Differential impact in young and older individuals of blue-enriched white light on circadian physiology and alertness during sustained wakefulness

Gabel, V.; Reichert, C. F.; Maire, M.; Schmidt, Christina; Schlangen, L. J. M.; Kolodyazhniy, V.; Garbazza, C.; Cajochen, C.; Viola, A. U.

doi:10.1038/s41598-017-07060-8

Article (Scientific journals)

Differential impact in young and older individuals of blue-enriched white light on circadian physiology and alertness during sustained wakefulness

Gabel, V.; Reichert, C. F.; Maire, M. et al.

2017 • In Scientific Reports, 7 (1)

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10.1038/s41598-017-07060-8

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Abstract :

[en] We tested the effect of different lights as a countermeasure against sleep-loss decrements in alertness, melatonin and cortisol profile, skin temperature and wrist motor activity in healthy young and older volunteers under extendend wakefulness. 26 young [mean (SE): 25.0 (0.6) y)] and 12 older participants [(mean (SE): 63.6 (1.3) y)] underwent 40-h of sustained wakefulness during 3 balanced crossover segments, once under dim light (DL: 8 lx), and once under either white light (WL: 250 lx, 2,800 K) or blue-enriched white light (BL: 250 lx, 9,000 K) exposure. Subjective sleepiness, melatonin and cortisol were assessed hourly. Skin temperature and wrist motor activity were continuously recorded. WL and BL induced an alerting response in both the older (p = 0.005) and the young participants (p = 0.021). The evening rise in melatonin was attentuated under both WL and BL only in the young. Cortisol levels were increased and activity levels decreased in the older compared to the young only under BL (p = 0.0003). Compared to the young, both proximal and distal skin temperatures were lower in older participants under all lighting conditions. Thus the color temperature of normal intensity lighting may have differential effects on circadian physiology in young and older individuals. © 2017 The Author(s).

Disciplines :

Neurosciences & behavior

Author, co-author :

Gabel, V.; Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland, Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland, Department of Psychiatry and Behavioral Sciences, Stanford University, Palo Alto, CA, United States

Reichert, C. F.; Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland, Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland

Maire, M.; Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland, Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland

Schmidt, Christina ; Université de Liège - ULiège > Centre de recherches du cyclotron

Schlangen, L. J. M.; Philips Lighting Research, High Tech Campus 36, Eindhoven, Netherlands

Kolodyazhniy, V.; Ziemer Ophthalmic Systems AG, Port, Switzerland

Garbazza, C.; Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland, Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland

Cajochen, C.; Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland, Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland

Viola, A. U.; Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland, Transfaculty Research Platform Molecular and Cognitive Neurosciences, University of Basel, Basel, Switzerland, PPRS, Paris, France

Language :

English

Title :

Differential impact in young and older individuals of blue-enriched white light on circadian physiology and alertness during sustained wakefulness

Publication date :

2017

Journal title :

Scientific Reports

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2045-2322

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Nature Publishing Group

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