sorry, as a last thought on this - every transmitter can transmit radio signals that are not communication signals and with the way that waves superimpose they can create frequencies outside their spec ranges. This , again, requires professional grade reception and analysis equipment to see what may be going on - I've been looking and such equipment is really expensive. Also, the data of human frequency responses is unavailable (no surprise) but I am sure such experiments have been done. Just brain frequencies can go up to maybe 200 Hz, possibly higher, but that would need transcranial data (as the skull is a partial insulator). And the way to get inside the brain is not by broadcasting, say a 10Hz signal as that won't work, but instead, say a 1000Hz and 1010Hz, so creating a 10Hz beat pattern.