Developmental Changes in Sleep Spindle Characteristics and Sigma Power across Early Childhood.
Sleep spindles, a prominent feature of the non-rapid eye movement (NREM) sleep electroencephalogram (EEG), are linked to cognitive abilities. Early childhood is a time of rapid cognitive and neurophysiological maturation; however, little is known about developmental changes in sleep spindles. In this study, we longitudinally examined trajectories of multiple sleep spindle characteristics (i.e., spindle duration, frequency, integrated spindle amplitude, and density) and power in the sigma frequency range (10-16 Hz) across ages 2, 3, and 5 years (n = 8; 3 males). At each time point, nocturnal sleep EEG was recorded in-home after 13-h of prior wakefulness. Spindle duration, integrated spindle amplitude, and sigma power increased with age across all EEG derivations (C3A2, C4A1, O2A1, and O1A2; all ps < 0.05). We also found a developmental decrease in mean spindle frequency (p < 0.05) but no change in spindle density with increasing age. Thus, sleep spindles increased in duration and amplitude but decreased in frequency across early childhood. Our data characterize early developmental changes in sleep spindles, which may advance understanding of thalamocortical brain connectivity and associated lifelong disease processes. These findings also provide unique insights into spindle ontogenesis in early childhood and may help identify electrophysiological features related to healthy and aberrant brain maturation.
Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO 80309, USA.
Ian J
IJ
McClain
Child Development Center, University Children's Hospital Zurich, 8032 Zurich, Switzerland; Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
Caroline
C
Lustenberger
Institute of Pharmacology and Toxicology, University of Zurich, 8057 Zurich, Switzerland.
Peter
P
Achermann
Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO 80309, USA.
Jonathan M
JM
Lassonde
Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO 80309, USA.
Salome
S
Kurth
Department of Integrative Physiology, University of Colorado Boulder, Boulder, CO 80309, USA.
Monique K
MK
LeBourgeois
D001921:Brain / Q000502:physiology*; D058256:Brain Waves / Q000502:physiology*; D002657:Child Development / Q000502:physiology*; D002675:Child, Preschool; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D012890:Sleep / Q000502:physiology*; D012894:Sleep Stages / Q000502:physiology; D014851:Wakefulness / Q000502:physiology