[EazyC]

https://en.wikipedia.org/wiki/Local_field_potential

One of the most important ways the brain communicates is actually not just ionically through chemo-ionic channels but through summed wave activity. This is especially important in sleep and also during long term potentiation of circuits.

[TeMPOraL]

I don't see anything in this article implying that the brain actually reads the "summed wave activity" somehow; as far as I understand, everything here is just a description of how we measure and interpret EM fields generated by charges flying around in the brain. Is there any study that shows that some parts of the brain treat EM waves generated elsewhere as input?

[spin]

Buzsaki argues, in this book, that brain waves are the method that the brain uses to coordinate activity in different regions of the brain. (High-frequency waves coordinate the activity of small areas, low-frequency waves coordinate the activity of large areas.)

http://www.amazon.com/Rhythms-Brain-Gyorgy-Buzsaki/dp/019982...

If you're curious about brain waves, I highly recommend this book. It is fascinating.