title: A new method for the classification of subvigil stages, using the Fourier transform, and its application to sleep apnea.
abstract: An online classification for two-second segments of the EEG is developed. Based on the calculation of a norm and three characteristic frequencies the automatic classification shows satisfactory agreement with visual classification. The influence of the Fourier phase spectra is discussed. Trajectories in the parameter space are introduced. The automatic classification was applied to patients with a pronounced sleep-wake disorder and proved to be valuable in the diagnosis of a disturbed sleep structure.
authors.affiliation: Philipps-Universität Marburg, Fachbereich Physik, AG Systemstrukturen und Thermodynamik, F.R.G.
authors.forename: T
authors.initials: T
authors.lastname: Penzel
authors.forename: J
authors.initials: J
authors.lastname: Petzold
mesh_terms: D004569:Electroencephalography / Q000145:classification*; D005583:Fourier Analysis; D006801:Humans; D012016:Reference Values; D012891:Sleep Apnea Syndromes / Q000145:classification* / Q000503:physiopathology; D012894:Sleep Stages / Q000502:physiology; D014851:Wakefulness / Q000502:physiology*