Yes, other stages are important. But during polyphasic sleeping, which is when you sleep more than once in a day, your sleep stages can get split too. We even h

Yes, other stages are important. But during polyphasic sleeping, which is when you sleep more than once in a day, your sleep stages can get split too. We even have some scientific evidence for it. Though we still don't understand it well. More within links here: http://qz.com/430415 http://qz.com/430415.