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The effect of low-frequency oscillations on cardio-respiratory synchronization: Observations during rest and exercise
D A Kenwright1, A Bahraminasab, A Stefanovska
1Department of Physics, University of Lancaster, Lancaster LA1 4YB, United Kingdom.
None:
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.
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