[Temporal organization of sleep cycles in infants over 24-hour periods].

11 infants aged between 2 weeks and 6 months were continuously recorded for 24 h using polygraphic techniques. The duration of the sleep cycles and the proportion of quiet sleep and of paradoxical sleep within each cycle have been evaluated as a function of age and time during the nychthemeron. The duration of the cycles during the day-time in the older infants is shorter than the duration of the cycles during the night-time and the duration of both day-time and night-time cycles in the young infants. No differences at any age have been found among different parts of the night-time recording. The proportion of quiet sleep and paradoxical sleep within the cycle is different as a function of age but not as a function of duration of the cycle. Age does not affect the QS/PS proportion and the duration of the cycle in the same way.