Assessment of the heart rate variability during arousal from sleep by Cohen’s class time-frequency distributions

Abstract

Arousal from sleep is a normal physiologic event which produces well defined changes in the sympatho-vagal balance. Arousal from sleep is related to sleep fragmentation and some sleep disorders as obstructive sleep apnea. However when repetitive arousals are found during sleep time, bad sleep quality and as consequence sleepiness during the day are associated. We studied the dynamic of the HRV during arousal accompanied by muscular activity. Ten isolated arousals free from any pathologic event where studied. Three Time- Frequency distributions (TFDs), Born-Jordan, Choi-Williams and Smooth Pseudo Wigner-Ville Distributions, were analyzed in order to evaluate their performance during arousal episodes. The three TFDs showed the same performance when analytic HRV signal is used. LF component suggests a major participation of the sympathetic activity at the beginning of the arousal episode while HF component suggests a major role of the parasympathetic drive at after arousal episode.