| Records |
| Author |
LeGates, T.A.; Altimus, C.M.; Wang, H.; Lee, H.-K.; Yang, S.; Zhao, H.; Kirkwood, A.; Weber, E.T.; Hattar, S. |
| Title |
Aberrant light directly impairs mood and learning through melanopsin-expressing neurons |
Type |
Journal Article |
| Year |
2012 |
Publication |
Nature |
Abbreviated Journal |
Nature |
| Volume |
491 |
Issue |
7425 |
Pages |
594-598 |
| Keywords |
Affect/drug effects/physiology/*radiation effects; Animals; Antidepressive Agents/pharmacology; Body Temperature Regulation/physiology/radiation effects; Circadian Rhythm/physiology; Cognition/drug effects/physiology/radiation effects; Corticosterone/metabolism; Depression/etiology/physiopathology; Desipramine/pharmacology; Fluoxetine/pharmacology; Learning/drug effects/physiology/*radiation effects; *Light; Long-Term Potentiation/drug effects; Male; Memory/physiology/radiation effects; Mice; Photoperiod; Retinal Ganglion Cells/drug effects/*metabolism/*radiation effects; *Rod Opsins/analysis; Sleep/physiology; Wakefulness/physiology |
| Abstract |
The daily solar cycle allows organisms to synchronize their circadian rhythms and sleep-wake cycles to the correct temporal niche. Changes in day-length, shift-work, and transmeridian travel lead to mood alterations and cognitive function deficits. Sleep deprivation and circadian disruption underlie mood and cognitive disorders associated with irregular light schedules. Whether irregular light schedules directly affect mood and cognitive functions in the context of normal sleep and circadian rhythms remains unclear. Here we show, using an aberrant light cycle that neither changes the amount and architecture of sleep nor causes changes in the circadian timing system, that light directly regulates mood-related behaviours and cognitive functions in mice. Animals exposed to the aberrant light cycle maintain daily corticosterone rhythms, but the overall levels of corticosterone are increased. Despite normal circadian and sleep structures, these animals show increased depression-like behaviours and impaired hippocampal long-term potentiation and learning. Administration of the antidepressant drugs fluoxetine or desipramine restores learning in mice exposed to the aberrant light cycle, suggesting that the mood deficit precedes the learning impairments. To determine the retinal circuits underlying this impairment of mood and learning, we examined the behavioural consequences of this light cycle in animals that lack intrinsically photosensitive retinal ganglion cells. In these animals, the aberrant light cycle does not impair mood and learning, despite the presence of the conventional retinal ganglion cells and the ability of these animals to detect light for image formation. These findings demonstrate the ability of light to influence cognitive and mood functions directly through intrinsically photosensitive retinal ganglion cells. |
| Address |
Department of Biology, Johns Hopkins University, Baltimore, Maryland 21218, USA |
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Place of Publication |
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| Language |
English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0028-0836 |
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| Notes |
PMID:23151476; PMCID:PMC3549331 |
Approved |
no |
Call Number  |
IDA @ john @ |
Serial |
238 |
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| Author |
Ruger, M.; St Hilaire, M.A.; Brainard, G.C.; Khalsa, S.-B.S.; Kronauer, R.E.; Czeisler, C.A.; Lockley, S.W. |
| Title |
Human phase response curve to a single 6.5 h pulse of short-wavelength light |
Type |
Journal Article |
| Year |
2013 |
Publication |
The Journal of Physiology |
Abbreviated Journal |
J Physiol |
| Volume |
591 |
Issue |
Pt 1 |
Pages |
353-363 |
| Keywords |
Adolescent; Adult; Body Temperature; Circadian Rhythm/*physiology; Female; Humans; *Light; Male; Melatonin/physiology; Young Adult; blue light; melatonin; photic response; whort-wavelength |
| Abstract |
The photic resetting response of the human circadian pacemaker depends on the timing of exposure, and the direction and magnitude of the resulting shift is described by a phase response curve (PRC). Previous PRCs in humans have utilized high-intensity polychromatic white light. Given that the circadian photoreception system is maximally sensitive to short-wavelength visible light, the aim of the current study was to construct a PRC to blue (480 nm) light and compare it to a 10,000 lux white light PRC constructed previously using a similar protocol. Eighteen young healthy participants (18-30 years) were studied for 9-10 days in a time-free environment. The protocol included three baseline days followed by a constant routine (CR) to assess initial circadian phase. Following this CR, participants were exposed to a 6.5 h 480 nm light exposure (11.8 muW cm(-2), 11.2 lux) following mydriasis via a modified Ganzfeld dome. A second CR was conducted following the light exposure to re-assess circadian phase. Phase shifts were calculated from the difference in dim light melatonin onset (DLMO) between CRs. Exposure to 6.5 h of 480 nm light resets the circadian pacemaker according to a conventional type 1 PRC with fitted maximum delays and advances of -2.6 h and 1.3 h, respectively. The 480 nm PRC induced approximately 75% of the response of the 10,000 lux white light PRC. These results may contribute to a re-evaluation of dosing guidelines for clinical light therapy and the use of light as a fatigue countermeasure. |
| Address |
Circadian Physiology Program, Division of Sleep Medicine, Brigham and Women's Hospital, Harvard Medical School, 221 Longwood Avenue, Boston, MA 02115, USA. mrueger@rics.bwh.harvard.edu |
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Place of Publication |
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English |
Summary Language |
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| ISSN |
0022-3751 |
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| Notes |
PMID:23090946; PMCID:PMC3630790 |
Approved |
no |
| Call Number |
IDA @ john @ |
Serial |
239 |
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| Author |
Chellappa, S.L.; Steiner, R.; Blattner, P.; Oelhafen, P.; Gotz, T.; Cajochen, C. |
| Title |
Non-visual effects of light on melatonin, alertness and cognitive performance: can blue-enriched light keep us alert? |
Type |
Journal Article |
| Year |
2011 |
Publication |
PloS one |
Abbreviated Journal |
PLoS One |
| Volume |
6 |
Issue |
1 |
Pages |
e16429 |
| Keywords |
Circadian Rhythm/radiation effects; Cognition/*radiation effects; Color; Cross-Over Studies; Fluorescence; Humans; *Light; Male; Melatonin/*radiation effects; Reaction Time/*radiation effects; Young Adult; blue light |
| Abstract |
BACKGROUND: Light exposure can cascade numerous effects on the human circadian process via the non-imaging forming system, whose spectral relevance is highest in the short-wavelength range. Here we investigated if commercially available compact fluorescent lamps with different colour temperatures can impact on alertness and cognitive performance. METHODS: Sixteen healthy young men were studied in a balanced cross-over design with light exposure of 3 different light settings (compact fluorescent lamps with light of 40 lux at 6500K and at 2500K and incandescent lamps of 40 lux at 3000K) during 2 h in the evening. RESULTS: Exposure to light at 6500K induced greater melatonin suppression, together with enhanced subjective alertness, well-being and visual comfort. With respect to cognitive performance, light at 6500K led to significantly faster reaction times in tasks associated with sustained attention (Psychomotor Vigilance and GO/NOGO Task), but not in tasks associated with executive function (Paced Visual Serial Addition Task). This cognitive improvement was strongly related with attenuated salivary melatonin levels, particularly for the light condition at 6500K. CONCLUSIONS: Our findings suggest that the sensitivity of the human alerting and cognitive response to polychromatic light at levels as low as 40 lux, is blue-shifted relative to the three-cone visual photopic system. Thus, the selection of commercially available compact fluorescent lights with different colour temperatures significantly impacts on circadian physiology and cognitive performance at home and in the workplace. |
| Address |
Centre for Chronobiology, Psychiatric Hospital of the University of Basel, Basel, Switzerland |
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English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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Edition |
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| ISSN |
1932-6203 |
ISBN |
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Conference |
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| Notes |
PMID:21298068; PMCID:PMC3027693 |
Approved |
no |
| Call Number |
IDA @ john @ |
Serial |
286 |
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| Author |
Landers, J.A.; Tamblyn, D.; Perriam, D. |
| Title |
Effect of a blue-light-blocking intraocular lens on the quality of sleep |
Type |
Journal Article |
| Year |
2009 |
Publication |
Journal of Cataract and Refractive Surgery |
Abbreviated Journal |
J Cataract Refract Surg |
| Volume |
35 |
Issue |
1 |
Pages |
83-88 |
| Keywords |
Aged; Aged, 80 and over; Circadian Rhythm/physiology; Female; Humans; *Lens Implantation, Intraocular; *Lenses, Intraocular; Light; Male; *Phacoemulsification; Prosthesis Design; Questionnaires; Sleep/*physiology; blue light; sleep |
| Abstract |
PURPOSE: To evaluate whether implantation of a blue-light-blocking intraocular lens (IOL) affects sleep quality. SETTING: Repatriation General Hospital, Adelaide, Australia. METHODS: This study comprised patients who had bilateral cataract surgery during the preceding 12 months with implantation of a conventional SI40NB IOL or an AcrySof Natural SN60WF blue-light-blocking IOL. Patients were contacted by telephone at least 6 months after second-eye surgery, and the Pittsburgh Sleep Quality Index (PSQI) questionnaire was administered. Results were compared between groups. RESULTS: Of the 49 patients, 31 received conventional IOLs and 18, blue-light-blocking IOLs. The mean age of the patients was 80 years +/- 8.1 (SD). The median PSQI score was 6 (interquartile range 3 to 8). There were no statistically significant differences in PSQI scores between the 2 IOL groups (P = .65). This remained true after adjustment for sex, age, medication, and time since surgery. CONCLUSION: The blue-light-blocking IOL had no effect on the sleep quality of patients, indicating that these IOLs might serve as an alternative to conventional IOLs without a detrimental effect on circadian rhythm. |
| Address |
Department of Ophthalmology, Repatriation General Hospital, Adelaide, Australia. john.landers@bigpond.com |
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Place of Publication |
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English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
0886-3350 |
ISBN |
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Conference |
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| Notes |
PMID:19101429 |
Approved |
no |
| Call Number |
IDA @ john @ |
Serial |
288 |
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| Author |
Smith, M.R.; Revell, V.L.; Eastman, C.I. |
| 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 |
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Place of Publication |
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English |
Summary Language |
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Original Title |
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Series Title |
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Abbreviated Series Title |
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Series Issue |
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Edition |
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| ISSN |
1389-9457 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
PMID:18805055; PMCID:PMC2723863 |
Approved |
no |
| Call Number |
IDA @ john @ |
Serial |
289 |
| Permanent link to this record |
