Temporal distribution of sleep states, somatic activity, and autonomic activity during the first half year of life.
Twelve-hour, all-night polygraphic recordings were obtained from 25 normal infants at 1 week and 1, 2, 3, 4, and 6 months of age. The objectives of the study were to provide a description of the emerging temporal distribution of quiet sleep (QS), active sleep (AS), and motility, and to describe the maturation of a circadian influence upon heart rates. With increasing age, increased percentages of AS began to cluster toward the end of the night and increased percentages of QS toward the beginning. A circadian influence upon heart rates was observed in AS and indeterminate sleep prior to its existence in QS. At 2 and 3 months of age motility in AS and QS increased linearly during the night.
D000367:Age Factors; D002940:Circadian Rhythm; D005247:Feeding Behavior; D005260:Female; D006339:Heart Rate; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009043:Motor Activity / Q000502:physiology; D012890:Sleep / Q000502:physiology*; D012894:Sleep Stages / Q000502:physiology; D014851:Wakefulness / Q000502:physiology