I had no trouble assembling these, but I was surprised to see a fourth component: a small cylindrical spray bottle. While it's not strictly necessary, the Nervana designers recommend spraying a saline solution on the earbuds to facilitate electrical connection. An array of different sized earbuds are provided - music is piped to both ears, but the electrical charge only goes to the left ear.
A dial on the generator controls the intensity of the electrical pulse, which spikes along with the beat of the music. I had to crank up the dial quite a bit before I felt anything. The sensation is a bit uncomfortable at first, but certainly not painful. It's a buzzy tactile tingling that can also feel a little itchy.
I listened to various kinds of music with the Nervana device over the course of a week, in sessions of 30-45 minutes. The pulse sensation is more noticeable in music with a hard beat, like hip-hop, or with a sustained soft-loud dynamic. For the record, I got the best results with the Beastie Boys, A Tribe Called Quest, the Pixies and, naturally, Nirvana. Hey, what can I say - I heart the 1990s.
RELATED: Custom Earphones Double as Brainwave Monitors
I also used the device several times on the "Formula" setting, which sends timed electrical pulses regardless of audio input. It worked nicely with online streaming radio broadcasts of the MLB baseball playoffs.
While I never felt anything approaching a blissful high, I would estimate that about half of my listening sessions produced a discernible sense of relative relaxation, which lasted more than an hour after removing the earbuds. It was a very mild effect, at best, and it's impossible to say for sure whether the sensation came from the nerve stimulation, or the music, or the baseball. (The Giants loss to the Cubs was not relaxing.) The closest analog for the sensation, for me, is the feeling of mental relaxation after a long walk.
The Nervana designers have been clear in their promotions that "individual results may vary," as the old adage goes. You can read all about their user tests here. Ami Brannon, CEO and co-founder of Nervana, said that their internal data suggest Nervana can produce a wide range of effects.
"Just as our bodies are unique in their own way, everyone's Nervana experience is different," she said. "Results can differ based on your state of mind at the time of use. Users have described feeling a calm, relaxed sensation that allows them to take deeper breaths, tolerate chaos and focus more."
Nervana is currently on sale through the company website, just in time for the gift-giving season. Because, after all, nothing evokes the holiday spirit like stimulating your vagus nerve and firing electric pulses into your skull. Just like grandma used to say.
WATCH VIDEO: Can Shocking Your Brain Make You Smarter?