Non-24-hour sleep-wake disorder (N24SWD) occurs when your sleep-wake cycle gradually shifts out of sync with the 24-hour day. It affects about half of blind people, but it can also affect those with ...

Advanced sleep phase disorder is a rare condition that causes your natural circadian rhythm, or sleep-wake cycle, to occur earlier than typical. As humans, our sleep-wake cycle— also known as our ...

Circadian rhythm sleep-wake disorders are a group of conditions in which the timing of an individual’s sleep is disrupted. Circadian rhythms are often referred to as the body’s internal clock or our ...

A new study finds that sleep timing is linked to dementia risk, as people with weak circadian rhythms face a 2.5 times higher ...

Past age 50, men are much more likely to have REM sleep behavior disorder than women. Jose Luis Pelaez/Stone via Getty Images Every night, you go through four to five sleep cycles. Each cycle, lasting ...

A person’s symptoms may vary depending on the sleep disorder affecting them. People may have difficulty falling asleep or experience low quality, disrupted sleep. The amount of sleep someone needs ...

A circadian rhythm is a natural process that regulates your body's sleep and wake patterns, among other key functions. It's often described as an internal clock that operates on a roughly 24-hour ...

YOU HAVE TO SLEEP AT THE RIGHT TIME. MINDY: IT IS VERY HARDWIRED. WE FOUND OUT THAT EVERYTHING SLEEPS AND EVERYTHING HAS A CIRCADIAN RHYTHM TOO. IT’S AN INTERNAL CLOCK. OUR BODIES ARE HARD-WIRED BY ...

Experts agree that seven to nine hours of sleep is ideal for most adults — but when it comes to your health, the total number of hours might not be the most important factor. In a major new study led ...