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Updated: Aug 29, 2026

Quantifying Infra-slow Dynamics of Spectral Power and Heart Rate in Sleeping Mice
Published on: August 2, 2017
Sleep states alter activity of suprachiasmatic nucleus neurons
Tom Deboer1, Mariska J Vansteensel, László Détári
1Department of Neurophysiology, Leiden University Medical Center, Box 9604, 2300 RC Leiden, Netherlands.
Abstract:
The timing of sleep and wakefulness in mammals is governed by a sleep homeostatic process and by the circadian clock of the suprachiasmatic nucleus (SCN), which has a molecular basis for rhythm generation. By combining SCN electrical activity recordings with electroencephalogram (EEG) recordings in the same animal (the Wistar rat), we discovered that changes in vigilance states are paralleled by strong changes in SCN electrophysiological activity. During rapid eye movement (REM) sleep, neuronal activity in the SCN was elevated, and during non-REM (NREM) sleep, it was lowered. We also carried out selective sleep deprivation experiments to confirm that changes in SCN electrical activity are caused by changes in vigilance state. Our results indicate that the 24-hour pattern in electrical activity that is controlled by the molecular machinery of the SCN is substantially modified by afferent information from the central nervous system.
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