Just a couple of thoughts:
Most of the EEG measuring equipment (where most of the data is taken) tends to have some pretty agressive low pass filters set with cut of points
below 50 Hz, some times narrow band pass, but even so multiple poles are required. Otherwise you would get a significant level of inductive noise from
all the AC current moving around. You are measuring really low voltage signals on the outside of the head.
Would be interested if anybody has update rates, links, on the latest PET,fMRI scanners, but I think these are quite slow.
Hence the 0.5-30+ Hz results usually quoted for EEG studies.
You would probably require a pretty well constructed faraday cage and be running your sensors digitisation on real clean DC to do it any other way.
Also the maximum firing rate of a neuron appears to be 1KHz according to this article:
psych.athabascau.ca...
I don't see a problem with parts of the brain operating over 120Hz, but EEG data is a measured average of coherrent activity on the outside brain.
"Suppose someone found out how to send this energy out, then built a machine for it. It's already been proven that sounds effect your brainwaves, so
it must be something within sound that generates the brainwaves."
Easy enough to try..
Favorite ways of messing externally messing with it..:
hemi-sync/binaural (monroe institute etc..) audio - seems to work quite well haven't tried frequencies>30Hz. Requires stereo headphones. Software for
this to help you validate your theory (have the suspicion that the mechanism of induction may only support a certain frequency range)
Must get round to trying frequency modulated ultrasonics/microwaves
modulated magnetic fields (been some interesting results here that web searches will find).
You can have so much **fun** with frequencies in the normal range.
Are you only interested to try inducing frequencies over 100Hz?