Some People Get 'Brain Tingles' From These Slime Videos. What's Behind The Feeling?

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When scientist Giulia Poerio was a little girl, she says she would experience this very peculiar — and distinct — feeling: "a warm, tingling sensation that starts at the crown of the head, almost like bubbles on the scalp."

Even more peculiar? It was triggered by specific sounds or gentle movements, "like watching my mom brush her hair or put makeup on," she recalls, or having her feet measured for school shoes or a teacher explain something to her very carefully.

That feeling now has a name: ASMR, described by those who experience it as involuntary "brain tingles" that are deeply calming and relaxing — and sometimes euphoric. And in the past decade, it has spawned a whole universe of online videos meant to trigger that feeling.

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These videos, which have racked up millions of views online, are often used to usher sleep or relieve stress. While some "ASMRtists" role-play scenarios (like this nine-hour video of a clinician coaxing you to sleep), others use props like a brush or paper. They'll act out classic ASMR triggers, such as light tapping, whispering, chewing or someone doing a manual task in a careful way (Bob Ross painting videos is a favorite), using high-quality microphones. All these videos are meant to induce that tingling sensation Poerio experienced as a kid, which is shared by untold others.

But what does science have to say about this phenomenon? Soon to be a lecturer at the University of Essex, Poerio is among the first to attempt scientific research on ASMR. She spoke with NPR's science podcast Short Wave and gave us a few quick takeaways.

ASMR Darling YouTube

1) ASMR has its roots in Internet lore, not science.

The first time that ASMR was discussed online, according to the website ASMR University, was in a 2007 thread called "Weird Sensation Feels Good" on the website SteadyHealth.com. Over the years, people with lifelong brain tingles began to find each other online and define the feeling among themselves. In 2010, Jennifer Allen dubbed it ASMR, which stands for "autonomous sensory meridian response."

But science is pretty mum on ASMR. Research is minimal, with roughly a dozen peer-reviewed, published studies on the topic. Without standard diagnostic criteria, it's unknown what percentage of the population experiences it. ASMR isn't even in the dictionary, though Merriam-Webster did add the term to its Words We're Watching list this year. Still, its popularity on the Internet continues to grow: The Super Bowl even aired a commercial this February featuring Zoë Kravitz drumming a beer with her fingernails — ASMR style.

2) ASMR is not the same thing as getting turned on.

Scientists who have studied ASMR say the feeling is not linked to sexual arousal.

In a 2018 study, published in the journal PLOS One, Poerio and a team of researchers hooked up dozens of participants who felt ASMR to biological feedback machinery.

"On average, heart rate decreased [by more than three beats per minute] when people watched ASMR videos, which is exactly the opposite of what you'd expect if it was a sexually arousing feeling," says Poerio, lead author of the paper.

However, ASMR participants also experienced increased skin conductance levels, a measure of autonomic nervous system arousal in the body. Taken together — lowered heart rate but heightened skin conductance — this pattern may be indicative of the emotional complexity of ASMR, which is both relaxing and euphoric, Poerio says.

"It's a little bit like music-induced chills or awe-inspired chills," says Poerio. "So sometimes if you hear an amazing speech — like a Martin Luther King speech — you might get those kind of those goose bumps, those shivers up your spine, which is a really kind of complex emotional aesthetic response that some people experience and other people don't."

3) The brains of people who experience ASMR may be slightly different from those of the rest of us (but scientists aren't sure how).

A 2015 study by Canadian researchers, published in Social Neuroscience, used an fMRI machine to scan the brains of 11 people who reported experiencing ASMR. They were not watching ASMR videos or other ASMR-triggering content.

Jojo's ASMR YouTube

The researchers looked at a part of the brain called the default mode network, which is associated with things such as daydreaming, mind-wandering and self-referential thought. They discovered that among these 11 ASMR participants, their brains were less able to inhibit sensory and emotional response compared with 11 control participants.

"We're getting loads of information from the senses all the time. As somebody who experiences ASMR, you may be less able to inhibit the link between what's coming in from the senses and the emotional reaction that you have," says Poerio, who was not involved in this study.

Keep in mind: This is one of just a handful of studies that have been done on the subject. The report concludes, "This initial study of the neural substrates of ASMR will hopefully serve as a catalyst for future investigations of this intriguing condition."

4) Whispering? Slime? Eating pickles? There's no set definition of ASMR, and the phenomenon keeps evolving online.

Online trends are getting slapped with the ASMR label all the time.

Slime videos are a recent example. Circulating on Instagram and YouTube, the videos show human hands poking and prodding a substance that's part solid, part liquid. The slime produces all kinds of sounds, from squelching to crunching to smacking.

Joseph Anthonii YouTube

Is slime an ASMR trigger? Maybe for some but not for everyone. For Poerio, slime videos fall more into another category of popular online videos called "oddly satisfying," rather than being a classic ASMR trigger. At the same time, she adds, the more that ASMR is linked to new trends and triggers, the more its meaning could change for people on the Internet.

"There's been quite a lot of interlocking between different kinds of trends. ASMR and slime and things like mukbang (live eating shows that began in South Korea) have all kind of piggybacked onto the ASMR trend."

5) The only way to know if you feel ASMR is to pop on a pair of headphones.

Not everyone experiences ASMR, but you won't know unless you try it. May we suggest listening to our podcast Short Wave for a sample? And if you recoil, don't fret. ASMR isn't for everyone, but those slime videos sure are mesmerizing.

The audio version of this story was produced by Brent Baughman and edited by Viet Le.