A wearable tracker can’t always tell the whole story of how well you slept the night before. Here's what "core sleep" is and ...

In the morning, I open my smartwatch's sleep log.I thought I slept for 7 hours last night, but my REM sleep was short. The ...

While it is certainly true that rapid eye movement (REM) sleep functions, in part, to promote a healthy waking mind, there are compelling reasons to believe that the opposite is the case as well: the ...

Nearly 100,000 people wore wrist sensors for a week, and one stage of sleep stood out from all the others.

Sleep has two phases: non-rapid eye movement (NREM) and rapid eye movement (REM). It also has four stages that repeat in 4 to 6 cycles nightly. Each stage affects your body differently, from light ...

Eugene Aserinsky never wanted to study sleep. He tried being a social worker, a dental student, and even did a stint in the army as an explosives handler. He enrolled at the University of Chicago to ...

A 2021 phone poll revealed that only 34% of Americans "sometimes" remember their dreams. About 1 in 10 say they "almost always" can, and the same percentage say they "never" do. Explanations for such ...

An extra 47.6 minutes of REM sleep, the spread between the typical low-REM and high-REM sleeper in the UK Biobank, goes with a 26 percent lower hazard of heart failure and a 46 percent lower hazard of ...

If you wake up during or just after a REM period, you are more likely to remember what you were dreaming. Most of the dreams one remembers are the ones they see with their eyes open. When asleep, most ...

Accidentally kicking your partner or falling out of bed in the middle of the night might seem like something to laugh about in the morning. But dramatic sleep movements might actually be a sign of a ...