AJP - Regulatory, Integrative and Comparative Physiology, Vol 271, Issue 3 501-R510, Copyright © 1996 by American Physiological Society

ARTICLES

Dynamics of the sleep EEG after an early evening nap: experimental data and simulations

E. Werth, D. J. Dijk, P. Achermann and A. A. Borbely
Institute of Pharmacology, University of Zurich, Switzerland.

Increasing sleep pressure is associated with highly predictable changes in the dynamics of the sleep electroencephalogram (EEG). To investigate whether the effects of reduced sleep pressure also can be accounted for by homeostatic mechanisms, nighttime sleep following an evening nap was recorded in healthy young men. In comparison with the baseline night, sleep latency in the postnap night was prolonged, rapid eye movement sleep (REMS) latency was reduced, and EEG power density in non-REMS was decreased in the delta and theta band. The buildup of both EEG slow-wave activity (SWA; power density in the 0.75-to 4.5-Hz range) and spindle frequency activity (SFA; power density in the 12.25-to 15.0-Hz range) in non-REMS episodes was diminished (SWA: episodes 1-3; SFA: episode 1). The typical declining trend of SWA over consecutive non-REM sleep episodes was attenuated. The time course of SWA could be closely simulated with a homeostatic model of sleep regulation, although some discrepancies in level and buildup of SWA were apparent. We conclude that homeostatic mechanisms can largely account for the dynamics of the sleep EEG under conditions of reduced sleep pressure.

This article has been cited by other articles:

				H. Murck, A. Steiger, R. M. Frieboes, and I. A. Antonijevic Pituitary adenylate cyclase-activating peptide affects homeostatic sleep regulation in healthy young men Am J Physiol Endocrinol Metab, March 1, 2007; 292(3): E853 - E857. [Abstract] [Full Text] [PDF]

				J. E. Larkin, T. Yokogawa, H. C. Heller, P. Franken, and N. F. Ruby Homeostatic regulation of sleep in arrhythmic Siberian hamsters Am J Physiol Regulatory Integrative Comp Physiol, July 1, 2004; 287(1): R104 - R111. [Abstract] [Full Text] [PDF]

				D.-J. Dijk and S. W. Lockley Functional Genomics of Sleep and Circadian Rhythm: Invited Review: Integration of human sleep-wake regulation and circadian rhythmicity J Appl Physiol, February 1, 2002; 92(2): 852 - 862. [Abstract] [Full Text] [PDF]

				P. Franken, D. Chollet, and M. Tafti The Homeostatic Regulation of Sleep Need Is under Genetic Control J. Neurosci., April 15, 2001; 21(8): 2610 - 2621. [Abstract] [Full Text] [PDF]

				R. Huber, T. Deboer, and I. Tobler Topography of EEG Dynamics After Sleep Deprivation in Mice J Neurophysiol, October 1, 2000; 84(4): 1888 - 1893. [Abstract] [Full Text] [PDF]

				T. Endo, C. Roth, H.-P. Landolt, E. Werth, D. Aeschbach, P. Achermann, and A. A. Borbely Selective REM sleep deprivation in humans: effects on sleep and sleep EEG Am J Physiol Regulatory Integrative Comp Physiol, April 1, 1998; 274(4): R1186 - R1194. [Abstract] [Full Text] [PDF]