Sleep disorders, such as sleep apnea or restless leg syndrome, can also cause people to wake up during the night. “Disruption of the body’s natural sleep-wake cycle” can also lead to ...

In a nutshell, wake windows are the period of time between your child's sleep periods—i.e., the times that your baby is awake. “Wake windows refer to the amount of time a child’s brain can ...

The biologists were interested in flies that have a deregulated sleep-wake cycle and whose particular area of the brain, called ‘mushroom bodies’ because of its characteristic shape, is damaged.

Her biological sleep-wake cycle, or circadian rhythm, is out of sync with the demands of the modern world. My friend, who asked to remain anonymous, has always been an early riser, even as a teenager.