Slow-wave activity (SWA) is believed to be a fundamental measure of sleep homeostasis and is frequently characterized as an exponentially declining periodic dynamical system. The objective of this study is to carry out the first rigorous statistical test of this hypothesized dynamical behavior.
Quantitative EEG and Sleep Research Laboratory, Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, P.O. Box 2908, Durham, NC 27710, USA.