finkel, A., Kupfer, D.J. (1991) Nonlinear analysis of EEG sleep states. Neuropsychopharmacology 5:167-176 259 HOUSE_OVERSIGHT_013759 Ehlers, C.L., Havstad, J., Prichard, D., Theiler, J. (1998) Low doses of ethanol reduce evidence for nonlinear structure in brain activity. J Neurosci 18:7474-86 Ehlers, C., Havstad,