I'm torn about this sort of technology. On the one hand, the best way to drive adoption is external recording. On the other hand, the data are sooooo coarse-gra

I'm torn about this sort of technology. On the one hand, the best way to drive adoption is external recording. On the other hand, the data are sooooo coarse-grained. And on the third hand, we don't have anything resembling the theoretical framework we'd need to process any finer-grained data at the scale of the whole brain, so maybe this coarse-grained external recording really is the best first step. With those caveats, I do think this has potential important concrete applications, even if "mind reading" is likely beyond the scope. The fundamental question for these devices will not be one of neuroscience or practicality: the fundamental question will be how good is their signal-to-noise ratio (SNR). If they even approach clinical EEG SNR using their fNIRS, then these will be widely adopted, off the top of my head, for two uses: seizures and meditation (and the latter doesn't require anything even vaguely approaching clinical SNR). Epilepsy is one of the most prevalent neurological conditions (the most prevalent?) in the world, affecting more than 1% of people, and it's somewhat hard to diagnose effectively due to sparsity of seizures. You can only have patients hooked up to an EEG for so long, and you just have to hope that you get a seizure during that time. Especially when doing preliminary localization in preparation to surgically intervene (the only effective treatment in ~1/3 of epilepsy cases), you need to catch that seizure when it happens. So any vaguely cheap option that allows patients to monitor for seizures in their day-to-day will see widespread adoption by hospitals. (This doesn't even account for the potential to predict seizures by a matter of seconds or minutes, which can be invaluable for someone with moderately frequent seizures.) The meditation one sounds more out-there (especially if you read the OP article...), but is actually pretty well supported by studies. Particular results are debatable, but it's fairly well-established that meditation causes a large scale change in the frequency composition of brain waves that's pretty easy to capture on EEG. What's more, you can induce these changes consciously by providing feedback (e.g. a moving dot on a screen), a result demonstrated in monkeys (and I hope in humans, though I haven't seen that myself). There are still some lingering questions, such as the relative efficacy of inducing these changes via feedback vs via meditation, but they're questions at the level that they'll be overlooked by whatever company invites you to learn to meditate with these helmets. Intuitively, you could think of this as analogous to those posture-feedback devices I see advertised everywhere. Those notice your back is bending too much, and alert you. This would notice your thoughts are wandering, and alert you. A third, very vague, but important consequence of a device that (finally) has good SNR is the advent of a critical-mass hacker culture around brain-computer interfaces. If anyone knows anything about the SNR, or about more recent results on meditation, I'd love to read more.