[Blood circulation and energy metabolism of the brain in healthy sleep].

Studies on sleep-related changes of cerebral blood flow (CBF) and cerebral metabolic rate (CMR) provide important information about sleep as an active neurophysiological process. Decreases in global values of CBF and CMR during non-rapid-eye-movement sleep illustrate rate role of this sleep period as a quiescent phase for the human brain. Increases in CBF and CMR and fast alterations in cerebral perfusion during rapid-eye-movement sleep are indicative of an active state with labile regulation. Local changes in CBF and CMR characterize the heterogeneity of the underlying physiological regulation. The dynamic feature of cerebral perfusion in relation to electroencephalographic patterns obtained by new recording techniques reflects quantitative uncoupling between cerebral electrical activity and cerebral perfusion during parts of the sleep period. A critical analysis of the current literature and history of sleep research on this topic is presented.