Time course of EEG background activity level before spontaneous awakening in the second semester of human life.

This research aimed at investigating the time course of the EEG background activity level before spontaneous awakening out of rapid eye movement (REM) sleep, and non-rapid eye movement sleep with and without slow wave sleep (NREMSWS+, NREMSWS-) in the second semester of life. Twelve infants from 25 to 54 weeks of life were continuously monitored by polygraphic recording and behavioural observation during the night, and the EEG activity was analyzed by a method of automatic analysis. The EEG activation level increased before the awakening out of NREMSWS+ sleep, and was always high both in REM sleep and in NREMSWS-.