The term sense of direction is made up of a lot of different components. If you've got a good sense of direction — as men are often rumored to — you never get lost or turned around in a foreign place, can remember exactly where you are in relation to other stuff, know the correct direction to walk in a confusing environment, and can always retrace your steps — and it often seems you can do it without trying at all. Well, you can stop congratulating yourself on being a superior human being, because it's all in your head. Literally.
Sense of direction might not seem like a big deal, but discovering one way in which the brain orients itself actually netted a British scientist and two of his Norwegian colleagues the 2014 Nobel Prize for Medicine. Their discovery focused on our memory of place (I'll get to what that means in a minute), but it's only part of the story. How we avoid getting grossly lost involves a bunch of different brain activities, including knowing our position relative to where we started, what direction we're currently headed in, and mapping what we already know of our environment in the brain. And new discoveries are pinning down just what bits of the brain are responsible for what.
This matters for a bunch of reasons. One is that sense of direction erodes a lot with Alzheimer's disease, and pinpointing the brain region that does the directing might help earlier diagnosis. Another is that direction has been very important in human evolution; we wouldn't have survived being nomads or roaming across the prairie if we didn't know where the hell we were. So here's why you can't find your way out of a shopping mall: It's all in your brain cells.
Always Getting Lost? Blame Your Entorhinal Cortex
The big discovery about sense of direction came in 2014, when a study by the University Of London pinpointed the exact part of the brain that does a crucial bit of internal navigation. It figures out not only what way you're currently facing, but what direction you should be facing in order to reach a goal. If you're facing a wall and need to turn left to get to the closest bookstore, the entorhinal cortex is what tells you to do it.
The study was actually pretty cool. They did fMRI scans of 16 participants' brains as they navigated around a simple virtual courtyard (which, frankly, looked like a bad image from an early Sims game). They then watched what happened when subjects were asked to think about heading toward different objects in the courtyard — plan a navigation, in other words. And hey, presto: The entorhinal cortex glowed bright as day.
Is A Sense Of Direction Linked To Good Memory?
If you think having a good sense of direction involves having an awesome memory, you're right: Research showed that we have "place cells" in our hippocampus, the seat of memory, that map out any new environment and embed it in our memory. It also showed that we have another type, "grid cells," which live inside the entorhinal cortex, and provide a kind of 3-D map of where you are in relation to your environment.
Turns out we also have things called "head-direction" cells. They do what the name suggests — they tell us what direction we're currently facing, like a compass. But obviously a sense of navigation is useless unless you know where you currently are, so these cells are seriously important to the whole shebang.
Here's the kicker: The weaker the signals in your entorhinal cortex, the less likely you are to be able to find your way out of a paper bag. If you get lost, it's likely the signals just aren't keeping up.
How Men And Women Navigate Differently
There's a longstanding psychological tendency to believe that men have a better sense of direction than women — but we're still not sure if this is innate, or because of something else entirely. A really interesting study in 1994 showed that the problem might actually come down to self-confidence. Women were more likely to use a "route strategy" and follow instructions or a map, while men were more likely to rely on their own orientation (in other words, their hippocampus and entorhinal cortex) to do the work.
This doesn't mean that men's entorhinal cortexes have stronger signals; instead, it shows that women were less likely to trust their own navigational impulses. (The study also showed that women had higher "spatial anxiety," or fear of getting lost). So the gender difference may actually come down to a lack of self-belief in our own directional capacity.
However, that may not be the end of the story: A study by the University of Utah in 2014 has found that men with better direction in two African tribes were more successful with the ladies — so the idea of male navigational superiority might actually have been an evolutionary development, to help dudes get laid. And a 2010 study of how rat pups acquire their sense of direction raised the possibility that any disadvantage might actually come from how women and men accumulate and store navigational information throughout their lives.
Long story short? The jury's still sort of out on whether men are better navigators and why. But have faith in your own entorhinal cortex — the signals may not lead you astray.
Side Note: There's A Magnetic Compass Inside Your Nose
There's a weirder theory you should know about our sense of direction, though, and it has to do with a tiny mineral embedded in our noses. Yes, really. Nasal cells in trout, who navigate huge distances for migration, were studied in 2012, and it was found that they contain a concentration of magnetite, a magnetic mineral that lets them pick up on magnetic fields. That's the secret to how one navigates around the globe: We're directed by magnetic noses.
These "magnoreceptors" explain a lot — like how the hell navigating animals of many species manage to get themselves around the world year after year, often to the exact same places. And it looks like there are remnants of this same propensity in humans — but there's a big catch. The ethmoid bone in the nose appears to contain a very small amount of magnetic material, but it is currently believed not to have much of a role in direction at all — at least that we know about. Instead, it's probably left over from an earlier evolutionary strategy we don't use anymore.
The idea that magnetic fields might actually affect human navigation isn't a new one, but it hasn't accumulated a lot of scientific proof. A study in 2011 found that a protein in the human retina could actually "see" magnetic fields — but that it only works in the blue range of light, rendering it effectively useless. At the moment, it seems we used to use magnetic fields to help us navigate, but that our brains took over the job.
So remember: The next time you rely on your GPS for a trip to grocery store, you can just casually tell your friends that your hippocampus and entorhinal cortex aren't cooperating.