Study Shows Psychopaths Don’t Catch Yawns

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iStock

People with psychopathic traits are less affected by others' yawns, a 2015 study finds. 

Contagious yawning has been linked to empathy levels in several studies, though not all research supports the association. However, new research in the journal Personality and Individual Differences finds that people with psychopathic traits—especially a lack of empathy—are not as susceptible to catching a case of the yawns ... at least among college students, the only group tested. 

Researchers from Baylor University in Texas tried to provoke 135 students to yawn in reaction to someone else’s yawn. Each of the participants also completed a questionnaire regarding their personality traits, measuring psychopathic characteristics like selfishness, tendency to be manipulative, impulsivity, and a lack of empathy. Then they sat at a computer and watched 10-second video clips of facial movements, including yawning. Electrodes were attached to their faces just under the lower eyelids, on their foreheads, on the outer corners of their eyes, and on their fingertips to measure their movements in reaction to the videos. 

Contagious yawning in a19th century etching. Image Credit: Wellcome Images via Wikimedia Commons // CC BY 4.0

The higher the participants rated on measures of cold-heartedness, the less likely they were to catch another person’s yawn. Granted, people are less likely to feel empathy with a stranger they’re watching in a video than with someone they know, and the sample size was pretty small, so Baylor University probably isn’t full of a bunch of raging psychopaths. And not yawning when others do it doesn’t mean you should run off for a psych evaluation. "But what we found tells us there is a neurological connection—some overlap—between psychopathy and contagious yawning,” study author Brian Rundle says

A Simple Skin Swab Could Soon Identify People at Risk for Parkinson's

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iStock.com/stevanovicigor

More than 200 years have passed since physician James Parkinson first identified the degenerative neurological disorder that bears his name. Over five million people worldwide suffer from Parkinson’s disease, a neurological condition characterized by muscle tremors and other symptoms. Diagnosis is based on those symptoms rather than blood tests, brain imaging, or any other laboratory evidence.

Now, science may be close to a simple and non-invasive method for diagnosing the disease based on a waxy substance called sebum, which people secrete through their skin. And it’s thanks to a woman with the unique ability to sniff out differences in the sebum of those with Parkinson's—years before a diagnosis can be made.

The Guardian describes how researchers at the University of Manchester partnered with a nurse named Joy Milne, a "super smeller" who can detect a unique odor emanating from Parkinson's patients that is unnoticeable to most people. Working with Tilo Kunath, a neurobiologist at Edinburgh University, Milne and the researchers pinpointed the strongest odor coming from the patients' upper backs, where sebum-emitting pores are concentrated.

For a new study in the journal ACS Central Science, the researchers analyzed skin swabs from 64 Parkinson's and non-Parkinson's subjects and found that three substances—eicosane, hippuric acid, and octadecanal—were present in higher concentrations in the Parkinson’s patients. One substance, perillic aldehyde, was lower. Milne confirmed that these swabs bore the distinct, musky odor associated with Parkinson’s patients.

Researchers also found no difference between patients who took drugs to control symptoms and those who did not, meaning that drug metabolites had no influence on the odor or compounds.

The next step will be to swab a a much larger cohort of Parkinson’s patients and healthy volunteers to see if the results are consistent and reliable. If these compounds are able to accurately identify Parkinson’s, researchers are optimistic that it could lead to earlier diagnosis and more effective interventions.

[h/t The Guardian]

World’s Oldest Stored Sperm Has Produced Some Healthy Baby Sheep

A stock photo of a lamb
A stock photo of a lamb
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It’s not every day that you stumble across a 50-year-old batch of frozen sheep sperm. So when Australian researchers rediscovered a wriggly little time capsule that had been left behind by an earlier researcher, they did the obvious: they tried to create some lambs. As Smithsonian reports, they pulled it off, too.

The semen, which came from several prize rams, had been frozen in 1968 by Dr. Steve Salamon, a sheep researcher from the University of Sydney. After bringing the sample out of storage, researchers thawed it out and conducted a few lab tests. They determined that its viability and DNA integrity were still intact, so they decided to put it to the ultimate test: Would it get a sheep pregnant? The sperm was artificially inseminated into 56 Merino ewes, and lo and behold, 34 of them became pregnant and gave birth to healthy lambs.

Of course, this experiment wasn’t just for fun. They wanted to test whether decades-old sperm—frozen in liquid nitrogen at -320°F—would still be viable for breeding purposes. Remarkably, the older sperm had a slightly higher pregnancy rate (61 percent) than sheep sperm that had been frozen for 12 months and used to impregnate ewes in a different experiment (in that case, the success rate was 59 percent).

“We believe this is the oldest viable stored semen of any species in the world and definitely the oldest sperm used to produce offspring,” researcher Dr. Jessica Rickard said in a statement.

Researchers say this experiment also lets them assess the genetic progress of selective breeding over the last five decades. “In that time, we’ve been trying to make better, more productive sheep [for the wool industry],” associate professor Simon de Graaf said. “This gives us a resource to benchmark and compare.”

[h/t Smithsonian]

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