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Author Smith, M.R.; Revell, V.L.; Eastman, C.I. url  doi
openurl 
  Title Phase advancing the human circadian clock with blue-enriched polychromatic light Type Journal Article
  Year 2009 Publication Sleep Medicine Abbreviated Journal Sleep Med  
  Volume 10 Issue 3 Pages 287-294  
  Keywords Adult; Circadian Rhythm/*radiation effects; Female; Humans; *Light; Lighting/*methods; Male; Melatonin/metabolism; Phototherapy/*methods; Sleep; Wakefulness; Young Adult; blue light; sleep  
  Abstract BACKGROUND: Previous studies have shown that the human circadian system is maximally sensitive to short-wavelength (blue) light. Whether this sensitivity can be utilized to increase the size of phase shifts using light boxes and protocols designed for practical settings is not known. We assessed whether bright polychromatic lamps enriched in the short-wavelength portion of the visible light spectrum could produce larger phase advances than standard bright white lamps. METHODS: Twenty-two healthy young adults received either a bright white or bright blue-enriched 2-h phase advancing light pulse upon awakening on each of four treatment days. On the first treatment day the light pulse began 8h after the dim light melatonin onset (DLMO), on average about 2h before baseline wake time. On each subsequent day, light treatment began 1h earlier than the previous day, and the sleep schedule was also advanced. RESULTS: Phase advances of the DLMO for the blue-enriched (92+/-78 min, n=12) and white groups (76+/-45 min, n=10) were not significantly different. CONCLUSION: Bright blue-enriched polychromatic light is no more effective than standard bright light therapy for phase advancing circadian rhythms at commonly used therapeutic light levels.  
  Address Biological Rhythms Research Laboratory, Rush University Medical Center, Suite 425, 1645 W. Jackson Boulevard, Chicago, IL 60612, USA  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language (down) English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1389-9457 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:18805055; PMCID:PMC2723863 Approved no  
  Call Number IDA @ john @ Serial 289  
Permanent link to this record
 

 
Author Sharkey, K.M.; Carskadon, M.A.; Figueiro, M.G.; Zhu, Y.; Rea, M.S. url  doi
openurl 
  Title Effects of an advanced sleep schedule and morning short wavelength light exposure on circadian phase in young adults with late sleep schedules Type Journal Article
  Year 2011 Publication Sleep Medicine Abbreviated Journal Sleep Med  
  Volume 12 Issue 7 Pages 685-692  
  Keywords Affect/physiology/radiation effects; Circadian Rhythm/*physiology/*radiation effects; Color; Dose-Response Relationship, Radiation; Female; Humans; *Light; Male; Melatonin/metabolism; Photoperiod; Phototherapy/*methods; Saliva/metabolism; Sleep/physiology/radiation effects; Sleep Disorders, Circadian Rhythm/prevention & control/*therapy; Stress, Psychological/prevention & control/therapy; Treatment Outcome; Young Adult; blue light  
  Abstract OBJECTIVE: We examined the effects of an advanced sleep/wake schedule and morning short wavelength (blue) light in 25 adults (mean age+/-SD=21.8+/-3 years; 13 women) with late sleep schedules and subclinical features of delayed sleep phase disorder (DSPD). METHODS: After a baseline week, participants kept individualized, fixed, advanced 7.5-h sleep schedules for 6days. Participants were randomly assigned to groups to receive “blue” (470nm, approximately 225lux, n=12) or “dim” (<1lux, n=13) light for 1h after waking each day. Head-worn “Daysimeters” measured light exposure; actigraphs and sleep diaries confirmed schedule compliance. Salivary dim light melatonin onset (DLMO), self-reported sleep, and mood were examined with 2x2 ANOVA. RESULTS: After 6days, both groups showed significant circadian phase advances, but morning blue light was not associated with larger phase shifts than dim-light exposure. The average DLMO advances (mean+/-SD) were 1.5+/-1.1h in the dim light group and 1.4+/-0.7h in the blue light group. CONCLUSIONS: Adherence to a fixed advanced sleep/wake schedule resulted in significant circadian phase shifts in young adults with subclinical DSPD with or without morning blue light exposure. Light/dark exposures associated with fixed early sleep schedules are sufficient to advance circadian phase in young adults.  
  Address Department of Medicine, Division of Pulmonary, Critical Care, and Sleep Medicine, Alpert Medical School of Brown University, Box G-RIH, Providence, RI 02912, USA. katherine_sharkey@brown.edu  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language (down) English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1389-9457 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:21704557; PMCID:PMC3145013 Approved no  
  Call Number IDA @ john @ Serial 303  
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Author Kessel, L.; Siganos, G.; Jorgensen, T.; Larsen, M. url  doi
openurl 
  Title Sleep disturbances are related to decreased transmission of blue light to the retina caused by lens yellowing Type Journal Article
  Year 2011 Publication Sleep Abbreviated Journal Sleep  
  Volume 34 Issue 9 Pages 1215-1219  
  Keywords Adult; Age Factors; Aging/*pathology/physiology; Circadian Rhythm/physiology; Cross-Sectional Studies; Female; Fluorometry; Humans; Lens, Crystalline/*pathology/physiopathology; *Light; Male; Middle Aged; Retina/*physiopathology; Risk Factors; *Scattering, Radiation; Sleep Disorders/*etiology; Circadian rhythm; cataract; melanopsin; sleep; blue light  
  Abstract STUDY OBJECTIVES: Sleep pattern and circadian rhythms are regulated via the retinohypothalamic tract in response to stimulation of a subset of retinal ganglion cells, predominantly by blue light (450-490 nm). With age, the transmission of blue light to the retina is reduced because of the aging process of the human lens, and this may impair the photoentrainment of circadian rhythm leading to sleep disorders. The aim of the study was to examine the association between lens aging and sleep disorders. DESIGN: Cross-sectional population based study. SETTING: The study was performed at the Research Center for Prevention and Health, Glostrup Hospital, Denmark and at the Department of Ophthalmology, Herlev Hospital, Denmark. PARTICIPANTS: An age- and sex-stratified sample of 970 persons aged 30 to 60 years of age drawn from a sample randomly selected from the background population. INTERVENTIONS: Not applicable. MEASUREMENTS AND RESULTS: Sleep disturbances were evaluated by a combination of questionnaire and the use of prescription sleeping medication. Lens aging (transmission and yellowing) was measured objectively by lens autofluorometry. The risk of sleep disturbances was significantly increased when the transmission of blue light to the retina was low, even after correction for the effect of age and other confounding factors such as smoking habits, diabetes mellitus, gender, and the risk of ischemic heart disease (P < 0.0001). CONCLUSIONS: Filtration of blue light by the aging lens was significantly associated with an increased risk of sleep disturbances. We propose that this is a result of disturbance of photoentrainment of circadian rhythms.  
  Address Department of Ophthalmology, Glostrup Hospital, University of Copenhagen, Denmark. line.kessel@dadlnet.dk  
  Corporate Author Thesis  
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  Language (down) English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0161-8105 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:21886359; PMCID:PMC3157663 Approved no  
  Call Number IDA @ john @ Serial 344  
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Author Mottram, V.; Middleton, B.; Williams, P.; Arendt, J. url  doi
openurl 
  Title The impact of bright artificial white and 'blue-enriched' light on sleep and circadian phase during the polar winter Type Journal Article
  Year 2011 Publication Journal of Sleep Research Abbreviated Journal J Sleep Res  
  Volume 20 Issue 1 Pt 2 Pages 154-161  
  Keywords Adult; Circadian Rhythm/*physiology; *Cold Climate; Female; Humans; *Light; Male; Medical Records; Questionnaires; Sleep/*physiology; Time Factors; blue light  
  Abstract Delayed sleep phase (and sometimes free-run) is common in the Antarctic winter (no natural sunlight) and optimizing the artificial light conditions is desirable. This project evaluated sleep when using 17,000 K blue-enriched lamps compared with standard white lamps (5000 K) for personal and communal illumination. Base personnel, 10 males, five females, 32.5+/-8 years took part in the study. From 24 March to 21 September 2006 light exposure alternated between 4-5-week periods of standard white (5000 K) and blue-enriched lamps (17,000 K), with a 3-week control before and after extra light. Sleep and light exposure were assessed by actigraphy and sleep diaries. General health (RAND 36-item questionnaire) and circadian phase (urinary 6-sulphatoxymelatonin rhythm) were evaluated at the end of each light condition. Direct comparison (rmanova) of blue-enriched light with white light showed that sleep onset was earlier by 19 min (P=0.022), and sleep latency tended to be shorter by 4 min (P=0.065) with blue-enriched light. Analysing all light conditions, control, blue and white, again provided evidence for greater efficiency of blue-enriched light compared with white (P<0.05), but with the best sleep timing, duration, efficiency and quality in control natural light conditions. Circadian phase was earlier on average in midwinter blue compared with midwinter white light by 45 min (P<0.05). Light condition had no influence on general health. We conclude that the use of blue-enriched light had some beneficial effects, notably earlier sleep, compared with standard white light during the polar winter.  
  Address British Antarctic Survey Medical Unit, Derriford Hospital, Plymouth, UK  
  Corporate Author Thesis  
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  Language (down) English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0962-1105 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:20723022 Approved no  
  Call Number IDA @ john @ Serial 348  
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Author Shochat, T. url  doi
openurl 
  Title Impact of lifestyle and technology developments on sleep Type Journal Article
  Year 2012 Publication Nature and Science of Sleep Abbreviated Journal Nat Sci Sleep  
  Volume 4 Issue Pages 19-31  
  Keywords Human Health; behavior; lifestyle; sleep; technology  
  Abstract Although the physiological and psychological mechanisms involved in the development of sleep disorders remain similar throughout history, factors that potentiate these mechanisms are closely related to the “zeitgeist”, ie, the sociocultural, technological and lifestyle trends which characterize an era. Technological advancements have afforded modern society with 24-hour work operations, transmeridian travel and exposure to a myriad of electronic devices such as televisions, computers and cellular phones. Growing evidence suggests that these advancements take their toll on human functioning and health via their damaging effects on sleep quality, quantity and timing. Additional behavioral lifestyle factors associated with poor sleep include weight gain, insufficient physical exercise and consumption of substances such as caffeine, alcohol and nicotine. Some of these factors have been implicated as self-help aids used to combat daytime sleepiness and impaired daytime functioning. This review aims to highlight current lifestyle trends that have been shown in scientific investigations to be associated with sleep patterns, sleep duration and sleep quality. Current understanding of the underlying mechanisms of these associations will be presented, as well as some of the reported consequences. Available therapies used to treat some lifestyle related sleep disorders will be discussed. Perspectives will be provided for further investigation of lifestyle factors that are associated with poor sleep, including developing theoretical frameworks, identifying underlying mechanisms, and establishing appropriate therapies and public health interventions aimed to improve sleep behaviors in order to enhance functioning and health in modern society.  
  Address Department of Nursing, Faculty of Social Welfare and Health Sciences, University of Haifa, Haifa, Israel  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language (down) English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1179-1608 ISBN Medium  
  Area Expedition Conference  
  Notes PMID:23616726; PMCID:PMC3630968 Approved no  
  Call Number LoNNe @ christopher.kyba @ Serial 515  
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