[The study of sleep in full term and preterm neonates with EEG polygraphy].

We accomplished polygraphies in two groups of infants: 1) preterm infants born before 33 weeks CA, and recorded between 33 and 48 weeks CA; 2) full term infants, recorded between 39 and 48 weeks CA. We compared in each group of infants: 1) the development of behavioral states organization; 2) the maturation of cortical bioelectric activities; 3) the development of concordance between behavioral states and EEG pattern; 4) sequences of behavioral states and EEG pattern when the babies fall asleep. In all the aspects considered, we describe some developmental changes, to understand how, through these changes, the newborn sleep-wake ultradian cycle is replaced by 24 hr-cycle, typical of the infantile period. This basic process is expression of maturation of the central nervous system because it is related to CA and not to extrauterine experience. The EEG-polygraph usually used in clinical practice allow us to follow these extraordinary transformations very closely.