Nonlinear nature of spectral components in heart rate variability
心率变异性谱成分的非线性本质

We proposed a new hybrid method combining the band-phase-randomized surrogate data with noise titration to discern the influence of spectral components on heartbeat chaos. The results demonstrate that the chaotic strength of phase-randomized surrogate data in the high frequency band (HF) of heart rate variability (HRV) is reduced significantly, which indicates that the frequency components of spectral analysis involve intrinsic chaotic information. The hybrid method proposed in this study is effective to distinguish the different contributions of spectral components to chaotic strength of the test data. This method is applicable not only to HRV but also to other deterministic signals.