Non-linear dynamics applied to human respiratory movement during sleep.
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.
Burioka
Naoto
N
Third Department of Internal Medicine, Faculty of Medicine, Tottori University, 36-1 Nishimachi, Yonago 683-8504, Japan. burioka@grape.med.tottori-u.ac.jp
Suyama
Hisashi
H
Sako
Takanori
T
Miyata
Masanori
M
Takeshima
Takao
T
Endo
Masahiro
M
Kurai
Jun
J
Fukuoka
Yasushi
Y
Takata
Miyata
M
Nomura
Takashi
T
Nakashima
Kenji
K
Shimizu
Eiji
E
D000328:Adult; D006801:Humans; D008297:Male; D017711:Nonlinear Dynamics; D015656:Respiratory Mechanics / Q000502:physiology*; D012890:Sleep / Q000502:physiology*; D018709:Statistics, Nonparametric