> This doesn't depend on the age. Though it might depend on a person. Yeah, definitely by person, because personally it seems to have only happened as I got ol

> This doesn't depend on the age. Though it might depend on a person. Yeah, definitely by person, because personally it seems to have only happened as I got older. From birth until I was ~30 or so I could sleep through alarms unless strategically placed away from my bed, and if not awoken, I slept until ~2-3 pm, no matter when I went to bed. Nowadays, I can go to bed at any time and automatically wake up when needed, no matter how tired I'm "supposed" to be. Neither my habits nor much in my life has changed since I was 25 or so, so guessing it has to do with age, but in reality, who knows why?