That's a pretty direct causal link between a measurable brain state and something as fundamental as "where does my body end?"
> With a third group of participants, they used a non-invasive technique called transcranial alternating current stimulation to speed up or slow down the frequency of a person's alpha waves. And sure enough, this seemed to correlate with how real a fake hand felt.
I know this is largely orthogonal to the article, and I know what “non-invasive” means and why it’s used in this sentence, but it made me chuckle - “this technique that changed the subject’s brain waves sufficient to literally impact their sense of self - but don’t worry! It’s non-invasive!”
OTH nearly all brain experiments are non-invasive. Did they mean to use the word to downplay how seriously impacting the experiment was?
Can things like meditation modify that? Or how about stuff like OOBE's like what some folks call astral projection? What do those practices to to the body's electric field?
https://pubmed.ncbi.nlm.nih.gov/20664147/
Meditation can alter a lot of “you” , and there is a reason you learn the advanced stuff under a guru (yoga mostly) or monk (buddhism).
There are some capacitive sensors (Electric Potential Integrated Circuit or EPIC) that can work through clothing fabric (which is a resistor). Within a few millimeters they are good enough for a diagnostic EKG. It's also used for stress monitoring, and can be embedded in a mattress or seat back.
There are also magnetoencephalography, magnetocardiography, magnetogastrography, and magnetomyography systems in use, which use superconducting quantum interference devices (SQUID). Those are orders of magnitude sensitive enough (10^-18 T sensitivity vs 10^-6 T to 10^-9 T for some body processes or 10^-15 T for neural activity).
> I _have_ a body, I _am_ a soul.
Maybe what they're identifying is the first half of that statement, how we interpret the former, through the presence of the latter.
But once you carry that reasoning to its full conclusion, the original argument for a "soul" or "self" that can even be meaningfully called "I" vanishes entirely. There still is some sort of underlying "true" subjective awareness that's felt to be ontologically basic in some sense (just like the "soul") but now it's entirely impersonal (the traditional term is "spirit", or "the absolute") since anything that's still personal is no longer comprised in it: an ongoing phenomenon and perhaps an inherent feature of existence itself, not a "thing".
Now run the same kinds of tests while listening to music, meditation, sleep, orgasm, psychoactive substances (including caffeine/alcohol/nicotine), during simulated stress event (hard slap in the face?), on different age groups, genders, races. Perhaps there are more than one version or definition of "You" that arises in certain circumstances.