And wonderful questions they are once, and if, there is a common starting point that the the Schumann resonance device is actually doing something. (I take no position on this - I was not even aware of the device until you mentioned it.)
(Just grabbing the comment Elk, nothing in the following is meant as direct)
I have a friend who runs an audio shop out of a large downtown apartment. Nice place. He's been experimenting with that type of device. He says it works, with regards to creating a more calm and coherent listening experience. This is in the downtown core of a city of, oh, 3 mil in the core area. So, based on a direct face to face question and answer, I'm inclined to look into it - considerably deeper. That resonance is one that the very idea of DNA was created under. It's a fundamentally important field, to the life on this planet.
As for electromagnetic manipulation, this can be done to the human brain and body---in just about any way you care to imagine. And matter..as well. Just because it's a difficult emotional hurdle--that has nothing to do with reality, or perception of it.
In my estimation...dismissing the resonance devices(if anyone is foolish enough to do so)...
...is a fools game, in the best of circumstances. Electromagnetics are critical to human function. Cities and urban life disrupt that to a very serious degree. You could not pay me enough to live in a giant pollution and electricity filled city, as I have far too much respect for my life to do that. To top it off..59.xHz..is the PERFECT frequency for stopping the human heart.
It's interesting that NTSC used almost exactly that number. and that 667hz,as an electromagnetic frequency to excite the human mind directly..is known as the 'God Frequency'.
I know a bit about that one too, as I had a friend, Andrew, who was right there at Laurentian University in Sudbury through that entire sequence of events and was also a test bunny. Andrew talked about the spooks and military that monitored the classes and experiments.
And guys like Troy Hurtubise, with the 'God light' and 'Angel Light'. Troy does not scare; He's been shot twice and stabbed 6 times. This shit is 100% for real. I've met the man-spoken directly with him. Have you? I'm from Northern Ontario, I go by Troy's place every time I visit my family. These are two examples out of a minimum 1000. Likely more.
Happens all the time, out there in the big wide world, and you might notice that it stays completely out of mainstream media. Even the scientific crowd has their little cliques and limits on reality that they will accept. Human, like everyone else. As screwed up as anyone.
All you need to do..is 'get it' once..and the rest will follow..as they say. Free your mind..and your ass will follow.