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Do People Really Walk in Circles When They’re Lost?

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It’s a reliable movie trope: Our heroes are lost in the woods, and in their valiant effort to make a beeline out of the forest or back to camp or civilization, they inevitably get turned around and wind up back at the same spot where they began.

When a science television show approached Jan Souman, a research scientist at the Max Planck Institute for Biological Cybernetics, with a viewer’s question about the phenomenon, Souman wasn't sure if people actually did accidentally circle back. When lost, he thought, people would probably veer left or right randomly, but not actually circle back.

To find out, he and his research group gathered nine volunteers and stuck six of them in a German forest and the other three in the Tunisian desert. All of them were instructed to walk as straight as possible in one direction for several hours while wearing GPS receivers so that the researchers could analyze their routes.

Course Correction

Souman found that all of them eventually veered off course, and more than half did end up circling back to cross their own paths without realizing it. There was an interesting twist, though. The circling only happened with the four of the forest walkers who made their journeys in overcast conditions and the one desert walker who walked on a night with no visible moon. Those who could see the sun or moon managed to travel in straighter lines and, when they did lose their way, moved as Souman had predicted, veering left and right while generally going in the same direction and not crossing back on their route.

In a second experiment, the researchers had 15 volunteers try to walk in a straight line for an hour while blindfolded. When they couldn't see at all, the walkers circled back sooner, more often, and in tighter arcs, sometimes making a circle about the size of a basketball court.

The two experiments cast doubt on an older idea that this kind of disorientation comes from biomechanical asymmetries—like a differences in length or strength between the left and right legs—that create small but consistent directional bias. That would cause a person to consistently veer off in the same direction, especially when the person is blindfolded and without visual cues to compete with the bias. But only three of the walkers had a tendency to veer in one direction, while the others varied wildly in their circling, with their paths looking like a child had scribbled on a piece of paper. Walking in circles, Souman and his team think, isn’t caused by some physical bias, but an uncertainty about where straight ahead lies that increases over time.

Visual Clues

For the walkers in the first experiment, visual cues appeared to be very important. Those who could see some external reference point—the sun, the moon, a hill in the far distance—could use it to recalibrate their sense of direction and maintain a relatively straight path. (Interestingly, Souman notes that the volunteers in the first experiment walked for several hours, during which the sun moved about 50 to 60 degrees; rather than following a correspondingly bent path, they were able to correct for this, even if subconsciously.)

The volunteers who walked when it was cloudy or dark or while they were blindfolded didn’t have this luxury and walked in circles. Without a reference point to maintain their course, these subjects had to rely on other cues, like sounds and information from the vestibular system, which aids in movement, balance and spatial orientation. Small random mistakes in the processing of these cues, Souman and team think, add up over time, especially when the senses are limited. Eventually, the internal compass fails and “random changes in the subjective sense of straight ahead” lead a person off the straight and narrow path and right back where they started from.

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Big Questions
What Is the Difference Between Generic and Name Brand Ibuprofen?
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What is the difference between generic ibuprofen vs. name brands?

Yali Friedman:

I just published a paper that answers this question: Are Generic Drugs Less Safe than their Branded Equivalents?

Here’s the tl;dr version:

Generic drugs are versions of drugs made by companies other than the company which originally developed the drug.

To gain FDA approval, a generic drug must:

  • Contain the same active ingredients as the innovator drug (inactive ingredients may vary)
  • Be identical in strength, dosage form, and route of administration
  • Have the same use indications
  • Be bioequivalent
  • Meet the same batch requirements for identity, strength, purity, and quality
  • Be manufactured under the same strict standards of FDA's good manufacturing practice regulations required for innovator products

I hope you found this answer useful. Feel free to reach out at www.thinkbiotech.com. For more on generic drugs, you can see our resources and whitepapers at Pharmaceutical strategic guidance and whitepapers

This post originally appeared on Quora. Click here to view.

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Big Questions
Do Cats Fart?
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Certain philosophical questions can invade even the most disciplined of minds. Do aliens exist? Can a soul ever be measured? Do cats fart?

While the latter may not have weighed heavily on some of history’s great brains, it’s certainly no less deserving of an answer. And in contrast to existential queries, there’s a pretty definitive response: Yes, they do. We just don’t really hear it.

According to veterinarians who have realized their job sometimes involves answering inane questions about animals passing gas, cats have all the biological hardware necessary for a fart: a gastrointestinal system and an anus. When excess air builds up as a result of gulping breaths or gut bacteria, a pungent cloud will be released from their rear ends. Smell a kitten’s butt sometime and you’ll walk away convinced that cats fart.

The discretion, or lack of audible farts, is probably due to the fact that cats don’t gulp their food like dogs do, leading to less air accumulating in their digestive tract.

So, yes, cats do fart. But they do it with the same grace and stealth they use to approach everything else. Think about that the next time you blame the dog.

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

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