Thread: Developing an EEG

I am going to build an EEG (http://en.wikipedia.org/wiki/EEG). I am sure I am capable of developing and building such a device. The only problem is, though, I don't know how an EEG works! I know voltages are measured at the scalp and some filters and amplifiers are applied to that. That's all I know.

Does anyone here know how an EEG works? What does it do to the signal it gets through the electrodes?

PS: Ofcourse I will release the schematics here. I'm sure this will come in handy researching sleep and dreams.

Oh, and could a mod move this to tech talk?