title: An automatic method for the recognition and classification of the A-phases of the cyclic alternating pattern.
abstract: OBJECTIVE
  The aim of this research has been to introduce an automatic method, simple from the mathematical and computational points of view, for the recognition and classification of the A-phases of the cyclic alternating pattern.
  
  
  METHODS
  The automatic method was based on the computation of 5 descriptors, which were derived from the EEG signal and were able to provide a meaningful data reduction. Each of them corresponded to a different frequency band.
  
  
  RESULTS
  The computation of these descriptors, followed by the introduction of two suitable thresholds and of simple criteria for logical discrimination, provided results which were in good agreement with those obtained with visual analysis. The method was versatile and could be applied to the study of other important microstructure phenomena by means of very small adaptations.
  
  
  CONCLUSIONS
  The simplicity of the method leads to a better understanding and a more precise definition of the visual criteria for the recognition and classification of the microstructure phenomena.
authors.affiliation: Istituto di Elaborazione della Informazione, Area della Ricerca, C.N.R., Via Moruzzi 1, I-56124 Pisa, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Navona
authors.forename: Umberto
authors.initials: U
authors.lastname: Barcaro
authors.forename: Enrica
authors.initials: E
authors.lastname: Bonanni
authors.forename: Fabio
authors.initials: F
authors.lastname: Di Martino
authors.forename: Michelangelo
authors.initials: M
authors.lastname: Maestri
authors.forename: Luigi
authors.initials: L
authors.lastname: Murri
mesh_terms: D000328:Adult; D000513:Alpha Rhythm; D001143:Arousal / Q000502:physiology; D004569:Electroencephalography; D001330:Electronic Data Processing; D006801:Humans; D008297:Male; D008390:Markov Chains; D017286:Polysomnography / Q000145:classification* / Q000379:methods; D012890:Sleep / Q000502:physiology*