Imagine listening to someone speaking slowly, or watching someone gently crinkling cellophane, and suddenly your head starts to tingle and a sensation of total relaxation washes over you -- it's what's sometimes known as "goose looping," or "attention-induced head orgasm."

It's a sensation that also goes by autonomous sensory meridian response, or ASMR: a non-clinical term for the relaxing, tingling feeling at the top of the head that proponents say can lead to a number of therapeutic, if scientifically unproven, benefits.

Brittany Connolly, a maker of ASMR videos, told The Huffington Post by email that ASMR clips have helped her through "both anxiety disorders and sleep problems." Likewise, Rebekah Smith, an ASMR video maker and curator, says she uses the videos to help her sleep at night, and that 75 percent of her followers online do as well.

But for all the online enthusiasm it's generated, ASMR has only the anecdotal support of its adherents to vouch for it. As Jessica Roy put it in Time magazine, "Scientists haven't yet provided many answers about ASMR and the phenomenon hasn't really been subject to any sort of rigorous study, meaning that the how and why surrounding it go largely unanswered."

Nevertheless, videos and sound clips said to trigger ASMR have become an Internet phenomenon: The largest ASMR community on Reddit has more than 64,000 members, while the most popular creators and curators of such videos on YouTube draw subscribers in the hundreds of thousands.

The "trigger" videos made by Smith, Connolly and other ASMR proponents skew toward the surreal: Triggers include hard-surface tapping, writing, scratching, crinkling cellophane, whispering, and accented or soothing voices. Eye exams are a popular subject for ASMR videos; so are haircuts, makeup tutorials and gentlemen's suit fittings. Some videos eschew role-play altogether and simply provide a medley of sounds.

At the far end of the spectrum, the videos get even more weird. Take for example Connolly's "Forest Nymph Role Play," or a young man using the handle "Ephemeral Rift" who has done a five part "ASMR zombie apocalypse tale."

The scenarios depicted in ASMR videos are very often intimate, but advocates are quick to point out that the videos are almost never sexual. Despite the "brain orgasm" moniker, the ASMR community is pushing to make sure the movement isn't associated with porn.

"I think that pornography caters to a more carnal desire, whereas ASMR aims to, for the most part, just be sensual," says Connolly. "ASMR (especially the role play kind of ASMR) is fruitful with that deeper connection that some people seek, the caring and kindness that pornography often lacks." Besides, says Connolly, "People are less apt to be open minded to something that they think is some kind of perversion."