Early postnatal development of wakefulness-sleep cycle and neuronal responsiveness: A multiunit activity study on freely moving newborn rat

摘要: Abstract The development of the wakefulness-sleep cycle and neuronal responsiveness was studied on freely moving 1-, 3-, 5- 7-day-old rats. Semimicroelectrodes were implanted under ether anaesthesia for multiunit activity (MUA) recording from mesencephalic reticular formation (MRF) basal forebrain area (FB). Following recovery surgery between sessions pups put back to nest be fed by their mothers. In a temperature-controlled environment continuous MUA records made 16:00–18:00 19:00–21:00 h. MRF FB high during wakefulness, it decreased stable low level in quiet sleep appeared reach highest values paradoxical sleep. Neurone populations responded somatosensory (air puffs), visual (flicker) acoustic (1100 Hz) stimulation significant increase first day life. rate increased postnatal week; however, responses different stimuli exhibited developmental time-courses. A each stimulus characteristic units. This neonatal ‘supersensitivity’ tended decrease with age time-course changes proved modality-dependent.