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Updated: May 14, 2026
04:47
Olfactory Context Dependent Memory: Direct Presentation of Odorants
Published on: September 18, 2018
Odor is a time cue for circadian behavior
1Laboratory of Chronobiology, Charité Universitätsmedizin Berlin, Berlin, Germany. ute.abraham@charite.de
Journal of Biological Rhythms
|February 6, 2013
Summary
Odors can act as a time cue, influencing circadian rhythms and locomotor behavior in mammals. This effect is more pronounced without the central pacemaker but still requires a functional internal clock.
Area of Science:
- Chronobiology
- Neuroscience
- Sensory Biology
Background:
- Circadian rhythms govern physiological and behavioral processes, synchronized by environmental cues like light and food.
- Odors provide critical fitness-related information and can vary with time of day.
Purpose of the Study:
- To investigate if odors function as a circadian time cue influencing mammalian locomotor behavior.
- To explore the role of the suprachiasmatic nucleus (SCN) and extra-SCN clocks in odor-mediated circadian effects.
Main Methods:
- Mice in running wheels were exposed to periodic artificial odor mixtures.
- Circadian activity rhythms were analyzed in intact, SCN-lesioned, and clock mutant mice.
Main Results:
- Rhythmic odor administration lengthened the period of circadian activity rhythms.
- Odor cues partially restored rhythmicity in SCN-lesioned mice.
- Odor effects were abolished in clock mutant mice, implicating extra-SCN canonical clocks.
Conclusions:
- Odor stimuli serve as a functional circadian time cue, modulating locomotor behavior.
- Odor-mediated circadian effects involve extra-SCN clocks and do not strictly require the SCN.
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