
The effects on cognition of sleeping 4 hours per night for 12-14 days - luu
https://guzey.com/science/sleep/14-day-sleep-deprivation-self-experiment/
======
snowwrestler
When I go many days in a row without enough sleep, I find that my cognitive
abilities (i.e. what I am capable of doing) does not seem to significantly
decline--as judged by things I build and people I interact with.

But, my endurance of focus (the amount of time for which I can perform at a
high level) does suffer.

The weird thing is that it doesn't feel like I _can 't_ keep going... it's
just that I sort of somehow don't keep going. I find my mind wandering more
easily, checking in on social media more, and then time passing more quickly
when I do. I'm more likely to look up from Twitter or HN and be surprised at
the time.

In short I don't seem to be any dumber while doing something, but number of
things I get done in a typical time periods declines.

As I have come to understand this impact, it has given me greater empathy for
addicts. My brain doesn't feel like a tired muscle, or like I'm doing anything
wrong in the moment. It's only later, when I look back, that I realize I was
making bad decisions and losing time. It has just reinforced how hard it is to
use decision-making to recover from a situation where the brain has already
been compromised by bad decisions.

~~~
hashmal
> I find that my cognitive abilities (i.e. what I am capable of doing) does
> not seem to significantly decline

It's very common. Studies on sleep deprivation report that subjects do not
feel their cognitive abilities decline. However, measuring cognition using
objective tests does show a significant decrease in these abilities.

~~~
dionidium
See also: "I'm better at pool after 3 beers."

Yeah, no you're not.

~~~
hombre_fatal
A few beers makes you better at anything hindered by anxiety. For many people,
that's playing pool at the bar in front of others. Or speaking a foreign
language. Or holding conversation.

~~~
fiblye
I think a beer can help with anxiety. A few beers just results in
overconfidence.

I will admit it helps with conversation if you don’t normally talk and you’re
around equally drunk people, but a few beers plus a crowd of sober people
doesn’t work as well as most people think it does.

~~~
elbear
I would say it depends on your alcohol tolerance. I get tipsy if I have a
beer. Other friends don't show any signs at 3 beers.

------
spacephysics
Since a few years ago (when I read Why We Sleep [0]) I’ve made it my priority
above all else to allow myself 8 hours of sleep, even if I don’t ‘use’ all of
it. With more sleep, an innumerable amount of things are better (as read in
the book), but subjectively I noticed the following after about a month
straight of good sleep:

* Pain was far more manageable (IBS, MMA injuries)

* Sleep was more restorative when I woke up

* Emotions far more regulated (less irritable)

* Quicker to come up with on the spot jokes, or come up with a refutation to an argument

* Gym performance +30% at least

* Gym recovery faster

* Short and long term memory improvement

* Less health flair ups

* Reduction in brain fog

It’s hard to notice these differences subjectively unless you know what it’s
like when you’re “optimized”

Following a keto (or carnivore with a focus on ketosis) diet leads to a
further boost across the dimensions mentioned above.

I think many people outside of self-optimization don’t realize what they’re
sacrificing when they choose to forego sleep. Even total productivity is
enhanced, despite working less hours due to sleeping.

[0]
[https://en.m.wikipedia.org/wiki/Why_We_Sleep](https://en.m.wikipedia.org/wiki/Why_We_Sleep)

~~~
DominikPeters
The author of the OP is not a fan of Why We Sleep, having found many errors
and misrepresentations [1].

[1] [https://guzey.com/books/why-we-sleep/](https://guzey.com/books/why-we-
sleep/)

~~~
pottertheotter
I had just purchased and starting reading the book when this was first posted
here. I haven't spent much time to look into either side, but I stopped
reading the book because I felt like I may be filling my mind with false
information. And I bought it in the first place thinking an expert was going
to teach the most important things we know so far about sleep. It bums me to
think about this.

~~~
matwood
I can summarize what both the original author, and what the person wrote
criticizing agree on. Yes, sleep is required. Get enough sleep that _you_ feel
rested.

A lot of the critique was around the 8 hours, and the conclusions about what
happens if you get less.

Anecdotally, I never sleep 8+ hours. I also get up without an alarm clock
every single day. I'm not going to stress that I normally sleep ~7 hours and
feel rested when I wake up. I know on the rare occasions if I get less than 6
hours, I'm going to be really tired that night.

~~~
trebidor
One problem with this approach is that if you've always had dysfunctional
sleep, you don't understand what "feeling rested" really means. I had
undiagnosed sleep apnea until my late 20s, and it was insane what a difference
getting a CPAP made. I literally couldn't conceptualize how fatigued I had
been all of my life until I had something to compare it against, and when I
finally started getting restorative sleep my whole life changed.

~~~
haladfire
How did you realize you needed to get a CPAP?

~~~
itake
not OP, but if you have sleep apnea, you typically snore very loudly. You may
not realize you're doing this because you're asleep and alone, but if you
sleep with someone, they will definitely let you know something is wrong and a
dr will tell you to get a CPAP machine.

~~~
PinkMilkshake
It depends on the type. The most common type, Obstructive Sleep Apnea sounds
way worse than loud snoring. If you've ever heard it, it's like the person is
suffocating while they sleep (because they almost are).

------
jkhdigital
> It seems that there’s very high variation in how people respond to sleep
> deprivation.

There you go. It's the tyranny of averages: when variation between humans is
greater than the effect of the intervention.

This reminds me of reading _The How of Happiness_ and learning that happiness
is basically 50% genetics, 10% circumstances and 40% behavior. The author
frames that 40% as a really big number, but I thought about it the other way
around: if you're unlucky enough to be born into the bottom decile of genetic
happiness, then you could _do everything right_ and still be less happy than
someone with really good happiness genes who does everything wrong.

Some people get smashed by any lack of sleep, and some people (most notably
short sleepers) are totally fine with as little as 4 hours a night. There is
no advice that works for both kinds, and formulating advice based on averages
is committing a grave fallacy.

I suppose the world of health research is plagued by this erroneous assumption
that humans are more or less the same. In some ways sure, but in many ways we
are profoundly different.

~~~
Zenbit_UX
I ain't no fancy pants happiness author but I'd posit that happiness is 70%
stupidity and 30% circumstance.

You can be poor and happy or rich and happy, but the smarter you are the less
likely either of those are true. Though being rich certainly helps.

~~~
elbear
Why would it be less likely to be rich and happy the smarter you are?

If you're smarter, it means you can learn more efficiently. If you learn more
efficiently, you get a deeper understanding of the world.

If you understand how something works, you stop having the wrong expectations,
so you're less likely to be unhappy.

~~~
vimslayer
> you stop having the wrong expectations, so you're less likely to be unhappy

This seems like a big leap in logic.

~~~
elbear
Can you point out how?

Here's an exaggerated example: are you upset because you can't fly like a
bird? Probably not, because you know that the world doesn't work that way.

A more subtle example: If you understand why people act the way they act, you
stop being angry when they act in a way that is harmful to others or
themselves. It doesn't mean you just let them do it. You stop them if you can.
But it doesn't make you unhappy. Just like it doesn't make you unhappy if a
wild animal attacks you when go into its cage, for example.

~~~
vimslayer
If my dog or friend or family member would die, I'd be unhappy. Understanding
that death is natural wouldn't do much to that unhappiness. Maybe someday I'd
get over it, or maybe not, but either way, it wouldn't be because I gained
some deeper understanding of life and death.

> it doesn't make you unhappy if a wild animal attacks you when go into its
> cage

Maybe we have different definitions of unhappiness at play here, because being
attacked by an animal would definitely make me unhappy. I mean at the moment
it would mostly make me fear for my life, but afterward when dealing with the
damages I got, I think I would be quite unhappy, and understanding that really
I'm the one to blame wouldn't help. It could make me more unhappy, leaving me
kicking myself for doing something so stupid.

I wouldn't blame the animal if that's what you mean, but that's different from
happiness/unhappiness.

> are you upset because you can't fly like a bird

I think that's more because my hopes and dreams are shaped by the environment
that I've grown up in and, living amongst other humans that can't fly like a
bird, the possibility of doing that has never occurred to me, at least not for
seriously enough to become an issue of happiness.

Had I been a born an elephant with huge ears that all my so-called elephant
friends would torment me for... yeah it would make me pretty unhappy if those
ears wouldn't at least give me the ability to fly.

------
akersten
I've always mused that we could somehow recover some of the "wasted" time of
sleeping. 8 hours every night - a third of a human's lifespan - is just so
much time.

Sadly, I've never found any positive research that there's any way to do it
safely. When I was younger I found schedules like the Uberman[0] and was
amazed by the claim: only 2 hours of sleep a day required, as long as you
stuck to a pretty rigid schedule and were disciplined about napping on time. I
never had the scheduling freedom available to actually give it a go, and
accounts of others trying it seemed to indicate that it was actually pretty
awful to keep up.

This article seems promising, but it's a relatively short experiment. Would be
interesting to see what happened after a year of 4 hour sleep. Based on the
author's description, sounds like their body was trying to force them asleep
at every turn and they had to fight through it. That would be hard to maintain
long-term.

I truly wish one day we can isolate and synthesize whatever magical thing
happens during sleep and recover some useful time. This seems much more
practical than life-expectancy extension to me. As long as, of course,
employers don't take it upon themselves to increase the workday as well. I'd
rather sleep than work.

[0]:
[https://polyphasic.net/schedules/uberman/](https://polyphasic.net/schedules/uberman/)

~~~
elliekelly
Have you tried lucid dreaming? I’ve been a lucid dreamer since I was a kid but
I didn’t know what it was called and I thought that’s how everyone’s dreams
work. Somewhere along the way in law school I started using my dreams to
study. I’d slow-walk through hypothetical fact patterns or anticipate getting
cold-called to recite a case we’d read. It’s been incredibly helpful and once
I realized my classmates had no idea wtf I meant by “I literally study in my
dreams” I found all sorts of groups online who have different techniques you
can try.

I still use lucid dreaming for all sorts of things like practicing for
presentations or running through meetings that I know will be difficult. I’ve
found its most useful (for me at least) when prepping for interactive or
adversarial situations because it forces some part of the brain to “be” both
sides: the question asker and answerer.

~~~
benibela
I have, but I wake up after every lucid dream, so I need to spend more time in
bed to get a full length sleep.

And it only last a few minutes, so there is not enough time to study. Even if
there was, I am always more interesting in flying around.

And most of the time I only reach a half-lucid state. Like tonight I got stuck
in a time loop in a train station. Like I could not leave, because I did not
have the right ticket or travel card. Then on a random train the ticket
inspector wanted to arrest me. I was aware enough to realize that I could
control the environment and could wish the ticket inspector away, but that
just triggered the time loop and put me back in the train station where I
started.

~~~
elliekelly
I actually think the infinite loop, while frustrating, is a good sign! As a
kid I had a recurring dream just about every night (I’m talking _years_ )
about infinite escalators. I’d ride an escalator up and get off only to find
several more to choose from to continue riding up. No matter what escalators I
chose there were always more. No end. No way out. It was pretty stressful for
my elementary school self.

I had a psychologist relative who tried to help me with my “nightmares” by
telling me to just accept the escalator dream instead of being frustrated by
it. Somehow it worked, instead of getting frustrated by the endless escalators
I eventually figured out how to just dutifully ride in peace until I woke up.

Of course that was super boring, but once I stopped frantically searching for
the “right way” to do the escalators I started to figure out all the cool
things I could do to entertain myself on the infinite escalator rides. I still
use an escalator to “start” my lucid dreams if that makes sense. Maybe you’ll
similarly take the train to lucid dreams?

All that is to say that I think the loops are actually the perfect way to
practice if you can manage to abandon the problem-solving urge. Easier said
than done, I know. Best of luck!

------
burlesona
I have come to the (non-scientific) conclusion that this is probably genetic.
I know some people who sleep a lot less than me and seem to be fine with that.
I am not fine with less sleep, but I wish I was because I would love to have
the extra hours each day.

I thought of this for the first time when listening to a Freakonomics podcast
series interviewing major company CEOs. Several of them mentioned schedules
where they average 3-5 hours sleep per night, forever. They all seemed to
think that was fine.

I think I would be severely ill, maybe even literally die, if I averaged 3-5
hours sleep for a duration of many months.

When listening to that series it hit me, maybe this is a genetic thing. In the
same way that you kind of need to be tall to make it into the NBA, maybe you
need the "minimal sleep is okay" gene to make it as a CEO or rocketship
founder. People with those genes get anywhere from 10-20 hours more time per
work week than I do, and that's a big advantage over one week, let alone
compounded over a career.

I don't know what the research says about this, but my lived experience makes
me think it's pretty likely, and unfortunately that also means I may have to
be more realistic about what my body is and is not capable of.

~~~
meddlepal
I think it's more likely some people can just power through lack of sleep.
I've recently started trying to sleep more 6-7+ hours after a decade of doing
the 3-5 hours thing.

I just feel better now with more sleep and while I certainly could perform at
a high level with less sleep I had to exert more energy the longer the day
went on to stay focused.

Genetic? Maybe, or just really good discipline and work ethic?

~~~
oliveshell
Well, yes, but this is a bit of a false dichotomy.

It’s obvious that capacity for discipline and work ethic are not entirely
independent of genetic factors.

~~~
kyuudou
But it's always 30'C and plantains and mangos hang from trees! Why worry!?

------
rkagerer
Was his assessment basically just playing video games? I've noticed that's an
activity I can do proficiently for an extended duration on very little sleep
(along with things like "bulk" coding) but there are others I'm awful at
unless I'm well rested (eg. complex planning, creative efforts like
songwriting) and I've found my communication skills start to become impaired
when I'm really sleep deprived.

I'd be curious to see how he performs on a broader spectrum of cognitive and
even physical assessments.

~~~
T-hawk
What type of video games? That matters a lot to me. I can play a turn-based
game like Civilization completely fine on little sleep (measuring the quality
of play objectively, like by productivity or victory within a certain number
of turns.) Soft real-time games like say a Mario platformer are a little worse
but playable if I'm tired. Hard real-time games with very tight and sensitive
timing like Guitar Hero or high-level Tetris are unplayable at anywhere near
peak form if I'm not fully rested.

~~~
thealfreds
Games requiring long term focus, chess for example, I personally have
difficulty playing when sleep deprived, even though it is turn based. I find I
play at ~200 rating points lower on low sleep.

~~~
adt2bt
Agreed. Many a late sleepless night have I blown 200 points or more on
frustrating blitz games. I would regularly play a game or two during lunch
breaks, climb a good bit, then stay up too late one night and rage throw my
points into the abyss.

------
abtom
> I slept 4 hours a night for 14 days and didn’t find any effects on cognition
> (assessed via Psychomotor Vigilance Task, a custom first-person shooter
> scenario, and SAT).

Remember kids, the only difference between screwing around and science is
writing it down.

~~~
renjimen
So all my late nights playing video games as a teenager could've been
justified had I only phrased it as "doing a PVT for cognitive studies"?!

~~~
loa_in_
You would have to systematically write the circumstances and resulting
observations down

------
toyg
This is one of those posts I wish I could downvote 1000 times. It's the
brogrammer equivalent of fake news: 22-yo kid "makes science" with a sample of
1, some videogames, and a few charts.

You are 22 year old. Your body is at peak condition, built to go out and hunt
for days on little food and little sleep. _Of course_ it will work more or
less fine for a few weeks.

~~~
guzey
I'm the author of this study.

>It's the brogrammer equivalent of fake news: 22-yo kid "makes science" with a
sample of 1, some videogames, and a few charts.

>You are 22 year old. Your body is at peak condition, built to go out and hunt
for days on little food and little sleep. Of course it will work more or less
fine for a few weeks.

I like this comment because its author can't decide whether my study is the
"equivalent of fake news" or whether its results are obviously true.

~~~
toyg
You are clearly unfamiliar with the process of mass-producing fake news. It
typically takes “common sense” and proceeds to mislead it through bad paths.
Which is exactly what you do with this “study”: you over-analyze a situation
that is relatively obvious, with a sample of 1, and _simply by doing so_ you
effectively suggest to generalize its results - which is wrong.

You dropping a caveat mid-page in a single sentence is also the same thing
tabloids do: make a big title about something, then state the opposite
somewhere in the actual small-print article.

~~~
guzey
If I had the opportunity, I would not only downvote you a 1000 times, I would
outright ban you from Hacker News. Your comments are uncharitable, careless,
and abrasive.

>you over-analyze a situation that is relatively obvious, with a sample of 1,
and simply by doing so you effectively suggest to generalize its results -
which is wrong.

>You dropping a caveat mid-page in a single sentence is also the same thing
scummy tabloids do: make a big title about something, then state the opposite
somewhere in the actual small-print article.

The title of my study is:

>The Effects on Cognition of Sleeping 4 Hours per Night for 12-14 Days: a Pre-
Registered Self-Experiment

Which clearly tells the reader that this is a n=1 study. I'm not just dropping
a caveat mid-page. If you somehow missed this, it's your problem, not mine.

------
brewdad
I find it concerning how many people in this thread immediately jump from
believing _Why We Sleep_ is truthful to the book is complete bullshit because
guzey says so. Indeed, some good points are raised by him but at the end of
the day he's just _another fucking guy with a blog_. The entire field deserves
more study but the responses on here feel like Grandma on Facebook passing on
something she read because it feels right.

------
shaftway
I read about the Uberman sleep schedule stuff myself when I was younger and
trying to recover time I "wasted" sleeping. I ended up trying Uberman myself
(15 minute naps, 6x per day).

I did a decent amount of prep work. I talked to my doctor (who basically said
as long as I'm not falling asleep while driving, go for it). I set up ways to
track my cognitive abilities around work (remote software engineer at the
time). I started tracking kill-to-death ratio in favorite first person shooter
(I thought it was a good measure of my innovation, as you can't use the same
tricks for very long against human opponents). I also started tracking my
weight, strength, endurance, and food intake.

It was hard to get into the schedule, and it never really clicked and held.
Eventually I found the schedule to be frustrating and difficult from a social
perspective. So I ended up dropping it a little over a year after I started.

So yeah, a little over a year.

When I analyzed my numbers I didn't see any particular hits in any of the
areas. Work stayed stable (I actually got promoted about 9 months in, so I'm
fairly confident about that). My kill-to-death ratio in the FPS climbed
steadily along a similar trajectory as it had before I started. I found I was
eating more (from ~2300 calories per day to almost 3000 calories to day), but
my weight stayed level. Strength and endurance went up slightly, but that's
probably more because I was checking them regularly versus not doing any
exercise leading up to it.

Would I suggest it to others? No. There were other issues I had with the plan,
more societal. And it was frustrating to not be able to focus on something for
more than 3.5 hours at a time. But it certainly was an interesting time.

~~~
jkhdigital
Was adaptation to Uberman staggeringly difficult? I tried it multiple times,
each time thinking I had come up with the perfect system to push through, and
each time failing. On my final attempt I would go for bike rides to stay awake
and would actually doze off for a few seconds at a time ("microsleeps") even
while riding.

I concluded that physiology determined whether or not something like Uberman
is even possible for a given human being, and I don't have the right
physiology. I have a close friend who tells me that he "doesn't get jet lag"
and seems to have other resistance to circadian disruptions, so I've always
thought that he would be perfect for Uberman but he's not interested so I
can't really test my theory.

~~~
shaftway
> Was adaptation to Uberman staggeringly difficult?

Not sure which adaptation. For dropping into the mechanics of actually
sleeping it was hard, but manageable. I spent a solid 48 hours awake. That
ended at ~9:40 AM and I gave my spouse strict instructions to get me up at
10:00. I fell asleep instantly, and she had trouble getting me up in 20
minutes, but we got there. The second nap I had a couple shots of espresso
right before I went down, and that helped me get back up. The worst part was
that first night. I was sorely tempted. After a weekend I had kind of fallen
in a rut, but it helped to be out and about for a bit, just so that I was
stimulated enough to not feel sleepy. After about two weeks I had fallen into
something that felt normal. Sleeping was kind of a chore then.

Adapting other parts of my life were harder. Close friends knew what was up,
so when we went to a party or something I'd take my naps in a car, or another
room. During the year I'd say I skipped half a dozen naps, and it was always a
battle of willpower to not be completely derailed. I didn't drink, because I
didn't want that to be a reason I skipped a nap.

These were the reasons I ultimately decided to stop, but it was never really a
stable situation. Missing a single nap would throw me off so hard that it was
a battle to go back into it.

------
mattlondon
Having recently had a baby, 4 hours of presumably uninterrupted sleep per
night is an absolutely amazing prospect! Luxury!

What I noticed was it was not so much a lack of sleep, but how the sleep is
interrupted that was the killer. After a few days of barely sleeping longer
than 30 mins at a time I found that memory was hugely impacted, and even
trivial mental arithmetic required concentration. I suspect this is to do with
not being able to get into the appropriate "deep sleep" cycles or something-
something-REM sleep?

If you are up for it, please try the experiment again with 4 hours of sleep
randomly broken up into 10-60 minute chunks (random variability is important -
i.e you go to sleep not knowing how long you've got) distributed throughout
the day, with a minimum of 60 minutes between each chunk. Enjoy :)

~~~
rdgthree
I think this is the interesting question. I'm an extremely deep sleeper and
almost nothing wakes me up while I'm sleeping, but I've found that I naturally
sleep significantly longer if my bedroom has too much light or there's a
significant amount of noise around me while I'm asleep. So despite not
actually waking up consciously, I think I sometimes end up in this partial
wake state where I'm not getting proper REM sleep and as a result, not
actually getting the rest I need.

It wouldn't surprise me if this is often the case for people who feel they
need more sleep. Having proper blackout shades and full silence (via ear plugs
or otherwise) during sleep allows me to sleep a significantly shorter period
of time _as measured by however long I end up staying asleep_. I typically
don't use an alarm, so it's fascinating to be able to notice that natural
difference in how long my body seems to need before booting back up.

Interesting anecdote - the pandemic is what triggered my awareness of this
effect. When I'm at home alone sleeping (typically into the late morning, I'm
a night owl), my dog will sleep with me. When my girlfriend started working
from home from early in the morning, he would wake up with her and bark loudly
at the occasional activity outside. I suddenly couldn't wake up on my normal
schedule, even though I wasn't actually consciously woken up by the barking.
The thought occurred to me that it could still be the barking and something
related to the depth of the sleep, so I tried ear plugs + having my girlfriend
close the bedroom door. Suddenly I was back to sleeping normal hours. Years of
strange sleeping pattern problems were explained in an instant.

------
biophysboy
Guzey had another blog post on Matthew Walker's sleep book posted on HN a
while back. I thought it was a bad faith critique, from my own biophysics
perspective. We had some back and forth, guzey seemed nice & respectful
enough, but I still had my misgivings about the critique. Sleep is very much
an open question.

HN seems to really love maximizing cognition and the overall efficiency of
their life. That said, if you want to try this experiment yourself, know this:
sleep also affects mood, memory, and longevity (e.g. dementia). Chronic sleep
deprivation is not good for you.

~~~
texascloud
It's so strange to see "independent researchers" attempt to poke holes by any
means in an argument meant to protect people from the ill effects of sleep
deprivation, yet provide zero non-anecdotal evidence to support lack of sleep
being beneficial.

Discounting Walker's argument with "he's not thorough" and then providing a
"study" done by one person with no professional research experience appears
fine for HN

~~~
biophysboy
Eh, I understand the motivation though - I think a lot of people on here are
young, driven programmer-types who resent sleep because they see it as
inefficient. I think they're mistaken, but the drive to experiment on yourself
is understandable if you're in that cutthroat world.

------
praptak
"Why We Sleep" by Matthew Walker summarizes quite a lot of research on sleep.
It leaves little doubt - we currently know of no safe way to significantly cut
down sleep.

I haven't seen the research presented in that book being refuted.

~~~
fossuser
I think this book is mostly bullshit - the same author that wrote the linked
HN post dug into that book and there was a ton of manipulative data and just
straight up false claims. [0]

I get a pretty strong pseudoscience vibe from it.

From a previous post:

I got a strong motivated reasoning/bullshit vibe from Walker in this
interview: [https://www.npr.org/2018/07/20/630792401/sleep-scientist-
war...](https://www.npr.org/2018/07/20/630792401/sleep-scientist-warns-
against-walking-through-life-in-an-underslept-state)

Particularly this section:

> “Sleep is not like the bank. So you can't accumulate debt and then try and
> pay it off at a later point in time. And the reason is this - we know that
> if I were to deprive you of sleep for an entire night - take away eight
> hours - and then in the subsequent nights, I give you all of the sleep that
> you want - however much you wish to consume - you never get back all that
> you lost. You will sleep longer, but you will never achieve that full eight-
> hour repayment as it were. So the brain has no capacity to get back that
> lost sleep...”

I don’t think this follows - seems likely to me that sleep is not some linear
time thing and that there’s a standard overhead that doesn’t need to be
repeated to extend and make up the time. This feels like a symptom of not
understanding the mechanism and making a bad assumption.

I also found the “I won’t mention the cognitive failures I can detect”
irritating. If there’s some actual thing to mention, say it - this kind of
thing sets off alarms for me.

It doesn’t surprise me that the rest is similarly bad.

[0]: [https://guzey.com/books/why-we-sleep/](https://guzey.com/books/why-we-
sleep/)

~~~
slm_HN
>I get a pretty strong pseudoscience vibe from it.

I don't quite know how to categorize complaining about pseudoscience based on
a "vibe".

It's not quite irony... maybe it's just humorous. As a member of the post
Alanis Morissette generation I guess I can no longer recognize irony.

~~~
fossuser
By 'vibe' I mean a ton of statements that sound likely to be false or at least
would surprise me if they were true that aren't backed up when you look
closer. The fact that the information is surprising isn't bad itself, but it
spikes curiosity - then when I look deeper there isn't much actually _there_
to support the surprising claims and what is there has a ton of issues.

There's a lot of 'wow, isn't that interesting' talk and deference to authority
on an 'important' issue, but little talk of the actual mechanisms of how
things work, little consideration of obvious counter examples that could be an
explanation (like the one in my comment).

The sense is that the argument is driven by motivated reasoning instead of
trying to understand what's true. Basically starting with a position and
forcing the data to fit your pre-existing position.

It feels like I'm being conned by someone making up bullshit for status or
some other agenda (maybe just sunk costs into an existing theory). Often
bullshit and complex interesting topics can sound similar at first and it's
helpful to have some sense for telling the difference. Otherwise you wander
around impressed by 'energy crystals' and worried about 5g.

~~~
deegles
What agenda could be served by convincing people to get enough sleep?

~~~
Barrin92
I don't know if you can call it an agenda but I think there's something like a
'wellness' or moderation bias in these fields. The idea that you need to
balance out hard work, slow down, and so on.

For example, as it turns out there is little evidence that stretching actually
does anything, yet a lot of experts used to recommend it for decades. Same
with nutrition, 'balanced diets', workouts at low heart rates and so on.

~~~
0xddd
What do you mean that stretching doesn't do anything? Any links to such
evidence? It's a pretty simple experiment to stretch every day for a month and
measure your flexibility gains, so that's quite a bold claim. Do you mean it
has no direct impact on your health?

~~~
Barrin92
>[https://www.theatlantic.com/health/archive/2014/08/stretchin...](https://www.theatlantic.com/health/archive/2014/08/stretching-
before-exercise-is-overrated/376089/)

it actually has negative impact on health and injury in people who do static
stretches in particular is significantly increased. (as is in people with high
levels of flexibility in general)

Nowadays stretches as a warmup are not recommended any more.

------
ping_pong
I discovered that about 1/3 of people can be sleep deprived without any ill
effects, which is the bucket I fall in. Another 1/3 will be disgruntled but
can function at a lower level, but for the last 1/3, it's catastrophic and
can't function at all. That's my wife, and what exemplified this the most was
after having kids. She was almost immediately a wreck but I was able to hold
together with the lack of sleep and spent most of the time being the caregiver
for our kids during the toughest parts of the night.

Previous, I had another incident of sleep where I got 4-5 hours of sleep a day
for about a year, and then it all came crashing down on me eventually.

About 10 years ago, I was doing algorithmic trading globally and would
sometimes watch my trades until 1-2am, and then wake up at 6am to be ready for
US trading. I was doing fine with no problems from lack of sleep, and then one
day after about a year I stopped being able to think clearly. I was having
real trouble thinking or learning new things and had a bad headache. I went to
my doctor and she immediately scheduled an MRI because she thought I might
have a brain tumor. I was scared shitless, but I was able to get the MRI the
next day. After the results came back negative for brain tumor, I thought
maybe it's sleep, so I left work in the middle of the day and fell asleep and
slept for about 16 hours. I realized right there and then I was sleep
deprived, so I stopped trading immediately and focused on trying to sleep
properly.

These days I need close to 7.5 hrs of sleep a day and if I get less, I'll feel
it pretty quickly as opposed to 10 years ago when I felt nothing.

~~~
mattlondon
Almost exactly the same experience here with me Vs my wife with children. She
_needs_ at least one or two significant maps and an early bedtime or she
simply just cannot function, but I seem to be able to handle it a bit better.

I wonder if it is a gender thing, or a coincidence?

~~~
globular-toast
I have read studies that say men benefit more from micro-napping and therefore
can handle shorter nights as long as they can micro-nap. I sleep significantly
shorter nights than my girlfriend. She can sleep for 10-12 hours every night.
I only sleep for 7-8 which means I go to sleep 2-3 hours after her. But I do
micro-nap sometimes. If she naps it's for a long time, usually because of lack
of sleep the night before. She is younger than me, and when I was younger I
used to want to sleep for 10 hours or more, but when I did it messed up my
sleeping pattern (gave me a >24 hour rhythm). So I'm inclined to think she
really does need more sleep at night than me.

------
gregwebs
This study can lead one to conclude that at least some people can function
well for short-term periods of sleep deficit, at least when performing
stimulating activities.

However, we also have studies showing that people are very poor at recognizing
when they are being affected by sleep deficit, so you would need to run this
experiment on yourself first before concluding it applies to you!

------
hpoe
I am fascinated by this, when I was younger I was obsessed with cutting out
sleep, experimenting with polyphasic sleep, energy drinks etc.

I'll add one other anecdote that I don't know what it means, but I had a
project I was working on that was tight deadline, as a result I was only able
to get two hours a sleep a night for about a week. For some reason once I got
past the third day my tiredness and desire to sleep seemed to dip
considerably, and I found that staying awake when engaged in any activity or
discussion was easier. If I was just sitting in a meeting or presentation that
I wasn't very interested in I would doze off, but as long as I was engaged I
felt like I didn't need to sleep at all.

I really wish we knew more about sleep.

~~~
guzey
this is very interesting. Have you tried doing it again?

------
gumby
Back in the 1980s this was expected of MIT undergrads. Took me over a decade
and some difficult effort to extract myself from chronic lack of sleep. I feel
likeI was a lot smarter and more productive when I get 6 hrs minimum. I am a
lot healthier on other metrics as well.

Perhaps this shows that a coupled weeks is OK. Certainly it helped me in my
20s — I could hold down a job and still spend evenings at clubs with my gf and
then wife. So in that way I was a good spouse(!)

A broader study would be interesting too — according to my pediatrician mother
I didn’t sleep much even as a baby / toddler.

------
qu4ku
This may be anecdotal [and sleep deprivation may impact different people
differently] but it has a huge impact on me.

I used to use memrise [flash card style memorisation] to learn new
words/concepts for years [25minutes, the first thing after waking up, every
single day] and I know from experience how sleep, food, hangover, etc. impact
my performance.

Sleep has a gigantic impact on my memory, focus and creativity — I believe it
is responsible for really high variation in IQ points [10 - 20, but that's my
rough guesstimate]. This is a more qualitative assessment but whey I sleep 4
hours it resembles a high level of depression — I lose motivation and all of
my natural curiosity is gone [eg. usually, reading/learning brings me
happiness, but it's all gone when I'm sleep deprived].

That's why I haven't used an alarm clock for years now.

~~~
kyuudou
I have similar results and opinions. I feel that there is some kind of "back-
end processing" that happens during sleep that is crucial for learning. Also,
my sleep tends to be better when I'm doing some kind of workout regularly,
although I need to sleep more. If I'm not working out, I can get by easily
with 6 hours but if I am, absolutely need 8 hrs min. Makes sense to me since a
lot of repair, healing and growth occur while sleeping.

------
jrootabega
> However, for the entire duration of the experiment I had to resist regular
> urges to sleep and on several occasions when I did not want to play video
> games was very close to failing the experiment, having at one point fallen
> asleep in my chair and being awakened a few minutes later by my wife.

I don't really believe this, and I find this interesting and impressive,but
this sounds like a George Costanza scheme after getting caught playing video
games or sleeping too much

~~~
guzey
I'm not sure why you don't really believe this. I didn't really have to
mention this, did I?..

~~~
jrootabega
No I meant I didn't believe it was a scheme

~~~
guzey
Ah.

------
jotm
I definitely couldn't do it. After about a week, my body would just crash/go
to sleep by itself, world be damned.

Same, or rather, worse, when working 12 hours a day for more than ~2 weeks. I
just start thinking "what the fuck am I doing? Why is this worth it?", and if
it's not worth it it would just drive me into a serious depressive mood.

Maybe because I know I could do better than this, that there are other
options. Maybe it's because I made peace with death already. But I think it's
just that I'm physically not made for this kind of overload.

~~~
yovagoyu
Lack of sleep amplifies stress. That's why people argue more frequently and
are more easily agitated when they're sleep deprived.

A lot of the people who say this doesn't affect them seem to be bored video
gamers with no career focus and no stress.

I feel like they'd feel it too if they had to work 12 hours a day and had some
moderate stress.

------
Melting_Harps
> The Effects on Cognition of Sleeping 4 Hours per Night

I lived like this for nearly 5 years. I knew I was taking my health to an
extreme so I did intermittent fasting (but ate one large meal with 7:5:1 fat-
plant/carb-protein ratio and it was all organic) and worked out on a regular
basis before I slept 3-5 times a week. I also had physical labour jobs with
some driving involved on top of typical tech based startup stuff at night
while trying to maintain relationships. It was taxing to say the least.

What I did noticed when I stopped living that way was that it felt like a fog
was lifted and I stopped hearing what had become an omnipresent high pitch
sound like the kind you get when you get hit hard in the head, also before I
could only work optimally for maybe 7 hours max a day so I had to
prioritize/schedule my day accordingly as the rest was a sluggish grind by
comparison. I took cheater naps where I could, but simply put: those were
brutal times.

Also my raw strength got way better, likely because of re-introducing a
recovery period, and my PB and max lifts went up 35% in almost all of my lifts
and exercises. I think I'm at higher than my peak years in early university at
this point on single max lifts.

Personally, I realized my most optimized sleep-work schedule follows a
6-3-6-3-6 routine (6 hours of work, with 3 hours pause to eat/sleep in
between). I've cranked a ton of things that way, its not ideal as it doesn't
allow for much leisure but if I need to get things done and I can afford to
have that schedule I'll do it and get amazing results I can't emulate any
other way.

------
koheripbal
This reminds me of Steve Pavlina who successfully slept 2-3 hrs per day for
5.5 months and reported no ill effects.

source: [https://www.stevepavlina.com/blog/2005/10/polyphasic-
sleep/](https://www.stevepavlina.com/blog/2005/10/polyphasic-sleep/)

We definitely need more people to try variations on this. If you're in
confinement, this is actually a great time to try.

~~~
jotm
I used to really like that guy... But I got a suspicion that sleep experiment
may have been fabricated. There is zero proof beyond the blog posts :/

~~~
koheripbal
Seems lot a lot of effort for seemingly no return at the time.

Without evidence to the contrary, I'm unwilling to doubt him.

~~~
jotm
You're right, there doesn't seem to be much payoff for lying on that
particular topic, especially at that time. Just my suspicion, nothing more.

------
non-entity
I've probably done a month or two of 4 hours a night at least. My sleep is all
over the place. At times, I'll slip into occasional microsleeps at the office
where I basically pass put for a split second
([https://en.m.wikipedia.org/wiki/Microsleep](https://en.m.wikipedia.org/wiki/Microsleep))
Very recently however, I had a two night bout of nearly total sleep
deprivation (I maybe got 3 or 4 hours in a 48 hour period) and it was
absolutely terrible. The second morning it was incredibly difficult to
concentrate and I couldn't keep a coherent thought for a couple hours. However
normally when I'm sleep deprived I can power through the morning hours and be
ok the rest of the day. I did not want another night of that so I grabbed a
variety of otc sleep aids hoping to find one or a combination which would
knock me out. Luckily I was able to knock myself out the next night and ended
that for the time being.

~~~
herman_toothrot
What did you find that helped you get to sleep?

~~~
non-entity
I tried a mix of Unisom (doxylamine) and melatonin that night and I managed to
fall asleep, although it took a good while and didnt think it was gonna happen
at first.

I've had mixed results with melatonin before and DPH based sleep aids
(benadryl, Zquil) tend to make me drowsy as hell for a few hours without
falling asleep If something like that happens again though, I'll probably see
a doctor.

------
mellosouls
An academic study (2007):

[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2656292/](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2656292/)

------
retreatguru
Is it just me, but how can this be taken seriously when the author was trying
to show no result. While I love self experimentation, publishing it as if it’s
valid science is unfortunate.

~~~
guzey
Yes, I believe that you should take this factor into account while reading my
experiment. As I write:

>Lack of effect on cognitive ability is surprising and may reflect true lack
of cognitive impairment, my desire to demonstrate lack of cognitive impairment
due to chronic sleep deprivation and lack of blinding biasing the
measurements, lack of statistical power, and/or other factors.

------
nickbauman
The 12-14 days is crucial here, I think: The US Army tested battle readiness
and effectiveness off and on since WWII and found that you can keep a unit
working well for a couple of weeks with about 4.5 hours a night. After that,
they start to have serious problems. Less than 4.5 hours a night and the
problems start a lot sooner.

~~~
yovagoyu
Do you have a link to this study? Seems like an experiment actually worth
reading about.

~~~
nickbauman
there are literally dozens of them out there

------
icelancer
The guzey_arena_0 test could be biased by his skill level improving over time
by playing it regularly, though if he was an avid FPS gamer prior to the
guzey_arena_0 tests, the asymptotic growth of skill had probably leveled off
in time. I didn't see this addressed in the paper outside of this section:

"I will give myself a sleep opportunity of 8 hours (23:30-07:30). I will
practice the tasks I’m going to use in order to mitigate the most extreme
practice effects during the experiment. I will perform all tasks as follows:

Aimgod guzey_arena_0 at 12:30-12:50, 15:30-15:50, 18:30-18:50 and 21:30-21:50
(I also played about 2 hours of guzey_arena_0 on 2020-03-31 and 2020-04-01
while designing the experiment)"

That might not have been enough to blunt the practice effect.

Still I think it's valid data - might have been better if he played
guzey_arena_0 for a period beforehand on normal sleep until his improvements
leveled off.

~~~
silverdrake11
It looks like he played the game one week before the experiment, during it,
and after three days of recovery and did not find a significant difference

~~~
guzey
Exactly -- practice effects should have been averaged out by this.

------
TinkersW
I'm totally baffled by people claiming to be able to function with less than 8
hours of sleep.

Even 1 night of 6 hours is enough to reduce my mental capabilities immensely.
It is like a fog closes on my mind. Memory suffers particularly, have much
greater difficulty recalling words for things/people(and if the sleep loss is
severe it can become impossible), and any code I write in this state is subpar
when I look at it later. Additionally it often takes me exponentially longer
to write the code when tired..

Also recovery from sleep deprivation requires extra sleep for me. If I follow
up a night of 6 hours with a night of 8 hours, I still feel like I only had 6
hours, requiring me to sleep extra until the 'fog' goes away.

And age has nothing to do with it, had the same problem as teen.

------
karpierz
It seems like the author tested rote activities that were well within their
comfort zone; I'd be curious to see how well they'd perform when trying to
learn something new or work at something that they hadn't practiced before.

~~~
lolc
Given that sleep deprivation is commonly assumed to lead to worsening reaction
times, rote tasks should show an effect. It is interesting they didn't.

Apart from that, I agree that there is more to sleep deprivation than reaction
performance. For example, some of my most creative moments were in highly
sleep-deprived states. But how am I supposed to measure that?

~~~
karpierz
It's interesting, but it doesn't look like the reaction time windows are
particularly tight. 500ms is a generous reaction time. And the FPS scenario
didn't really test snap accuracy or reaction time, the limiting factor on
completion time seems largely dependent on movement.

I think a more interesting metric of reaction time would be using a
competitive FPS or fighting game, that require tight reaction times and
decision making. That way, any change in reaction time will be reflected.

------
rckoepke
I'm amazed by how thoroughly he wrote up the experiment.

~~~
pstuart
yeah, with a sample size of 1 and the subject at a prime point in maturation.

What's the lesson learned from this?

Disclaimer: this experiment would destroy me (but I'm old enough to be the
author's father).

~~~
icelancer
> What's the lesson learned from this?

That sleep is complicated, and that people doing scientific case studies
contributes to the overall corpus of material we have to inspire others.

There need not be a breakthrough everytime you do a case study for science to
be useful and we should stop expecting that.

~~~
pstuart
I understand that sleep is complicated, and also that there's a wide variance
in how people respond to sleep (and lack of same).

I wasn't trying to shit on the OP, just that this made it to the front page of
HN and has no takeaway from it. All I learned is some 22 year old guy was able
to function fine on minimal sleep.

Did I miss something else? I'm genuinely curious because this is actually a
subject of great interest to me.

------
otterpro
If you are doing any sleep-deprivation experiment on self, only thing I ask of
you is to not get behind the wheel and drive. I beg you please not to do any
driving, even if you feel alert and not tired. I had a friend's teen who
blacked out while driving after not sleeping much in 24 hours, causing a minor
accident on the freeway. Falling asleep behind the wheel is most common,
especially around 2-3pm, when the effect of sleep deprivation really starts to
kick in, and brain decides to sleep without a warning.

------
globular-toast
Like many a geek I've "experimented" with my sleeping patterns both
intentionally and unintentionally. I used to drift out of sync with my own
time zone until I was completely nocturnal and would regularly change phase by
staying awake for more than 24 hours. I found this quite hard and while my
cognitive ability might not have suffered, I found that I could think about
nothing but sleep past the 24 hour mark. At the 16-20 hour mark I've done some
of my best ever work.

Going several days with little sleep has always been easier. A single short
night of only 3 hours is almost unnoticed. A second short night becomes
difficult. But I've also noticed my cognitive ability isn't really impacted.
However, my physical performance is degraded heavily. I'm far weaker, clumsier
and my fine motor control is completely shot. I also become really irritable
and just generally not pleasant to be around.

Nowadays I maintain a regular circadian rhythm. I get up at the same time
every day, even on weekends. I try to go to sleep at the right time, but do
sometimes get carried away with something I'm doing. But more importantly, I
try to make sure my sleep _quality_ is high. That means the room at the
correct temperature (as far as I can manage), minimal light and noise
pollution (I moved house specifically for this), and no drugs (it's one reason
I stopped using alcohol). I find that everything is better. I'm stronger, have
better endurance, I'm funnier and more sociable, sex is better, my work is
better. Everything is better.

------
iamleppert
A properly constructed experiment wouldn't alert the subjects sleep is being
measured and instead simply prompt them for how much time they slept in a
questionnaire taken _after_ the tests, or better yet have them wear a tracking
device prior to the study to measure their regular sleep pattern, and only
select subjects for testing that have deviated from their regular sleep
pattern.

My theory is that a sudden change in sleep habits is what causes the cognitive
decline.

------
smeeth
I’m a simple man, I see an N=1 experiment, I ignore it.

------
ChefboyOG
YMMV, but I've found anecdotally, that qualitative aspects of my sleep have an
outsized impact vs. the # of hours, to a point of course.

For instance, in my teens/early twenties, I (like many) was able to sleep
quite a bit less. Lots of late nights traipsing around the internet, lots of
midnight projects.

In my mid-twenties, I suddenly found that I needed much more sleep. If I
didn't get at least 8 hours, I woke up completely drained. Other adults I
spoke to confirmed that this was normal.

Then, I switched apartments and got a new bed. Suddenly, I was waking up much
easier, even with few hours of sleep.

This pattern has repeated a few times throughout my life. I'll notice I'm
waking up more tired than usual, and then something will change—a new room
with more natural light, a better mattress, the loss of something I didn't
realize was stressing me—and I'll suddenly need less sleep.

I'm sure none of this is shocking to anyone, but the key thing for me was that
even when my sleep quality was apparently deteriorated, I didn't notice it. I
still fell asleep easily, I still had dreams, I was still comfortable in my
bed, etc. The sleep cycle, it seems, just wasn't as restorative due to other
factors.

I have a little pet theory that some of the "Super CEOs" we hear about who get
by on 4-5 hours of sleep a night are:

1\. Slightly exaggerating the rigidity of their superhuman schedule (I used to
work in media, and I've worked with an outsized number of people who have
public reputations for this kind of stuff. Anecdotally, I've found that nearly
all exaggerate and sometimes outright lie.)

2\. Adept at compartmentalizing stress and environment, to the extent that
they're able to get quality sleep regardless. This skill would naturally track
other responsibilities in their life as well.

------
29athrowaway
Hours of sleep may not necessarily reflect how well rested a person is.

There are levels of sleep: NREM ("quiet sleep") and REM ("active sleep"). NREM
has 3 stages: 1 (almost awake), 2 (light sleep), 3 (deep sleep).

The deeper your sleep, the most rested you will be. Some people require fewer
hours of sleep because they spend more time in deep sleep.

------
riazrizvi
I find the cognitive tests in the experiment to be insufficient, to make the
argument that _practical_ cognition did not suffer and that the experimenter
was 'productive for 16 hours'. The experiment uses two computer games and a 3
hr test, not much of a comparison to all day non-stop creative software
development. The SAT is one neat little question after another, every
challenge carefully crafted and nicely wrapped. Time to completion is always
relatively easy to calculate.

Creative coding requires a level of alertness that I find is most similar to a
chess game. A working day is around 8 hours. A 3 hour assignment feels like a
half-day.

I wonder how many hours the author could play chess against a good opponent,
on 4 hours of sleep a night? I doubt it approaches '16 productive hours'...

~~~
guzey
I don't know about chess but I coded a lot during the experiment (on day 7 I
spent 11 hours coding, starting with a big block between 8am and 2pm) and felt
great.

~~~
riazrizvi
Hmm, might give it a try then. I was once sleep deprived for about a year in
an old job, and I remember it being so painful I was really turned off to it.
But perhaps it bears a second look. Thanks.

------
swayvil
Speaking of declining cognition, I just spent 4 hours wearing a mask at work.
Wow! I'm woozy, dizzy, muddleheaded and really cranky. Definitely not at my
sharpest. Definitely not in the right frame of mind to be using power-tools.

------
yovagoyu
When I was younger, I somewhat involuntarily got 4 hours of sleep a night for
about 2-3 months.

I remember the first month was fine, but by the second month I'd started to
hallucinate in the day time.

The reason this happened was that I took a night job suddenly (midnight til
8am, but sometimes as late as noon because the overtime was good). I couldn't
get used to the schedule and seem to get more than four hours of sleep during
daylight.

The job was a truck driving job, delivering huge pallets of newspapers out in
time for the paperboys/girls at 5am-7am across a few cities from the printing
press. I remember it was a sweet job, relatively high pay compared to what I'd
had recently and very low stress since the factory was empty, you grab the
clipboard with your route, forklift the pallets onto the truck and listen to
music the rest of the night.

I started to get extremely tired while driving sometime in the second month. I
fought it hard and would stare straight ahead jerking myself awake every
couple of minutes eventually. Not long after that the lines in the road would
insidiously become snakes and I'd be following a river in a half dream sort of
zone.

By the end of the second month I knew I had to quit or I'd end up getting
myself killed on the road, no matter how good the job was. I forced myself to
stay on the extra two weeks because two weeks notice is something my parents
instilled upon me that you always have to do. I kind of agree but feel like I
should have made an exception then.

I was probably 20 at the time.

Some points I'd like to raise: 1\. I don't believe two weeks is long enough to
feel anything. Particularly not if you're young. 2\. Loss of cognition is
really really obvious if you're operating a large metal box that can kill you.
The ability to play video games seems like it could easily fool you into
thinking you're coherent. 3\. Lack of sleep amplifies stress. If you don't
have much stress, it's going to be way easier. Someone falling behind on their
loan payments, working overtime, and taking care of dependents would likely
see a much bigger effect on their life, even with smaller margins of sleep
lost.

------
cco
This should contain a big fat caveat, this appears to be a very young person,
maybe early 20's based on photos? My friend group could pull all nighters and
3-4 am weeknights playing beer pong just fine in college. When we have done so
sparingly in our 30's the next day is completely shot so far as productivity,
we can operate but at greatly diminished capacity.

I'd love to see the author try again in 10 years, I love comparing my current
physical ability, e.g. number of push ups, chin ups etc, to where I was years
ago, its a fun thing to see your body change over time.

~~~
guzey
>This should contain a big fat caveat, this appears to be a very young person,
maybe early 20's based on photos?

The _second_ sentence of the abstract:

>I’m a 22-year-old male and normally I sleep 7-8 hours.

------
PlasticTank
I believe sleep to be one of the most underrated and underutilized health
strategies, I know so many who diet and do all sorts but then are proud of the
fact they only sleep 6 hours a night. Study after study shows how incredibly
deterementail even a slight lack of sleep can be, so much so that I usually
don't believe I've read them correctly to begin with.

I would suggest this book to anyone interested in the topic: Why We Sleep:
Unlocking the Power of Sleep and Dreams – Matthew Walker The author was on Joe
Rogan at some point too but I haven't listened to it.

------
mmmBacon
>> Subjectively, I felt that I gained somewhere between 2 and 3 hours of
productive time every day.

>> I found that I was able to go from “falling asleep” to “fully alert” at all
times by playing video games for 15-20 minutes. I ended up playing video games
for approximately 30-90 minutes a day

Does this mean the actual amount of time gained from this was 2-3 hours or do
we subtract out the amount of time spent playing video games? If we subtract
out the video games there is not much benefit to being sleep deprived,
sometimes only 30 additional productive minutes are gained.

~~~
guzey
Actual amount of time.

------
1bc29b36f623ba8
I sleep for 4-5 hours, get up for about an hour or so, and then try to sleep
another 3-4 hours. Previously, I'd wake up after 4-5 hours and spend 2-3 hours
trying to fall asleep again. An hour of activity during the night seem to be
much more efficient as I get more sleep in total, and obviously feel rested
afterwards.

Occasionally, I've stayed up, and while I've usually felt quite well for
several hours without noticeable decreases in my cognitive abilities, I've
been completely exhausted by lunchtime instead.

Perhaps it is an age thing?

------
bsimpson
I spent one of the hottest summers on record couchsurfing around Europe. The
heat and the casual accommodations both truncated my sleep significantly. I
thought I'd cool off by going mountain biking in the Alps.

I didn't realize how tired I was until I got to the top of the lift. It was
fucking terrifying!

Doing regular vacation stuff like eating and talking to people was totally
fine - I hadn't even noticed I'd accumulated a sleep deficit. But the
attention and the quick reflexes extreme sports require are another matter
entirely.

~~~
Jnr
Don't you think it could have happened because of lack of oxygen in high
altitude?

------
jl2718
My first tour in Afghanistan I started at 3 hours and couldn’t keep that up
after a month or two so I went to four hours for most of the year. It was
crazy but very structured and focused so it worked. I couldn’t do this in the
civilian world; it’s too complicated to deal with relationships and looking
after yourself and big life decisions and existential questions and everything
else. Exhausting. I’ll take 10 if I can get it. I go back to this schedule
when camping and feel great.

------
charles_f
Interesting, I tend to agree about the cognitive capacity, but raters than
focus (as many others here seem to have a problem with under sleep
deprivation), I find that the biggest challenge for me is motivation. Any task
that is inherently rewarding (coding fun stuff, games,...) is no problem.
Anything remotely boring, or just challenging, I just don't find it in me. If
push comes to shove I'll do it, but if I'm allowed to procrastinate I will

------
Kooshaba
You can't fool me, I know this was just an excuse to improve your FPS aim!

Jokes aside, really good read. I had similar goals of cutting out sleep when I
was younger. I'm curious what the authors mood was throughout the experiment.
That's the main thing I've noticed when not getting enough sleep. My output
may be good, I may feel engaged, but every second of the day is torture.

~~~
guzey
Thanks! I didn't notice any effects on mood but I wasn't measuring them
either.

------
chrisco255
Anecdotally, playing a high-intensity video game like an FPS or RTS, wakes me
up and allows me to fend off sleep for a long period of time.

------
peterburkimsher
12-14 days sounds like just enough time to finish taking exams, and my
study/sleep schedule was rather like his during some periods in university.

Sleep deprivation can lead to me being more creative, particularly with
abstract concepts like free will and subatomic physics. I wouldn't want to do
it long-term though.

------
shoulderfake
This completely contradicts my experience with reduced sleep. If I sleep 6 hrs
instead of my usual 8.5 I'm good for nothing that day. I can code for half a
day maybe but thats it. My workouts are also severely affected in terms of max
intensity.

------
saadalem
Tesla sleep by taking 20 mins naps (they said that he sleep just 2/3 hours per
day by taking naps) a la polyphasic way. He is compared to Da Vinci which also
did the same thing, Edison who sleep 4/5 hours ..

Does someone relate to polyphasic sleep ?

~~~
tasty_freeze
About 15 years ago I tried polyphasic sleeping for about two months. I was on
a horrific work crunch and I threw myself into it. I believe my schedule was a
20 minute nap every 3 or 4 hours (I forget now), with one nap being two hours
instead of 20 minutes, a total of about 4 hours a day.

The first week was horrible, but then I got in the groove and I actually
functioned and got work done. I'd often wake up a minute or two before the
alarm went off.

There were a lot of problems. If I ever found myself killing time, eg, waiting
for a test to run, and not actively doing something, I'd want to crash badly.
Sometimes I'd be in the zone working a bug in my code and my "time to take a
nap" alarm would sound and I'd be tempted to keep working. I learned it was
important to stick to the sleep cycle even if I was feeling alert. It was
terrible for family life because if I had to, say, take the kids to the zoo on
Saturday, I'd have to schedule it to fit my sleep pattern, and it wasn't
always possible.

~~~
WildGreenLeave
I don't want to sound racist, but your last sentence is something that struck
me as something oddly european/american. At least in Asia it is just normal to
take a nap somewhere for 30 minutes or so. Just imagine what you could've
achieved if napping wasn't a problem :-)

I'm european but I really like the asian culture where napping is in general
socially acceptable.

------
NewEntryHN
> assessed via Psychomotor Vigilance Task, a custom first-person shooter
> scenario, and SAT

Now try work.

~~~
yovagoyu
Couldn't agree more. Try doing something actually stressful while sleep
deprived.

------
deeblering4
I would approximate working with only 4 hours sleep to working with a post-
hangover fuzzy head.

Sure you could function like that, but doing so regularly isn’t healthy for
you and has a cumulative negative effect on productivity/output.

------
always_left
I normally have always slept for around 4-5 hours a night since I can
remember. Only noticeable health consequence I've noticed is pre-hypertension,
but that could be a mix of anxiety and/or hereditary.

------
meristem
Experiment with n=1: proves subject did not _seem_ impaired during this one
stint when he knew he was being measured, and chose the measures himself, and
had control over the situation and experiment.

------
qwerty456127
What if I also sleep a couple of hours during the day (+4 during the night)?

------
ppezaris
About 20 years ago I slept an average of three hours a night for three years
straight. No ill effects that I could discern. Just another anecdote; not
suggesting that the plural of anecdote is data.

~~~
guzey
Why did you stop?

------
makach
I find the title misleading. The post should add “for me” at the end of the
title, or “for me as a young healthy male”.

This is a personal experience written up as a blog post.

------
bhouston
I find I think different when I don't have enough sleep and I come up with
ideas I normally wouldn't. It is sort of useful actually.

------
diziet
It would be interesting to see resting heart-rate plotted vs this as well --
from my observations lack of sleep tends to impact that a lot.

------
tmaly
I have noticed if I go many days without sleeping, it is easier to make simple
mistakes.

Also, creativity seems to degrade.

------
dhanna
The tasks he's chosen is uninteresting at best.

Did he attempt to learn anything new while sleep-deprived?

~~~
guzey
I spent the majority of my time coding (learning a lot of JS) and learning
biology during the experiment.

------
KboPAacDA3
Submarine crews have been working with these cycles for a century.

------
jbverschoor
Programming does not need too much cognitive ability.

------
hyfgfh
Not a good ideas, just ask the Shadow people

------
cercatrova
Incidentally, I've been sleeping polyphasically for some time now. Of course,
there have been no real studies done on polyphasic sleep and it must be taken
on anecdotal evidence alone. However, I don't feel any ill effects after a
year. My schedule is tamer than others, however; the Everyman 2 consists of a
4.5 hour core sleep and two 20 minute naps [0]. Schedules like Uberman (six 20
minute naps equidistant in time, every 4 hours), Dymaxion, Tesla, and other
nap-only sleeps do not seem to be stable, at least for most people who are not
genetically mutated to sleep less [1].

There are quite some pros as well, such as more time for one; instantly
falling asleep (got rid of my insomnia); removal of substances such as
alcohol, marijuana, and caffeinated drinks like coffee; and lucid dreams with
nearly every sleep. The latter is very useful for me as I can test out ideas
in dreams and see how they could fare, a sort of omnipotent virtual reality.

As I wrote in another comment, the fact that many think polyphasic sleep is
only Uberman or other nap-based schedules with ~2 hour total sleep time is
disappointing to see. There are other schedules on that site that are far
tamer, such as Everyman 1: sleep 6 hours at night, one 20-min nap during the
day, which you could do on a lunch break. There are whole gradations from 9
hours (two 4.5 hour sleeps, not necessarily reduction of total sleep time, but
it gives better sleep for some) to Uberman or Tesla (~2 hour total sleep
time), which by the way is not known to be stable over a longer time period, a
fact that the polyphasic community willingly accepts.

It is particularly disappointing to see because, as another commenter said,
I'd like to see more research on sleep and perhaps synthesizing its effects
into a compound, but if people dismiss these alternate sleep schedules, we may
not fully understand what the brain is doing during sleep, as fewer
researchers are incentivized to study it, thinking it's just BS, which hurts
the field overall.

I do wonder though if the main advantages of polyphasic sleep are that it
enforces a more rigid structure than monophasic sleep; if you miss a nap, or
you oversleep, you're done for. If one could enforce the same level of
scheduling in monophasic sleep, I wonder if they wouldn't have the same
advantage of increased time. It's too easy to make excuses with monophasic
sleep however, saying that you'll just sleep after one more drink / turn of a
game / line of code, so polyphasic sleep acts as an enforcer of such a
schedule, and here is where its true strength lies.

[0]
[https://polyphasic.net/schedules/everyman/](https://polyphasic.net/schedules/everyman/)

[1] [https://www.nih.gov/news-events/nih-research-matters/gene-
id...](https://www.nih.gov/news-events/nih-research-matters/gene-identified-
people-who-need-little-sleep)

