AdvertisementI usually wake up just ahead of my alarm. What's up with that?04:48Download AudioResumeDecember 26, 2022Will StonefacebookEmailHumans have an elegant and intricate system of internal processes that help our bodies keep time, with exposure to sunlight, caffeine and meal timing all playing a role. But that doesn't account for "precision waking." (Sarah Mosquera/NPR)
