Sleep cyclicity in infants during the earliest postnatal weeks.
Cyclicity within sleep was investigated in 20 fullterm infants who were monitored in the home for 24-hour periods when they were 2-5 weeks old. Using a pressure sensitive mattress in the crib, analog signals from the baby's respiration and body movements were computer scored for: Quiet Sleep, Active Sleep, Active-Quiet Transitional Sleep, Sleep-Wake Transition, and Wakefulness. Sleep episodes with at least four recurrences of Quiet Sleep were analyzed for cyclicity. Significant cyclicity of Quiet Sleep was found in 49 of the 55 sleep episodes analyzed. The mean Quiet Sleep recurrence period was 63.2 minutes. Eighteen of the 20 infants exhibited cyclicity on one or more weeks. Thus, sleep during the neonatal period is generally characterized by the presence of cyclicity. Cyclicity was not related to other parameters of the sleep cycle, but was correlated with stability of state patterning over weeks. The results provide new evidence for neurobehavioral competence of the neonate in terms of sleep organization.
Thoman
E B
EB
Department of Psychology, University of Connecticut, Storrs 06268.
McDowell
K
K
D000375:Aging / Q000502:physiology*; D000818:Animals; D000831:Animals, Newborn / Q000502:physiology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D010507:Periodicity; D012890:Sleep / Q000502:physiology*