CLOSE
Original image
ThinkStock

Is Your Sense of Direction Innate?

Original image
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. 

Original image
iStock
arrow
Big Questions
Why Is Soda Measured in Liters?
Original image
iStock

Never a nation to fall in line, America is one of the few countries to resist the metric system. We stubbornly measure distance in miles and weight in pounds. So what’s with those two-liter bottles of soda?

First, a clarification: Soda is far from the only substance we measure in metric units. Heck, it’s not even the only beverage. Wine, liquor, and bottled water are sold by the milliliter. The healthcare field is all about metric units, too, from cholesterol levels to prescription, over-the-counter, and supplement dosages. We run 5-kilometer races, ride on 215-millimeter tires, and use 8-millimeter cameras, or at least we used to.

In most other things, we determinedly cling to our imperial measurements. Attempts to convince Americans to join the rest of the metric-measuring world have been met with great resistance.

Ken Butcher of the National Institute of Science and Technology has been working with the government’s tiny Metric Program for years. Speaking to Mental Floss back in 2013, Butcher explained that we’re so entrenched in our way of doing things that switching measurement systems now would be both chaotic and expensive.

"If we were going to start a new country all with the metric system, it would be easy," he said. "But when you have to go in and change almost everything that touches people’s everyday life and their physical and mental experience, their education, and then you take that away from them—it can be scary."

Here and there, though, when it’s convenient, we have been willing to budge. The soda bottle is a good example. Until 1970, all soft drinks in the U.S. were sold in fluid ounces and gallons, mostly in glass bottles. Then the plastic polyethylene terephthalate (PET) bottle came along, and soft drink makers decided it was time for a product redesign.

The redesign process coincided with two key factors: a short-lived wave of government interest in going metric, and the burgeoning environmental movement.

The folks at PepsiCo decided to meld all three into its exciting new vessel: a lightweight, cheap, recyclable, metric bottle, with built-in fins so it could stand up on supermarket shelves. Two liters: the soda size of the future.

The two-liter bottle took off. The rest of the soft drink world had no choice but to get on board. And voila: liters of cola for all.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

Original image
iStock
arrow
Big Questions
Where Is the Hottest Place on Earth?
Original image
iStock

The summer of 2017 will go down as an endurance test of sorts for the people of Phoenix, Arizona. The National Weather Service issued an extreme heat warning, and planes were grounded as a result of temperatures exceeding 120 degrees. (Heat affects air density, which in turn affects a plane’s lift.)

Despite those dire measures, Phoenix is not the hottest place on Earth. And it’s not even close.

That dubious honor was bestowed on the Lut Desert in Iran in 2005, when land temperatures were recorded at a staggering 159.3 degrees Fahrenheit. The remote area was off the grid—literally—for many years until satellites began to measure temperatures in areas that were either not well trafficked on foot or not measured with the proper instruments. Lut also measured record temperatures in 2004, 2006, 2007, and 2009.

Before satellites registered Lut as a contender, one of the hottest areas on Earth was thought to be El Azizia, Libya, where a 1922 measurement of 136 degrees stood as a record for decades. (Winds blowing from the nearby Sahara Desert contributed to the oppressive heat.)

While the World Meteorological Organization (WMO) acknowledged this reading as the hottest on record for years, they later declared that instrumentation problems and other concerns led to new doubts about the accuracy.

Naturally, declaring the hottest place on Earth might be about more than just a single isolated reading. If it’s consistency we’re after, then the appropriately-named Death Valley in California, where temperatures are consistently 90 degrees or above for roughly half the year and at least 100 degrees for 140 days annually, has to be a contender. A blistering temperature of 134 degrees was recorded there in 1913.

Both Death Valley and Libya were measured using air temperature readings, while Lut was taken from a land reading, making all three pretty valid contenders. These are not urban areas, and paving the hottest place on Earth with sidewalks would be a very, very bad idea. Temperatures as low as 95 degrees can cause blacktop and pavement to reach skin-scorching temperatures of 141 degrees.

There are always additional factors to consider beyond a temperature number, however. In 2015, Bandar Mahshahr in Iran recorded temperatures of 115 degrees but a heat index—what it feels like outside when accounting for significant humidity—of an astounding 163 degrees. That thought might be one of the few things able to cool Phoenix residents off.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios