title: Spectral analyses of electroencephalography and heart rate variability during sleep in normal subjects.
abstract: We investigated the relationship between electroencephalogram (EEG) activity and autonomic nervous system function using spectral analyses of EEG and heart rate variability (HRV) in healthy subjects during sleep. Eleven subjects were enrolled in this study. From EEG, the spectral edge frequencies (SEFs including SEF50, SEF90 and SEF95) were calculated. From electrocardiogram (ECG), the spectral powers of low-frequency band (LF: 0.04-0.15 Hz), high-frequency band (HF: 0.15-0.4 Hz) and the ratio of LF to HF (LF/HF) were calculated. During sleep, each set of data was obtained as the average of a 5-min measurement. We found that SEFs and LF/HF or LF decreased simultaneously and periodically, suggesting simultaneous depression of EEG activity and relative sympathetic activity, and SEFs significantly correlated with LF/HF and LF in all subjects during sleep, but not with HF. The existence of a clear correlation of SEFs with LF or LF/HF may offer a simple approach to estimate the relationship between EEG activity and autonomic nervous system function during sleep.
authors.affiliation: Department of Anesthesiology, Yokohama City University School of Medicine, 3-9, Fukuura, Kanazawa, Yokohama 236-0004, Japan. tetsuyam@med.yokohama-cu.ac.jp
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Miyashita
authors.forename: Kenichi
authors.initials: K
authors.lastname: Ogawa
authors.forename: Hideki
authors.initials: H
authors.lastname: Itoh
authors.forename: Yukiko
authors.initials: Y
authors.lastname: Arai
authors.forename: Minako
authors.initials: M
authors.lastname: Ashidagawa
authors.forename: Munehito
authors.initials: M
authors.lastname: Uchiyama
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Koide
authors.forename: Tomio
authors.initials: T
authors.lastname: Andoh
authors.forename: Yoshitsugu
authors.initials: Y
authors.lastname: Yamada
mesh_terms: D000328:Adult; D004562:Electrocardiography; D004569:Electroencephalography; D005260:Female; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D012016:Reference Values; D012890:Sleep / Q000502:physiology*