title: Critical scale invariance in a healthy human heart rate.
abstract: We demonstrate the robust scale-invariance in the probability density function (PDF) of detrended healthy human heart rate increments, which is preserved not only in a quiescent condition, but also in a dynamic state where the mean level of the heart rate is dramatically changing. This scale-independent and fractal structure is markedly different from the scale-dependent PDF evolution observed in a turbulentlike, cascade heart rate model. These results strongly support the view that a healthy human heart rate is controlled to converge continually to a critical state.
authors.affiliation: Educational Physiology Laboratory, Graduate School of Education, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Kiyono
authors.forename: Zbigniew R
authors.initials: ZR
authors.lastname: Struzik
authors.forename: Naoko
authors.initials: N
authors.lastname: Aoyagi
authors.forename: Seiichiro
authors.initials: S
authors.lastname: Sakata
authors.forename: Junichiro
authors.initials: J
authors.lastname: Hayano
authors.forename: Yoshiharu
authors.initials: Y
authors.lastname: Yamamoto
mesh_terms: D003198:Computer Simulation; D003627:Data Interpretation, Statistical; D006321:Heart / Q000502:physiology*; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008955:Models, Cardiovascular