Rapha Mondial: Let's Get Lost

Ever since the earliest creatures swam in the primordial sea or lurched across the land, animals have needed to know where they’re going – whether headed for food, shelter, safety or sex. Our ancestors migrated thousands of miles across the face of the planet in search of new homes. Then, once they’d established their settlements, they needed to make sure they could get back to them.

Humans have traditionally relied on heaven and earth for guidance, taking bearings from the sun and stars or familiar landmarks. We made ever more detailed maps, marking out the world in precise quadrants and recreating reality with symbols and signs. Today, navigation is the domain of digital devices. The Global Positioning System (GPS), which uses satellites for location tracking, was originally invented by the US military in the 1970s. Combined with satellite navigation (satnav) devices and mobile phone apps, it has quickly become a vital tool for civilians everywhere.

But there’s much more to wayfinding than these external maps. Our most important navigation system is embedded deep within the brain, according to Hugo Spiers from University College London. We meet in his office in Bloomsbury, with large windows showcasing an impressive view of north London on one side and plastered with a large map of the city on the other.

“There is a dedicated system that can be linked to the idea of a compass and a map,” he explains. “You have cells in your brain called grid cells, which help you to construct a kind of map of the world. Right now you’re sitting in my office, which you’ve not been in before, but you were using those cells as you were walking down the corridor coming here – they provide a calculation of how far you’ve walked.”

These curious, calculating cells are the discovery of Norwegian husband-and-wife team Edvard and May-Britt Moser, who won a Nobel prize in 2014 for their work. As far back as 1971, scientists working with rats had noticed that certain nerve cells in part of the brain called the hippocampus – a region commonly associated with memory – fired if an animal was in a specific place. These special cells (simply known as place cells) were thought to be the home of our internal navigation, but the Mosers realised that this wasn’t the whole story.

After tracking the complex web of nerve connections between the hippocampus and another region called the entorhinal cortex, they discovered another set of cells that also activated when a rat moved into a particular location. This time, the cells fired in a surprisingly regular hexagonal pattern, effectively creating a grid system inside the brain.

Although much of their research has been done using animals, especially rats, the results still hold up in humans: as we move around the world, our grid cells are firing up in a regular pattern, helping us to keep track of where we’ve been and where we are now. This grid isn’t as neat as the lines of latitude and longitude on a map, but together with the hippocampal place cells they form the fundamental components of our internal satnav.

“Grid cells fire as you move around, and place cells tell other bits of the brain ‘you are here’,” says Spiers. “They’re part of the memory system, providing a really robust signal of where you are in the world and all the aspects that you want to know about it: is this a good or bad place? Do you get food here? What are your memories of this place?”

As well as grid and place cells there are also boundary cells, which fire when we encounter a physical limit such as a wall or junction, and speed cells that monitor how fast we’re travelling. We also have a sense of which way we’re facing and we know which way is up. And most of us use visual information such as landmarks and the sun to orient ourselves and figure out where we’re going, although visually impaired people must rely more on their other senses and internal maps for navigation. But, as Spiers points out, studying the firing patterns of individual brain cells in rats can’t tell us how humans find our way in the world.

“Say I want to go to a coffee shop. I might have a memory of that coffee shop, and those place cells in my hippocampus will be active when I reach it. My grid cells can tell me where I am now, but there’s no ‘coffee shop cell’ that tells me where it is. What I want to know is how we construct maps in the brain to get where we want to go and learn how the whole guidance system works together.”

To find out, he’s using a type of scanning technique known as functional magnetic resonance imaging (fMRI), which measures the activity levels throughout the brain. The scanners are impressive bits of kit – huge electronic doughnuts that sound like a broken washing machine – but their hefty size is problematic when it comes to studying navigation. Spiers and his team are working on a portable version that could be worn like a helmet, but in the meantime they’ve had to find creative ways to mimic the experience of navigation within the confines of their equipment.

Rather than use virtual reality to create a pretend world, Spiers sent a film crew out into the streets of Soho to capture the experience of navigating the warren of the West End. The footage was then turned into a kind of choose-your-own-adventure movie and used to train volunteers. Using the film simulation, Spiers gets people to ‘walk’ around Soho and learn the streets. Then the next day they take a trip to the fMRI scanner for a test of their navigation skills, watching film clips and deciding which way to turn to reach a particular destination.

By putting people in this high-pressure situation, made even more challenging because they can win money by getting directions correct and lose cash for every wrong turn, Spiers and his team can gather unique insights into the regions of the brain that are active when someone is trying to navigate. Unsurprisingly the hippocampus is centre stage, along with part of the brain known as the prefrontal cortex, which is responsible for planning and decision-making.

The results support the idea of a kind of conversation between the two parts of the brain, with the hippocampus throwing up possible route ideas and the prefrontal cortex choosing the option that’s most likely to get us to our desired destination. Junctions with many exits – such as the eponymous Seven Dials – triggered more brain activity, while dead-ends damped it down. This also fits with previous results from UCL scientists, showing that the hippocampus expands in taxi drivers who have undertaken the gruelling Knowledge test of London’s streets.

However, this neural conversation falls silent when Spiers adds a satnav into the mix. Instead of asking volunteers to choose what they think is the right direction when faced with a junction, an instruction is flashed up telling them which way to go. Without the need to plan and decide the next move, the hippocampus effectively switches off and lets the satnav take the strain instead. But could the pervasiveness of this technology be dumbing down our internal navigation systems and causing long-term cognitive problems?

“It’s a valid question,” muses Spiers, “and the answer is only as good as the evidence we have. Right now there’s no research that really addresses the issue, so you’re in the realm of speculation as to whether it’s bad for you to be using a satnav. But what our research is showing us is that you’re effectively activating your brain in certain ways when you’re actively navigating that you’re not doing when you use a satnav. Whether that’s good or bad we don’t know, but if you use the muscles in your body it’s good for your health so it seems quite likely that it’s the same for the brain.”

Even the most street-savvy among us has become lost or disoriented at some point in an unfamiliar city. Or perhaps you’ll know the misery of setting out for a short ride and coming back hours later, wet and hungry after a few too many wrong turns. In these situations, the temptation is just to reach for a smartphone or satnav to get back on the right track. But if Spiers’ results suggest we should be cautious about over-reliance on electronic devices to tell us where we’re going, other researchers are investigating how to make wayfinding more intuitive and less taxing without relying on satnavs to guide our every move. And, according to Thora Tenbrink, a reader in cognitive linguistics at Bangor University, that involves making navigation tools behave more like humans do when we’re giving each other directions.

It’s hard to get lost if you’re with someone who knows where they’re going, Tenbrink tells me, and there are wayfinding tools that mimic that experience. We’re speaking in a bustling London hotel where she’s hosting a conference focusing on cognitive science, so by way of example she highlights the bright purple and orange footprints plastered across the lobby floor leading delegates to the right meeting room. But in the absence of a trusted navigator or clear signposts, we might have to rely on asking someone for directions – and it’s here that the problems start. It would be weird if a human started to give precise turn-by-turn directions and distances exactly like a satnav but our attempts to give accurate route information can create rather than clear up confusion.

“If you have to ask someone for directions, they can give you too much information and you glaze over, because you don’t have the same understanding of the area that they do,” Tenbrink says. “You just have to memorise every single turn, and we know from research and language comprehension that’s just not what we do. Also the directions might not be accurate – that happens all the time!”

Rather than giving detailed (and probably wrong) instructions, Tenbrink’s work shows that one of the most useful things to do is point someone broadly in the right direction and let them figure it out.

“We’ve known for a long time that people simplify directions, they don’t have all the details in their minds,” Tenbrink explains. “The biggest simplification that we can make is to think ‘it’s over there’, and follow the arrow in our minds. We know roughly how far it is away and in which direction, and it doesn’t get any simpler than that.”

Based on this knowledge, she’s been working with the developers of Beeline – a new navigation device aimed at cyclists that acts in the same way as this helpful human. Once a user has strapped the device to their handlebars and set a location through the linked phone app, the Beeline acts more like a compass than a satnav simply giving a general direction and distance from the target. It’s then up to the user to figure out the best route from A to B from the roads in front of them, engaging their hippocampus and prefrontal cortex rather than relying on turn-by-turn directions.

As well as building more intuitive navigation devices, there are tricks that architects and city planners can steal from neuroscience to make it easier for people to get around. Hugo Spiers has even gone as far as setting up a new company, The Centric Lab, to take his research findings to the streets.

“There are hundreds of buildings and spaces out there that are badly designed, and we’re trying to draw on the latest neuroscience, psychology and cognitive science to make them better,” he says. “We can use our neuroscientific tools to measure things with more precision than developers currently do.”

As well as using brain scanners and head-mounted cameras to see how people respond to real-world navigation challenges, he and his team are using the latest immersive virtual and augmented reality technology to experiment in the virtual universe.

“Say you’re developing a new cycle route: we could create an immersive virtual system to ask what would it feel and look like, and let people try it out. That will allow planners to go ahead more confidently knowing that it’s going to work. We might get more people cycling if we can make it more intuitive to navigate on a bike.”

There’s more to this idea than simply boosting our ability to get around without constantly relying on maps and devices. Given that problems with wayfinding are one of the early signs of dementia – often characterised by wandering or failing to remember the way home – improving navigability in urban areas is becoming increasingly important for an ageing population. And while there’s no evidence at the moment that keeping the navigation centre of the brain working hard can stave off dementia, it certainly won’t hurt.

“The other thing that’s important is empowerment,” says Spiers. “If you put away the devices and learn how to navigate, you are empowered and don’t have to worry about the technology. You’re more embedded in your environment, you’re getting more from it and it may be better for you. It’s a challenge to make this technology work, but I think better navigation systems could make things more fun. A satnav will definitely get you there, but at the moment it’s not fun.”