Cardiorespiratory synchronization: is it a real phenomenon?

Presents a quantitative approach to the analysis of cardiorespiratory synchronization, which is a newly discovered phenomenon. The primary aim of this study is to determine whether cardiorespiratory synchronization is a real phenomenon or a random one. The authors utilized the surrogate data analysis approach. A surrogate data set was constructed from recordings of ECG and respiration obtained from 14 healthy adults. The surrogate data lacks the coupling between the heart and respiration. The real and surrogate data were subjected to a quantification algorithm in order to determine the statistical properties of synchronization in the two data sets. Synchronization was found in both the real and surrogate data. However, synchronization was significantly less abundant in the surrogate data. In view of those results, cardiorespiratory synchronization seems to be a real phenomenon, yet it probably does not play a crucial role in cardiorespiratory interaction