title: Automatic sleep detection using activity and facial electrodes.
abstract: The most commonly applied unobtrusive sleep monitoring method is actigraphy, the measurement of body limb movements. In spite of its wide clinical acceptance, actigraphy has a low specificity for sleep detection leaving room for novel approaches of unobtrusive sleep monitoring. The present study compared sleep detection by a novel single channel electro-oculography (EOG) method and three activity monitors, with the golden standard of polysomnographic sleep analysis as a reference. With standard actigraphy (Actiwatch placed at the left wrist) sleep detection specificity and sensitivity were 42% and 95%. With the Alive Monitor attached on the same wrist, activity-based sleep detection specificity and sensitivity were 40% and 97%. With another Alive Monitor placed over the sternum sleep detection specificity and sensitivity were 21% and 99%. With two self-applied EOG electrodes combined with automatic sleep detection analysis, specificity and sensitivity were 72% and 96%. The results confirm low specificity of actigraphic sleep estimates, and demonstrate that the novel single-channel EOG method provides a substantial improvement in specificity.
authors.affiliation: Sleep Laboratory, Brain and Work Research Center, Finnish Institute of Occupational Health, Helsinki, Finland. jussi.virkkala@ttl.fi
authors.forename: Jussi
authors.initials: J
authors.lastname: Virkkala
authors.forename: Joel
authors.initials: J
authors.lastname: Hasan
authors.forename: Riitta
authors.initials: R
authors.lastname: Velin
authors.forename: Sari-Leena
authors.initials: SL
authors.lastname: Himanen
authors.forename: Alpo
authors.initials: A
authors.lastname: Värri
authors.forename: Eus J W
authors.initials: EJ
authors.lastname: Van Someren
mesh_terms: D000328:Adult; D000465:Algorithms; D001698:Biomedical Engineering; D004566:Electrodes; D004585:Electrooculography / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data; D005145:Face; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D009043:Motor Activity; D017286:Polysomnography; D012680:Sensitivity and Specificity; D012890:Sleep / Q000502:physiology*; D014953:Wrist; D055815:Young Adult