Deep sleep refers to slow-wave sleep — a stage in the sleep cycle when brain waves slow down. Getting enough deep sleep is crucial for numerous bodily functions. But how to increase deep sleep isn’t ...

Light sleep is the beginning of your sleep cycle and your body's way of winding down. Breathing, heart rate and muscle changes prepare your body for the deeper sleep to come. Light sleep is broken ...

A recent study published in the journal Nature Neuroscience reported that brain clearance is reduced during anesthesia and sleep. Sleep represents a state of vulnerable inactivity. Given the risks of ...

Few experiences rival the calm satisfaction of falling asleep easily and waking up feeling fully rested. But sleep is more than a luxury or idle downtime, it’s a vital biological process that supports ...

Deep sleep is one of the most essential stages of the sleep cycle, playing a vital role in how well you feel both physically and mentally. Often referred to as slow-wave sleep or delta sleep, this ...

Deep sleep helps you feel refreshed and typically makes up 20–25% of total sleep time, or about one to two hours per night for adults. If you're not sleeping soundly, certain strategies can help ...

Sign up for CNN’s Sleep, But Better newsletter series. Our seven-part guide has helpful hints to achieve better sleep. Need another reason to prioritize your sleep ...

Every day, some 60,000 patients enter a state more like coma than sleep when they undergo general anesthesia — according to an unsettling study published Dec. 30 in the New England Journal of Medicine ...