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10 Scientists Who Experimented on Themselves

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getty images

Would you inject 50 hookworms under your skin for your job? Or steam in a vomit sauna for a few hours? Hopefully we non-scientists will never have to answer questions like these. But for the 11 brave souls on this list, experimenting on themselves was all in a day's work.

1. Jonas Salk

During his research at the University of Pittsburgh Medical School, Dr. Jonas Salk discovered a potential vaccine for polio. When they needed healthy human test subjects, Salk volunteered himself and his entire family for a vaccine trial. The filial gamble paid off. Everyone tested positive for anti-polio antibodies. He refused to patent the vaccine, and never received financial compensation for his discovery. (When Edward R. Murrow asked Salk who owned the patent on the vaccine, Salk responded with one of his most famous quotes: “Well, the people, I would say. There is no patent. Could you patent the sun?”)

2. David Pritchard

In 2004, after years of research in Papau New Guinea, immunologist-biologist David Pritchard wanted to test his findings, specifically that certain parasites can improve the immune system's defense against allergies, and possibly more serious autoimmune illnesses. Circumnavigating more years of red tape, Pritchard used himself as the first test subject, injecting 50 hookworms under his skin. He was able to deduce that only 10 hookworms were necessary for future test subjects.

3. John Paul Stapp

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Air Force officer and surgeon John Paul Stapp's self-experimentation earned him the nickname "the fastest man on earth." In his research, Stapp repeatedly strapped himself into a rocket sled, nicknamed the "Gee Whiz," and was propelled forward at speeds close to that of sound. He would then brake abruptly to determine the human body's ability to withstand abrupt deceleration. Many broken bones and a temporarily detached retina later, Stapp determined a human body can withstand 45 g of forward motion with an adequate harness.

4. August Bier

At the turn of the 20th century, August Bier discovered spinal anesthesia. His method involved injecting cocaine into the cerebrospinal fluid. To test its effectiveness Bier enlisted himself. During the experiment, a mix-up left Bier with a hole in his spine leaking cerebrospinal fluid. Bier's assistant stepped in. Once the assistant was properly numb, Bier kicked his shins, bludgeoned and burned him, plucked out his pubic hairs, and mashed his genitals. The assistant felt nothing – a success the two celebrated by drinking excessively that evening.

5. Werner Forssmann

Werner Forssmann (left), Getty Images

In 1929 in the basement of the Eberswaled Hospital in Germany, surgical resident Werner Forssmann inserted a ureteral catheter tube into his elbow, feeding it through a vein up to his heart. He used a mirror as his assistant, since he had restrained his nurse to the operating table. He then took an x-ray of his chest (at left) to determine the catheter had indeed made it to the right atrium. Instead of praise, Forssmann was met with condemnation. This rejection led him to abandon cardiology for urology, but he was later rewarded with the Nobel Prize in 1956.

6. Nathaniel Kleitman

In 1938, sleep researcher Nathaniel Kleitman and his assistant holed up in Mammoth Cave in Kentucky. They were attempting to manipulate their sleep cycles to adopt a 28-hour day. With constant temperature and no natural light, the conditions in the cave seemed perfect. After 32 days Kleitman's assistant had successfully adapted, but Kleitman failed. Nonetheless, the experiment's results helped to advance their study of circadian rhythms.

7. Sir Humphry Davy

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While at the Medical Pneumatic Institute of Bristol, Humphry Davy studied gases. Through a series of self-experiments with oxides of nitrous, Davy created what is known today as laughing gas. Though his initial attempts were meant to reproduce the pleasurable effects of opium and alcohol, Davy would ultimately recommend the use of nitrous oxide as an anesthetic. His recommendation would not be heeded until long after his death, but nitrous became an instant hit at fashionable parties.

8. Kevin Warwick

During the late 1990s, Kevin Warwick had his team surgically implant a silicon chip transponder into his forearm for an experiment known as Project Cyborg. Through this implant, Warwick's nervous system was monitored by a computer system. According to his website, the neural interface allowed him to "operate doors, lights, heaters and other computers without lifting a finger." In other words, the future is now.

9. Albert Hoffman

Swiss chemist Albert Hoffman was researching the fungus ergot for a pharmaceutical company when he discovered lysergic acid. His initial tests were inconclusive, but Hoffman decided to retest a synthesized version of the acid. In April of 1943, he ingested 25/1000 of a gram of a substance he called LSD-25 in his lab. Legend has it, on his bike ride home his eyes were opened up to a brave new hallucinogenic world. To this day, LSD enthusiasts observe April 19 as "Bicycle Day." Hoffman would continue to experiment with LSD until his death at 102.

10. Stubbins Ffirth

Stubbins Ffirth would have been a shoe-in for the world's wackiest name contest. Instead, he found his own unique path to historical notoriety. After witnessing the devastating 1793 Yellow Fever Epidemic, Ffirth hypothesized the viral hemorrhagic disease was not contagious. To prove his thesis, he tested the disease's characteristic black vomit. On himself. This included, but certainly was not limited to, pouring vomit into his open cuts or onto his eyeballs, drinking infected black vomit by the glassful, and stewing up to his waist in a veritable sauna of vomit. He would later rub blood and urine on his body as well, but ultimately avoided infection. In his 1804 book A Treatise on Malignant Fever; with an Attempt to Prove Its Non-Contagious Nature, he declared Yellow Fever not contagious. Turns out, Yellow Fever was contagious, but only through blood transmission via mosquito bite. Whoops.

15 Scientific Reasons Spring Is the Most Delightful Season

Summer, winter, and fall may have their fans, but spring is clearly the most lovable of the four seasons. Not convinced? Here are 15 scientific reasons why spring is great:


road and field on a sunny day

Spring marks the end of blistering winter and the transitional period to scorching summer. In many places, the season brings mild temperatures in the 60s and 70s. People tend to be most comfortable at temperatures of about 72°F, research shows, so the arrival of spring means you can finally ditch the heavy winter layers and still be comfortable.


sunny sky

Following the spring equinox, days begin lasting longer and nights get shorter. Daylight Saving Time, which moves the clock forward starting in March, gives you even more light hours to get things done. Those extra hours of sun can be a major mood-booster, according to some research. A 2016 study of students in counseling at Brigham Young University found that the longer the sun was up during the day, the less mental distress people experienced.


blue bird on branch

Many animals migrate south during the winter, then head north as temperatures rise. For relatively northern regions, there is no better indicator of spring than birds chirping outside your window. Their northward migration can start as early as mid-February and last into June, meaning that throughout the spring, you can expect to see a major avian influx. In addition to the satisfaction of marking species off your bird-watching checklist, seeing more of our feathered friends can make you happy. In 2017, a UK study found that the more birds people could see in their neighborhoods, the better their mental health.


Baby squirrels

Many animals reproduce in the spring, when temperatures are warmer and food is plentiful. Baby bunnies, ducklings, chipmunks, and other adorable animals abound come spring. Studies have found that seeing cute animals can have positive effects on humans. For instance, one small study in 2012 found that when college students looked at cute images of baby animals, they were better at focusing on a task in the lab. Being able to watch fluffy baby squirrels frolic outside your office window might make spring your most productive season of the year.


flowers hanging outside of a house

In 2015, a pair of public policy researchers discovered a hidden upside to "springing forward" for Daylight Saving Time. It reduced crime. When the sun set later in the evening, the study published in the Review of Economics and Statistics found, robbery rates fell. After Daylight Saving Time started in the spring, there was a 27 percent drop in robberies during that extra hour of evening sunlight, and a 7 percent drop over the course of the whole day.


child with rainbow umbrella jumping in puddle

Warmer temperatures mean you can spend more time outside without freezing your feet off, which is great for mental health. Across the seasons, research has found that taking walks in nature slows your heart rate and makes you more relaxed, but some research indicates that there is something special about spring's effect on your brain. A 2005 study from the University of Michigan linked spending 30 minutes or more outside in warm, sunny spring weather to higher mood and better memory. But the effect reverses when spring ends, since being outside in the warmest days of summer is usually pretty uncomfortable.


woman writing in a park

That same University of Michigan study found that spending time outside in the sunny spring weather isn't just a mood booster, it actually can change the way people think. The researchers found that being outdoors broadened participants' minds, leaving them more open to new information and creative thoughts.


leaves budding in spring

Spring brings green growth back to plants and trees. Depending on where you live, trees may begin sporting new leaves as early as mid-March. That successful spring leaf growth ensures a cool canopy to relax under during the hot summer—a hugely important factor in keeping cities comfortable. According to researchers, vegetation plays a big role in mitigating the urban heat island effect. When trees release water back into the air through evapotranspiration, it can cool down the areas around them by up to 9°F, according to the EPA.


tulip bulbs

It's amazing what a little sun can do for plants and grass. Through photosynthesis, plants convert sunlight, carbon dioxide, and water into food, releasing oxygen in the process. That means as plants start to grow in the spring, they pull carbon out of the atmosphere, providing an important environmental service. Plants take in roughly 25 percent of the carbon emissions humans produce, absorbing more than 100 gigatons of carbon through photosynthesis each growing season. Because of this, the amount of carbon dioxide in the atmosphere drops each spring and summer. (Unfortunately, it rises in the winter, when most plants aren't growing.)


wooden box full of fresh produce

Many vegetables and some fruits are harvested in the spring. 'Tis the season to get your local asparagus, greens, peas, rhubarb, and other fresh produce. Getting more fruits and vegetables into your diet isn't just good for the body; it's good for the soul. A 2016 study of more than 12,000 Australians found that when people increased the amount of fruits and vegetables in their diet, they felt happier and had higher rates of life satisfaction. If they increased their intake by eight portions a day (a tall order, we know) the psychological gains were equivalent to the change in well-being people experience when they go from being unemployed to having a job, the researchers found.


Flowers in a vase

After months spent conserving energy, flowers bloom in the spring, once they sense that the days have grown longer and the weather has turned warmer. That's good for humans, because several studies have shown that looking at flowers can make you happy. A 2008 study of hospital patients found that having flowers in the room made people feel more positive and reduced their pain and anxiety [PDF]. Another study from Rutgers University found that when participants were presented with a bouquet of flowers, it resulted in what scientists call a "true smile" a full 100 percent of the time. Seeing flowers had both "immediate and long-term effects" that resulted in elevated moods for days afterward, according to the researchers [PDF].


woman tying shoes in flower field

While it's important to keep moving no matter what the weather, research shows that working out can be more beneficial if you do it outside. A 2011 study found that, compared with an indoor workout, exercising outdoors in nature increased energy levels, made people feel revitalized, and decreased tension, among other positive effects. People who worked out in the fresh air also tended to say they enjoyed the experience more and would be likely to repeat it, suggesting that using nature as your gym might help you stick with your exercise regimen. While those benefits probably extend to winter, too, it's a whole lot easier to stomach the idea of a run once the weather warms up.


dew on grass and a daisy

Flu season in the U.S. typically lasts through the fall and winter, usually peaking between December and February and tapering off during the spring. The seasonal change is in part because of dry air. Cold temperatures mean a drop in humidity, and indoor heating only makes the air drier. This lack of moisture in the air can dry out your skin and the nasal cavities, leading to nose bleeds, irritated sinuses, and a greater risk of getting sick. Since the mucus in your nose is designed to trap viruses, when it dries up, you're more likely to catch something nasty, like the flu. As the weather warms up and becomes more humid throughout the spring, that mucus comes back. As the season wears on, not only can you lay off the body lotion, but you can probably put away the tissues—if you don't have spring allergies, that is.


windows open on a red house

Temperate weather makes it easier to get the fresh air you need. Opening your windows and allowing the breeze in serves as an important way to ventilate indoor spaces, according to the EPA. A lack of ventilation can lead to an unhealthy concentration of indoor pollutants from sources like cleaning product fumes, certain furniture and building materials, and stoves (especially gas ones), posing a threat to your health and comfort. Winter brings the highest rates of indoor pollutants like nitrogen oxide, a 2016 study of unventilated stove use in homes found. Spring brings the perfect opportunity to throw open those windows and doors and get the air moving again.


woman enjoying sitting in the sun

Sunlight triggers your body to produce the vitamin D, which keeps your bones strong. At northern latitudes, it's extremely difficult to get enough sun exposure naturally to maintain healthy vitamin D levels during the winter—even if you did want to expose your skin to the elements—but that starts to change during the spring. One Spanish study found that in Valencia (which shares a latitude with Philadelphia, Denver, Baltimore, Kansas City, and several other major U.S. cities), people only need 10 minutes outside with a quarter of their bodies exposed to the spring sunshine to get an adequate daily dose of vitamin D.

A version of this story originally ran in 2014.

8 Ways to Tell If Someone Is Lying to You

Sociopaths and narcissists may believe they have lying down to a science, but it turns out there are a lot of little clues that reveal even the most sophisticated level of mendacity. If you want to catch a liar in their tracks, look for the following "tells," courtesy of father and daughter Dan and Lisa Ribacoff, credibility assessment experts and advanced certified polygraph examiners based in New York. They use their skills in criminal investigations, business matters, family and relationship issues, and other areas; you might have seen them on TV. Dan is also a private investigator.

The Ribacoffs use a mix of psychology, body-language analysis, expert interview skills, and polygraph tests to determine whether someone is lying. A polygraph is a combination of medical devices that monitor any physiological changes, particularly heart rate, blood pressure, respiratory rate, and perspiration rate, that an interview subject undergoes during an interview. To begin this process, the examiner conducts a pretest interview, asking questions that should be easy for the subject to answer, such as name and age. This establishes a "baseline" of normal autonomic responses to benign questions. They may also do a "stimulation test" in which the subject is asked to lie consciously. Changes from the baseline may indicate deception—though that interpretation is up to the examiner.

The accuracy of polygraph tests has been questioned by numerous critics, including the American Psychological Association. Guilty people have passed them, and innocent people have failed them. But they're just one factor in the Ribacoffs' assessments, which are based mostly on reading people, not polygraphs.

Credibility assessment is not built upon a single tell but a combination, Dan tells Mental Floss: "There's not one verbal or non-verbal cue that is going to be the absolute indicator [of a lie]. It's a process of collecting pieces to the puzzle and putting that puzzle together."

Read on for tips to identify when someone might be lying to you.


A common habit for a person obfuscating the truth is to put physical distance between themselves and the person they're lying to, particularly if they're being questioned. "Sitting back and stretching your legs out is trying to gain distance between you and the interviewer," Dan says. Crossing one's arms, a defensive posture, is also a potential sign of duplicity.


Because lying activates the limbic system, whose goal is to keep you calm under stress, liars may have a hard time sitting still. "It's like the popcorn maker pops its lid [in your mind]," Dan says. "You do things to burn off nervous energy, like pick off imaginary lint, rub your arm—self-soothing behaviors such as moving or fidgeting." Lisa tells Mental Floss that "rubbing your neck or playing with hair" are also signs of potential deception, particularly if someone does it right after they lie to you.


man in suit avoids eye contact

Eye contact is intimate, vulnerable—and lots of liars can't hold a gaze when they're working up a mistruth. Lisa says she's found that examinees will often maintain eye contact "right up until they give the answer they're lying about." The polygraph usually reveals physiological changes that suggest the person is lying. There are other reasons that a person might not make eye contact, such as being on the autism spectrum or having certain psychological disorders, but Dan says the baseline of normal behavior is established for each individual subject. What examiners look for is a change or departure from the person's unique baseline.


A liar will not directly say they haven't done something wrong; they'll answer with a dodge, a question back at you, or a nonsequitor. Not answering directly is an immediate alarm bell to Dan. An innocent person will usually just say "no" when asked if they've done something wrong. "A guilty person has a hard time saying no," Dan says. When they don't answer the question, you might sniff out a lie.


Hand pointing

Another surefire trick of the treacherous is to over-explain. "They hard sell it to you, they go off on tangents, they ramble," Dan says. "They give you unimportant information." Or, they'll shift the blame onto someone else.

Dan, who lends his expertise to The Steve Wilkos Show, recently assessed a situation where an employee of a hotel was accused of stealing money from a hotel room. He polygraphed the entire hotel security staff, because it involved taking money from a safe that only they would have access to. When Dan questioned the accused employee, the man proclaimed his innocence and shifted the blame to his manager, Kara, and another employee named John. "When I said, 'Did you take the money?' he said, ‘I didn't take the money, it's that goddamn Kara, she's constantly favoring this one guy John because she grew up with him, and he's her boy,'" Dan recalls.

But John passed the polygraph, while the employee—who was guilty—failed it.


Liars also tend to change the story every time they tell it. In a recent case, Dan interviewed a man who was charged with stealing from his workplace and selling the items. He claimed to Dan that a security guard at the company had actually committed the crime. He even mentioned that he'd run into the security guard recently at a party. But conveniently, the man didn't know the guard's name or have his phone number. Lisa put him through a second interview, asking him the same questions, and "suddenly he knows the security guard's name and has his number," she says. This spelled a lie to Dan, and the polygraph results backed up his assessment.


"If the story doesn't make sense, it's usually not true," Dan says. In a recent case, a wife had agreed to take a polygraph at the request of her jealous husband, who had found numerous texts between her and a coworker on her phone. At first she told Dan that she and her colleague were merely friends who texted a lot, but that nothing physical happened between them. But as the polygraph went on, she added their communications went on for three years … and then confessed that they included nude photos of her.

She failed the polygraph—but then agreed to a second one, during which she denied having sexual contact with the friend. After she failed that test too, she admitted she had kissed the friend. (Even without these confessions, her body language throughout both tests was telling, Dan says; she was distraught and trembling. "I felt really bad for her," he admits. "I knew it wouldn't end well.")

"There's a saying: If it doesn't add up," Dan says, "it's usually because the truth wasn't in the equation."


Close-up of perspiring, tense, frowning young blonde woman

You breathe shallower when you lie, your face flushes, and you may begin to sweat. In addition, Dan says, "You lick your lips because digestion stops when fight or flight kicks in." Of course, these symptoms can also happen if you are genuinely afraid or have issues with authority, but according to Dan, this is where that valuable baseline of behavior helps an examiner determine if you were already nervous when you walked in.

Dan has one more tip that's useful no matter how astute your observational powers are: Get the person talking. He suggests approaching your line of questioning as an interview rather than an interrogation. "When I interview you, I let you talk," he notes. "In an interrogation, I'm doing the talking to get you to confess."


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