A CPAP machine is used to treat apnea during this process, and muscle  paralysis often occurs during the (*) REM form of this process.
Some scholars believe this bodily process was once "segmented" between "first" and   "second" stages. A CPAP machine is used to treat apnea during this process, and muscle  paralysis often occurs during the (*) REM form of this process. Circadian rhythm regulates the  cycle of this process, a lack of which is called insomnia. For 10 points, name this process which is  recommended to last eight to 10 hours.
Some scholars believe this bodily process was once "segmented" between "first" and   "second" stages.
sleep