CarbonNYC via Flickr / Creative Commons
Sleep patterns and depression have been linked to the neurotransmitter hypocretin.
It sure would be wonderful if someone came along and said, "You don't have to get 7 to 8 hours of sleep to be healthy, just stop feeling so guilty!"
Matthew J. Wolf-Meyer is the author of "The Slumbering Masses: Sleep, Medicine, and Modern American Life."
He's here to tell us that our modern ideas about sleep habits have less to do with health and medicine and more to do with social norms and historical trends.