"There are historical records of people sleeping in two bouts at night," Wehr explains. "They called the first bout dead sleep, and the second bout was called morning sleep. The wakeful period in between was referred to as watch or watching.”
In one study that simulated the long winter nights that people would have experienced in the days before artificial lighting, Wehr points out, subjects ended up sleeping in two stints separated by a two-hour period of wakefulness, a “quiescent, meditative state” that some called “midnight comfort.”
I’ll try to keep this bit of soothing news in mind next time I'm up in the middle of the night. Because if anxiety contributes to insomnia, one of the things I end worrying about most at 2 a.m. is that I’m not getting enough sleep.
The piece goes on to say that such wakefulness is not uncommon. especially as we age and our sleep becomes more fragile. In other words, there’s nothing wrong with me--I’m just getting old.