Efficacy of a single sequence of intermittent bright light pulses for delaying circadian phase in humans. - Archive ouverte HAL Access content directly
Journal Articles AJP - Endocrinology and Metabolism Year : 2004

Efficacy of a single sequence of intermittent bright light pulses for delaying circadian phase in humans.

(1) , (1, 2) , (3) , (1) , (1)
1
2
3

Abstract

It has been shown in animal studies that exposure to brief pulses of bright light can phase shift the circadian pacemaker and that the resetting action of light is most efficient during the first minutes of light exposure. In humans, multiple consecutive days of exposure to brief bright light pulses have been shown to phase shift the circadian pacemaker. The aim of the present study was to determine whether a single sequence of brief bright light pulses administered during the early biological night would phase delay the human circadian pacemaker. Twenty-one healthy young subjects underwent a 6.5-h light exposure session in one of three randomly assigned conditions: 1) continuous bright light of approximately 9,500 lux, 2) intermittent bright light (six 15-min bright light pulses of approximately 9,500 lux separated by 60 min of very dim light of <1 lux), and 3) continuous very dim light of <1 lux. Twenty subjects were included in the analysis. Core body temperature (CBT) and melatonin were used as phase markers of the circadian pacemaker. Phase delays of CBT and melatonin rhythms in response to intermittent bright light pulses were comparable to those measured after continuous bright light exposure, even though the total exposure to the intermittent bright light represented only 23% of the 6.5-h continuous exposure. These results demonstrate that a single sequence of intermittent bright light pulses can phase delay the human circadian pacemaker and show that intermittent pulses have a greater resetting efficacy on a per minute basis than does continuous exposure.
Fichier principal
Vignette du fichier
inserm-00394458_edited.pdf (350.33 Ko) Télécharger le fichier
Vignette du fichier
Gronfier-Intermittent_Bright_Light_Circadian_Phase-Final_Accepted_Version.pdf (141.78 Ko) Télécharger le fichier
Origin : Files produced by the author(s)
Origin : Files produced by the author(s)
Loading...

Dates and versions

inserm-00394458 , version 1 (10-09-2009)

Identifiers

Cite

Claude Gronfier, Kenneth P. Wright, Richard E. Kronauer, Megan E. Jewett, Charles A. Czeisler. Efficacy of a single sequence of intermittent bright light pulses for delaying circadian phase in humans.: Phase delaying efficacy of intermittent bright light. AJP - Endocrinology and Metabolism, 2004, 287 (1), pp.E174-81. ⟨10.1152/ajpendo.00385.2003⟩. ⟨inserm-00394458⟩

Collections

INSERM
161 View
717 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More