Carotid Blood Flow During REM Sleep

Abstract

A conspicuous decrease in common carotid blood flow is a constant feature of REM sleep in rabbits during several months of recording. This decrease is the result of a marked depression of both peak flow and heart rate. In spite of the unstable systemic hemodynamic conditions revealed by this study, several independent functional and morphologic factors concur to increase the vertebral blood supply to the brain during REM sleep. This increase raises preoptic-hypothalamic temperature, since vertebral artery blood is warmer than carotid artery blood.