrough that Kemp claims ‘rivals splitting the atom, or the discovery of the helical structure of DNA’. Tolman published a paper entitled ‘Cognitive Maps In Rats And Men’, which was based on a series of maze experiments that showed that rats don’t just learn a route, they’re also able to build ‘informative spatial representations’ of mazes in their heads. Animals don’t just learn directions, in other words, they build internal maps – and interact with them and modify them as they move around the world.
Kemp details many of the studies that have helped us understand these cognitive abilities. These range from ingenious low-fi experiments involving tracing people’s progress through Hampton Court maze using bags of flour with holes in them, to advanced set-ups involving virtual reality and functional magnetic resonance imaging. He imbues all of them with the thrill of discovery – while also building up a useful guide to what we know about the workings of the mind.
We learn about the populations of cells that perform ‘very different functions’ to help us navigate. There are place cells (which code information on location), grid cells (which help with direction and distance) and head-direction cells (which work like an internal compass). These interact in numerous varied ways within different regions of the brain – including the hippocampus, the prefrontal cortex, the parahippocampal place area, the entorhinal and retrosplenial cortices, and the caudate nucleus – providing us with a ‘constantly unfolding map of the world’ and helping us to navigate it, drawing upon memory, perception and our internal compass. Kemp tells us – unsurprisingly – that this navigational task is one of the most ‘cognitively complex’ that our brains perform.
But don’t be alarmed if all of this is starting to sound confusing. Kemp effectively hacks through the thickets and briars, and keeps us on the right path. He’s good at both explaining and minimising the technical jargon. He’s also able to outline difficult concepts clearly, without condescending or over simplifying.
Better still, Kemp is decent company. Dark and Magical Places is as entertaining as it is enlightening. Kemp is consistently amusing when it comes to his own personal navigational deficiencies and tells some gripping and heart-rending stories about other people who’ve wandered from the trail, become lost and never made it back.
He also stands up for those of us who are more prone to getting hopelessly lost. He shows not only how easy it is to become disorientated, but also that there are good reasons some people are worse navigators. Not everyone can construct a cognitive map. It isn’t just a question of paying attention or being careful – there are real physical and cognitive differences between individuals.
These differentials in navigational ability provide a further vein of interest. The popular belief that men are better at navigating than women gets a particularly useful workout. Kemp shows that while some experiments have shown differences between the sexes, they aren’t there because of innate male navigational superiority. The variations are a function of inequality rather than inability. In Scandinavian countries, women test as well as men at navigation, whereas in less-equal societies, such as Saudi Arabia, where women have been banned from driving, they don’t. It’s also salutary that wealth per capita can also have an impact on navigational abilities. It turns out to be an issue of access, privilege and – if Scandinavian countries are anything to go by – a fondness for orienteering.
I was equally intrigued to read about the ability of the Sahara Desert ant to find the most direct route home by using dead-reckoning calculations based on the number of footsteps they’ve taken away from the nest. If you lift one up and move it slightly backwards, it won’t make it home. (Scientists have also generated the same result by taking scissors to the poor creatures and shortening some of their legs.)
I will also never again find it quite as easy to take for granted the fact that I tend to leave rooms through the correct exit rather than trying to climb through, say, a wardrobe door. Such spatial processing may be subliminal work, but Kemp shows that it’s worth paying it serious attention. It turns out that exploring the brain can be as rewarding as finding your way around the rest of the world.