Summary: VOLUME 86, NUMBER 9 P H Y S I C A L R E V I E W L E T T E R S 26 FEBRUARY 2001
Magnitude and Sign Correlations in Heartbeat Fluctuations
Yosef Ashkenazy,1
Plamen Ch. Ivanov,1,2
Shlomo Havlin,3
Chung-K. Peng,2
Ary L. Goldberger,2
and H. Eugene Stanley1
1
Center for Polymer Studies and Department of Physics, Boston University, Boston, Massachusetts 02215
2
Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215
3
Department of Physics and Gonda Goldschmied Center, Bar-Ilan University, Ramat-Gan, Israel
(Received 16 May 2000)
We propose an approach for analyzing signals with long-range correlations by decomposing the signal
increment series into magnitude and sign series and analyzing their scaling properties. We show that
signals with identical long-range correlations can exhibit different time organization for the magnitude
and sign. We find that the magnitude series relates to the nonlinear properties of the original time series,
while the sign series relates to the linear properties. We apply our approach to the heartbeat interval

Source: Ashkenazy, Yossi "Yosef" - Department of Solar Energy and Environmental Physics, Jacob Blaustein Institutes for Desert Research,Ben-Gurion University of the Negev
Harvard University, Margret & H. A. Rey Institute for Nonlinear Dynamics in Medicine
Stanley, H. Eugene - Department of Physics, Boston University

Collections: Biology and Medicine; Computer Technologies and Information Sciences; Environmental Management and Restoration Technologies; Materials Science; Physics