https://doi.org/10.1140/epjb/e2008-00199-4
The effect of low-frequency oscillations on cardio-respiratory synchronization
Observations during rest and exercise
1
Department of Physics, University of Lancaster,
Lancaster LA1 4YB, UK
2
Nonlinear Dynamics and
Synergetics Group, Faculty of Electrical Engineering, University
of Ljubljana, Slovenia
Corresponding author: a aneta@lancaster.ac.uk
Received:
22
January
2008
Revised:
11
April
2008
Published online:
4
June
2008
We show that the transitions which occur between close orders of synchronization in the cardio-respiratory system are mainly due to modulation of the cardiac and respiratory processes by low-frequency components. The experimental evidence is derived from recordings on healthy subjects at rest and during exercise. Exercise acts as a perturbation of the system that alters the mean cardiac and respiratory frequencies and changes the amount of their modulation by low-frequency oscillations. The conclusion is supported by numerical evidence based on a model of phase-coupled oscillators, with white noise and low-frequency noise. Both the experimental and numerical approaches confirm that low-frequency oscillations play a significant role in the transitional behavior between close orders of synchronization.
PACS: 05.45.Xt – Synchronization; coupled oscillators / 87.19.ug – Heart and lung dynamics / 87.18.Tt – Noise in biological systems / 05.45.Tp – Time series analysis
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2008