title: EEG topography during sleep inertia upon awakening after a period of increased homeostatic sleep pressure.
abstract: OBJECTIVE
  Behavioral and physiological indexes of high sleep inertia (SI) characterize the awakening from recovery (REC) sleep after prolonged wakefulness, but the associated electroencephalogram (EEG) topography has never been investigated. Here, we compare the EEG topography following the awakening from baseline (BSL) and REC sleep.
  
  
  METHODS
  We have recorded the EEG waking activity of 26 healthy subjects immediately after the awakening from BSL sleep and from REC sleep following 40 h of prolonged wakefulness. In both BSL and REC conditions, 12 subjects were awakened from stage 2 sleep, and 14 subjects from rapid eye movement (REM) sleep. The full-scalp waking EEG (eyes closed) was recorded after all awakenings.
  
  
  RESULTS
  Subjects awakened from REC sleep showed a reduction of fronto-central alpha and beta-1 activities, while no significant effects of the sleep stage of awakening have been observed. Positive correlations between pre- and post-awakening EEG modifications following REC sleep have been found in the posterior and lateral cortices in the frequency ranges from theta to beta-2 and (only for REM awakenings) extending to the fronto-central regions in the beta-1 band, and in the midline central and parietal derivations for the alpha and delta bands, respectively.
  
  
  CONCLUSIONS
  These findings suggest that the higher SI after REC sleep may be due to the fronto-central decrease of alpha and beta-1 activity and to the persistence of the sleep EEG features after awakening in the posterior, lateral, and fronto-central cortices, without influences of the sleep stage of awakening.
authors.affiliation: Department of Psychology, "Sapienza" University of Rome, Rome, Italy. Electronic address: maurizio.gorgoni@uniroma1.it.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Gorgoni
authors.affiliation: Department of Life, Health and Environmental Sciences, University of L'Aquila, L'Aquila, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Ferrara
authors.affiliation: Department of Psychology, "Sapienza" University of Rome, Rome, Italy.
authors.forename: Aurora
authors.initials: A
authors.lastname: D'Atri
authors.affiliation: Department of Psychology, "Sapienza" University of Rome, Rome, Italy.
authors.forename: Giulia
authors.initials: G
authors.lastname: Lauri
authors.affiliation: Department of Psychology, "Sapienza" University of Rome, Rome, Italy.
authors.forename: Serena
authors.initials: S
authors.lastname: Scarpelli
authors.affiliation: Department of Psychology, "Sapienza" University of Rome, Rome, Italy.
authors.forename: Ilaria
authors.initials: I
authors.lastname: Truglia
authors.affiliation: Department of Psychology, "Sapienza" University of Rome, Rome, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: De Gennaro
mesh_terms: D000513:Alpha Rhythm / Q000502:physiology; D001143:Arousal / Q000502:physiology; D001611:Beta Rhythm / Q000502:physiology; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000503:physiopathology*; D020920:Dyssomnias / Q000503:physiopathology*; D004569:Electroencephalography; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology*; D006801:Humans; D008297:Male; D017286:Polysomnography; D012815:Signal Processing, Computer-Assisted; D012892:Sleep Deprivation / Q000503:physiopathology*; D012894:Sleep Stages / Q000502:physiology; D012895:Sleep, REM / Q000502:physiology; D013826:Theta Rhythm / Q000502:physiology; D014851:Wakefulness / Q000502:physiology*
keywords: Awakening; Cortical topography; EEG power; Local EEG changes; Sleep deprivation; Sleep inertia