We used to sleep twice each night
delanceyplace.com
delanceyplace.com
I've no doubt that we're not sleeping optimally at the moment with all the artificial light and impositions on our time, but at the same time not everyone sleeps the same way, and just because we sleep differently to how we would naturally do it, doesn't necessarily mean it's worse.
Personally I run best with a good 8-9 hour sleep and a quick 20 minute power nap in the mid afternoon, but other people I know find that more than 6-7 hours sleep exhausts them, or other people who can't stand naps.
I think the best takeaway from this article is that we definitely need better sleep research.
It is harder to check a book's bibliography, though. Sometimes the cited paper isn't publicly available, or sometimes the author cites a book you don't have (often their own books), and really in this day and age it's a little bit much to ask your audience to make a trip to the library just to check if an author isn't taking an extreme artistic license or even just making shit up.
I got a bit disillusioned after this tale. And definitely a lot more skeptical about "these types of book", you know the kind that weaves a lovely narrative "supported" by actual (pop) science research. The juicier the anecdotes, the more skeptical you should be.
And apparently this is still a pitfall even if the general premise of the book is right! (the core idea behind Black Swan I pretty much agree with--it just happens so that the very first reference I picked at random to check, turned out to be full of shit)
[0] One of Taleb's previous works, Fooled by Randomness, is roughly about the same topic, but goes into (a little bit) more technical detail. I enjoyed it a lot better. Also, it doesn't feel the need to make a stab at the French every third page or so (something that really puzzled me in Black Swan, maybe it was an in-joke between him and Mandelbrot?).
I also check references sometimes, mostly when narrative is unexpected or unconventional. Often the superficially striking theory quickly falls apart when the references from sources cited are either taken out of context or distorted to author's liking.
Yes, frequently. I'm not endorsing this particular book but I find the assertion quite plausible because I was familiar with the history of monastic prayer schedules that included getting up in the middle of the night.
really in this day and age it's a little bit much to ask your audience to make a trip to the library
I like going to the library myself, and with access to so many reference books online I find it easier than ever to check things. I can't help feeling that you're projecting your disappointment with Taleb's book onto this one.
http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2869.1992....
2) The study looked at 10 hrs daylight vs 16 hours of daylight. I wonder if "bi-phasic" sleep isn't just a quirk since the current consensus is humans need 7-9 hours of sleep a day. So, when you have less daylight - instead of sleeping continuously for 14 hours of night, you wake up at some point in between. The body simply does not need 14 hours of sleep per day.
If this were true - and referencing the paul graham-ism about meetings breaking up the day into segments too small to be useful - it is possible that artificial light allows us to compress the night hours such that they fit our maximum need for sleep, and also give us larger continuous blocks of time to use during the day. from this perspective, artificial light supports human evolution by making us more efficient (rather than representing some undiscovered health problem).
3) Also interesting to consider how the northern-most europeans would have adapted, given extended daylight for months at a time.
4) lastly - it's awesome to see we are getting health advice from medieval times. During the same period, people commonly drank alcohol almost 100% of their waking hours. Alcohol certainly affects my quality of sleep and duration. On a related note - a study of the effect of continuous alcohol consumption on judgment might explain a lot of the wacky behavior back then.
Will a sufficient amount anecdotal evidence turn into proof?
In any case, I was getting worried that too much coding had destroyed my health, it turns out I am may have gone back to sanity instead; the article certainly made my day.
In general I'd wish if people were more careful with general pronouncements like this — just because some people somewhere did something (say, hunt by running, eat only meat, eat only berries, sleep in two parts, sleep with the head hanging down, bake crackers, not cook anything, whatever) doesn't mean all humans did that until 5 years ago, nor does it mean it's a somehow best course for every single human dead or alive. Now, that it may be a good idea to try out (depending on specific idea, with specialist supervision maybe), but it might turn out horrible.
And I doubt anything like "optimal" sleep even exists, unless you start including additional conditions. You need work, you have to balance the need to sleep with the requirements of it (and some enjoyable jobs do start early), you might even a tendency to sleep too long for own comfort unless kept in check, and if you have apnea sleeping longer will only make things worse.
So, my annoyance here is mostly with the generalization made by the statement — not "we". Some other people, at some point in history, did, and wrote down all the awesome experiences they had while doing it.
Lately I find that my sleep is segmented; I was wondering if it's a bad thing. I generally sleep from 3am to 8am or so, and then I wake up, eat an apple, and read the Internet. And then I sleep from 9am to 11am again. It's been pretty consistent for awhile. It seems to be the pattern of 2 REM cycles and then 1, since I believe people generally get 3 in a night.
It's perhaps not the same thing, since it seems unrelated to daylight. It may be related to information retention. I generally wake up and write some notes about what I thought about during my sleep (lately I find that my dreams are almost like thinking). And then I do some googling related to those topics. And then I go back to sleep and retain it.
Another thing that's interesting about sleep is that humans have a dimorphism between early birds and night owls. I read a hypothesis that it's because it maintains the property that some members of a group are a awake at all times, e.g. to guard against predators and so forth.
Back at home, I go to sleep around 12 or 1am.
I should probably live somewhere like that with less reliance on artificial light. I felt so much better being able to just go to sleep and pass out pretty much immediately, and actually felt refreshed and ready to face the day in the morning. That said, I rather appreciate the comforts of highly developed countries…
Our circadian rhythms are regulated by sunlight. More specifically, the pineal gland in the brain suppresses melatonin when the retina is exposed to natural sunlight. This allows for a huge melatonin surge at night, putting you to sleep and telling the body to perform its nighttime functions. When you aren't exposed to natural light during the day, your pineal brands produce melatonin when they should not be doing so, leading to all sorts of problems.
To make matters worse, even looking at the sun through a window won't work; enough spectrum is blocked that melatonin production continues.
tl;dr; If you want to optimize health and sleep, work outside (in the shade) as often as possible.
I've noticed that I just do more when the longer days return...
1. Warm thanks to f.lux.
I found the late night period very relaxing, and productive if I decided to read or write something. I found an article similar to this one around that time, and thought "Aha! That explains it!"
Unfortunately, my family has come to join me here, and I've made a lot of new friends, and I'm definitely not going to sleep at 8 pm anymore. So the phenomena has ended. I kind of miss it!
Also, if babies naturally are biphasic sleepers (not saying they are not, just that they're not naturally as disruptive as modern practices make them), that supports humans being naturally biphasic but suppressing it through habits and environments.
When it got dark - we went to sleep. And then we got up at 6:45sh to go catch the bus to school. I don't ever recall a "second sleep" or waking up after I fell asleep.
Maybe this doesn't apply to teenagers.
The myth of the eight-hour sleep
I'll wake up for a couple of hours every now and again and just read and walk around the house and do things. In the morning, I always feel rested.
The hour or two you get is literally between sleep cycles. During that nighttime, my mind would race and worry about the most useless things. The dreamlike state wouldn’t shut off cleanly and I could not concentrate, so that hour was never productive like I usually am during the night hours. It was impossible to learn anything, nothing would be retained. The second sleep cycle was always turbulent and I found myself waking up several times throughout. During the day, it felt like my emotions were muddled, like I was an automaton. That hour or two morphed into my only personal time, and the day became mindless, numb.
I considered this a failed experiment and re-trained myself back to a single sleep cycle. It was harder going back than it had been to split in the first place. After several months of ‘normal’ sleep I was back to having deep peaceful sleep. I was myself again during the day. I could learn and keep knowledge. The world was interesting again and I was engaging with it.
These were my experiences and expect it would be different for each individual.
Never specifically asked or looked for it, but never heard anything about it either.
I just chalked it up to more hours in bed and being really REALLY tired when going to bed, but it makes total sense that the lack of artificial light played a big part.
Is taking a nap then "going to bed" later basically the same thing as a 2 sleep night?
I think naps are a good modern example of a 2 sleep night. I wonder when people began napping? The Google Ngram Viewer makes me think we've been napping for years [1], except perhaps right after WW2, but then 1970 happened and we started getting tired. :)
[1] http://books.google.com/ngrams/graph?content=nap&year_st...
I have also included napping and siesta in the plot. These have a fairly constant use.
http://books.google.com/ngrams/graph?content=nap%2Cnapping%2...
"You must sleep some time between lunch and dinner, and no half-way measures. Take off your clothes and get into bed. That's what I always do. Don't think you will be doing less work because you sleep during the day. That's a foolish notion held by people who have no imagination. You will be able to accomplish more. You get two days in one-well, at least one and a half, I'm sure. When the war started, I had to sleep during the day because that was the only way I could cope with my responsibilities."
That a subject that never cease to amaze me. Civilizations rises and fall and with them knowledge. To me, Dan Simmons kind of use that in Ilium and Olympos as background. What will happen when our digital civilisation falls ?
This is why messages for nuclear waste disposal sites are meant to transcend not only modern media, but also modern language.
http://en.wikipedia.org/wiki/Waste_Isolation_Pilot_Plant#Mes...
This is a real problem for historians: unusual occurrences are usually well-documented in permanent media; everyday life usually is not.
I've recently applied this same philosophy to eating. I eat when I'm hungry and I stop eating when I am no longer hungry (not when I'm "full").
The most important takeaway- as always, "optimum" only has meaning in the context of what exactly you hope to optimize for.
A nitpick, but I don't think this has been true for many decades. There are lights on tractors, you know. True, daylight is a better time for many farming activities, but during harvest, my father will sometimes work from 6am-2am if the conditions are good. (Yes, 20 hours though a nap after lunch is possible if there is someone else around to run the combine during that time).
BTW I don't have any evidence or bias against this. I'm just genuinely curious and a bit confused.
Very recently, I started taking 3-6 mg of melatonin about thirty minutes before going to bed. I find that I fall asleep more more quickly, but I inevitably awake roughly four to five hours later, completely lucid. After a few minutes of being awake, I roll over and easily fall asleep again for another three to four hours. When the morning comes, I wake up feeling much more refreshed than I did when I slept continuously throughout the night.
I usually spend long nights in front of my computer, and from what I have read, melatonin production is reduced by the presence of blue light. I have started using Flux in addition to my melatonin intake. I can only guess that I am starting to enter a more "normal" sleep cycle.
Might want to change this.
http://webcache.googleusercontent.com/search?q=cache:IAiep0K...
(east coasters were already in their second sleep by the time it was posted)
[1] http://www.amazon.com/At-Days-Close-Night-Times/dp/039332901...
It was a great routine. Ever since career and family became part of my life, I've rarely ever had such peaceful moments in my life.
It seems to me A. Roger Ekirch (a historian) used confusing text to create a medical theory then popularised it.
There is little to no one else saying it's true but somehow it's being spread as fact.
Equally it's interesting no one is refuting it. It's a popular theory I've heard a lot of people mention. If it is hogwash why is the medial community not jumping in and saying there is no evidence of this?
Another interesting pattern is that I can't go to sleep after midnight. I have to be really tired to start sleeping between 00 and 01. 21-00 is all good, also after 1 or 2 I can start sleeping easily
Well, I think I will give my new sleeping pattern a chance