Cognitive asymmetries after waking from REM and NONREM sleep: effects of delayed testing and handedness

[Functions of paradoxical sleep and ontogenesis]

The hypotheses directly linked to cognitive and neurologic ontogenic processes ie consolidation of memory and learning, the maturation hypothesis of Roffwarg and the hypothesis of endogenous genetic programming of Jouvet, are analysed. The discussion of these theories are based on the analysis of: the neurophysiologic mechanism of REM sleep and its ontogenesis in human, the results of REM sleep deprivation in young animals and by a personal study of facial mimics during sleep in neonates. Active sleep could be assimilated, very early during ontogenesis, to REM sleep, it probably plays an important role in brain maturation during early development but the stimulation is probably, at this time, not very specific, later it could be a link between genetic programming and epigenetic processes.

Differential effects of awakening from REM and NONREM sleep on dichotic listening performance as a function of handedness

Fourteen right-handed and fourteen left-handed males were wakened from REM and NONREM sleep and tested on the dichotic listening test with verbal stimuli. For right-handers there was a significant right ear advantage (REA) only after REM wakenings, which was equal in magnitude to the REA obtained during waking. Left-handers showed significant REA after both wakening conditions, as well as during waking. These results are interpreted in view of the data suggesting REM-related right hemisphere activation and the role of the right hemisphere in regulating bihemispheric arousal levels.