You all know the stereotype of old (or even middle aged) people going to sleep at 7 pm. Webcomic writer Scott Kurtz certainly experiences it:
I am currently very much a night owl, someone who sleeps in late and stays up late. Is it inevitable that I’ll lose that as I grow older? Perhaps work will force me out of it regardless of age, but what if I were self-employed for the rest of my life? Would that make a difference? And what do you think of the grandfather’s proverb in general?
I’m 65; note the time at which I posted this.
Wow! 8:05PM 
Of course, that’s my local time which is GMT+10, so for all I know it’s 9 o’clock in the morning where you are 
I think that 4:05 am could go either way. I always say that the only thing that true night owls and early birds can agree on is that 4:00 am is a great time to be awake.
My mother-in-law is 71, and if she’s asleep before midnight, she’s probably ill. She still claims to get her most productive work done after midnight, in fact. (Especially in the summer, when it’s light all night and she’s been known to be working in her garden at 2 a.m…) I suspect there’s some tendency towards becoming less of a night owl as we age, but those who are naturally strongly late-night folks aren’t going to become morning people just because a few dozen birthdays have passed.
I just turned 60, work at home, and have developed a strange sleep pattern. I’m usually up until 2-3 am, sleep about 4-5 hours, am up until late morning, then get a few hours more sleep into early afternoon.
My mental alertness during my morning awake period is maybe 85%. My brain doesn’t function optimally until I get up in the early afternoon.
I know a pair of night owls who are 61 and 62. They usually fall asleep around 6 in the morning.
When I was a kid, my best friend’s granny would catch a nap at about 9:30 pm, get up at 11:00 pm, and stay up until about 5:00am reading and watching television. Then she’d sleep for another 3 or 4 hours.
I’m 47 and was up until around 1:00 last night playing WoW (and thereby breaking two stereotypes!). Only reason I went to bed then was because of work this morning.
Actually, I think I need less sleep now than when I was younger. It used to be that if I stayed up half the night I would sleep til noon the next day. Now if I’m still in bed at 9am I’m sleeping late.
My grandmother rarely gets to bed before midnight, and is up before dawn every day.
Dern furriners.
Absolutely true.
I’m an elderly night owl.
Off and on.
It starts by accident, like just remembering at bedtime that you haven’t eaten yet, starting a pot of pasta, and picking up a book while you wait for it to boil.
Soon it is 3am and you are still reading.
It can be a week before you return to your normal bedtime.
Not impossible at all. I’m not *exactly * “elderly” yet, but in my couple of months’ unemployment I have joined my husband in a ridiculous pattern of going to sleep at 2 or 3 a.m. and sleeping until nearly noon.
It’s also often the case that even healthy older folks really don’t need as much sleep as a young person. A lot of “seniors” stay up half the night and then nap during the day.
My late father, before his health declined, used to go out dancing with a bunch of other oldsters (mostly “ladies”) several nights a week. He’d sleep in, and then also take a nap in the afternoon. This was a person who, during his working years, used to get up at the crack of dawn – 11 p.m. was reaaaaly late.
I once heard that we neded less sleep as we got older, however a Google search for a cite only showed that many thought this to be incorrect. However, my grandmother was able to live on only a few hours of sleep per evening all the time in her 90s (small sample size) and she was up late most every evening.
She did take a nap or two during the day, however…
I’ve always been a hardcore night owl. But I am seeing it change as I get older. Mostly that I wake up at a reasonable time no matter what. Like right now, I probably can’t sleep much later than 10 AM. I just get too tired to stay up past 1 AM, no matter how much I want to. This is still pretty night-owly, but I can see where the trend is. So for me, pretty impossible.
Age 62. I do most of my posting at SDMB in the middle of the night. It’s 4:18 a.m. now.
I’m 43, not exactly a senior citizen, but I keep weird hours, too. I usually fall asleep during the late, local news (around 11:30pm), and I’m up and doing things by 1:30 or 2am. I’m up the entire day, then catch an hour or so nap in the late afternoon.
I’m lucky I’m a houseleech and able to do it this way, I guess. When I was working, I had problems sleeping during the night, so I switched to the night shift, where I had no problems at all.
Our daughter, VeryAcetone, is still at home, and she’s 18, and we will sit up all night and play video/computer games or get some housework done. There’s never a shortage of things to do around here in the wee hours of the morning!
When Mr.Acetone is home on weekends (He’s an OTR truck driver), we still stay up all night, then sleep between 6am and 10am, still looking forward to that hour or so nap in the late afternoon!
My grandmother is 94, and stays up through the night watching tv and people-watching out of her front window (she lives in a city neighborhood full of popular restaurants and the occasional drug deal); I think it’s probably the most interesting time of day for her. She sleeps off and on through the morning/day. Part of this may be just that she has trouble sleeping for more than a few hours at a time. And she wonders why she feels tired all the time.