Zusammenfassung
Fragestellung
Schläfrigkeit von Fahrzeugführern ist vermutlich eine Hauptursache von Verkehrsunfällen. Es gibt jedoch kein standardisiertes Verfahren zur Ermittlung der Schläfrigkeit zum Zeitpunkt des Unfalls. Die Schläfrigkeit wird mit einer neuen Kombination gewichteter Blinkvariablen gemessen und mit Infrarot Reflektions-Oculographie erfasst (Johns Drowsiness Skala oder JDS). Es wird untersucht, ob Leistungseinbrüche mit zwei verschiedenen Reaktionszeit-Tests und einem Fahrsimulator-Test korrelieren.
Methoden
31 gesunde Probanden absolvierten einen einfachen Reaktionszeittest (SRT) und einen Wahlreaktionszeittest (CRT) für 15 Minuten mit und ohne Schlafentzug für 27 bis 33 Stunden. Die Schläfrigkeit wurde jede Minute mit dem JDS (0–10) bestimmt. Zusätzlich fuhren 15 Probanden 70 Minuten lang mit dem Fahrsimulator mit und ohne Schlafentzug.
Ergebnisse
Beim CRT und beim SRT waren die Reaktionszeiten länger und die Fehler (keine Antwort innerhalb von 2 Sekunden nach Stimulus) häufiger. Die Häufigkeit von der Strasse zu fahren nahm zu und der JDS nahm signifikant zu. Das Risiko je Minute einen Fehler im SRT zu machen und mit dem Fahrsimulator von der Strasse zu fahren nahm parallel zu einem Anstieg des JDS zu (p < 0.001).
Schlussfolgerung
Das Risiko Leistungsfehler bei Schläfrigkeit zu machen ist mit hohen JDS Werten assoziiert. Der JDS spiegelt hauptsächlich Änderungen in der Charakteristik der Augenblinks wider. Hiermit kann die Basis für eine neue Methode gelegt werden welche die Schläfrigkeit kontinuierlich beim Fahren erfasst.
Summary
Question of the study
The drowsiness of drivers is believed to be a major cause of road crashes, but there is no standardized method for determining how drowsy a driver is or was at a particular time. This report describes how drowsiness, measured on a new scale (the Johns Drowsiness Scale or JDS) based on a weighted combination of ocular variables measured by infrared reflectance oculography, was related to performance failures in two different kinds of reaction-time (RT) tests as well as during simulated driving tests.
Methods
31 healthy volunteers performed simple (SRT) and choice (CRT) RT tests for 15 minutes with and without sleep deprivation for 27–33 hours. Their drowsiness was measured as a JDS score (0–10) each minute. In a separate experiment, 15 healthy young adults simulated driving in a car for about 70 minutes when alert and when sleep-deprived while their drowsiness was also measured.
Results
After sleep deprivation, RTs increased and errors of omission (failure to respond within 2 seconds from the start of the stimulus) occurred more frequently in both the SRT and CRT tests, the frequency of driving off the road increased, and JDS scores also increased significantly. The risk per minute for each subject of making an error of omission in SRT tests and of driving “off road” in a car simulator increased progressively with JDS scores (p < 0.001).
Conclusions
The risk of performance failure in the drowsy state is associated with high JDS scores, mainly reflecting changes in the characteristics of eyelid movements during blinks at the time. This could form the basis of a new method for continuously assessing the risks of drowsiness while driving.
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References
Pack AI, Pack AM, Rodgman E, Cucchiara A, Dinges DF, Schwab CW (1995) Characteristics of crashes attributed to the driver having fallen asleep. Accid Anal Prev 27:769–775
House of Representatives Standing Committee on Communication, Transport and the Arts. Beyond the Midnight Oil. Canberra, Australia, 2000
Austroads. Assessing fitness to drive. Austroads, Sydney, Australia, 2004
Brookhuis KA, De Waard D, Fairclough SH (2003) Criteria for driver impairment. Ergonomics 46:433–445
Johns MW (2003) The amplitude-velocity ratio of blinks: A new method for monitoring drowsiness. Sleep 26:A51
Johns MW, Tucker A (2005) The amplitudevelocity ratio of blinks: changes with drowsiness. Sleep 28:A122
Tucker A, Johns MW (2005) The duration of eyelid movements during blinks: changes with drowsiness. Sleep 28:A122
Johns MW, Tucker A, Chapman R, Crowley K, Michael NJ (2007) Monitoring eye and eyelid movements by infrared reflectance oculography to measure drowsiness in drivers. Somnologie 11:234–242
Morris TL, Miller JC (1996) Electrooculographic and performance indices of fatigue during simulated flight. Biol Psychol 42:343–60
Caffier PP, Erdmann U, Ullsperger P (2003) Experimental evaluation of eye-blink parameters as a drowsiness measure. Eur J Appl Physiol 89:319–325
Akerstedt T, Peters B, Anund A, Kecklund G (2005) Impaired alertness and performance driving home from the night shift: a driving simulator study. J Sleep Res 14:17–20
Galley N, Schleicher R, Galley L (2004) Blink parameters as indicators of driver's sleepiness-possibilities and limitations. In: Gale A (ed) Vision in Vehicles X. Elsevier, Amsterdam, pp 189–196
Van Orden KF, Jung TP, Makeig S (2000) Combined eye activity measures accurately estimate changes in sustained visual task performance. Biol Psychol 52:221–240
Åkerstedt T, Gillberg M (1990) Subjective and objective sleepiness in the active individual. Int J Neurosci 52:29–37
Dinges DF, Kribbs N (1991) Performance while sleepy: Effects of experimentally-induced sleepiness. In: Monk TH (ed) Sleep, Sleepiness and Performance. John Wiley & Sons, New York, pp 98–128
Johns MW, Tucker AJ, Chapman R, Michael NJ, Beale CA (2006) A new scale of drowsiness based on multiple characteristics of blinks: The Johns Drowsiness Scale. Sleep 29:A365
Tucker AJ, Chapman RC, Crowley KE, Johns MW, Papafotiou K, Stough C (1995) The effects of blood alcohol concentration on ocular measures of drowsiness. Unpublished
Stephan K, Hosking S, Regan M, Verdoorn A, Young K, Haworth N (2006) The relationship between driving performance and the Johns Drowsiness Scale as measured by the Optalert system. Monash Accident Research Centre, Monash University, Melbourne, Report No 252
Johns M, Hocking B (1997) Daytime sleepiness and sleep habits of Australian workers. Sleep 20:844–849
Chapman R, Johns MW, Crowley K (2006) In the drowsy state, errors of omission in a visual reaction-time test occur with eyes open or closed. Sleep 29:A364
Cummings P, Koepsell TD, Moffat JM, Rivara FP (2001) Drowsiness, counter-measures to drowsiness, and the risk of a motor vehicle crash. Inj Prev 7:194–199
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Potential conflict of interest statement
Sleep Diagnostics Pty Ltd is a research and development company that provided financial support for this research by way of part-time or full-time salaries for the researchers. Dr. Johns is also a share-holder of the company.
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Johns, M.W., Chapman, R., Crowley, K. et al. A new method for assessing the risks of drowsiness while driving. Somnologie 12, 66–74 (2008). https://doi.org/10.1007/s11818-008-0330-3
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DOI: https://doi.org/10.1007/s11818-008-0330-3