Section I:The Influence of Sleep and Anesthesia

Abstract

The respiratory system mediates a vital relationship between le milieu exterieur and le milieu interieur of the organism.The control of this system’s behavior has been studied in biologically contrasting conditions such as rest––exercise, health––disease in order to gain deeper insight into the mechanisms involved in its control. Recently much attention has been directed toward a third contrasting condition: consciousness--unconsciousness. Two common forms of unconsciousness are sleep and anesthesia. The present group of investigators examines the effect of these conditions in humans and animals, adults and infants, on mechanical components and neuromuscular components. At the cellular level Hugelin shows that the respiration related units which form a continuous column of cells from the medulla to the medial thalamus have different sensitivities to barbiturates. The activity of some respiratory regions actually increases during anesthesia. Bianchi and Barillot report that chloralose anesthesia strongly enhances both insp iratory and exp iratory durat ions but not their ratio. The majority of inspiratory bulbo-spinal neurones and expiratory bulbo-spinal neurones change their firing pattern under anesthesia. This proved to be true also for inspiratory and expiratory laryngeal motoneurons.