Nocturnal sleep organization during the first months of life.
42 healthy infants (18 boys and 24 girls) aged 4-30 weeks had polygraphic whole night recordings. Four sleep stages were identified, using standard sleep scoring parameters: intervening wakefulness (W), quiet sleep (QS), active sleep (AS) and transitional sleep (TS). Our results show, first, an important decrease of the intervening wakefulness between 4-5 weeks and 6-7 weeks, then a modification of the distribution of this intervening wakefulness after 21-22 weeks. QS increases significantly from 4-5 weeks to 27-30 weeks with a linear distribution throughout the night. The QS modifications seem related to the appearance of sleep spindles between 6 and 11 weeks. Intervening wakefulness and quiet sleep changes appear simultaneously with the emergence of the circadian rhythm. Active sleep and transitional sleep remain stable from 4-5 weeks to 30 weeks. Furthermore, no change in the internal organization is observed for active sleep during this period.
D000367:Age Factors; D002940:Circadian Rhythm; D004569:Electroencephalography; D004576:Electromyography; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D012890:Sleep / Q000502:physiology*; D012894:Sleep Stages / Q000502:physiology; D014851:Wakefulness / Q000502:physiology