Scientists Created "Ghosts" in the Lab

istock collage
istock collage

Have you ever experienced the creepy sensation that you’re not the only person in the room? You get a chill, maybe the hair on the back of your neck stands up, and for a second you think maybe you do believe in ghosts. 

This sensation is commonly reported in people with certain neurological or psychiatric disorders, or those exposed to extreme conditions. In 1970, mountaineer Reinhold Messner reported seeing a “phantom” climber descending the slopes of a particularly extreme summit alongside him. This also happens in people who have recently experienced another extreme condition: the loss of a spouse. In most cases, the sufferer reports the very real sensation of an unseen presence. This is the stuff of which ghost stories are made, but researchers say they know why this feeling occurs, and they’ve even recreated it in the lab. 

Olaf Blanke, a researcher from the Swiss Federal Institute of Technology in Lausanne, Switzerland (EPFL), first had to find the scientific culprit for these strange sensations. He and his team analyzed brain scans of patients suffering from neurological disorders who experience the ghostly feeling. They found abnormalities in the areas controlling how the brain sees the body, or one’s own spatial self-awareness. These abnormalities “can sometimes create a second representation of one’s own body, which is no longer perceived as ‘me’ but as someone else, a ‘presence,’” says Giulio Rognini, who led the study. 

Armed with an understanding of where the feeling of being haunted comes from, the researchers set out to recreate it in “healthy” people. A group of subjects—oblivious as to the experiment’s purpose—were blindfolded, their fingers connected to a robotic device. When the test subjects moved the device, a robotic arm behind them mimicked the movement, poking them in the back. Sounds pretty straightforward, but when researchers introduced a slight delay between the subject’s movement and the resulting poke, the subjects were spooked. They felt they were being touched by another presence. Some even reported sensing more than one “ghost.” 

“Actually some subjects reacted very strongly and they reported not only that they felt that somebody else was touching them but that somebody else was also present,” Blanke says. For some people the sensation was so strong, they didn’t want to finish the experiment. 

“This confirms [the sensation] is caused by an altered perception of their own bodies in the brain,” Blanke says. So the next time you feel like you’re being watched, remember it might just be your brain playing tricks on your perception.

Aside from disappointing ghost hunters, this research could someday help treat disorders like schizophrenia or other neurological and psychiatric conditions. 

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What Really Happens When Food Goes Down the 'Wrong Pipe'?

The dreaded 'wrong pipe' calamity can strike at any time.
The dreaded 'wrong pipe' calamity can strike at any time.
Photo by Adrienn from Pexels

Your average person isn’t expected to be well-versed in the linguistics of human anatomy, which is how we wind up with guns for biceps and noggins for heads. So when swallowing something is followed by throat irritation or coughing, the fleeting bit of discomfort is often described as food “going down the wrong pipe.” But what’s actually happening?

When food is consumed, HuffPost reports, more than 30 muscles activate to facilitate chewing and swallowing. When the food is ready to leave your tongue and head down to your stomach, it’s poised near the ends of two "pipes," the esophagus and the trachea. You want the food to take the esophageal route, which leads to the stomach. Your body knows this, which is why the voice box and epiglottis shift to close off the trachea, the “wrong pipe” of ingestion.

Since we don’t typically hold our breath when we eat, food can occasionally take a wrong turn into the trachea, an unpleasant scenario known as aspiration, which triggers an adrenaline response and provokes coughing and discomfort. Dislodging the food usually eases the sensation, but if it’s enough to become stuck, you have an obstructed airway and can now be officially said to be choking.

The “wrong pipe” can also be a result of eating while tired or otherwise distracted or the result of a mechanical problem owing to illness or injury.

You might also notice that this happens more often with liquids. A sip of water may provoke a coughing attack. That’s because liquids move much more quickly, giving the body less time to react.

In extreme cases, food or liquids headed in the “wrong” direction can wind up in the lungs and cause pneumonia. Fortunately, that’s uncommon, and coughing tends to get the food moving back into the esophagus.

The best way to minimize the chances of getting food stuck is to avoid talking with your mouth full—yes, your parents were right—and thoroughly chew sensible portions.

If you experience repeated bouts of aspiration, it’s possible an underlying swallowing disorder or neurological problem is to blame. An X-ray or other tests can help diagnose the issue.

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