[Waking and sleeping E.E.G. in normal babies before 6 months of age (author's transl)].

In 44 children aged from 1 week to 6 months, 70 polygraph records were performed. The day tracings were carried out in the nursery in the child's normal environment. They lasted from 1 to 3 sleep cycles. As well as classical EEG developmental data, some new or rarely described in the literature data are pointed out. The onset of sleep is frequently difficult to define precisely. EEG slowing sometimes begin the eye open. Up to 12 weeks, the mode of onset of sleep (defined by the sole criterion of rapide eye movements) is variable: some babies fall asleep in active (AS), the other in quiet sleep (QS). After 12 weeks of age, all children fall asleep in quiet sleep. The early appearance on the median line of the fiqures characteristic of stages of maturity is striking. Vertex sharp waves and spindles appear in QS from 3 weeks with marked interindividual variation. The rhythmic vertex-occipital sharp figures ("saw-tooth" waves) of AS appear after 5 weeks and become well defined from 11 weeks. Several weeks later these characteristic figures spread to the central and posterior areas of the two hemispheres. Quiet sleep and active sleep in babies before 6 months of age are not similar to the slow wave and paradoxical sleep of the adult. Some behavioural parameters, such as body and eye movements permit to oppose the 2 states of sleep as they do in adult. On the contrary, the EEG morphology and certain other variables present some differences compared to the adult.