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Author Bedrosian, T.A.; Vaughn, C.A.; Galan, A.; Daye, G.; Weil, Z.M.; Nelson, R.J. url  doi
openurl 
  Title Nocturnal light exposure impairs affective responses in a wavelength-dependent manner Type Journal Article
  Year 2013 Publication The Journal of Neuroscience : the Official Journal of the Society for Neuroscience Abbreviated Journal J Neurosci  
  Volume 33 Issue 32 Pages 13081-13087  
  Keywords Analysis of Variance; Animals; Circadian Rhythm/*physiology; Cricetinae; Dose-Response Relationship, Radiation; Female; Food Deprivation/physiology; Food Preferences/physiology/radiation effects; Fourier Analysis; Gene Expression Regulation/radiation effects; Hippocampus/pathology/radiation effects; Immobility Response, Tonic/radiation effects; Light/*adverse effects; Mood Disorders/*etiology/pathology; Motor Activity/physiology/radiation effects; Phodopus; Proto-Oncogene Proteins c-fos/metabolism; Social Behavior; Suprachiasmatic Nucleus/metabolism; Time Factors  
  Abstract Life on earth is entrained to a 24 h solar cycle that synchronizes circadian rhythms in physiology and behavior; light is the most potent entraining cue. In mammals, light is detected by (1) rods and cones, which mediate visual function, and (2) intrinsically photosensitive retinal ganglion cells (ipRGCs), which primarily project to the suprachiasmatic nucleus (SCN) in the hypothalamus to regulate circadian rhythms. Recent evidence, however, demonstrates that ipRGCs also project to limbic brain regions, suggesting that, through this pathway, light may have a role in cognition and mood. Therefore, it follows that unnatural exposure to light may have negative consequences for mood or behavior. Modern environmental lighting conditions have led to excessive exposure to light at night (LAN), and particularly to blue wavelength lights. We hypothesized that nocturnal light exposure (i.e., dim LAN) would induce depressive responses and alter neuronal structure in hamsters (Phodopus sungorus). If this effect is mediated by ipRGCs, which have reduced sensitivity to red wavelength light, then we predicted that red LAN would have limited effects on brain and behavior compared with shorter wavelengths. Additionally, red LAN would not induce c-Fos activation in the SCN. Our results demonstrate that exposure to LAN influences behavior and neuronal plasticity and that this effect is likely mediated by ipRGCs. Modern sources of LAN that contain blue wavelengths may be particularly disruptive to the circadian system, potentially contributing to altered mood regulation.  
  Address Department of Neuroscience, Ohio State University Wexner Medical Center, Columbus, Ohio 43210, USA. Bedrosian.2@osu.edu  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0270-6474 ISBN Medium  
  Area Expedition Conference (up)  
  Notes PMID:23926261 Approved no  
  Call Number IDA @ john @ Serial 27  
Permanent link to this record
 

 
Author Evans, J.A.; Elliott, J.A.; Gorman, M.R. url  doi
openurl 
  Title Circadian effects of light no brighter than moonlight Type Journal Article
  Year 2007 Publication Journal of Biological Rhythms Abbreviated Journal J Biol Rhythms  
  Volume 22 Issue 4 Pages 356-367  
  Keywords Animals; Biological Clocks/physiology/*radiation effects; *Circadian Rhythm; Cricetinae; Dose-Response Relationship, Radiation; Lighting/*methods; Male; Mesocricetus; Motor Activity; Oscillometry; Photic Stimulation/methods; *Photoperiod; Physical Conditioning, Animal; Time Factors  
  Abstract In mammals, light entrains endogenous circadian pacemakers by inducing daily phase shifts via a photoreceptor mechanism recently discovered in retinal ganglion cells. Light that is comparable in intensity to moonlight is generally ineffective at inducing phase shifts or suppressing melatonin secretion, which has prompted the view that circadian photic sensitivity has been titrated so that the central pacemaker is unaffected by natural nighttime illumination. However, the authors have shown in several different entrainment paradigms that completely dark nights are not functionally equivalent to dimly lit nights, even when nighttime illumination is below putative thresholds for the circadian visual system. The present studies extend these findings. Dim illumination is shown here to be neither a strong zeitgeber, consistent with published fluence response curves, nor a potentiator of other zeitgebers. Nevertheless, dim light markedly alters the behavior of the free-running circadian pacemaker. Syrian hamsters were released from entrained conditions into constant darkness or dim narrowband green illumination (~0.01 lx, 1.3 x 10(-9) W/cm(2), peak lambda = 560 nm). Relative to complete darkness, constant dim light lengthened the period by ~0.3 h and altered the waveform of circadian rhythmicity. Among animals transferred from long day lengths (14 L:10 D) into constant conditions, dim illumination increased the duration of the active phase (alpha) by ~3 h relative to complete darkness. Short day entrainment (8 L:16 D) produced initially long alpha that increased further under constant dim light but decreased under complete darkness. In contrast, dim light pulses 2 h or longer produced effects on circadian phase and melatonin secretion that were small in magnitude. Furthermore, the amplitude of phase resetting to bright light and nonphotic stimuli was similar against dimly lit and dark backgrounds, indicating that the former does not directly amplify circadian inputs. Dim illumination markedly alters circadian waveform through effects on alpha, suggesting that dim light influences the coupling between oscillators theorized to program the beginning and end of subjective night. Physiological mechanisms responsible for conveying dim light stimuli to the pacemaker and implications for chronotherapeutics warrant further study.  
  Address Department of Psychology, University of California, San Diego, La Jolla, CA 92093, usa. jaevans@ucsd.edu  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0748-7304 ISBN Medium  
  Area Expedition Conference (up)  
  Notes PMID:17660452 Approved no  
  Call Number IDA @ john @ Serial 31  
Permanent link to this record
 

 
Author Kempenaers, B.; Borgstrom, P.; Loes, P.; Schlicht, E.; Valcu, M. url  doi
openurl 
  Title Artificial night lighting affects dawn song, extra-pair siring success, and lay date in songbirds Type Journal Article
  Year 2010 Publication Current Biology : CB Abbreviated Journal Curr Biol  
  Volume 20 Issue 19 Pages 1735-1739  
  Keywords Animals; Environmental Pollution; Female; Light; *Lighting; Male; *Reproduction; Sexual Behavior, Animal/*physiology; Songbirds/*physiology; Time Factors; *Vocalization, Animal  
  Abstract Associated with a continued global increase in urbanization, anthropogenic light pollution is an important problem. However, our understanding of the ecological consequences of light pollution is limited. We investigated effects of artificial night lighting on dawn song in five common forest-breeding songbirds. In four species, males near street lights started singing significantly earlier at dawn than males elsewhere in the forest, and this effect was stronger in naturally earlier-singing species. We compared reproductive behavior of blue tits breeding in edge territories with and without street lights to that of blue tits breeding in central territories over a 7 year period. Under the influence of street lights, females started egg laying on average 1.5 days earlier. Males occupying edge territories with street lights were twice as successful in obtaining extra-pair mates than their close neighbors or than males occupying central forest territories. Artificial night lighting affected both age classes but had a stronger effect on yearling males. Our findings indicate that light pollution has substantial effects on the timing of reproductive behavior and on individual mating patterns. It may have important evolutionary consequences by changing the information embedded in previously reliable quality-indicator traits.  
  Address Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, Eberhard-Gwinner-Strasse, 82319 Seewiesen, Germany. b.kempenaers@orn.mpg.de  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0960-9822 ISBN Medium  
  Area Expedition Conference (up)  
  Notes PMID:20850324 Approved no  
  Call Number IDA @ john @ Serial 51  
Permanent link to this record
 

 
Author Rockhill, A.P.; DePerno, C.S.; Powell, R.A. url  doi
openurl 
  Title The effect of illumination and time of day on movements of bobcats (Lynx rufus) Type Journal Article
  Year 2013 Publication PloS one Abbreviated Journal PLoS One  
  Volume 8 Issue 7 Pages e69213  
  Keywords Animals; Female; *Lighting; Lynx/*physiology; Male; Moon; Movement/*physiology; North Carolina; Time Factors; Wetlands  
  Abstract Understanding behavioral changes of prey and predators based on lunar illumination provides insight into important life history, behavioral ecology, and survival information. The objectives of this research were to determine if bobcat movement rates differed by period of day (dark, moon, crepuscular, day), lunar illumination (<10%, 10 – <50%, 50 – <90%, >90%), and moon phase (new, full). Bobcats had high movement rates during crepuscular and day periods and low movement rates during dark periods with highest nighttime rates at 10-<50% lunar illumination. Bobcats had highest movement rates during daytime when nighttime illumination was low (new moon) and higher movement rates during nighttime when lunar illumination was high (full moon). The behaviors we observed are consistent with prey availability being affected by light level and by limited vision by bobcats during darkness.  
  Address Fisheries, Wildlife, and Conservation Biology, North Carolina State University, Raleigh, North Carolina, USA. aimee_rockhill@ncsu.edu  
  Corporate Author Thesis  
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  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 1932-6203 ISBN Medium  
  Area Expedition Conference (up)  
  Notes PMID:23861963; PMCID:PMC3704646 Approved no  
  Call Number IDA @ john @ Serial 84  
Permanent link to this record
 

 
Author Wood, B.; Rea, M.S.; Plitnick, B.; Figueiro, M.G. url  doi
openurl 
  Title Light level and duration of exposure determine the impact of self-luminous tablets on melatonin suppression Type Journal Article
  Year 2013 Publication Applied Ergonomics Abbreviated Journal Appl Ergon  
  Volume 44 Issue 2 Pages 237-240  
  Keywords Adolescent; *Computers, Handheld; Female; Humans; Light/*adverse effects; Male; Melatonin/*biosynthesis; Photoperiod; Saliva/*metabolism; Sleep/radiation effects; Time Factors; Young Adult; melatonin  
  Abstract Exposure to light from self-luminous displays may be linked to increased risk for sleep disorders because these devices emit optical radiation at short wavelengths, close to the peak sensitivity of melatonin suppression. Thirteen participants experienced three experimental conditions in a within-subjects design to investigate the impact of self-luminous tablet displays on nocturnal melatonin suppression: 1) tablets-only set to the highest brightness, 2) tablets viewed through clear-lens goggles equipped with blue light-emitting diodes that provided 40 lux of 470-nm light at the cornea, and 3) tablets viewed through orange-tinted glasses (dark control; optical radiation <525 nm approximately 0). Melatonin suppressions after 1-h and 2-h exposures to tablets viewed with the blue light were significantly greater than zero. Suppression levels after 1-h exposure to the tablets-only were not statistically different than zero; however, this difference reached significance after 2 h. Based on these results, display manufacturers can determine how their products will affect melatonin levels and use model predictions to tune the spectral power distribution of self-luminous devices to increase or to decrease stimulation to the circadian system.  
  Address Lighting Research Center, Rensselaer Polytechnic Institute, 21 Union Street, Troy, NY 12180, USA. woodb5@rpi.edu  
  Corporate Author Thesis  
  Publisher Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0003-6870 ISBN Medium  
  Area Expedition Conference (up)  
  Notes PMID:22850476 Approved no  
  Call Number IDA @ john @ Serial 136  
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