Schumann resonance frequency I keep hearing that Schumann resonances have been increasing rapidly in recent years. And that it was relatively stable before. I failed to find any scientific data proving or disproving this. I would really appreciate a chart depicting what has been happening over the years in that concern.
 A: Of course, the Schumann resonance frequency can't constantly rise. We can see continuous fluctuation (with seasonality). As for "human brain resonance", I'd not call it "pseudo-science" (I'm referring to one of the comments above, unfortunately, I don't have enough reputation yet to write a comment).
There is nothing magic in the effect of electrical and magnetic fields on the nervous system, you can find that Adey and Blackman published tons of articles with proves.
That article also might be useful:
Cherry N. J., Human intelligence: The brain, an electromagnetic system synchronized by the Schumann Resonance signal // Human Sciences Department, Lincoln University, New Zealand. – 2003. – V.12. – №6. – P.843–844.
A: Do not pay attention, there are many hoaxes and pseudo-science around Schumann resonances... 
https://skeptoid.com/episodes/4352
A: Schumann resonances vary with losses in the cavity between Earth and the ionosphere and variability of the upper boundary due to atmospheric conductivity and ionospheric dynamics:

BALSER, M., WAGNER, C. Observations of Earth–Ionosphere Cavity Resonances. Nature 188, 638–641 (1960). https://doi.org/10.1038/188638a0

