9 ms·

How Little Sleep Can You Get Away With?

229 points by robg 15y ago

IanMikutel 15y ago
"P.V.T. is tedious but simple if you’ve been sleeping well. It measures the sustained attention that is vital for pilots, truck drivers, astronauts. Attention is also key for focusing during long meetings; for reading a paragraph just once." I can't say how true that is when you're doing a ton of email all day or research, and its more a function of the sum total of small delays in re-reading that build up over the course of an entire day. Contrasted with a day when your mind is so clear that you require no re-reading, it feels like you are so much more productive. Additional sleep links: 1. Sleep: How to hack your brain (http://www.dustincurtis.com/sleep.html http://www.dustincurtis.com/sleep.html) 2. The 4-Hour Body: Engineering better sleep (http://techcocktail.com/book-preview-the-4-hour-body-engineering-better-sleep-2010-12 http://techcocktail.com/book-preview-the-4-hour-body-enginee...)
- scott_s 15y ago
  http://news.ycombinator.com/item?id=1464142 http://news.ycombinator.com/item?id=1464142
torstesu 15y ago
It would have been really interesting to see if power naps had any effect on the performance of the subjects that were deprived of sleep. My personal experience is that 15 minutes in the horizontal position improves my awareness and performance. An additional hack is to drink an espresso the moment before you take your power nap - the effect of the caffeine will kick in in about 15 minutes after consumption.
- petercooper 15y ago
  Or the "siesta" style of sleep generally. That is, the pattern of having a nap in the day and a shorter nighttime sleep.
  - michaelcampbell 15y ago
    I've tried a bi-phasic sleep cycle (2 short sleep cycles; 3-4 hours a "day" each time, with a 3-6 hour wake cycle in between) for a few weeks. It worked well enough for me, but with a 10 year old at home, I just couldn't make the timing work out. I'm one that needs at least 8 hours a night; 9 is better.
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Spyro7 15y ago
I wonder how long it takes to recover from the decreased performance. When I was in high school, I could pull an all nighter with ease to take care of an assignment (or to finish a Legend of Zelda game in one straight playing session). Now, in grad school, I needed to pull an all nighter recently and found that I just couldn't do it anymore. I hadn't pulled an all nighter in years and it just seemed to be vastly harder than it used to be. It is too bad the study didn't attempt to see how much sleep was necessary to recover. Would have been nice to know how long the residual effects from decreased sleep lasts. It is now a full week since the end of my semester and I still feel abnormally tired.
credo 15y ago
The report is interesting and it isn't surprising that partial sleep deprivation results in a cognitive deficit. I'd be more interested in understanding the long-term effects of insufficient sleep. Is the cognitive deficit a temporary problem that goes away after a few days (or more of) sufficient sleep OR will sustained lack of sleep (over a long period) result in a long-term problem that persists even after the subject begins to sleep sufficiently.
- ajkessler 15y ago
  Shorter lifespan: http://health.ucsd.edu/news/2002/02_08_Kripke.html http://health.ucsd.edu/news/2002/02_08_Kripke.html Grey hair: http://www.eurekalert.org/pub_releases/2009-02/foas-nla022309.php http://www.eurekalert.org/pub_releases/2009-02/foas-nla02230...
  - mgkimsal 15y ago
    weird. I've had some gray (at least, some I and others could notice) since I was 18 (and quite a lot all these years later). One of my brothers is 15 and has some gray. It's not really saying why the hydrogen peroxide builds up though. :/
- Natsu 15y ago
  In rats, at least, absolutely no sleep over something like a month resulted in death. That scenario was completely unnatural, though. They had to be kept awake with electric shocks or something, so I don't think people are physically capable of going without sleep for that long, unless someone is tormenting them.
- markbao 15y ago
  The problem with this is the search terms are pretty difficult to get right and requires a lot of sifting. Some studies concern themselves with studying "sleep deprivation" as in total sleep deprivation (see the sibling comment in this thread talking about rats). In reality, you (and me) are looking for long-term effects of sleep deprivation, where deprivation = 5-6 hours regularly, 4 or less occasionally. Unfortunately, you can't just Google that. Anyone know of any articles that target this bracket of sleep deprivation (and not something more extreme)?
ajkessler 15y ago
I don't buy the seemingly arbitrary distinction that 8 hours is a good night's sleep. I know people who require 9+ hours per night (ie they appear sleep deprived if they get less than 9 for a few consecutive nights). I know one person who requires about 4 per night (not a forced four where you end up looking 10 years older than you really are after a few years). I do like the idea of testing where your sweet spot is, though. I've never done anything like the PVT, but I've found (through Steve Pavlina's advice) that if you wake up at the same time each day, every day, and simply fall asleep when you're tired at the end of the day, you discover pretty quickly where that sweet spot is. More here: http://www.ajkesslerblog.com/how-to-get-back-9-weeks-of-your-life/ http://www.ajkesslerblog.com/how-to-get-back-9-weeks-of-your...
- bcl 15y ago
  Read the article more closely. Most need 8. There are some who need less, some who need more. The graph might even look like a bell curve ;)
  - kaiwetzel 15y ago
    I was a little disappointed by the article in this regard. While it's mentioned that "There is a small portion of the population — he estimates it at around 5 percent or even less — who, for what researchers think may be genetic reasons, can maintain their performance with five or fewer hours of sleep. (There is also a small percentage who require 9 or 10 hours.)" it would be very interesting to know if there is a larger than 5% group that does just fine with 6 or 7 hours of sleep. Assuming your assumption about the distribution of "needing x hours of sleep to do well" is correct and if we assume that 5% need only 5 hours or less and the mean is at 8 hours (the article is even unclear about what those 8 hours represent so it's a wild guess at best), how large is the percentage of people needing 7.5 hours or less? (Roughly 40% if it's a normal distribution). So what the article says about "most of us" is technically correct the interesting answers for the many of us that presumably need between 5 and 8 hours of sleep is left out. Does it make a difference in what sleep phase people are woken up (after the n hours of sleep their group gets)? I wish more money would be available for this area of research so longer and more detailed studies could be done. And better handouts for journalists.
thebooktocome 15y ago
I've completely stopped going without sleep this since the last semester ended. Of course, we'll see if we last through the next semester... The thing I've noticed is that I have way more free time than I thought I did, because I wasn't explicitly thinking about things in terms of "hmm, I have five hours before bed, I should probably do X". Also, melatonin supplements are my friend. :)
- kunjaan 15y ago
  "I've completely stopped going without sleep this since the last semester ended" That is a lie.
  - killerdark 15y ago
    It's a messy sentence, but not necessarily a lie.
  - jrockway 15y ago
    You are misunderstanding the sentence. He means that he no longer skips sleeping. There is no reason to assume he is lying about this.
- baddox 15y ago
  Another grateful melatonin user here. That stuff got me through college, and I've successfully recommended it to friends (mostly the stereotypical geeks like myself who, left to their own devices, will keep pushing back bedtime a couple of hours every day ad infinitum). Just prepare yourself for some strange dreams for the first couple of months.
  - smokinn 15y ago
    Could you expand on this please? I'm one of those geeks that keeps pushing bedtime back. (Right now I'm waking up around 9pm and going to sleep around 1-2pm. By mid-to-late week I'll probably be back to a regular 8am-midnight.
    - 15y ago
JohnAllen 15y ago
I can tell if I've slept less than 8 hours; I can barely function with anything less than 7; add 30-60 minutes if I've exercised intensely the previous day. The report makes it seem like even if people don't realize it, their performance suffers. I've always been jealous of those that could seemingly sleep for however much time was convenient but not anymore!
deleted 15y ago
[deleted]
killerdark 15y ago
I found a site that lets you do a psychomotor vigilance task (P.V.T) and gives you a report: http://www.wellcomecollection.org/tiredness/index.html http://www.wellcomecollection.org/tiredness/index.html I think I'll use it to test myself, I'll clock my sleeping hours and plot it against the test results. After a few weeks I should be able to see some pattern emerging.
pamelafox 15y ago
I often get told that I don't sleep enough (more like 6 than 8, if that), but for me, my dreams get stranger the longer I sleep, and my day is happier if I can wake up without strange dreams lingering in my head. For example, last night I slept about 8 hours (probably due to wine the night before), and my final dream involved me trying to evade certain death in a circus. I'd prefer to start off my day on cheerier notes. :) I don't use an alarm as I believe in waking up when your body wants you to, after its natural cycles end. Or at least, thats what usually works for me.
- afterburner 15y ago
  Maybe if you used an alarm you'd be forced to wake up during a part of your sleep cycle where you're not dreaming, and so won't remember dreaming.
- astrange 15y ago
  You can get a sleep cycle alarm which will take care of that. Sleep Cycle for iOS works, with the possible problem that you need a power cord long enough to put the device on your bed.
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  - eneveu 15y ago
    I saw a documentary about sleep a few years ago. The main idea was that a sleep cycle lasts approximately 90 minutes, and you feel better rested when you avoid waking up in the middle of a cycle. Since then, I always set my alarm clock to sleep a multiple of 90 minutes: 6h, 7h30min, 9h... (6 hours more often than not, but I might change this, having read this article...) I used to dream all the time. I haven't dreamt since I started doing this. I guess I still have dreams, but I never remember them. I think you only remember dreams when you are woken up in the middle of REM sleep (in the middle of a cycle). A nice benefit of my current sleep pattern, is that I fall asleep very fast, instead of waiting in bed for up to 1 hour like I used to. I hope it's not because I'm sleep deprived, though...
jarin 15y ago
Strangely enough, I've found that since I increased my caffeine intake (to around 900-1200mg/day via energy drinks) I've been sleeping great. I usually go to sleep around 10pm, wake up naturally around 3am, and take a 1 hour nap around 3 pm. I've been drinking a lot of water as well, and I've had no problems focusing on work. I think the nap is the key though.
- Apocryphon 15y ago
  That sounds like segmented sleep. You're channeling your ancestors. http://www.nytimes.com/2006/02/19/opinion/19ekirch.html http://www.nytimes.com/2006/02/19/opinion/19ekirch.html
- anonymoushn 15y ago
  How has 900-1200mg/day worked out for you? I considered it a lot when I was doing 500-600mg/day.
  - jarin 15y ago
    Pretty good, it's basically a max of 4 Engage energy drinks, or 2 of them and a mix of Nos or Monster. I don't feel jittery at all, but I do get a headache if I don't get any caffeine within a few hours of waking up. I used to get a little heart weirdness (a weird beat once in a while), but I've cut down smoking to 1 or 2 cigarettes per day and started drinking more water and the heart weirdness has stopped happening.
    - BlazingFrog 15y ago
      At what point is the physical need for an artificial substance considered an addiction? Not criticizing, just honestly wondering.
      - jarin 15y ago
        Probably when it causes withdrawal symptoms?
pstack 15y ago
I'd settle for even being able to sleep at regular intervals. I have a habit of staying up until I'm tired and waking up when I can't sleep anymore. As a result, I may stay up all day for several days and then stay up all night for several days. Or for several days, I may sleep twice during 24hrs, in completely random periods. I just don't do well with the concept of "well, it's 10pm, so that means it's time to get into bed".
- klochner 15y ago
  get married :)
  - diego 15y ago
    but don't have kids :)
    - deleted 15y ago
      [deleted]
- radu_floricica 15y ago
  Long live melatonin. Gave me a lot more control over my sleep schedule. Plus, the "positive side effects" section on the wikipedia entry is several pages long...
  - Meai 15y ago
    it would be a lot easier to just use eye patches
    - maggit 15y ago
      I don't know what makes you say that, but your statement trivializes the medical disorders of people you know nothing about. Surely eye patches can not replace melatonin for all cases where melatonin is used as a treatment.
  - bennesvig 15y ago
ianl 15y ago
During my first year of university while I was running a start up our of dorm room (modest success) and doing a full course load I was running on four hours of sleep a night and an hour afternoon's nap just before supper. That experience taught me something very important, sleep is crucial. When you are tired you get tunnel vision and all you want to do is complete your task. The long term effects of this on your start up is that you loose the edge to be innovative while trying to solve problems.
- sliverstorm 15y ago
  The worst part is you only want to complete the task, so that you can sleep.
  - FrojoS 15y ago
    No, the worst part is, that you wake up and find you only produced crap.
udoprog 15y ago
Loved this article. I would love to see a simliar test around polyphasic sleep (http://en.wikipedia.org/wiki/Polyphasic_sleep http://en.wikipedia.org/wiki/Polyphasic_sleep). I've actually tried the Uberman sleep schedule for three weeks. This is where you sleep 20 minutes for each 4 hours, totalling in a whopping 2 hours sleep each day. The time gain was insane, and the transition period aswell (between day 3-5 I actually hallucinated due to sleep deprevation). But around 1.5 weeks something strange happened. The 20 minute period that you are allowed to sleep seemed like hours each time, and I would wake up like clockwork on the 20 minute mark. The whole routine is not just a sleep routine, it affects your entire lifestyle. No stimulants, including sugar, high degrees of fat, caffeine. No sedatives, alcohol, drugs (!). And the fact that you are awake during the night when the whole world seems dead is one of the hardest social aspects to handle. What do you do with 6 extra hours each day? Of course there's the aspect of finding somewhere to sleep every 4 hours (was at school at the time), and if you ever missed out, you would have hell to pay. I eventually buckled on a skiing trip with an open bar, had a nice weekend and decided to going back to normal sleeping patterns. Partly because it was not socially acceptable to sleep 2 hours a day (my father threatened to beat some sense into me). But also that there was very little foundation that this kind of sleep pattern was even safe. A couple of million years of evolution had other idea's of when and how long it is necessary to sleep. Other than that, the foundations that I gathered up from this was that when changing your sleeping pattern. The body frantically tries to adapt. By sleeping extremely short periods the body would effectively increase the amount of REM sleep (and yes, I dreamed a lot during these sleeping periods), however, it has not been proven that you don't need the other types of sleep. This is probably a lot of rumours, and a lot of wishful thinking. I personally wish there was some solid backing behind this kind of reasoning (more time awake is awesome!), There are a lot of buzz out there (check google and youtube), but I've been unable to find anything reasonably solid.
- chadp 15y ago
  I thought the article was useless. The only thing that would have been interesting is how (or if) polyphasic naps can replace hours of one's core sleep. Uberman is too extreme to keep up, no one has done it for long periods yet. The Everyman with a core sleep of 3-4.5 hrs a day with 2-3 15 minute naps is much more interesting.
asimjalis 15y ago
I've noticed a difference based on when I wake up. If I wake up early in the morning when it's still dark I find I am quite alert even on a few hours of sleep. If I wake up later I need the eight hours.
sinker 15y ago
Interesting article, but the results don't reflect the performance of those who have adapted to alternative sleep schedules in the long term. The article states that subjects were to maintain their sleep schedule for two weeks. I reckon that any sudden shift in sleep schedules would have a good chance of causing fatigue. A more interesting experiment would be to see how those with alternative sleep schedules that have practiced them in the long term compare to those with 8 a day schedules.
BlazingFrog 15y ago
I envy all of you people who "choose" how many hours of sleep they will have (or not have). After you have kids, especially if their sleep pattern is very inconsistent for no apparent reason, you just take whatever you can get. Unfortunately, you may not be ready to sleep at 10pm that night that your child will decide to wake up at 1am ready to go about her day... Don't pay attention to me. Just another rant from a sleep-deprived parent... ;)
- guygurari 15y ago
  We had a lot of sleep-related problems with our kid. We recently sought professional help and started a program that gives children good sleep habits. We are three weeks in, and the results so far are nothing short of amazing. To put it simply, the kid is sleeping much better, and we got our lives back. One thing we learned the hard way is that following a method from a book is not enough -- you need a professional to guide you through this. There are many pitfalls you don't know about that will lead to failure, and you wont even realize what it is you're doing wrong. Good luck!
  - wizard_2 15y ago
    Can you explain in a bit more depth?
    - edoloughlin 15y ago
      "you need a professional to guide you through this" - I think that's probably enough depth?
      - w1ntermute 15y ago
        No, it's not. He's asking for more detail than that. Otherwise, he wouldn't have responded to a comment saying "you need a professional to guide you through this" with "Can you explain in a bit more depth?".
    - guygurari 15y ago
herf 15y ago
I wonder if f.lux should have a P.V.T. test built in!
patrickk 15y ago
How little sleep one can survive on is something I would like to not to explore. I've struggled with insomnia for over a decade now, and if you are fortunate to consistently get a solid nights sleep and wake up refreshed, then you should appreciate the energy you have. I would much rather sleep well, have less hours in the day to work with and operate at 80-100% mental capacity rather than get less sleep, drink gallons of coffee or other stimulants and struggle with being able to think clearly. Ironically enough, it's exam season now and I may have found a solution - forcing myself to go to bed at midnight, and up at 8-9am (no matter how bad I feel) and taking one caffeine tablet in the morning and one at at lunch, I now have something like regular alertness for the first time consistently in years. It's only a few days into this phase however so who knows how it will pan out. Many a false dawn (pun intended) was had before with solving insomnia!
- TheSOB88 15y ago
  Ever try not exposing yourself to light at night? That's any light - overhead lights, computer screens, lamp poles. Your body produces melatonin based on that kind of input, and anything with significant blue light in it apparently stops you from producing it.
  - patrickk 15y ago
    Believe me I've tried everything over the years. From what I've read about insomnia, it's incredibly subjective; things that work for one person won't help at all for others. Some people can get their "sleep hygiene" (stuff you are supposed to do in order to sleep well) all wrong, and still sleep like a log, e.g. drink plenty coffee late in the evening, noisy environment, lack of exercise, eating heavily close to bedtime etc. If I do any of these things I'm almost guaranteed to have an awful night's sleep. Recently I've bought a Kindle DX (used along with a relatively dim overhead freestanding lamp[1]), and I read that till I feel really sleepy. This satisfies my craving for reading instead of staring at a computer screen. The lack of a backlit screen shining into your retinas really helps! [1] http://p.mdcd.net/product_images/full/2b3c568350aa9759eaa00ae3eead90ad66dba9bd.jpg http://p.mdcd.net/product_images/full/2b3c568350aa9759eaa00a...
knodi 15y ago
I try to sleep little over 8 hour and less then 9 hours, although it doesn't always happen. As the last hour of my sleep I almost always experience lucid dreams and they make my day so much better.
code_duck 15y ago
I wonder when they'll stop forcing active duty military to make do with 4 hours a night.
tmd 15y ago
I have always suspected that I need more sleep than other people. When I tried to live without alarm clock I slept for 9-10 hours every night. It seems to be an enormous waste of time so I usually schedule an alarm after 8 hours. It never occurred to me that one can measure whether the amount of sleep received is right. I just downloaded PEBL (http://pebl.sourceforge.net/ http://pebl.sourceforge.net/), an open source software that includes the P.V.T. test (mentioned in the article) in its battery -- an you can adjust lots of test parameters simply by editing ppbt.pbl. Seems to be working fine (though the test itself is boring and tedious). I'll measure few times a day and try whether 8 vs 10 hours makes a difference in my case.
coreymaass 15y ago
I highly reocmmend Jmes Maas' book Power Sleep. He's a Cornell professor who's studied sleep for decades. This book opened my eyes to just how important enough sleep is. http://www.amazon.com/Power-Sleep-Revolutionary-Prepares-Performance/dp/0060977604 http://www.amazon.com/Power-Sleep-Revolutionary-Prepares-Per...

229 points by robg 15y ago

"P.V.T. is tedious but simple if you’ve been sleeping well. It measures the sustained attention that is vital for pilots, truck drivers, astronauts. Attention is also key for focusing during long meetings; for reading a paragraph just once." I can't say how true that is when you're doing a ton of email all day or research, and its more a function of the sum total of small delays in re-reading that build up over the course of an entire day. Contrasted with a day when your mind is so clear that you require no re-reading, it feels like you are so much more productive. Additional sleep links: 1. Sleep: How to hack your brain (http://www.dustincurtis.com/sleep.html http://www.dustincurtis.com/sleep.html) 2. The 4-Hour Body: Engineering better sleep (http://techcocktail.com/book-preview-the-4-hour-body-engineering-better-sleep-2010-12 http://techcocktail.com/book-preview-the-4-hour-body-enginee...)

scott_s 15y ago
http://news.ycombinator.com/item?id=1464142 http://news.ycombinator.com/item?id=1464142

torstesu 15y ago

It would have been really interesting to see if power naps had any effect on the performance of the subjects that were deprived of sleep. My personal experience is that 15 minutes in the horizontal position improves my awareness and performance. An additional hack is to drink an espresso the moment before you take your power nap - the effect of the caffeine will kick in in about 15 minutes after consumption.

petercooper 15y ago
Or the "siesta" style of sleep generally. That is, the pattern of having a nap in the day and a shorter nighttime sleep.
- michaelcampbell 15y ago
  I've tried a bi-phasic sleep cycle (2 short sleep cycles; 3-4 hours a "day" each time, with a 3-6 hour wake cycle in between) for a few weeks. It worked well enough for me, but with a 10 year old at home, I just couldn't make the timing work out. I'm one that needs at least 8 hours a night; 9 is better.
- deleted 15y ago
  [deleted]

Spyro7 15y ago

I wonder how long it takes to recover from the decreased performance. When I was in high school, I could pull an all nighter with ease to take care of an assignment (or to finish a Legend of Zelda game in one straight playing session). Now, in grad school, I needed to pull an all nighter recently and found that I just couldn't do it anymore. I hadn't pulled an all nighter in years and it just seemed to be vastly harder than it used to be. It is too bad the study didn't attempt to see how much sleep was necessary to recover. Would have been nice to know how long the residual effects from decreased sleep lasts. It is now a full week since the end of my semester and I still feel abnormally tired.

credo 15y ago

The report is interesting and it isn't surprising that partial sleep deprivation results in a cognitive deficit. I'd be more interested in understanding the long-term effects of insufficient sleep. Is the cognitive deficit a temporary problem that goes away after a few days (or more of) sufficient sleep OR will sustained lack of sleep (over a long period) result in a long-term problem that persists even after the subject begins to sleep sufficiently.

ajkessler 15y ago
Shorter lifespan: http://health.ucsd.edu/news/2002/02_08_Kripke.html http://health.ucsd.edu/news/2002/02_08_Kripke.html Grey hair: http://www.eurekalert.org/pub_releases/2009-02/foas-nla022309.php http://www.eurekalert.org/pub_releases/2009-02/foas-nla02230...
- mgkimsal 15y ago
  weird. I've had some gray (at least, some I and others could notice) since I was 18 (and quite a lot all these years later). One of my brothers is 15 and has some gray. It's not really saying why the hydrogen peroxide builds up though. :/
Natsu 15y ago
In rats, at least, absolutely no sleep over something like a month resulted in death. That scenario was completely unnatural, though. They had to be kept awake with electric shocks or something, so I don't think people are physically capable of going without sleep for that long, unless someone is tormenting them.
markbao 15y ago
The problem with this is the search terms are pretty difficult to get right and requires a lot of sifting. Some studies concern themselves with studying "sleep deprivation" as in total sleep deprivation (see the sibling comment in this thread talking about rats). In reality, you (and me) are looking for long-term effects of sleep deprivation, where deprivation = 5-6 hours regularly, 4 or less occasionally. Unfortunately, you can't just Google that. Anyone know of any articles that target this bracket of sleep deprivation (and not something more extreme)?

ajkessler 15y ago

I don't buy the seemingly arbitrary distinction that 8 hours is a good night's sleep. I know people who require 9+ hours per night (ie they appear sleep deprived if they get less than 9 for a few consecutive nights). I know one person who requires about 4 per night (not a forced four where you end up looking 10 years older than you really are after a few years). I do like the idea of testing where your sweet spot is, though. I've never done anything like the PVT, but I've found (through Steve Pavlina's advice) that if you wake up at the same time each day, every day, and simply fall asleep when you're tired at the end of the day, you discover pretty quickly where that sweet spot is. More here: http://www.ajkesslerblog.com/how-to-get-back-9-weeks-of-your-life/ http://www.ajkesslerblog.com/how-to-get-back-9-weeks-of-your...

bcl 15y ago
Read the article more closely. Most need 8. There are some who need less, some who need more. The graph might even look like a bell curve ;)
- kaiwetzel 15y ago
  I was a little disappointed by the article in this regard. While it's mentioned that "There is a small portion of the population — he estimates it at around 5 percent or even less — who, for what researchers think may be genetic reasons, can maintain their performance with five or fewer hours of sleep. (There is also a small percentage who require 9 or 10 hours.)" it would be very interesting to know if there is a larger than 5% group that does just fine with 6 or 7 hours of sleep. Assuming your assumption about the distribution of "needing x hours of sleep to do well" is correct and if we assume that 5% need only 5 hours or less and the mean is at 8 hours (the article is even unclear about what those 8 hours represent so it's a wild guess at best), how large is the percentage of people needing 7.5 hours or less? (Roughly 40% if it's a normal distribution). So what the article says about "most of us" is technically correct the interesting answers for the many of us that presumably need between 5 and 8 hours of sleep is left out. Does it make a difference in what sleep phase people are woken up (after the n hours of sleep their group gets)? I wish more money would be available for this area of research so longer and more detailed studies could be done. And better handouts for journalists.

thebooktocome 15y ago

I've completely stopped going without sleep this since the last semester ended. Of course, we'll see if we last through the next semester... The thing I've noticed is that I have way more free time than I thought I did, because I wasn't explicitly thinking about things in terms of "hmm, I have five hours before bed, I should probably do X". Also, melatonin supplements are my friend. :)

kunjaan 15y ago
"I've completely stopped going without sleep this since the last semester ended" That is a lie.
- killerdark 15y ago
  It's a messy sentence, but not necessarily a lie.
- jrockway 15y ago
  You are misunderstanding the sentence. He means that he no longer skips sleeping. There is no reason to assume he is lying about this.
baddox 15y ago
Another grateful melatonin user here. That stuff got me through college, and I've successfully recommended it to friends (mostly the stereotypical geeks like myself who, left to their own devices, will keep pushing back bedtime a couple of hours every day ad infinitum). Just prepare yourself for some strange dreams for the first couple of months.
- smokinn 15y ago
  Could you expand on this please? I'm one of those geeks that keeps pushing bedtime back. (Right now I'm waking up around 9pm and going to sleep around 1-2pm. By mid-to-late week I'll probably be back to a regular 8am-midnight.
  - 15y ago

JohnAllen 15y ago

I can tell if I've slept less than 8 hours; I can barely function with anything less than 7; add 30-60 minutes if I've exercised intensely the previous day. The report makes it seem like even if people don't realize it, their performance suffers. I've always been jealous of those that could seemingly sleep for however much time was convenient but not anymore!

deleted 15y ago

[deleted]

killerdark 15y ago

I found a site that lets you do a psychomotor vigilance task (P.V.T) and gives you a report: http://www.wellcomecollection.org/tiredness/index.html http://www.wellcomecollection.org/tiredness/index.html I think I'll use it to test myself, I'll clock my sleeping hours and plot it against the test results. After a few weeks I should be able to see some pattern emerging.

pamelafox 15y ago

I often get told that I don't sleep enough (more like 6 than 8, if that), but for me, my dreams get stranger the longer I sleep, and my day is happier if I can wake up without strange dreams lingering in my head. For example, last night I slept about 8 hours (probably due to wine the night before), and my final dream involved me trying to evade certain death in a circus. I'd prefer to start off my day on cheerier notes. :) I don't use an alarm as I believe in waking up when your body wants you to, after its natural cycles end. Or at least, thats what usually works for me.

afterburner 15y ago
Maybe if you used an alarm you'd be forced to wake up during a part of your sleep cycle where you're not dreaming, and so won't remember dreaming.
astrange 15y ago
You can get a sleep cycle alarm which will take care of that. Sleep Cycle for iOS works, with the possible problem that you need a power cord long enough to put the device on your bed.
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- eneveu 15y ago
  I saw a documentary about sleep a few years ago. The main idea was that a sleep cycle lasts approximately 90 minutes, and you feel better rested when you avoid waking up in the middle of a cycle. Since then, I always set my alarm clock to sleep a multiple of 90 minutes: 6h, 7h30min, 9h... (6 hours more often than not, but I might change this, having read this article...) I used to dream all the time. I haven't dreamt since I started doing this. I guess I still have dreams, but I never remember them. I think you only remember dreams when you are woken up in the middle of REM sleep (in the middle of a cycle). A nice benefit of my current sleep pattern, is that I fall asleep very fast, instead of waiting in bed for up to 1 hour like I used to. I hope it's not because I'm sleep deprived, though...

jarin 15y ago

Strangely enough, I've found that since I increased my caffeine intake (to around 900-1200mg/day via energy drinks) I've been sleeping great. I usually go to sleep around 10pm, wake up naturally around 3am, and take a 1 hour nap around 3 pm. I've been drinking a lot of water as well, and I've had no problems focusing on work. I think the nap is the key though.

Apocryphon 15y ago
That sounds like segmented sleep. You're channeling your ancestors. http://www.nytimes.com/2006/02/19/opinion/19ekirch.html http://www.nytimes.com/2006/02/19/opinion/19ekirch.html
anonymoushn 15y ago
How has 900-1200mg/day worked out for you? I considered it a lot when I was doing 500-600mg/day.
- jarin 15y ago
  Pretty good, it's basically a max of 4 Engage energy drinks, or 2 of them and a mix of Nos or Monster. I don't feel jittery at all, but I do get a headache if I don't get any caffeine within a few hours of waking up. I used to get a little heart weirdness (a weird beat once in a while), but I've cut down smoking to 1 or 2 cigarettes per day and started drinking more water and the heart weirdness has stopped happening.
  - BlazingFrog 15y ago
    At what point is the physical need for an artificial substance considered an addiction? Not criticizing, just honestly wondering.
    - jarin 15y ago
      Probably when it causes withdrawal symptoms?

pstack 15y ago

I'd settle for even being able to sleep at regular intervals. I have a habit of staying up until I'm tired and waking up when I can't sleep anymore. As a result, I may stay up all day for several days and then stay up all night for several days. Or for several days, I may sleep twice during 24hrs, in completely random periods. I just don't do well with the concept of "well, it's 10pm, so that means it's time to get into bed".

klochner 15y ago
get married :)
- diego 15y ago
  but don't have kids :)
  - deleted 15y ago
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radu_floricica 15y ago
Long live melatonin. Gave me a lot more control over my sleep schedule. Plus, the "positive side effects" section on the wikipedia entry is several pages long...
- Meai 15y ago
  it would be a lot easier to just use eye patches
  - maggit 15y ago
    I don't know what makes you say that, but your statement trivializes the medical disorders of people you know nothing about. Surely eye patches can not replace melatonin for all cases where melatonin is used as a treatment.
- bennesvig 15y ago

ianl 15y ago

During my first year of university while I was running a start up our of dorm room (modest success) and doing a full course load I was running on four hours of sleep a night and an hour afternoon's nap just before supper. That experience taught me something very important, sleep is crucial. When you are tired you get tunnel vision and all you want to do is complete your task. The long term effects of this on your start up is that you loose the edge to be innovative while trying to solve problems.

sliverstorm 15y ago
The worst part is you only want to complete the task, so that you can sleep.
- FrojoS 15y ago
  No, the worst part is, that you wake up and find you only produced crap.

udoprog 15y ago

Loved this article. I would love to see a simliar test around polyphasic sleep (http://en.wikipedia.org/wiki/Polyphasic_sleep http://en.wikipedia.org/wiki/Polyphasic_sleep). I've actually tried the Uberman sleep schedule for three weeks. This is where you sleep 20 minutes for each 4 hours, totalling in a whopping 2 hours sleep each day. The time gain was insane, and the transition period aswell (between day 3-5 I actually hallucinated due to sleep deprevation). But around 1.5 weeks something strange happened. The 20 minute period that you are allowed to sleep seemed like hours each time, and I would wake up like clockwork on the 20 minute mark. The whole routine is not just a sleep routine, it affects your entire lifestyle. No stimulants, including sugar, high degrees of fat, caffeine. No sedatives, alcohol, drugs (!). And the fact that you are awake during the night when the whole world seems dead is one of the hardest social aspects to handle. What do you do with 6 extra hours each day? Of course there's the aspect of finding somewhere to sleep every 4 hours (was at school at the time), and if you ever missed out, you would have hell to pay. I eventually buckled on a skiing trip with an open bar, had a nice weekend and decided to going back to normal sleeping patterns. Partly because it was not socially acceptable to sleep 2 hours a day (my father threatened to beat some sense into me). But also that there was very little foundation that this kind of sleep pattern was even safe. A couple of million years of evolution had other idea's of when and how long it is necessary to sleep. Other than that, the foundations that I gathered up from this was that when changing your sleeping pattern. The body frantically tries to adapt. By sleeping extremely short periods the body would effectively increase the amount of REM sleep (and yes, I dreamed a lot during these sleeping periods), however, it has not been proven that you don't need the other types of sleep. This is probably a lot of rumours, and a lot of wishful thinking. I personally wish there was some solid backing behind this kind of reasoning (more time awake is awesome!), There are a lot of buzz out there (check google and youtube), but I've been unable to find anything reasonably solid.

chadp 15y ago
I thought the article was useless. The only thing that would have been interesting is how (or if) polyphasic naps can replace hours of one's core sleep. Uberman is too extreme to keep up, no one has done it for long periods yet. The Everyman with a core sleep of 3-4.5 hrs a day with 2-3 15 minute naps is much more interesting.

asimjalis 15y ago

I've noticed a difference based on when I wake up. If I wake up early in the morning when it's still dark I find I am quite alert even on a few hours of sleep. If I wake up later I need the eight hours.

sinker 15y ago

Interesting article, but the results don't reflect the performance of those who have adapted to alternative sleep schedules in the long term. The article states that subjects were to maintain their sleep schedule for two weeks. I reckon that any sudden shift in sleep schedules would have a good chance of causing fatigue. A more interesting experiment would be to see how those with alternative sleep schedules that have practiced them in the long term compare to those with 8 a day schedules.

BlazingFrog 15y ago

I envy all of you people who "choose" how many hours of sleep they will have (or not have). After you have kids, especially if their sleep pattern is very inconsistent for no apparent reason, you just take whatever you can get. Unfortunately, you may not be ready to sleep at 10pm that night that your child will decide to wake up at 1am ready to go about her day... Don't pay attention to me. Just another rant from a sleep-deprived parent... ;)

guygurari 15y ago
We had a lot of sleep-related problems with our kid. We recently sought professional help and started a program that gives children good sleep habits. We are three weeks in, and the results so far are nothing short of amazing. To put it simply, the kid is sleeping much better, and we got our lives back. One thing we learned the hard way is that following a method from a book is not enough -- you need a professional to guide you through this. There are many pitfalls you don't know about that will lead to failure, and you wont even realize what it is you're doing wrong. Good luck!
- wizard_2 15y ago
  Can you explain in a bit more depth?
  - edoloughlin 15y ago
    "you need a professional to guide you through this" - I think that's probably enough depth?
    - w1ntermute 15y ago
      No, it's not. He's asking for more detail than that. Otherwise, he wouldn't have responded to a comment saying "you need a professional to guide you through this" with "Can you explain in a bit more depth?".
  - guygurari 15y ago

herf 15y ago

I wonder if f.lux should have a P.V.T. test built in!

patrickk 15y ago

How little sleep one can survive on is something I would like to not to explore. I've struggled with insomnia for over a decade now, and if you are fortunate to consistently get a solid nights sleep and wake up refreshed, then you should appreciate the energy you have. I would much rather sleep well, have less hours in the day to work with and operate at 80-100% mental capacity rather than get less sleep, drink gallons of coffee or other stimulants and struggle with being able to think clearly. Ironically enough, it's exam season now and I may have found a solution - forcing myself to go to bed at midnight, and up at 8-9am (no matter how bad I feel) and taking one caffeine tablet in the morning and one at at lunch, I now have something like regular alertness for the first time consistently in years. It's only a few days into this phase however so who knows how it will pan out. Many a false dawn (pun intended) was had before with solving insomnia!

TheSOB88 15y ago
Ever try not exposing yourself to light at night? That's any light - overhead lights, computer screens, lamp poles. Your body produces melatonin based on that kind of input, and anything with significant blue light in it apparently stops you from producing it.
- patrickk 15y ago
  Believe me I've tried everything over the years. From what I've read about insomnia, it's incredibly subjective; things that work for one person won't help at all for others. Some people can get their "sleep hygiene" (stuff you are supposed to do in order to sleep well) all wrong, and still sleep like a log, e.g. drink plenty coffee late in the evening, noisy environment, lack of exercise, eating heavily close to bedtime etc. If I do any of these things I'm almost guaranteed to have an awful night's sleep. Recently I've bought a Kindle DX (used along with a relatively dim overhead freestanding lamp[1]), and I read that till I feel really sleepy. This satisfies my craving for reading instead of staring at a computer screen. The lack of a backlit screen shining into your retinas really helps! [1] http://p.mdcd.net/product_images/full/2b3c568350aa9759eaa00ae3eead90ad66dba9bd.jpg http://p.mdcd.net/product_images/full/2b3c568350aa9759eaa00a...

knodi 15y ago

I try to sleep little over 8 hour and less then 9 hours, although it doesn't always happen. As the last hour of my sleep I almost always experience lucid dreams and they make my day so much better.

code_duck 15y ago

I wonder when they'll stop forcing active duty military to make do with 4 hours a night.

tmd 15y ago

I have always suspected that I need more sleep than other people. When I tried to live without alarm clock I slept for 9-10 hours every night. It seems to be an enormous waste of time so I usually schedule an alarm after 8 hours. It never occurred to me that one can measure whether the amount of sleep received is right. I just downloaded PEBL (http://pebl.sourceforge.net/ http://pebl.sourceforge.net/), an open source software that includes the P.V.T. test (mentioned in the article) in its battery -- an you can adjust lots of test parameters simply by editing ppbt.pbl. Seems to be working fine (though the test itself is boring and tedious). I'll measure few times a day and try whether 8 vs 10 hours makes a difference in my case.

coreymaass 15y ago

I highly reocmmend Jmes Maas' book Power Sleep. He's a Cornell professor who's studied sleep for decades. This book opened my eyes to just how important enough sleep is. http://www.amazon.com/Power-Sleep-Revolutionary-Prepares-Performance/dp/0060977604 http://www.amazon.com/Power-Sleep-Revolutionary-Prepares-Per...