There is this infamous DANCAVAS study [1] in which they ran cardiovascular screening on older population and found absolutely no benefit in doing so. Note that while the linked study claims there was a benefit to screening (reduced mortality in men aged 65-69), the apparent effect was caused by improper statistics (primary endpoint did not show benefit, only subgroup analysis, which however lacked statistical power to be reliable). And indeed, their follow up study showed that there was no benefit in the subgroup. [2]
Many a dollar is wasted every year on trying to prove population-wide screening prevents mortality or increases patients’ quality of life and every time we don’t cheat with statistics we get the same answer - population-wide screening isn’t effective.
I am pretty sure you’re right, they are probably recording alpha waves, possibly combined with heart rate.
Decoding limb joint movements from EEG scalp recordings is basically an unsolved problem (we can barely do it in lab with implants), I doubt an advertising company has cracked it.
There is quite a number of freely available EEG software for different paradigms (one such collection is MOABB - Mother of All BCI Benchmarks, and there’s a huge number of scientific articles).
The biggest bottleneck for a hobbyist is that when using EEG, most paradigms require somewhat expensive hardware to work and that most paradigms still don’t work well with scalp recordings outside a lab environment, even when using mid-cost devices.
There’s also the issue that classifiers usually have to be quite simple because datasets are small, because they are time consuming to record (and after you remove noisy epochs, you have even less data left). Cross-session and cross-subject learning rarely works, since EEG is dependent on so many factors like subjects’ brain anatomy, the type and precise location of electrodes, amount of gel (or lack thereof) and how dried out it is, mood and focus of the subjects, a huge number of environmental factors that influence subjects’ focus and many others.
The only paradigm I have seen to work a bit more reliably than others is Steady State Visual Potentials, because you have extra information that doesn’t need to be learned from EEG (the frequency of visual stimuli is roughly the same as the one in subjects’ occipital lobe).
But the 18th century artist who did portraits and wedding paintings is the today’s (wedding) photographer.
Does it take less money to commission a single wedding photo rather than a wedding painting? Yes. But many more people commission them and usually in tens to hundreds, together with videos, etc.
An 18th century wedding painter wasn’t in the business of paintings, but in the business of capturing memories and we do that today on much larger scale, more often and in a lot of different ways.
I’d also argue more landscape painters exist today than ever.
I assume you’re talking about another country, because in Denmark there was no general curfew under Covid (attendance to events might have required proof of negative COVID test or vaccination, but shops never did).
Many a dollar is wasted every year on trying to prove population-wide screening prevents mortality or increases patients’ quality of life and every time we don’t cheat with statistics we get the same answer - population-wide screening isn’t effective.
1: https://www.nejm.org/doi/full/10.1056/NEJMoa2208681 2: https://www.escardio.org/news/press/press-releases/No-signif...