title: Phase relationships between two or more interacting processes from one-dimensional time series. II. Application to heart-rate-variability data.
abstract: The recently proposed approach to detect synchronization from univariate data is applied to heart-rate-variability (HRV) data from ten healthy humans. The approach involves introducing angles for return times map and studying their behavior. For filtered human HRV data, it is demonstrated that: (i) in many of the subjects studied, interactions between different processes within the cardiovascular system can be considered as weak, and the angles can be well described by the derived model; (ii) in some of the subjects the strengths of the interactions between the processes are sufficiently large that the angles map has a distinctive structure, which is not captured by our model; (iii) synchronization between the processes involved can often be detected; (iv) the instantaneous radii are rather disordered.
authors.affiliation: Department of Physics, Lancaster University, Lancaster, LA1 4YB, United Kingdom.
authors.forename: N B
authors.initials: NB
authors.lastname: Janson
authors.forename: A G
authors.initials: AG
authors.lastname: Balanov
authors.forename: V S
authors.initials: VS
authors.lastname: Anishchenko
authors.forename: P V E
authors.initials: PV
authors.lastname: McClintock