Figure 31

Changing amplitude of some components in a partial spectral element of the postnatal human heart rate chronome. Data from a healthy boy, born 19.10.1992, whose heart rate was measured at mostly 30-minute intervals from 20.10 for the ensuing 40 days, and analyzed as a gliding special window in separate weekly intervals, displaced in 12-hour increments through the data set. An initially greater prominence of infradians, shown by darker shading, corresponding to a larger amplitude, contrasts with the prominence of circadians and circasemidians in later weeks of life, while any ultradians with still higher frequencies and any trends and chaos, two other chronome elements, are here unassessed. Gliding spectral window of amplitudes of heart rate, focusing on infradians and circadians (view from the top; surface chart) in the first 40 days of life of a boy born at term (FW). The prominence of the infradian spectral components immediately after birth is apparent from shading [165, 166]. The change in shading observed around November 5 is an artefact related to a gap in the data collection. Original data of Yoshihiko Watanabe.