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Is Your Sense of Direction Innate?

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ThinkStock

Some people are like homing pigeons: Drop them off anywhere, and they’ll find their way around. Other people, though, can’t tell when they’re holding a map upside down. Are the directionally challenged just bad learners? Or are some of us just lucky to be born with a strong internal compass?

Not all of your navigational skills are learned. There’s evidence that your sense of direction is innate. (Some of it, at least.) Your brain is packaged with special navigational neurons—head-direction cells, place cells, and grid cells—and they help program your internal GPS when you’re just a wee tot.  

In 2010, two different studies (here and here) explored whether rats were born with a sense of direction. Scientists implanted electrodes in the brains of baby rodents and tracked their neural activity. Although the rats were newborns, the researchers discovered that their head-direction cells (which help us recognize the direction we’re facing) were fully mature. The rats, it seemed, were born with an intrinsic sense of direction. And they hadn’t even opened their eyes yet!

Humans, of course, are not rats. But the hippocampus—the brain region responsible for navigation and spatial memory—is similar in most mammals. If the rat’s internal compass develops this way, then it’s likely that a human’s compass does, too.

Off the Grid

If we’re born with a sense of direction, then why are some people so good at getting lost? The scientists found that the two other cells—place and grid cells—developed within the first month. Place cells are thought to help us form a mental map, while grid cells help us navigate new and unfamiliar places. The two cells interact—and that’s where the trouble might be.

In a 2013 study from Nature, participants played a video game that required them to shuttle back and forth between virtual locations. Monitoring their brains, the scientists found that grid cells helped the gamers keep track of their whereabouts—even without landmarks. According to researcher Michael Kahana and the Daily Mail, it’s a “reasonable assumption that differences in how grid cells work explain why some people have a better sense of direction than others.”

So rejoice, navigationally challenged people! If you’ve ever gotten lost pulling out of your driveway, your may now blame your grid cells.

Of course, the nature-nurture argument isn’t black and white here. Although this neural network is hardwired from the time you’re born, it matures thanks to your interactions with the world. These connections are like the prefab wiring in your house, while your experiences with the environment are like the solder that makes that wiring stronger. Both help.  

Will a GPS mess with this wiring?

A GPS may save your behind now and then, but it may meddle with your navigational skills if you depend on it to get everywhere. We naturally get around by using a process called “dead reckoning.” Basically, you estimate where you are by comparing your location to a reference point. You use a mental map to make these estimates. Problem is, when you rely on a GPS, that mental map can get foggy.

A 2005 study at the University of Nottingham asked people to drive to a specific spot. Some of them were given step-by-step directions, while others were handed an old-fashioned map. At the end of their journey, they were asked to sketch out the route they traveled. The folks who were given instructions drew the most inaccurate maps. People who used a GPS to walk around a city faced the same problem.

Two things are to blame. First, when you depend on a GPS, you’re more likely to ignore your surroundings. You don’t memorize as many landmarks because you don’t need to. As a result, your mental map is less detailed. That’s why people who depend on a GPS sometimes panic during detours. By updating the map on their GPS, they fail to update the map in their brain.

The second reason isn’t as earth shattering. A GPS usually prevents you from huge blunders (disclaimer: OK, sometimes not). People who navigate on their own are more likely to screw up. Thankfully, the experience of committing a gaffe actually improves their mental map. Making mistakes remains one of the best ways to learn. 

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What Happens When You Flush an Airplane Toilet?
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For millions of people, summer means an opportunity to hop on a plane and experience new and exciting sights, cultures, and food. It also means getting packed into a giant commercial aircraft and then wondering if you can make it to your next layover without submitting to the anxiety of using the onboard bathroom.

Roughly the size of an apartment pantry, these narrow facilities barely accommodate your outstretched knees; turbulence can make expelling waste a harrowing nightmare. Once you’ve successfully managed to complete the task and flush, what happens next?

Unlike our home toilets, planes can’t rely on water tanks to create passive suction to draw waste from the bowl. In addition to the expense of hauling hundreds of gallons of water, it’s impractical to leave standing water in an environment that shakes its contents like a snow globe. Originally, planes used an electronic pump system that moved waste along with a deodorizing liquid called Anotec. That method worked, but carrying the Anotec was undesirable for the same reasons as storing water: It raised fuel costs and added weight to the aircraft that could have been allocated for passengers. (Not surprisingly, airlines prefer to transport paying customers over blobs of poop.)

Beginning in the 1980s, planes used a pneumatic vacuum to suck liquids and solids down and away from the fixture. Once you hit the flush button, a valve at the bottom of the toilet opens, allowing the vacuum to siphon the contents out. (A nonstick coating similar to Teflon reduces the odds of any residue.) It travels to a storage tank near the back of the plane at high speeds, ready for ground crews to drain it once the airplane lands. The tank is then flushed out using a disinfectant.

If you’re also curious about timing your bathroom visit to avoid people waiting in line while you void, flight attendants say the best time to go is right after the captain turns off the seat belt sign and before drink service begins.

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Why is Friday the 13th Considered Unlucky?
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Today, people around the globe will feel uneasy about getting out of bed, leaving their homes, or going about their normal daily routines, all because of a superstition. These unfortunate folks suffer from paraskavedekatriaphobia, a common neurosis familiar to us all: the fear of Friday the 13th. But just where did this superstitious association come from, and how did it catch on?

The truth is that no one is absolutely sure where the idea that Friday the 13th is unlucky originated. Donald Dossey, the founder of the Stress Management Center and Phobia Institute in Asheville, North Carolina, suspects the fear can be traced back to a Norse myth about 12 gods who had a dinner at Valhalla—the fabled hall where legendary Norse heroes feasted for eternity after they died—that was interrupted by a 13th guest, the evil and mischievous god Loki.

According to legend, Loki tricked Höðr (the blind god of winter and son of Odin, the supreme god in Norse mythology) into shooting his brother Baldr (the benevolent god of summer who was also a son of Odin) with a magical spear tipped with mistletoe—the only substance that could defeat him. Thus the number 13 was branded as unlucky because of the ominous period of mourning following the loss of such powerful gods by this unwanted 13th guest.

For whatever reason, among many cultures, the number 12 emerged throughout history as a "complete" number: There are 12 months in a year, 12 signs of the zodiac, 12 Gods of Olympus, 12 sons of Odin, 12 labors of Hercules, 12 Jyotirlingas or Hindu shrines where Shiva is worshipped, 12 successors of Muhammad in Shia Islam, and 12 tribes of Israel. In Christianity, Jesus was betrayed by one of his 12 Apostles—Judas—who was the 13th guest to arrive for the Last Supper. Surpassing the number 12 ostensibly unbalances the ideal nature of things; because it is seen as irregular and disrespectful of a sense of perfection, the number 13 bears the stigma of misfortune and bad luck we know today.

WHY FRIDAY?

Friday joins in the mix mostly because all of the early accounts of Jesus’s crucifixion agree that it took place on Friday—the standard day for crucifixions in Rome. As Chaucer noted in The Canterbury Tales, "And on a Friday fell all this mischance." Yet perpetuating Friday as an unlucky day in America came from the late 19th-century American tradition of holding all executions on Fridays; Friday the 13th became the unluckiest of days simply because it combined two distinct superstitions into one. According to the Oxford University Press Dictionary of Superstitions, the first reference to Friday the 13th itself wasn’t until 1913. (So despite actually occurring on Friday, October 13, 1307, the popular notion that the Friday the 13th stigma comes from the date on which the famed order of the Knights Templar were wiped out by King Philip of France is just a coincidence.)

The repercussions of these phobias reverberated through American culture, particularly in the 20th century. Most skyscrapers and hotels lack a 13th floor, which specifically comes from the tendency in the early 1900s for buildings in New York City to omit the unlucky number (though the Empire State Building has a 13th floor). Some street addresses also skip from 12 to 14, while airports may skip the 13th gate. Allegedly, the popular Friday the 13th films were so-named just to cash in on this menacing date recognition, not because the filmmakers actually believed the date to be unlucky.

So, is Friday the 13th actually unlucky? Despite centuries of superstitious behavior, it largely seems like psychological mumbo jumbo. One 1993 study seemed to reveal that, statistically speaking, Friday the 13th is unlucky, but the study's authors told LiveScience that though the data was accurate, "the paper was just a bit of fun and not to be taken seriously." Other studies have shown no correlation between things like increased accidents or injuries and Friday the 13th.

And Friday the 13th isn't a big deal in other cultures, which have their own unlucky days: Greeks and Spanish-speaking countries consider Tuesday the 13th to be the unluckiest day, while Italians steer clear of Friday the 17th. So today, try to rest a little easy—Friday the 13th may not be so unlucky after all.

Additional Source: 13: The Story of the World’s Most Popular Superstition.

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