Looks like they use Transcranial Alternating Current Stimulation (tACS).
The military has been doing tDCS (direct current) experiments for a while for increased learning & performance.
I had a friend who used to swear by tDCS and did it very frequently. He attributed all kinds of mood & cognition improvements to it, including substantially reduced need for sleep, improved eyesight (he was born partially blind), etc. He also complained about migraines a lot and liked to experiment with all kinds of supplements, so YMMV.
Tried tDCS myself a handful of times, not for improved learning but for improved focus. If applied correctly it definitely has an effect that I'd consider better / stronger than a cup of coffee. I wouldn't feel comfortable doing it regularly though.
That reddit forum is full of "bro scientists" who use these methods are like hammers to bang the wetware without knowing how it works. Of course you get results when you mess with the system.
Reminds me of Alessandro Volta. In 1790, after inventing the battery, he stuck the the electrodes in his ears. He felt an explosion in his head, heard the sound of boiling “viscous matter" and passed out.
It would be nice if researchers could recruit these people to volunteer to be actual research subjects instead of messing with themselves and creating just anecdotes.
Some of the posts on that subreddit are seriously concerning. Burns on your head/arms seem to be common. One company in particular, "Foc.us", seems particularly dangerous.
Interesting tidbit: the foc.us manual says: "If you see white flashes (known as phosphenes), adjust the position of the foc.us headset away from your eyes"
Sorry, I've posted it on every tDCS article I've seen on HN, and no one has noticed it. It took three posts in this thread to get anyone to see it. I'm trying to help people be more cautious about their brain cells.
People keep posting tDCS articles without any warning about potential negative effects. There are a lot of young, impressionable people here who might experiment with what is put in front of them. I'd rather have people see the information and get myself downvoted in the process than keep watching articles like this get promoted without any warnings attached to them.
The military has been doing tDCS (direct current) experiments for a while for increased learning & performance.
I had a friend who used to swear by tDCS and did it very frequently. He attributed all kinds of mood & cognition improvements to it, including substantially reduced need for sleep, improved eyesight (he was born partially blind), etc. He also complained about migraines a lot and liked to experiment with all kinds of supplements, so YMMV.
Tried tDCS myself a handful of times, not for improved learning but for improved focus. If applied correctly it definitely has an effect that I'd consider better / stronger than a cup of coffee. I wouldn't feel comfortable doing it regularly though.
There's a subreddit that used to be pretty active: https://www.reddit.com/r/tDCS/
And here's a good Radiolab podcast, including DARPA Sniper experiments, etc: https://www.wnycstudios.org/story/9-volt-nirvana/