Delta, slow, less than 4Hz, large in amplitude, waking. Theta, waking and sleeping. Alpha, occipital, quiet waking. Mu, similar to alpha but in motor areas. Beta, gamma faster. Spindles, ripples. Faster frequency, lower amplitude for waking, opposite for nondreaming sleep states. Stages 1, 2, 3, 4, Awake, REM. 75% of sleep in non-REM, 25% in REM, periodic cycles beween states. Awake, stages 1 to 4, back 4 through 1 into REM, then repeat.