REGULARITY MEASURES FOR AUTONOMIC NERVOUS SYSTEM DATA: PSEUDOENTROPY AS A DYNAMIC MARY KER

摘要

The study of heart rate variability founds the foremostrnway to access to the role of the autonomic nervous systemrn(ANS) in cardiovascular regulation, in order to understandrnphysiological process in the homeostasis maintenance.rnIn last years, several signal processing methods werernproposed to understand the influence of the two mainrnbranches of the autonomic nervous system (sympatheticrnnervous system and vagal nervous system), based in time,rnfrequency and time-frequency methods, whose data isrnextracted in ECG records obtained in subjects duringrnstandard autonomic tests.rnTime-frequency methods constitute a great advance tornprocess this data, as they are suitable for nonstationarity,rnas is the case. However studies with too short records mayrnpresent some constrains.rnMethods from chaos theory have been recently used to thernstudy of the ANS, and by using this approach other nonclassicalrnmeasures of autonomic regulation are broughtrnforward.rnIn this work two psedoentropy measures are presentedrnand tested in heart rate variability and blood pressure data,rnusing short time series extracted from two phases of thernhead-up-tilt test.