Aside from whispering, some of the other things that can trigger the sensation include tapping or scratching sounds, the sound of rain, or white noise. And it’s not just sounds: People report getting ASMR when getting a haircut, or an ear exam—any kind of close, personal attention.

“Whenever they had lice checks in elementary school, I would feel very relaxed, and would have the tingling sensation run from my head and down my back,” Lee, who works for an advertising agency in New York City, says of her first ASMR experience.

For John Skinner, a 23-year-old tutor in Chicago, his introduction to ASMR came from famously-fro’d TV painter Bob Ross.

“Every time I watched it, I would just completely zone out… I guess I wouldn’t really call it sleepy, more just like very, very mellow,” he says. And he’s not the only one—the subreddit for ASMR lists Bob Ross under “Common Triggers.”

Some people prefer accented voices—Maria is Russian, and moved to the U.S. in 2006. When she heard I was interviewing Maria (YouTube name “GentleWhispering”), Lee got excited. “She’s my favorite,” Lee said. “It’s something about the way she pronounces consonants. Her P’s are like cushiony pillows.”

Maria says that as soon as she got to the U.S., she began searching for things that triggered her online. The videos she would find then were often not intended to trigger ASMR—it might just be a video of someone explaining something softly.

Then, “in 2009, I was going through a depression and I had a lot of problems with anxiety,” Maria says. “I needed something to relax. On YouTube I was watching hypnosis videos, some massage videos as well…then I saw a link that said ‘whisper video.’”

For around a year after that, she was just a viewer, watching the whisper videos every day for hours. “I liked them so much and was so happy that I found my people,” she says. “My depression totally disappeared.” Then she started making videos herself.

People like Maria, who make YouTube videos for ASMR (they call themselves ASMRtists), shape them around different triggers, to try to appeal to different people. Maria has a video in which she plays with a friend’s hair. Other “role-play” videos have a person pretending to do your makeup, or give you an eye exam.

According to Maria, the way ASMR manifests is different for everybody. First, there are two types, Type A and Type B. Those with Type A are said to be able to cause ASMR through meditation, or just thinking about a trigger, while Type Bs need to actually experience the trigger. Maria also says that the tingles vary in strength.

“The strongest type of tingle…feels like sparkles or little fireworks going off,” she says. “The strongest one would give you the feeling of being exhausted, pleasantly tired, satisfied almost you want to say. Then there are much less strong tingles, and they feel just pleasant. Almost like sand is being poured down your spine. [Or] like when you get the funny elbow, when you hit it and it feels like it just goes off everywhere.”

Neither Lee nor Skinner had a name for this sensation until recently. “I just thought it was a thing that everybody had,” Skinner says. The community that has sprung up around this specific physical sensation is, perhaps unsurprisingly, Internet-born and bred. It’s also sometimes called “Attention-Induced Euphoria,” though ASMR is the term that has caught on. According to Google, the term first showed up in 2011, increased in search popularity in 2012, and really took off this year.