REM sleep goes even deeper into brain recovery, dreaming and processing memories and emotions. This is the sleep stage in which your eyes move rapidly. If you've ever caught your dog or cat in a REM ...

A good night’s sleep isn’t just about the number of hours you log. Getting quality sleep — the kind that leaves you feeling ...

When in doubt, ask an expert. Dr. Michael Breus, PhD, simplifies and differentiates REM sleep vs. deep sleep for us. REM ...

On an Apple Watch, "core sleep" is another name for light sleep, which scientists also call stages N1-N2. It is not a type of deep sleep, and has no relation to REM. But in the scientific ...

In the stillness of the night, when the body should lie calm in sleep, something else may be happening beneath the surface.