title: Non-linear dynamics applied to human respiratory movement during sleep.
abstract: We investigated the relationship between approximate entropy (ApEn) and correlation dimension (D2) in respiratory movement to reveal the non-linear dynamics in respiration during sleep. Seven healthy volunteers participated in this study. We recorded respiratory movement during sleep at night. We estimated the values of D2 and ApEn in respiratory movement. A significant relationship was observed between ApEn and D2 during sleep (r = 0.67, P < 0.001). Surrogate data analysis revealed that the respiratory movements had significant non-linear property. This evidence suggests that ApEn and D2 may become new indices to evaluate non-linear respiratory dynamics during sleep.
authors.affiliation: Third Department of Internal Medicine, Faculty of Medicine, Tottori University, 36-1 Nishimachi, Yonago 683-8504, Japan. burioka@grape.med.tottori-u.ac.jp
authors.forename: Naoto
authors.initials: N
authors.lastname: Burioka
authors.forename: Hisashi
authors.initials: H
authors.lastname: Suyama
authors.forename: Takanori
authors.initials: T
authors.lastname: Sako
authors.forename: Masanori
authors.initials: M
authors.lastname: Miyata
authors.forename: Takao
authors.initials: T
authors.lastname: Takeshima
authors.forename: Masahiro
authors.initials: M
authors.lastname: Endo
authors.forename: Jun
authors.initials: J
authors.lastname: Kurai
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Fukuoka
authors.forename: Miyata
authors.initials: M
authors.lastname: Takata
authors.forename: Takashi
authors.initials: T
authors.lastname: Nomura
authors.forename: Kenji
authors.initials: K
authors.lastname: Nakashima
authors.forename: Eiji
authors.initials: E
authors.lastname: Shimizu
mesh_terms: D000328:Adult; D006801:Humans; D008297:Male; D017711:Nonlinear Dynamics; D015656:Respiratory Mechanics / Q000502:physiology*; D012890:Sleep / Q000502:physiology*; D018709:Statistics, Nonparametric