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 ...

REM may be the most talked-about part of the sleep cycle, but getting enough of it can still be an elusive quest. You might know by now that it’s important, but maybe you don’t know exactly why or how ...

There are tell-tale signs when you don’t get enough REM sleep. It’s the fourth stage of sleep and it’s crucial for processing ...

REM stands for rapid eye movement — a stage in the sleep cycle when your brain is almost as active as when you’re awake. Getting enough REM sleep is crucial, as it helps you store information and ...

Researchers trace how different sleep stages may fine-tune what we remember, trading specifics for more general knowledge. When you purchase through links on our site, we may earn an affiliate ...

Scientists have recently shown that both the quality and the amount of sleep we get may influence our risk of developing Alzheimer’s disease. Now, a study suggests that people who take significantly ...

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 ...

Sleep is often treated as downtime, a passive break between the real business of being awake. But a new study has revealed that sleep is active, essential biology, showing how the brain uses the night ...

Taking too long to enter the phase of sleep in which we dream may be an early sign of Alzheimer's disease. This is the conclusion of an international team of researchers who studied the sleep patterns ...