The two-sleep night once fit dark, quiet evenings, but bright lights and fixed schedules trained bodies to sleep in one block now.

Add Yahoo as a preferred source to see more of our stories on Google. Less than half of people who've survived a stroke will go on to have a healthy, normal sleep pattern, new research shows. Photo by ...

Less than half of people who've survived a stroke will go on to have a healthy, normal sleep pattern, new research shows. Normal sleep is defined as six to eight hours of shuteye nightly. However, a ...