The line that huanted me: “On average, a person in his 70s has about one hour less sleep per night than a person in his 20s".<p>Since my son was born I average about 4 hours of sleep a night. I actually seem more high functioning on 2 hours than on the rare occasion I get 8 (I joke that my body assumes I'm dead and starts giving up).<p>I have embraced one thing, something I never understood as a child, falling asleep on the couch. I get my best sleep between the time my wife puts a boring movie on and when she tells me to go to bed.
tl;dr - a neural basis for insomnia: "The new findings demonstrate for the first time that a group of inhibitory neurons are substantially diminished among the elderly and individuals with Alzheimer’s disease."<p>Lack of the inhibitory neurons may prevent the brain from entering and maintaining sleep states.
I've noticed that a lot of people, including myself, don't suffer from insomnia with age, but the ability to sleep deeply for 7 to 8 hours. Nowadays, I average 6 hours of decent sleep, but, no matter how rested (or lack thereof), I get up and feel like crap throughout the day. I have NO problems, though, with falling asleep.