title: Information transfer through the spontaneous baroreflex in healthy humans.
abstract: OBJECTIVE
  This study assesses the information transfer through the spontaneous baroreflex (i.e. through the pathway linking systolic arterial pressure to heart period) during an experimental condition soliciting baroreflex (i.e. head-up tilt).
  
  
  METHODS
  The information transfer was calculated as the conditional entropy of heart period given systolic arterial pressure using a mutual neighbor approach and uniform quantization. The information transfer was monitored as a function of the forecasting time k.
  
  
  RESULTS
  We found that during head-up tilt the information transfer at k = 0 decreased but the rate of rise of information transfer as a function of k was faster.
  
  
  CONCLUSIONS
  We suggest that the characterization of the information transfer from systolic arterial pressure to heart period might complement the traditional characterization of the spontaneous baroreflex based on transfer function analysis.
authors.affiliation: Università degli Studi di Milano, Dipartimento di Tecnologie per la Salute, Istituto Ortopedico Galeazzi, Laboratorio di Modellistica di Sistemi Complessi, Via R. Galeazzi 4, 20161 Milan, Italy. alberto.porta@unimi.it
authors.forename: A
authors.initials: A
authors.lastname: Porta
authors.forename: A M
authors.initials: AM
authors.lastname: Catai
authors.forename: A C M
authors.initials: AC
authors.lastname: Takahashi
authors.forename: V
authors.initials: V
authors.lastname: Magagnin
authors.forename: T
authors.initials: T
authors.lastname: Bassani
authors.forename: E
authors.initials: E
authors.lastname: Tobaldini
authors.forename: N
authors.initials: N
authors.lastname: Montano
mesh_terms: D000328:Adult; D017704:Baroreflex / Q000502:physiology*; D003627:Data Interpretation, Statistical; D004562:Electrocardiography; D019277:Entropy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017156:Photoplethysmography; D012016:Reference Values; D012815:Signal Processing, Computer-Assisted; D013599:Systole / Q000502:physiology; D018667:Tilt-Table Test; D055815:Young Adult