title: Age-related changes in EEG coherence.
abstract: OBJECTIVE
  Coherence changes can reflect the pathophysiological processes involved in human ageing. We conducted a retrospective population study that sought to analyze the age-related changes in EEG coherence in a group of 17,722 healthy professional drivers.
  
  
  METHODS
  The EEGs were obtained using a standard 10-20 electrode configuration on the scalp. The recordings from 19 scalp electrodes were taken while the participants' eyes were closed. The linear correlations between the age and coherence were estimated by linear regression analysis.
  
  
  RESULTS
  Our results showed a significant decrease in coherence with age in the theta and alpha bands, and there was an increasing coherence with the beta bands. The most prominent changes occurred in the alpha bands. The delta bands contained movement artefacts, which most likely do not change with age.
  
  
  CONCLUSIONS
  The age-related EEG desynchrony can be partly explained by the age-related reduction of cortical connectivity. Higher frequencies of oscillations require less cortical area of high coherence. These findings explain why the lowest average coherence values were observed in the beta and sigma bands, as well as why the beta bands show borderline statistical significance and the sigma bands show non-significance. The age-dependent decrease in coherence may influence the estimation of age-related changes in EEG energy due to phase cancellation.
authors.affiliation: Department of Neurology, Charles University in Prague, Faculty Hospital Hradec Kralove, Czech Republic; Department of Computing and Control Engineering, Institute of Chemical Technology, Prague, Czech Republic. Electronic address: vysata@neurol.cz.
authors.forename: Oldrich
authors.initials: O
authors.lastname: Vysata
authors.affiliation: Czech Technical University in Prague, Faculty of Nuclear Sciences and Physical Engineering, Prague, Czech Republic.
authors.forename: Jaromir
authors.initials: J
authors.lastname: Kukal
authors.affiliation: Department of Computing and Control Engineering, Institute of Chemical Technology, Prague, Czech Republic.
authors.forename: Ales
authors.initials: A
authors.lastname: Prochazka
authors.affiliation: Neurocenter Caregroup, Rychnov nad Kneznou, Czech Republic.
authors.forename: Ladislav
authors.initials: L
authors.lastname: Pazdera
authors.affiliation: Department of Neurology, Charles University in Prague, Faculty Hospital Hradec Kralove, Czech Republic.
authors.forename: Julius
authors.initials: J
authors.lastname: Simko
authors.affiliation: Department of Neurology, Charles University in Prague, Faculty Hospital Hradec Kralove, Czech Republic.
authors.forename: Martin
authors.initials: M
authors.lastname: Valis
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D000465:Algorithms; D000513:Alpha Rhythm / Q000502:physiology; D001611:Beta Rhythm / Q000502:physiology; D003627:Data Interpretation, Statistical; D003700:Delta Rhythm / Q000502:physiology; D004569:Electroencephalography; D058407:Electroencephalography Phase Synchronization / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013826:Theta Rhythm / Q000502:physiology; D055815:Young Adult
keywords: Ageing; Coherence; Electroencephalogram; Normal values