Around the same time, references to a first and second sleep start to disappear. So, if you are one of those people who find themselves wide awake in the middle of the night and toss and turn ...

A few hours later they would wake up from their first slumber for between one to two hours, before going back for their second sleep, which would last until the morning. During night time waking ...

By comparing participants' first and second sleep studies, researchers discovered a link between each percentage point ...

The risk of getting dementia may go up as you get older if you don't get enough slow-wave sleep. Over-60s are 27 percent more likely to develop dementia if they lose just 1 percent of this deep ...