The aim of this study was to investigate the effect of blue-enriched white light on the course of mood, sleepiness and light perception over the working day in a real work setting. The participants were 30 female office workers who were divided into two groups and exposed to two light conditions (blue-enriched white light and white light) in a counterbalanced order. Mood, sleepiness and light perception were measured three times a day on 2 days of each week. More pronounced effects of blue-enriched white light on energetic arousal were found in the morning and at midday when compared to the other times of the working day. At the beginning and the end of the work day, the workers seemed to be more sensitive to the brightness of blue-enriched white light while throughout the whole work day they seemed to be similarly sensitive to colour temperature.
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References
1.
BrainardGCHanifinJPGreesonJMByrneBGlickmanGGernerERollagMD. Action spectrum for melatonin regulation in humans: evidence for a novel circadian photoreceptor. Journal of Neuroscience2001; 21: 6405–6412.
2.
CajohenCMunchMKobialkaSKrauchiKSteinerROelhafenPOrgülSWirz-JusticeA. High sensitivity of human melatonin, alertness, thermoregulation and heart rate to short wavelength light. Journal of Clinical Endocrinology and Metabolism2005; 90: 1311–1316.
3.
LockleySWEvansEEScheerFABrainardGCCzeislerCAAeschbachD. Short-wavelength sensitivity for the direct effects of light on alertness, vigilance, and waking electroencephalogram in humans. Sleep2006; 29: 161–168.
4.
RevellVLArendtJFoggLFSkeneDJ. Alerting effects of light are sensitive to very short wavelengths. Neuroscience Letters2006; 399: 96–100.
5.
Phipps-NelsonJRedmanJRSchlangenLJMRajaratnamSMW. Blue light exposure reduces objective measures of sleepiness during prolonged nighttime performance testing. Chronobiology International2009; 26: 891–912.
GoldenRNGaynesBNEkstromRDHamerRMJacobseFMSuppesTWisnerKLNemeroffCB. The efficacy of light therapy in the treatment of mood disorders; a review and meta-analysis of the evidence. American Journal of Psychiatry2005; 162: 656–662.
8.
TermanM. Evolving applications of light therapy. Sleep Medicine Reviews2007; 11: 497–507.
9.
KnezIEnmarkerI. Effects of office lighting on mood and cognitive performance and a gender effect in work-related judgment. Environment and Behavior1998; 4: 580–594.
10.
VandewalleGSchwartzSGrandjeanDWuillaumeCBalteauEDegueldreCSchabusMPhillipsCLuxenADijkDJMaquetP. Spectral quality of light modulates emotional brain responses in humans. Proceedings of the National Academy of Sciences USA107: 19549–19554.
11.
KnezI. Effects of indoor lighting on mood and cognition. Journal of Environmental Psychology1995; 15: 39–51.
12.
MillsPMTomkinsSCSchlangenLJM. The effect of high correlated color temperature office lighting on employee wellbeing and work performance. Journal of Circadian Rhythms2007; 5: 2–10.
13.
ViolaAUJamesLMSchlangenLJMDijkD-J. Blue-enriched white light in the workplace improves self-reported alertness, performance and sleep quality. Scandinavian Journal of Work, Environment and Health2008; 34: 297–306.
14.
RautkylaEPoulakkaMTetriEHalonenL. Effects of correlated colour temperature and timing of light exposure on daytime alertness in lecture environments. Journal of Light and Visual Environment2010; 34: 2–59.
15.
HoffmanGGuflerVGriesmacherABartenbachCCanazeiMStagglSSchobersbergerW. Effects of variable lighting intensities and colour temperature on sulphatoxymelatonin and subjective mood in an experimental office workplace. Applied Ergonomics2008; 39: 719–728.
16.
HubalekSBrinkMSchierzC. Office worker’s daily exposure to light and its influence on sleep quality and mood. Lighting Research and Technology2010; 42: 33–50.
17.
GoryńskaE. Trójwymiarowy model nastroju – badania przymiotnikową skalą nastroju (UMACL). Studia Psychologiczne2005; 43: 35–46.
18.
MatthewsGJonesDMChamberlainAG. Refining the measurement of mood: The UWIST Mood Adjective Checklist. British Journal of Psychology1990; 81: 17–42.
19.
ÅkerstedtTGillbergM. Subjective and objective sleepiness in the active individual. International Journal of Neuroscience1990; 52: 29–37.
20.
AdanAGuardiaJ. Circadian variations of self-reported activation. A multidimensional approach. Chronobiologia1993; 20: 233–244.
21.
KnezI. Effects of colour of light on nonvisual psychological processes. Journal of Environmental Psychology2001; 21: 201–208.
22.
Rautkyla E, Teikari P, Puolakka M, Halonen, L. Evaluation of today’s research methods for assessing light-induced alertness: Proceedings of International Conference on the Effects of Light on Wellbeing, Eindhoven, The Netherlands, 26–27 October, 2009: 162–173.
