EFFECTS OF ACUTE SLEEP-DEPRIVATION ON CONTROL OF THE DIAPHRAGM DURINGREM-SLEEP IN CATS

Recently, investigators demonstrated that acute sleep deprivation in h ealthy subjects results in significant periodic decrements in ventilat ion during recovery rapid-eye-movement (REM) sleep. The neural bases o f such phenomena are unknown. The decrements in ventilation coincide w ith REM sleep-associated phasic activities, such as bursts of eye move ments. The purpose of this study was to determine the effects of acute sleep deprivation on control of diaphragm activity during recovery RE M sleep. In chronically implanted, naturally sleeping, unrestrained ca ts, we recorded the electroencephalogram, electrooculogram, pontogenic ulooccipital waves, neck and diaphragmatic electromyograms, and the co mputed moving average of the diaphragm. Acute sleep deprivation result ed in an increase in REM sleep-associated phasic alterations in diaphr agmatic control during recovery REM sleep. There was an increase in th e percentage of bursts during recovery REM sleep with reduced inspirat ory drive. Acute sleep deprivation resulted in a substantial increase in the number of brief pauses (fractionations) in diaphragmatic activi ty during recovery REM sleep. Respiratory timing was also affected by sleep deprivation, with a reduced expiratory time resulting in an incr eased duty cycle ratio. There was a significant increase in the percen tage of bursts with decremented peak amplitude of the moving average o f the diaphragm, a measure that correlates with tidal volume. Despite significant increases in respiratory-related phasic alterations, there were no parallel increases in excitatory phenomena, i.e., eye movemen ts or pontogeniculooccipital waves. These results imply that respirato ry control mechanisms in REM sleep are sensitive to the effects of pri or sleep deprivation.