>OK - So it appears in the EEG. As I read the original that started
>this, the acoustic 200hz enters one ear, the 204hz into the other
>and we get the 4hz EEG along with the original pair as
>corresponding EEGs. There must be information pathways that compare
>the signals coming from the 2 ears, *but this linkage is not
>necessarily relevant to the beat phenomenon*, rather to the need to
>determine the *source* of a sound - which is of *vital importance
>to survival*. The neural circuitry that achieves this - discrepancy
>detectors (in "computerese" - NAND circuits) is well understood
>and the 4hz EEG is just a bonus for piano tuners. It also accounts
>for our experience of the Doppler Effect.
Maybe you don't yet fully understand the implications involved in being
able to entrain brainwaves.
It means that we have a way to allow people to be able to learn to enter
certain states of conciousness at will.
For example, 4hz corresponds to the threshold between Delta and Theta
rhythms in the brain. Using the binaural beat phenomena allows us to have
a way to shift somebody from waking conciousness (beta) into deep sleep
(Delta) or anywhere else.