We just learned about the Theta Waves.
Another part of the science of sleep is Electroencephalography (EEG).
Sometimes to try and figure out if someone has a sleep problem, scientists can use this to test the different types of brain waves happening while you sleep.
To do an EEG they put stickers on your head, and hook them up to wires called electrodes which are hooked up to a computer to listen for any electricity your brain gives off.
(from: wikipedia - electroencephalography)
Kid Facts - Blast from the past: Tensor Tympani
