Phase-dependent shift of free-running human circadian rhythms in response to a single bright pulse
- 126 Downloads
Responsiveness of free-running human circadian rhythms to a single pulse of bright light was examined in a temporal isolation unit. Bright light (5000 lx) of either 3 or 6 h duration, applied during the early subjective day, produced phase-advance shifts in both the sleep-wake cycle and the rhythm of rectal temperature; the light pulse had essentially no effect on the phase of the circadian rhythms, when it was introduced during the late subjective day or the early subjective night. The results indicate that bright light can reset the human circadian pacemaker.
Key wordsHuman circadian rhythm bright light pulse phase-shift temporal isolation phase response curve
Unable to display preview. Download preview PDF.
- 1.DeCoursey, P., Science131 (1960) 3.Google Scholar
- 2.Pittendrigh, C. S., in: Handbook of Behavioral Biology, vol. 4, Biological Rhythms, p. 95. Ed. J. Aschoff. Plenum Press, New York 1981.Google Scholar
- 6.Kram, K. R., J. interdisc. Cycle Res.7 (1976) 127.Google Scholar
- 7.Wever, R. A., The Circadian System of Man. Springer-Verlag, New York 1979.Google Scholar
- 10.Moore-Ede, M. C., and Czeisler, C. A., Mathematical Models of the Circadian Sleep-Wake Cycle. Raven Press, New York 1984.Google Scholar