title: Dynamic neuronal network organization of the circadian clock and possible deterioration in disease.
abstract: In mammals, the suprachiasmatic nuclei (SCNs) function as a circadian pacemaker that drives 24-h rhythms in physiology and behavior. The SCN is a multicellular clock in which the constituent oscillators show dynamics in their functional organization and phase coherence. Evidence has emerged that plasticity in phase synchrony among SCN neurons determines (i) the amplitude of the rhythm, (ii) the response to continuous light, (iii) the capacity to respond to seasonal changes, and (iv) the phase-resetting capacity. A decrease in circadian amplitude and phase-resetting capacity is characteristic during aging and can be a result of disease processes. Whether the decrease in amplitude is caused by a loss of synchronization or by a loss of single-cell rhythmicity remains to be determined and is important for the development of strategies to ameliorate circadian disorders.
authors.affiliation: Laboratory for Neurophysiology, Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands. Electronic address: j.h.meijer@lumc.nl.
authors.forename: Johanna H
authors.initials: JH
authors.lastname: Meijer
authors.affiliation: Laboratory for Neurophysiology, Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands; Laboratory of Circadian and Sleep Medicine, Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, CA, USA.
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Colwell
authors.affiliation: Laboratory for Neurophysiology, Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Jos H T
authors.initials: JHT
authors.lastname: Rohling
authors.affiliation: Laboratory for Neurophysiology, Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Thijs
authors.initials: T
authors.lastname: Houben
authors.affiliation: Laboratory for Neurophysiology, Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Stephan
authors.initials: S
authors.lastname: Michel
mesh_terms: D000818:Animals; D021081:Chronobiology Disorders / Q000473:pathology* / Q000503:physiopathology*; D002940:Circadian Rhythm / Q000502:physiology*; D006801:Humans; D009415:Nerve Net / Q000502:physiology*; D009473:Neuronal Plasticity / Q000502:physiology; D017711:Nonlinear Dynamics; D010507:Periodicity; D017440:Photoperiod; D013493:Suprachiasmatic Nucleus / Q000502:physiology*