Next Article in Journal
Objective Food Intake in Night and Day Shift Workers: A Laboratory Study
Previous Article in Journal
Incidence of Daytime Sleepiness and Associated Factors in Two First Nations Communities in Saskatchewan, Canada
Open AccessArticle

Responses to Intermittent Light Stimulation Late in the Night Phase Before Dawn

1
Department of Psychology, University of Arizona, Tucson, AZ 85724, USA
2
Department of Neurology, University of Arizona, Tucson, AZ 85724, USA
3
BIO5 Institute, University of Arizona, Tucson, AZ 85724, USA
*
Author to whom correspondence should be addressed.
These authors contributed equally to this work.
Clocks & Sleep 2019, 1(1), 26-41; https://doi.org/10.3390/clockssleep1010004
Received: 15 August 2018 / Revised: 26 September 2018 / Accepted: 26 September 2018 / Published: 27 September 2018
The circadian clock is comprised of two oscillators that independently track sunset (evening) and sunrise (morning), though little is known about how light responses differ in each. Here, we quantified the morning oscillator’s responses to 19 separate pulse trains, collecting observations from over 1300 Drosophila at ZT23. Our results show that the advances in activity onset produced by these protocols depended on the tempo of light administration even when total exposure was conserved across a 15-min window. Moreover, patterns of stimulation previously shown to optimize the evening oscillator’s delay resetting at ZT13 (an hour after dusk) were equally effective for the M oscillator at ZT23 (an hour before dawn), though the morning oscillator was by comparison more photosensitive and could benefit from a greater number of fractionation strategies that better converted light into phase-shifting drive. These data continue to build the case that the reading frames for the pacemaker’s time-of-day estimates at dusk and dawn are not uniform and suggest that the “photologic” for the evening versus morning oscillator’s resetting might be dissociable. View Full-Text
Keywords: light; circadian; intermittent; photostimulation; phototherapy; advance zone light; circadian; intermittent; photostimulation; phototherapy; advance zone
Show Figures

Figure 1

MDPI and ACS Style

Kaladchibachi, S.; Negelspach, D.C.; Fernandez, F. Responses to Intermittent Light Stimulation Late in the Night Phase Before Dawn. Clocks & Sleep 2019, 1, 26-41.

Show more citation formats Show less citations formats

Article Access Map by Country/Region

1
Back to TopTop