Theses on Sleep

post by guzey · 2022-02-11T12:58:15.300Z · LW · GW · 104 comments

Contents

  Comfortable modern sleep is an unnatural superstimulus. Sleepiness, just like hunger, is normal.
  Depression <-> oversleeping. Mania <-> acute sleep deprivation
  Occasional acute sleep deprivation is good for health and promotes more efficient sleep
  Our priors about sleep research should be weak
  Decreasing sleep by 1-2 hours a night in the long-term has no negative health effects
  Conclusion
  Acknowledgements
  Citation
  Notes
  Common objections
  Appendix: I have no trust in sleep scientists
  Appendix: the idea that sleep’s purpose is metabolite clearance, if not total bs, is massively overhyped
  Appendix: anecdotes about acute sleep deprivation
  Appendix: anecdotes about long-term sleep deprivation
  Appendix: how I wake up after 6 or less hours of sleep
  Appendix: Elon Musk on working 120 hours a week and sleep
  Appendix: Philipp Streicher on homeostasis, its relationship to mania/depression, and on other points I make
  Appendix: Jerome Siegel and Robert Vertes vs the sleep establishment
  Appendix: more papers I found interesting
  References
None
104 comments

Published originally (with all of the footnotes) on my site: https://guzey.com/theses-on-sleep/


Summary: In this essay, I question some of the consensus beliefs about sleep, such as the need for at least 7 hours of sleep for adults, harmfulness of acute sleep deprivation, and harmfulness of long-term sleep deprivation and our inability to adapt to it.

It appears that the evidence for all of these beliefs is much weaker than sleep scientists and public health experts want us to believe. In particular, I conclude that it’s plausible that at least acute sleep deprivation is not only not harmful but beneficial in some contexts and that it’s that we are able to adapt to long-term sleep deprivation.

I also discuss the bidirectional relationship of sleep and mania/depression and the costs of unnecessary sleep, noting that sleeping 1.5 hours per day less results in gaining more than a month of wakefulness per year, every year.


Note: I sleep the normal 7-9 hours if I don’t restrict my sleep. However, stimulants like coffee, modafinil, and adderall seem to have much smaller effect on my cognition than on cognition of most people I know. My brain in general, as you might guess from reading my site, is not very normal. So, be cautious before trying anything with your sleep on the basis of the arguments I lay out below. Specifically do not make any drastic changes to your sleep schedule on the basis of reading this essay and, if you want to experiment with sleep, do it gradually (i.e. varying the average amount of sleep by no more than 30 minutes at a time) and carefully.

Comfortable modern sleep is an unnatural superstimulus. Sleepiness, just like hunger, is normal.

The default argument for sleeping 7-9 hours a night is that this is the amount of sleep most of us get “naturally” when we sleep without using alarms. In this section, I argue against this line of reasoning, using the following analogy:

  1. Experiencing hunger is normal and does not necessarily imply that you are not eating enough. Never being hungry means you are probably eating too much.
  2. Experiencing sleepiness is normal and does not necessarily imply that you are undersleeping. Never being sleepy means you are probably sleeping too much.

Most of us (myself included) eat a lot of junk food and candy if we don’t restrict ourselves. Does this mean that lots of junk food and candy is the “natural” or the “optimal” amount for health?

Obviously, no. Modern junk food and candy are unnatural superstimuli, much tastier and much more abundant than any natural food, so they end up overwhelming our brains with pleasure, especially given that we are bored at work, college, or in high school so much of the day.

What if the only food available to you was junk food and candy?

  1. If you don’t eat any, you starve.
  2. If you eat just enough to be lean, you’ll keep salivating at the sight of pizzas and ice cream and feel distracted and hungry all the time. Importantly, in this situation, the feeling of hunger does not mean that you should eat more – it’s your brain being overpowered by a superstimulus while being bored.
  3. If you eat it as much as you want, you’ll probably eat too much and become fat.
    • And if you eat way too much candy or pizza at once, you’ll be feeling terrible afterwards, however tasty the food was.

Most of us (myself included) sleep 7-9 hours if we don’t have any alarms in the morning and if we get out of bed when we feel like it. Does this mean that 7-9 hours of sleep is the “natural” or the “optimal” amount?

My thesis is: obviously, no. Modern sleep, in its infinite comfort, is an unnatural superstimulus that overwhelms our brains with pleasure and comfort (note: I’m not saying that it’s bad, simply that being in bed today is much more pleasurable than being in “bed” in the past.)

Think about sleep 10,000 years ago. You sleep in a cave, in a hut, or under the sky, with predators and enemy tribes roaming around. You are on a wooden floor, on an animal’s skin, or on the ground. The temperature will probably drop 5-10°C overnight, meaning that if you were comfortable when you were falling asleep, you are going to be freezing when you wake up. Finally, there’s moon shining right at you and all kinds of sounds coming from the forest around you.

In contrast, today: you sleep on your super-comfortable machine-crafted foam of the exact right firmness for you. You are completely safe in your home, protected by thick walls and doors. Your room’s temperature stays roughly constant, ensuring that you stay warm and comfy throughout the night. Finally, you are in a light and sound-insulated environment of your house. And if there’s any kind of disturbance you have eye masks and earplugs.

Does this sound “natural”?

Now, what if the only sleep available to you was modern sleep?

  1. If you don’t sleep at all, you go crazy, because some amount of sleep is necessary.
  2. If you sleep just enough to be awake during the day, you’ll be dreaming of getting a nap at the sight of a bed and will be distracted and sleepy all the time. Importantly, I claim, in this situation, the feeling of sleepiness does not mean that you should sleep more – it’s your brain being overpowered by a superstimulus while being bored.
  3. I claim that if you sleep as much as you want, you’ll probably sleep too much and become more susceptible to depression.
    • And if you sleep way too much at once, you’ll be feeling terrible afterwards, however pleasant the sleep was.

Even if I convinced you about the “sleeping too much” part, you are still probably wondering: but what does depression have to do with anything? Isn’t sleeping a lot good for mental health? Well…

Depression <-> oversleeping. Mania <-> acute sleep deprivation

In this section, I argue that depression triggers/amplifies oversleeping while oversleeping triggers/amplifies depression. Similarly, mania triggers/amplifies acute sleep deprivation while acute sleep deprivation triggers/amplifies mania.


One of the most notable facts about sleep is just how interlinked excessive sleep is with depression and how interlinked sleep deprivation is with mania in bipolar people.

Someone in r/BipolarReddit asked: How many hours do you sleep when stable vs (hypo)manic? Depressed?

Here are all 8 answers that compare hours for manic and depressed states, note the consistency:

Lack of sleep is such a potent trigger for mania that acute sleep deprivation is literally used to treat depression. Aside from ketamine, not sleeping for a night is the only medicine we have to quickly – literally overnight – and reliably (in ~50% of patients) improve mood in depressed patients (until they go to bed, unless you keep advancing their sleep phase ). NOTE: DO NOT TRY THIS IF YOU ARE BIPOLAR, YOU MIGHT GET A MANIC EPISODE.

Figure 1. Copied from Wehr TA. Improvement of depression and triggering of mania by sleep deprivation. JAMA. 1992 Jan 22;267(4):548-51.

Why does the lack of sleep promote manic states while long sleep promotes depression? I don’t know. But here are a couple of pointers to interesting papers relevant to the question: Can non-REM sleep be depressogenic? Brain-derived neurotrophic factor (BDNF) is associated with synapse growth. Sleep deprivation appears to increase BDNF [and therefore neurogenesis?]. Papers that showed up when I googled “sleep deprivation bdnf”: The Brain-Derived Neurotrophic Factor: Missing Link Between Sleep Deprivation, Insomnia, and Depression. The link between sleep, stress and BDNF. BDNF: an indicator of insomnia?. Recovery Sleep Significantly Decreases BDNF In Major Depression Following Therapeutic Sleep Deprivation.

Jeremy Hadfield writes:

My (summarized/simplified) hypothesis based on what I’ve read: depression involves rigid, non-flexible brain states that correspond to rigid depressive world models. Depression also involves a non-updating of models or inability to draw new connections (brain is even literally slightly lighter in depressed patients). Sleep involves revising/simplifying world models based on connections learned during the day, involves pruning unneeded or irrelevant synaptic connections. Thus, excessive sleep + depression = even less world model updating, even more rigid brain, even fewer new connections. Sleep deprivation can resolve this problem at least temporarily by ensuring that you stay awake for longer and keep adding connections, thus compensating for the decreased connection-building caused by depression and “forcing” a brain update (perhaps through neural annealing - see QRI article).

Occasional acute sleep deprivation is good for health and promotes more efficient sleep

In this section, I continue the analogy between eating and sleeping and extend it to exercise. I ask: if fasting and exercising are good, shouldn’t acute sleep deprivation also be good? And I conclude that it is probably good.


Let’s continue our analogy of sleep to eating and add exercise to the mix.

It seems to me that most common arguments against acute sleep deprivation equally “demonstrate” that fasting and exercise are bad.

For example, I ran 7 kilometers 2 days ago and my legs still hurt like hell and I can’t run at all. Does this mean that running is “bad”?

Well, consensus seems to be that dizziness, muscle damage (and thus pain) and decreased physical performance after the run, are not just not bad, but are in fact necessary for the organism to train to run faster or to run longer distances by increasing muscle mass, muscle efficiency, and lung capacity.

What about fasting? When I fast, I am more anxious, I think about food a lot, meaning that focus is more difficult, and I feel cold. And if I decided to fast too much, I would pass out and then die. Does this mean that fasting is “bad”? Well, consensus seems to be that occasional fasting actually activates some “good” kind of stress, promotes healthy autophagy, (obviously) helps to lose weight, etc. and is in fact good.

Now, what happens when I sleep for 2 hours instead of 7 one night? I feel somewhat tingly in my hands, my mood is heightened a little bit, and, if I start watching a movie with my wife at 6pm, I’ll fall asleep. Does this mean that sleeping 2 hours one night is bad for my health?

Obviously no. The only thing we observe is that my organism was subjected to acute stress. However, the reaction to acute stress does not tell us anything about the long-term effects of this kind of stress. As we know, both in running and in fasting, short-term acute stress response results in adaptation and in long-term increase in performance and in benefit to the organism.

I combed through a lot of sleep literature and I haven’t seen a single study that made a parallel to either fasting or exercise and I haven’t seen a single pre-registered RCT that tried to see what happens to someone if you subject them to 1-3 nights per week of acute sleep deprivation and allow to recover the rest of the nights. Do they perform better or worse in the long-term on cognitive tests? Do they have more or less inflammation? Do they need less recovery sleep over time?

I think that the answers are:

  1. Acute sleep deprivation combined with caffeine or some other stimulant that cancels out sleep pressure does not result in decreased cognitive ability at least until 30-40 hours of wakefulness (if this is true, then sleepiness, rather absence of sleep per se is responsible for decreased cognitive performance during acute sleep deprivation).
  2. Occasional acute sleep deprivation has no impact on long-term cognitive ability or health.
  3. Sleep does become more efficient over time and, in complete analogy to exercise, you withstand both acute sleep deprivation better and can function at baseline with a lower amount of sleep in the long-term.

(The only parallel to fasting I’m aware of anyone making is by Nassim Taleb… when he was quote-tweeting me.)


Also see:

Our priors about sleep research should be weak

In this section, I note that most sleep research is extremely unreliable and we shouldn’t conclude much on the basis of it.


Do you believe in power-posing? In ego depletion? In hungry judges and brain training?

If the answer is no, then your priors for our knowledge about sleep should be weak because “sleep science” is mostly just rebranded cognitive psychology, with the vast majority of it being small-n, not pre-registered, p-hacked experiments.

I have been able to find exactly one pre-registered experiment of the impact of prolonged sleep deprivation on cognition. It was published by economists from Harvard and MIT in 2021 and its pre-registered analysis found null or negative effects of sleep on all primary outcomes (note that both the abstract and the main body of this paper report results without the multiple-hypothesis correction, in contradiction to the pre-registration plan of the study. The paper does not mention this change anywhere.).

So why has sleep research not been facing a severe replication crisis, similar to psychology?

First, compared to psychology, where you just have people fill out questionnaires, sleep research is slow, relatively expensive, and requires specialized equipment (e.g. EEG, actigraphs). So skeptical outsiders go for easier targets (like social psychology) while the insiders keep doing the same shoddy experiments because they need to keep their careers going somehow.

Second, imagine if sleep researchers had conclusively shown that sleep is not important for memory, health, etc. – would they get any funding? No. Their jobs are literally predicated on convincing the NIH and other grantmakers that sleep is important. As Patrick McKenzie notes, “If you want a problem solved make it someone’s project. If you want it managed make it someone’s job.”

Figure 2. Relative risk of showing benefit or harm of treatment by year of publication for large NHLBI trials on pharmaceutical and dietary supplement interventions. Copied from Kaplan RM, Irvin VL. Likelihood of null effects of large NHLBI clinical trials has increased over time. PloS one. 2015 Aug 5;10(8):e0132382.

Even in medicine, without pre-registered RCTs truth is extremely difficult to come by, with more than one half of high-impact cancer papers failing to be replicated, and with one half of RCTs without pre-registration of positive outcomes being spun by researchers as providing benefit when there’s none. And this is in medicine, which is infinitely more consequential and rigorous than psychology.


Also see: Appendix: I have no trust in sleep scientists [LW · GW].

Decreasing sleep by 1-2 hours a night in the long-term has no negative health effects

In this section, I outline several lines of evidence that bring me to the conclusion that decreasing sleep by 1-2 hours a night in the long-term has no negative health effects. To summarize:

  1. A sleep researcher who trains sailors to sleep efficiently in order to maximize their race performance believes that 4.5-5.5 hours of sleep is fine.
  2. 70% of 84 hunter-gatherers studied in 2013 slept less than 7 hours per day, with 46% sleeping less than 6 hours.
  3. A single-point mutation can decrease the amount of required sleep by 2 hours, with no negative side-effects.
  4. A brain surgery can decrease the amount of sleep required by 3 hours, with no negative-side effects.
  5. Sleep is not required for memory consolidation.

  1. Claudio Stampi is a Newton, Massachusetts based sleep researcher. But he is not your normal sleep researcher whose career is built on observational studies or p-hacked n=20 experiments that always show “significant” results. He is one of the only sleep researchers with skin in the game: the goal of his research is to maximize performance of sailors by tinkering with their sleep cycles, and he believes that 4.5-5.5 hours of sleep is fine, as long as it’s broken down into core sleep and a series of short (usually 20-minute) naps. Here’s Outside:

“Solo sailing is one of the best models of 24/7 activity, and brains and muscles are required,” Stampi said one day at his home, from which he runs the institute. “If you sleep too much, you don’t win. If you don’t sleep enough, you break.” …

“For those sailors who are seriously competing, Stampi is a necessity,” says Brad Van Liew, a 37-year-old Californian who began working with Stampi in 1998 and went on to become America’s most accomplished solo racer and the winner in his class of the 2002-2003 Around Alone, a 28,000-mile global solo race. “You have to sleep efficiently, or it’s like having a bad set of sails or a boat bottom that isn’t prepared properly.” …

both Golding and MacArthur sleep about the same amount while racing, between 4.5 and 5.5 hours on average in every 24—the minimum amount, Stampi believes, on which humans can get by.

In 2013, scientists tracked the sleep of 84 hunter-gatherers from 3 different tribes (each person’s sleep was measured for about a week but measurements for different groups were taken in different parts of the year). The average amount of sleep among these 84 people was 6.5 hours. Judging by CDC’s “7 hours or more” recommendation, 70% out of these 84 undersleep:

It appears that there is a distinct single-point mutation that allows some people to sleep several hours less than typical on average. A Rare Mutation of β1-Adrenergic Receptor Affects Sleep/Wake Behaviors:

We have identified a mutation in the β1-adrenergic receptor gene in humans who require fewer hours of sleep than most. In vitro, this mutation leads to decreased protein stability and dampened signaling in response to agonist treatment. In vivo, the mice carrying the same mutation demonstrated short sleep behavior. We found that this receptor is highly expressed in the dorsal pons and that these ADRB1+ neurons are active during rapid eye movement (REM) sleep and wakefulness. Activating these neurons can lead to wakefulness, and the activity of these neurons is affected by the mutation. These results highlight the important role of β1-adrenergic receptors in sleep/wake regulation.

The study compares carriers of the mutation in one family to non-carriers in the same family and finds that carriers sleep about 2 hours per day less. Given the complexity of sleep and the multitude of its functions, it seems extremely implausible that just one mutation in the β1-adrenergic receptor gene was able to increase its efficiency by about 25%. It seems that it just made carriers sleep less (due to more stimulation of a group of neurons in the brain responsible for sleep/wakefulness) without anything else obviously changing when compared to non-carriers.

A similar example of a drop in the amount of sleep required without negative side effects and driven by a single factor was described in Development of a Short Sleeper Phenotype after Third Ventriculostomy in a Patient with Ependymal Cysts. To sum up: a 59-year-old patient had chronic hydrocephalus. An endoscopic third ventriculostomy was performed on him. His sleep dropped from 7-8 hours a night to 4-5 hours a night without him becoming sleepy, he stopped being depressed, and his physical or cognitive performance stayed normal, as measured by the doctors.

Sleep is not required for memory consolidation. Jerome Siegel (the author of the hunter-gatherers study mentioned above) writes in Memory Consolidation Is Similar in Waking and Sleep:

Under interference conditions, such as exist during sleep deprivation, subjects, by staying awake, necessarily interacting with the experimenter keeping them awake and experiencing the laboratory environment, will remember more than just the items that are presented. But they may be less able to recall the particular items the experimenter is measuring. This can lead to the mistaken conclusion that sleep is required for memory consolidation [7].

Recent work has, for the first time, dealt with this issue. It was shown that a quiet waking period or a meditative waking state in which the environment is being ignored, produces a gain in recall similar to that seen in sleep, relative to an active waking state or a sleep-deprived state [8–16]. …

REM sleep has been hypothesized to have a key role in memory consolidation [20]. But it has been reported that near total REM sleep deprivation for a period of 14 to 40 days by administration of the monoamine oxidase inhibitor phenelzine has no apparent effect on cognitive function in humans [21]. A systematic study using serotonin or norepinephrine re-uptake inhibitors to suppress REM sleep in humans had no deleterious effects on a variety of learning tasks [22, 23]. Humans rarely survive the damage to the pontine region which when discretely lesioned in animals greatly reduces or eliminates REM sleep [20, 23–25]. However, one such subject with pontine damage that severely reduced REM sleep has been thoroughly studied. The studies show normal or above normal cognitive performance and no deficit in memory formation or recall [26•]. It has been claimed that learning results in greater total amounts of sleep, or greater amounts of REM sleep [27], or greater amounts of sleep spindles, or slow wave activity. However, a systematic test of this hypothesis in 929 human subjects with night-long EEG recording found no such correlation with retention [28•].

The entire Scientific Consensus™ about sleep being essential for memory consolidation appears to be heavily flawed, driven by people like Matthew Walker, and making me lose the last remnants of trust in sleep science that I had.


Also see:

Conclusion

Chadwick worked for several nights straight without sleep on the seminal discovery [of the neutron, for which he was awarded the 1935 Nobel in physics]. When he was done he went to a meeting of the Kapitza Club at Cambridge and gave a talk about it, ending with the words, “Now I wish to be chloroformed and put to sleep”.

Ash Jogalekar

I’m not what they call a “natural short sleeper”. If I don’t restrict my sleep, I often sleep more than 8 hours and I still struggle with getting out of bed. I used to be really scared of not sleeping enough and almost never set the alarm for less than 7.5 hours after going to bed.

My sleep statistics tells me that I slept an average of 5:25 hours over the last 7 days, 5:49 hours over the last 30 days, and 5:57 over the last 180 days hours, meaning that I’m awake for 18 hours per day instead of 16.5 hours. I usually sleep 5.5-6 hours during the night and take a nap a few times a week when sleepy during the day.

This means that I’m gaining 33 days of life every year. 1 more year of life every 11 years. 5 more years of life every 55 years.

Why are people not all over this? Why is everyone in love with charlatans who say that sleeping 5 hours a night will double your risk of cancer, make you pre-diabetic, and cause Alzheimer’s, despite studies showing that people who sleep 5 hours have the same, if not lower, mortality than those who sleep 8 hours? Convincing a million 20-year-olds to sleep an unnecessary hour a day is equivalent, in terms of their hours of wakefulness, to killing 62,500 of them.

I wrote large chunks of this essay having slept less than 1.5 hours over a period of 38 hours. I came up with and developed the biggest arguments of it when I slept an average of 5 hours 39 minutes per day over the preceding 14 days. At this point, I’m pretty sure that the entire “not sleeping ‘enough’ makes you stupid” is a 100% psyop. It makes you somewhat more sleepy, yes. More stupid, no. I literally did an experiment in which I tried to find changes in my cognitive ability after sleeping 4 hours a day for 12-14 days, I couldn’t find any. My friends who I was talking to a lot during the experiment simply didn’t notice anything.

What do I lose due to sleeping 1.5 hours a day less? I’m somewhat more sleepy every day and staying awake during boring calls is even more difficult now. There’s no guarantee that what I’m doing is healthy after all, although, as I explained above, I think that it’s extremely unlikely due to likely adaptation, and likely beneficial effects of sleep deprivation (e.g. increased BDNF, less susceptibility to depression), and since I take a 20-minute nap under my wife’s watch whenever I don’t feel good.


An internationally known expert on acute sleep deprivation Dr. ALIEN SOLDIER (twitter account deleted).

Acknowledgements

I would like to thank (in reverse alphabetic order): Misha Yagudin, Bart Sturm, Ulysse Sabbag, Gavin Leech, Stephen Malina, Anastasia Kuptsova, Jake Koenig, Aleksandr Kotyurgin, Alexander Kim, Basil Halperin, Jeremy Hadfield, Steve Gadd, and Willy Chertman for reading drafts of this essay and for disagreeing with many parts of it vehemently. All errors mine.

Citation

Cite as:

Guzey, Alexey. Theses on Sleep. Guzey.com. 2022 February. Available from https://guzey.com/theses-on-sleep/.

Or download a BibTeX file here.

Notes

Common objections

Objection: “When I’m underslept I notice that I’m less productive.”

Answer: It might be that undersleeping itself causes you to be less productive. However, it might also be the case that there’s an upstream cause that results in both undersleeping and lack of productivity. I think either could be the case depending on the person but understanding what exactly happens is much harder than people typically appreciate when they notice such co-occurrence's.


Figure 5. Causal graph of the "staying up late and feeling demotivated and being unproductive scenario."

Objection: “Driving when you are sleepy is dangerous, therefore you are wrong.”

Answer: Yep, I agree that driving while being sleepy is dangerous and I don’t want anyone to drive, to operate heavy machinery, etc. when they are sleepy. This, however, bears no relationship on any of the arguments I make.

Objection: “The graph that shows more sleep being associated with higher doesn’t tell us anything because sick people tend to sleep more.”

Answer: It is true that some diseases lead to prolonged sleep. However, some diseases also lead to shortened sleep. For example, many stroke patients suffer from insomnia and people with fatal familial insomnia struggle with insomnia. Therefore, if you want to make the argument that the association between longer sleep and higher mortality is not indicative of the effect of sleep, you have to accept that the same is true about shorter sleep and higher mortality.

Appendix: I have no trust in sleep scientists

Why do I bother with all of this theorizing? Why do I think I can discover something about sleep that thousands of them couldn’t discover over many decades?

The reason is that I have approximately 0 trust in the integrity of the field of sleep science.

As you might be aware, 2 years ago I wrote a detailed criticism of the book Why We Sleep written by a Professor of Neuroscience at psychology at UC Berkeley, the world’s leading sleep researcher and the most famous expert on sleep, and the founder and director of the Center for Human Sleep Science at UC Berkeley, Matthew Walker.

Here are just a few of biggest issues (there were many more) with the book.

Walker wrote: “Routinely sleeping less than six or seven hours a night demolishes your immune system, more than doubling your risk of cancer”, despite there being no evidence that cancer in general and sleep are related. There are obviously no RCTs on this, and, in fact, there’s not even a correlation between general cancer risk and sleep duration.

Walker falsified a graph from an academic study in the book.

Walker outright fakes data to support his “sleep epidemic” argument. The data on sleep duration Walker presents on the graph below simply does not exist:


Figure 6. Sleep loss and obesity. Country not specified for sleep data. Copied from Walker M. Why we sleep: Unlocking the power of sleep and dreams. Simon and Schuster; 2017 Oct 3.

Here’s some actual data on sleep duration over time:


Figure 7. Association of year of study with age-adjusted total sleep time (min) for studies in which subjects followed their usual sleep schedule. Copied from Youngstedt SD, Goff EE, Reynolds AM, Kripke DF, Irwin MR, Bootzin RR, Khan N, Jean-Louis G. Has adult sleep duration declined over the last 50+ years?. Sleep medicine reviews. 2016 Aug 1;28:69-85.

By the time my review was published, the book had sold hundreds of thousands if not millions of copies and was praised by the New York Times, The Guardian, and many other highly-respected papers. It was named one of NPR’s favorite books of 2017 while Walker went on a full-blown podcast tour.

Did any sleep scientists voice the concerns they with the book or with Walker? No. They were too busy listening to his keynote at the Cognitive Neuroscience Society 2019 meeting.

Did any sleep scientists voice their concerns after I published my essay detailing its errors and fabrications? No (unless you count people replying to me on Twitter as “voicing a concern”).

Did Walker lose his status in the community, his NIH grants, or any of his appointments? No, no, and no.

I don’t believe that a community of scientists that refuses to police fraud and of which Walker is a foremost representative could be a community of scientists that would produce a trustworthy and dependable body of scientific work.

Appendix: the idea that sleep’s purpose is metabolite clearance, if not total bs, is massively overhyped

Specifically, the original 2013 paper accumulated more than 3,000 (!) citations in less than 10 years and is highly misleading.

The paper is called “Sleep Drives Metabolite Clearance from the Adult Brain”. The abstract says:

The conservation of sleep across all animal species suggests that sleep serves a vital function. We here report that sleep has a critical function in ensuring metabolic homeostasis. Using real-time assessments of tetramethylammonium diffusion and two-photon imaging in live mice, we show that natural sleep or anesthesia are associated with a 60% increase in the interstitial space, resulting in a striking increase in convective exchange of cerebrospinal fluid with interstitial fluid. In turn, convective fluxes of interstitial fluid increased the rate of β-amyloid clearance during sleep. Thus, the restorative function of sleep may be a consequence of the enhanced removal of potentially neurotoxic waste products that accumulate in the awake central nervous system.

At the same time, the paper found that anesthesia without sleep results in the same clearance (paper: “Aβ clearance did not differ between sleeping and anesthetized mice”), meaning that clearance is not caused by sleep per se, but instead only co-occurrs with it. Authors did not mention this in the abstract and mistitled the paper, thus misleading the readers. As far as I can tell, literally nobody pointed this out previously.

And on top of all of this “125I-Aβ1-40 was injected intracortically”, meaning that they did not actually find any brain waste products that would be cleared out. This is an exogenous compound that was injected god knows where disrupting god knows what in the brain.

Appendix: anecdotes about acute sleep deprivation

Max Levchin in Founders at Work:

The product wasn’t really finished, and about a week before the beaming at Buck’s I realized that we weren’t going to be able to do it, because the code wasn’t done. Obviously it was really simple to mock it up—to sort of go, “Beep! Money is received.” But I was so disgusted with the idea. We have this security company; how could I possibly use a mock-up for something worth $4.5 million? What if it crashes? What if it shows something? I’ll have to go and commit ritual suicide to avoid any sort of embarrassment. So instead of just getting the mock-up done and getting reasonable rest, my two coders and I coded nonstop for 5 days. I think some people slept; I know I didn’t sleep at all. It was just this insane marathon where we were like, “We have to get this thing working.” It actually wound up working perfectly. The beaming was at 10:00 a.m.; we were done at 9:00 a.m.

/u/CPlusPlusDeveloper on Gwern’s Writing in the Morning:

We know that acute sleep deprivation seems to have a manic and euphoric effect on at least some percent of the population some percent of the time. For example staying up all night is one of the most effective ways to temporarily aleve depression. Of course the problem is that chronic sleep deprivation has the opposite effect, and the temporary mania and euphoria is not sustainable.

My speculative take is that whatever this mechanism, it was the main reason you experienced a productivity boost. By waking up early you intentionally were fighting against your chronobiology, hence adding an element of acute sleep deprivation regardless of how many hours you got the night before. That mania fuels an amphetamine like focus.

The upshot, if my hypothesis is true, is that waking up early would not produce similar gains if you did it everyday. Like the depressive who stays up all night, it may feels like you’ve discovered an intervention that will pay lasting gains. But if you were to actually make it part of your recurring lifestyle, the benefits would stop, and eventually the impact would work in reverse.

Along those lines that’s probably why you naturally tend to stop conforming to that pattern after a few days. As acute sleep deprivation becomes chronic, you’re most likely intuitively recognizing that the pattern has crossed over to the point of being counter-productive.

Lots of writers and software engineers note that their creative juices start flowing by evening extending late into the night - I think this phenomenon is closely related to the one described in the comment above.

Brian Timar:

sleep anecdote- In undergrad I had zero sleep before several major tests; also before quals in grad school. Basically wouldn’t sleep before things I really considered important (this included morning meetings I didn’t want to miss!). On such occasions I would feel:

  • miserable, then
  • absurd and in a good humor, weirdly elated, then
  • Super PumpedTM, and

really sharp when the test (or whatever) actually started.

Appendix: anecdotes about long-term sleep deprivation

I once tried to cheat sleep, and for a year I succeeded (strong peak-performance-sailing vibes):

In the summer of 2009, I was finishing the first—and toughest—year of my doctorate. …

To keep up this crazy sleep schedule, I always needed a good reason to wake up the next morning after my 3.5-hour nighttime sleep. So before I went to bed, I reviewed the day gone past and planned what I would do the next day. I’ve carried on with this habit, and it serves me well even today.

But the Everyman schedule was reasonably flexible. Some days when I missed a nap, I simply slept a little more at night. There were also days when I couldn’t manage a single nap, but it didn’t seem to affect me very much the next day.

To the surprise of many, and even myself, I had managed to be on the polyphasic schedule for more than a year. But then came a conference where for a week I could not get a single nap. It was unsettling but I was sure I would be able to get back to sleeping polyphasic without too much trouble.

I was wrong. When I tried to get back into the schedule, I couldn’t find the motivation to do it; I didn’t have the same urgent goals that I had had a year ago. So I returned to sleeping like an average human.

James Gleck in Chaos on Mitch Feigenbaum:

In the spring of 1976 he entered a mode of existence more intense than any he had lived through. He would concentrate as if in a trance, programming furiously, scribbling with his pencil, programming again. He could not call C division for help, because that would mean signing off the computer to use the telephone, and reconnection was chancy. He could not stop for more than five minutes’ thought, because the computer would automatically disconnect his line. Every so often the computer would go down anyway, leaving him shaking with adrenaline. He worked for two months without pause. His functional day was twenty-two hours. He would try to go to sleep in a kind of buzz, and awaken two hours later with his thoughts exactly where he had left them. His diet was strictly coffee. (Even when healthy and at peace, Feigenbaum subsisted exclusively on the reddest possible meat, coffee, and red wine. His friends speculated that he must be getting his vitamins from cigarettes.)

In the end, a doctor called it off. He prescribed a modest regimen of Valium and an enforced vacation. But by then Feigenbaum had created a universal theory.

Ryan Kulp’s experience with decreasing the amount of sleep by several hours:

i began learning to code in 2015. since i was working full-time i needed to maximize after-hours to learn quickly. i experimented for 10 days straight… go to sleep at 4am, wake up at 8am for work. felt fine.

actually, the first 5-10 minutes of “getting up” after 3-4 hours of sleep sucks more than if i sleep ~8 hours. but after 15 mins of moving around, a shower, etc, i feel as if i slept 8 hours.

since then i’ve routinely slept 4-6 hours /day and definitely been more productive. i think if more people experimented for themselves and had the same “aha” moment i did (that you feel fine after the initial gut-wrenching “i slept too little” reaction), they’d get more done too.

This is a very good point that shows that: there’s (1) how sleepy we feel when waking up and (2) how sleepy we feel during the day. (2) is probably more important but most people are focused on (1) and the implicit assumption is that poor (1) leads to (2) – which is unwarranted.

Appendix: how I wake up after 6 or less hours of sleep

Nabeel Qureshi writes:

you’re combining two things here: (1) your brain is overpowered by the comfy soft temp-controlled bed (2) you’re bored. they might both be right but i think you conflate them, and they’re separate arguments. this is important bc i think the strongest counterargument to what you’re saying is the classic experience of: you force yourself to wake up early (say 6), you have a project you’re genuinely excited about (hence #2 is false), but when you sit down to work, you’re tired and can’t quite focus. in this scenario, i think your theory would say that i’m not really that excited about what i’m doing, because if i were (see video game argument) then i’d be awake. i’d disagree and say that the researcher should just go take a nap, and they’ll probably be able to make more progress per hour than the extra hours they gain… trying to force yourself to do something while underslept, subjectively, feels hellish. i’m sure you’ve had this experience - did you figure out a workaround?

It is completely true that if you are excited by a project but it’s not super stimulating, it’s still very easy to wake up after less than usual number of hours of sleep and feel sleepy and terrible. This is true for me as well. I found a solution to this: instead of heading straight to the computer, I first unload the clean plates from the dishwasher and load it with dirty plates. This activity is quite special in that it is:

  1. Physical (includes lots of moving around physical objects to/from around the kitchen).
    • Why this matters: moving around wakes up the body much better than just sitting.
  2. Mental (the objects are always in different places, the arrangement of them within the dishwasher is always somewhat different and you need to effectively solve a new spatial organization problem every day to load everything efficiently.
    • Why this matters: moving around in automatic pre-defined movements eventually results in the brain just performing these movements on autopilot without waking up.
  3. Very moderate in effort (no lifting of heavy things, nothing that requires complex concentration).
    • why this matters: I and people I know tend to find intense physical activities right after waking up really unpleasant and somewhat nauseating.

In about 90% of the cases, 10 minutes later when I’m done with the dishwasher, I find that I’m fully awake and don’t actually want to sleep anymore. In the remaining 10% of the cases, I stay awake and work until my wife wakes up and then go take a 20-minute nap under her watch (and take as many 20-minute naps as I need during the day, although I only end up taking a few naps a week and rarely more than one per day, unless I’m sick).

Appendix: Elon Musk on working 120 hours a week and sleep

CNBC:

On Tesla’s first-quarter earnings conference call in May, Musk referred to inquiries from Wall Street analysts as “boring, bonehead questions” and as “so dry. They’re killing me.” On the next earnings conference call in August, Musk said he was sorry for “being impolite” on the previous call.

“Obviously I think there’s really no excuse for bad manners and I was violating my own rule in that regard. There are reasons for it, I got no sleep, 120 hour weeks, but nonetheless, there is still no excuse, so my apologies for not being polite on the prior call,” Musk said.

Later in August, in conversation with the New York Times, Musk reported using prescription sleep medication Ambien to sleep.

“Yeah. It’s not like for fun or something,” Musk told Swisher Wednesday. “If you’re super stressed, you can’t go to sleep. You either have a choice of, like, okay, I’ll have zero sleep and then my brain won’t work tomorrow, or you’re gonna take some kind of sleep medication to fall asleep.”

Musk said he was working such insane hours to get Tesla through the ramp up in production for its Model 3 vehicle. ”[A]s a startup, a car company, it is far more difficult to be successful than if you’re an established, entrenched brand. It is absurd that Tesla is alive. Absurd! Absurd.”

Appendix: Philipp Streicher on homeostasis, its relationship to mania/depression, and on other points I make

Philipp (@Cautes):

First, I wanted to share a way of thinking about some of your findings that builds on the idea of a homeostatic control system (brought to you from engineering via cybernetics). The classic example is a thermostat, which keeps temperature of a room close to a set point. Biology is quite a bit more messy than this, of course, but the body makes use of a plenty of feedback mechanisms to stay close to set points as well. You’re right in pointing out that these set points don’t need to be healthy though. For example, measured via EEG, PTSD patients have alpha power (which primarily modulates neural inhibition in frontal, parietal and occipital areas of the brain) set points far below that of healthy control groups. One way to deal with these suboptimal set points is to simply disrupt the system. Here’s a model that makes this point nicely: imagine all possible brain state dynamics as a two-dimensional plane and place a ball on it which represents the current brain state space. As the ball moves, the brain dynamics change as well (in frequency, phase, amplitude - you name it). On the plane, you have basins that give stability to the brain state, and repellers in the form of hills, as well as random noise and outside interference which drives the ball into various directions. Sometimes the ball will get stuck in basins which are highly suboptimal, but they are deep enough that exploration of other set points is not possible. If the system is disrupted, the ball might get jolted out of its basin though, and be again able to fall into a more optimal position.

With that said, there’s plenty of evidence that stability in itself (even within better basins) is suboptimal for perfect health, because contexts change. For example, people who are very physically healthy (athletes, for example), tend to have far greater variance in the time interval between individual heart beats (heart rate variability) than even the average person, and as the average person gets healthier, their heart rate variability increases as well. Basically, the body becomes more resilient by introducing a noise signal that produces chaotic fluctuations to homeostatic control mechanisms (controlled allostasis) and there are good reasons to think that this is true of psychological health as well.

Because of this, I think that you’re right in suggesting that varying the amount of time you sleep is a good thing - especially if you’re currently struggling with depression or mania. Not even necessarily because sleep per se is the culprit, but because it might dislodge a ball stuck in a suboptimal basin, so to speak. Depressed people tend to oversleep, people with mania tend to sleep too little, so steering in the opposite direction is only logical. For perfectly healthy people, sleep cycling is probably the best way to go - kind of a mirroring the logic of heart rate variability: introduce some noise to keep your body on your toes. It’s just like fasting, working out, cold exposure, saunas, etc. - it’s al about producing stressors on the body which stir up repair processes which keep you healthy (and biologically younger). I have done plenty of self-experiments with polyphasic 5-6 hour sleeping (similar to the the approach studied by Stampi, who you mentioned), with no negative consequences. The main thing that makes it impractical is that intermittent napping is sometimes hard to combine with professional responsibilities and a social life.

As a side note, because you ask the question about why depressed people sleep longer, and people with mania sleep less, the answer to this is very likely highly multi-causal. With that said, I wanted to point out that depressed people generally exhibit excessive alpha activity in eyes-open waking states, which normally becomes more pronounced in people as they drift off to sleep (because of the neural inhibition function). We also have reason to believe that it mediates between BDNF and subclinical depressed mood, so that’s a link to something else you talk about in your article. As for mania, I haven’t looked at this myself, but I remember hearing that it’s almost a mirror image, with generally decreased synchronisation of slower oscillations and heightened faster rhythms, generally associated with greater arousal and wakefulness.

One last thing: as you point out, sleep is likely not required for memory retention. Any claim that sleep is about any specific cognitive function should be suspect on the principle that the phenomenon of sleep predates the development of organisms with brains - it can’t have evolved specifically for something as high-level as memory retention. It’s more likely about something more basic like general metabolic health.

Appendix: Jerome Siegel and Robert Vertes vs the sleep establishment

Time for the Sleep Community to Take a Critical Look at the Purported Role of Sleep in Memory Processing by Robert Vertes and Jerome Siegel (a reply to Walker claiming that the debate on memory processing in sleep is essentially settled):

The present ‘debate’ was sparked by an editorial by Robert Stickgold in SLEEP on an article in that issue by Schabus et a on paired associate learning and sleep spindles in humans

Regarding Stickgold’s editorial, I was particularly troubled by his opening statement, as follows: “The study of sleep-dependent memory consolidation has moved beyond the question of whether it exists to questions of its extent and of the mechanisms supporting it”. He then proceeded to cite evidence justifying this statement. Surprisingly, there was no mention of opposing views or a discussion of data inconsistent with the sleep-memory consolidation (S-MC) hypothesis. It seemed that the controversial nature of this issue should have at least been acknowledged, but apparently to do so would have undermined Stickgold’s position that the door is closed on this debate and only the fine points need be resolved. …

  1. By all accounts, sleep does not serve a role in declarative memory. As reviewed by Smith, with few exceptions, reports have shown that depriving subjects of REM sleep does not disrupt learning/memory, or exposure to intense learning situations does not produce subsequent increases in REM sleep. Smith concluded: “REM sleep is not involved with consolidation of declarative material.” The study by Schabus et al (see above) is another example that the learning of declarative material is unaffected by sleep. They reported that subjects showed no significant difference in the percentage of word-pairs correctly recalled before and after 8 hours of sleep. Or as Stickgold stated in his editorial [the editorial Vertes and Siegel are replying to], “Performance in the morning was essentially unchanged from the night before”. It would seem important for Stickgold/Walker to acknowledge that the debate on sleep and memory has been reduced to a consideration of procedural memory – to the exclusion of declarative memory. If there are exceptions, they should note.
  2. Several lines of evidence indicate that REM sleep is not involved in memory processing/consolidation – or at least not in humans. Perhaps the strongest argument for this is the demonstration that the marked suppression or elimination of REM sleep in individuals with brainstem lesions or on antidepressant drugs has no detrimental effect on cognition. A classic case is that of an Israeli man who at the age of 19 suffered damage to the brainstem from shrapnel from a gunshot wound, and when examined at the age of 33 he showed no REM sleep. The man, now 55, is a lawyer, a painter and interestingly the editor of a puzzle column for an Israeli magazine. Recently commenting on his ‘famous’ patient, Peretz Lavie stated that “he is probably the most normal person I know and one of the most successful ones”. There are several other well documented cases of individuals with greatly reduced or absent REM sleep that exhibit no apparent cognitive deficits. It would seem that these individuals would be a valuable resource for examining the role of sleep in memory. …

In Memory Consolidation Is Similar in Waking and Sleep cited above, Siegel notes:

To critically evaluate this hypothesis [that sleep has a critical role in memory consolidation], we must take “interference” effects into account. If you learn something before or after the experimenter induced learning that is being measured in the typical sleep-memory study, it degrades recall of the tested information. For example if you tell a subject that the capital of Australia is Canberra and then allow the subject to have a normal night’s sleep, there is a high probability that the subject will remember this upon awakening. If on the other hand you tell the subject that the capital of Australia is Canberra, the capital of Brazil is Brasilia, the capital of Canada is Ottawa, the capital of Iceland is Reykjavik, the capital of Libya is Tripoli, the capital of Pakistan is Islamabad, etc., it is much less likely the subject will remember the capital of Australia. The effect of proactive and retroactive interference is dependent on the temporal juxtaposition, complexity, and similarity of the encountered material to the associations being tested. Interference is a well-established concept in the learning literature [1–6]. Under interference conditions, such as exist during sleep deprivation, subjects, by staying awake, necessarily interacting with the experimenter keeping them awake and experiencing the laboratory environment, will remember more than just the items that are presented. But they may be less able to recall the particular items the experimenter is measuring. This can lead to the mistaken conclusion that sleep is required for memory consolidation [7].

Fur Seals Suppress REM Sleep for Very Long Periods without Subsequent Rebound:

Virtually all land mammals and birds have two sleep states: slow-wave sleep (SWS) and rapid eye movement (REM) sleep [1, 2]. After deprivation of REM sleep by repeated awakenings, mammals increase REM sleep time [3], supporting the idea that REM sleep is homeostatically regulated. *Some evidence suggests that periods of REM sleep deprivation for a week or more cause physiological dysfunction and eventual death [4, 5]. However, separating the effects of REM sleep loss from the stress of repeated awakening is difficult [2, 6]. The northern fur seal (Callorhinus ursinus) is a semiaquatic mammal [7]. It can sleep on land and in seawater. The fur seal is unique in showing both the bilateral SWS seen in most mammals and the asymmetric sleep previously reported in cetaceans [8]. Here we show that when the fur seal stays in seawater, where it spends most of its life [7], it goes without or greatly reduces REM sleep for days or weeks. After this nearly complete elimination of REM, it displays minimal or no REM rebound upon returning to baseline conditions. Our data are consistent with the hypothesis that REM sleep may serve to reverse the reduced brain temperature and metabolism effects of bilateral nonREM sleep, a state that is greatly reduced when the fur seal is in the seawater, rather than REM sleep being directly homeostatically regulated. This can explain the absence of REM sleep in the dolphin and other cetaceans and its increasing proportion as the end of the sleep period approaches in humans and other mammals.

Appendix: more papers I found interesting

Long-term moderate elevation of corticosterone facilitates avian food-caching behaviour and enhances spatial memory

It is widely assumed that chronic stress and corresponding chronic elevations of glucocorticoid levels have deleterious effects on animals' brain functions such as learning and memory. Some animals, however, appear to maintain moderately elevated levels of glucocorticoids over long periods of time under natural energetically demanding conditions, and it is not clear whether such chronic but moderate elevations may be adaptive. I implanted wild–caught food–caching mountain chickadees (Poecile gambeli), which rely at least in part on spatial memory to find their caches, with 90–day continuous time–release corticosterone pellets designed to approximately double the baseline corticosterone levels. Corticosterone–implanted birds cached and consumed significantly more food and showed more efficient cache recovery and superior spatial memory performance compared with placebo–implanted birds. Thus, contrary to prevailing assumptions, long–term moderate elevations of corticosterone appear to enhance spatial memory in food–caching mountain chickadees. These results suggest that moderate chronic elevation of corticosterone may serve as an adaptation to unpredictable environments by facilitating feeding and food–caching behaviour and by improving cache–retrieval efficiency in food–caching birds.

References

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Consensus Conference Panel:, Watson, N.F., Badr, M.S., Belenky, G., Bliwise, D.L., Buxton, O.M., Buysse, D., Dinges, D.F., Gangwisch, J., Grandner, M.A. and Kushida, C., 2015. Joint consensus statement of the American Academy of Sleep Medicine and Sleep Research Society on the recommended amount of sleep for a healthy adult: methodology and discussion. Journal of Clinical Sleep Medicine, 11(8), pp.931-952.

Eckert A, Karen S, Beck J, Brand S, Hemmeter U, Hatzinger M, Holsboer-Trachsler E. The link between sleep, stress and BDNF. European Psychiatry. 2017 Apr;41(S1):S282-.

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Goldschmied JR, Rao H, Dinges D, Goel N, Detre JA, Basner M, Sheline YI, Thase ME, Gehrman PR. 0886 Recovery Sleep Significantly Decreases BDNF In Major Depression Following Therapeutic Sleep Deprivation. Sleep. 2019 Apr;42(Supplement_1):A356-.

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104 comments

Comments sorted by top scores.

comment by ChristianKl · 2022-02-11T13:55:06.994Z · LW(p) · GW(p)

It's been a while since I looked into Stampi, but from what I remember Claudio Stampi optimizes for the performance during a race and makes statements about what's optimal for the race environment. As far as I remember Stampi does not advocate that the sailors go down to those low amounts of sleep outside of their racing conditions. In most sports, the behavior that's optimal for maximum sports performance is not the behavior that's optimal for long-term health. 

comment by PeterMcCluskey · 2022-02-12T04:00:57.908Z · LW(p) · GW(p)

I'm unsure what to make of your main points.

Your description of sleep 10,000+ years ago is a bit misleading. My backpacking experience tells me that it doesn't take too long to learn to sleep comfortably on unpadded ground. It doesn't take modern technology to deal with cold well enough to sleep comfortably - I suspect modern people have more trouble, because they keep their bedrooms at daytime temperatures (i.e. too warm).

If it was harder to sleep in the past, it's primarily because of dangers. I presume this was quite variable. This article on ancestral sleeping postures mentions constraints on sleep posture due to insects, lions, and human enemies. The larger threats seem to be handled by having someone awake at any given time. Crawling insects were handled via grass beds. I'm puzzled as to how flying insects impacted sleep. I've had problems with them while sleeping outdoors, but I think they mostly go away in the middle of the night?

Replies from: yair-halberstadt, meedstrom, velcro
comment by Yair Halberstadt (yair-halberstadt) · 2022-02-22T08:15:14.494Z · LW(p) · GW(p)

I would even argue that historically it's quite likely we got more sleep. When backpacking I'll go to sleep at sundown and wake up at sunrise. The first few days I'll sleep badly, but after that I'll sleep fine throughout.

Even in the height of summer, where I live there's still 9 hours of darkness. So I never get as much sleep as when I'm backpacking. And since I'm exercising all day I sleep really soundly.

Replies from: AllAmericanBreakfast
comment by DirectedEvolution (AllAmericanBreakfast) · 2022-02-22T16:44:49.035Z · LW(p) · GW(p)

Keep in mind, though, that diet, exercise, cognitive/work demands, stress, and social patterns may impact your sleep needs. And backpacking isn’t necessarily representative of a hunter-gatherer lifestyle in any of these aspects.

Replies from: yair-halberstadt
comment by Yair Halberstadt (yair-halberstadt) · 2022-02-22T17:12:01.496Z · LW(p) · GW(p)

That's true but the point is we just don't know if our ancestors got more or less sleep than us, whereas we know a fair amount about hunter gatherer diets.

Replies from: AllAmericanBreakfast
comment by DirectedEvolution (AllAmericanBreakfast) · 2022-02-22T17:48:31.646Z · LW(p) · GW(p)

I agree, but I'm arguing that there's a temptation, which we should resist, to assume that our closest personally-experienced approximation to a hunter-gatherer lifestyle (backpacking) is a close approximation.

comment by meedstrom · 2022-02-13T02:53:59.207Z · LW(p) · GW(p)

On the issue of flying insects, the people who do "cowboy camping" (sleeping without a tent) have relevant experience. They recommend finding high ground far away from any lake, because still bodies of water attract bugs.

comment by velcro · 2022-02-22T12:41:53.472Z · LW(p) · GW(p)

In equatorial Africa, I assume it is quite dark for 10-11 hours every single night where there is no moon.

comment by Natália (Natália Mendonça) · 2022-02-14T00:05:47.101Z · LW(p) · GW(p)

I wrote large chunks of this essay having slept less than 1.5 hours over a period of 38 hours. I came up with and developed the biggest arguments of it when I slept an average of 5 hours 39 minutes per day over the preceding 14 days. At this point, I’m pretty sure that the entire “not sleeping ‘enough’ makes you stupid” is a 100% psyop. It makes you somewhat more sleepy, yes. More stupid, no. I literally did an experiment in which I tried to find changes in my cognitive ability after sleeping 4 hours a day for 12-14 days, I couldn’t find any. My friends who I was talking to a lot during the experiment simply didn’t notice anything.

I find it implausible that your anecdotes and a non-RCT N=1 self-experiment provide stronger evidence than several N≈20 non-pre-registered RCTs. 

Yes, p-hacking and lack of pre-registration are bad, but IMO those things are pretty much negligible concerns when studies test cognition with several tests and find the same effect on almost all of them

When I read the literature on the cognitive effects of sleep deprivation, it doesn't sound like experimenters are giving subjects several tests, finding no effect on most of them, and then focusing on reporting the single p<0.05 result. Rather, they find medium-to-large effect sizes on most things they test, and effect sizes almost always have the same sign -- very rarely favoring sleep deprivation. That could be because the experimenters are giving subjects 15 tests and only report the results of 5 of them, but it sounds unlikely that all sleep researchers involved in these studies are doing that. So it doesn't look like p-hacking or lack of pre-registration are driving the huge effect sizes here. 

It sounds a lot more plausible that an N=1 self-experiment has fatal flaws to it, especially if the one study subject wants the results to come out a certain way.

 

ETA: I no longer endorse the fact that I linked to that specific meta-analysis. See my new post [LW · GW] for a better investigation of the effects of sleep restriction on cognition. 

Replies from: AllAmericanBreakfast, AllAmericanBreakfast, TLW
comment by DirectedEvolution (AllAmericanBreakfast) · 2022-02-23T07:28:52.575Z · LW(p) · GW(p)

I want to emphasize that I agree that we ought to prefer study data to N=1 motivated self-experiment, and I appreciate you bringing this meta-analysis to the table.

Now, let's take a close look at Pilcher and Huffcutt.

Guzey's self-administered study would be coded by P&H as "partial sleep deprivation" (< 5 hours sleep in a 24 hour period), the group showing the largest negative effect sizes in P&H. Note, however, that P&H are aggregating results from just 6 studies (citation numbers 39-41,44,48,49).

The experimental groups of these 6 studies included:

  • Anesthesia residents after 24 hours of in-house call.
  • Medical interns at work.
  • Periodic testing of graduate students at a psychological research center over 8 months, while the students lived an otherwise normal life.
  • Soldiers on an 8-day field artillery trial manually handling a large quantity of artillery shells (weighing 45 kg) and charges (13 kg).
  • Surgical resident's who've been up working all night.
  • Internal medicine residents after a night on call.

In all but the trial on the graduate students, the subjects were dealing with both sleep deprivation and work-related fatigue. Guzey's specifically interested in sleep deprivation per se, rather than the effects of work-related fatigue. Note that in the (n=8) study of the graduate students, "It was concluded that 6-8 months of gradual sleep restriction, down to 4.5-5.5 hrs per night, does not result in behavioral effects measurable by the instruments used... At the end of an additional 12-month follow-up period, total sleep time was still 1-2.5 hrs below baseline, but measures of well-being had returned to baseline levels."

How could we get such clear and obvious results from the fatigue studies on doctors, and see nothing in the graduate students? I think work-related fatigue in the hospital is the culprit.

In addition, the inclusion of the soldier study is inexplicable. It wasn't a study of sleep loss, but of the impact of sustained manual labor on muscular strength and endurance. The control and experimental group had no statistically significant differences in sleep deprivation, though both were sleep-deprived. I can only interpret the meta-study as using the effect of sustained manual labor under (uniform) conditions of sleep deprivation as a proxy for the effects of sleep deprivation itself.

Here's an outline of the study itself. Group A sleeps 4 hours per night and loads artillery shells, group B sleeps 4 hours per night and doesn't load any artillery shells. When Group A experiences a greater loss in muscular strength and endurance than Group B after 8 days of this regimen, the sleep researchers interpret this as the result of the sleep deprivation (which was identical to Group B's), rather than the manual labor (the actual experimental intervention). So that makes no sense. Rather than inexplicable, perhaps I should have said inexcusable.

Considering the undoubtedly important confounding from the intense work environments of the subjects and that one of the six studies in this wing of the meta-analysis doesn't belong there at all, I think this meta-analysis cannot shed as much light on Guzey's research question as we might hope. In fact, the most useful part is the study of the graduate students, as it's likely the least confounded by the effects of a high-stress and taxing work environment. It's this one that finds effects that match Guzey's claim.

All this is to highlight the importance of the specific research question and methods. Fatigue from working in a stressful or physically demanding environment is not the same thing as the effects of sleep deprivation. If we are interested in the latter, we should not permit the former to confound our study. This isn't meant as an attack on you at all, but I think that the impulse to use the results of a meta-study of "sleep deprivation" that is actually a meta-study of work-related fatigue in a high-stress environment with 1/6 erroneous inclusions is indicative of the problems Guzey's highlighting in his overall interpretation and critique of sleep studies.

Replies from: ChristianKl
comment by ChristianKl · 2022-02-23T09:40:26.420Z · LW(p) · GW(p)

As a meta point, the fact that a journal in the field is willing to publish such a meta-study that draws misleading conclusions is evidence for Guzey's claim that the field is cargo-culting and not trustworthy. 

comment by DirectedEvolution (AllAmericanBreakfast) · 2022-02-23T05:37:30.359Z · LW(p) · GW(p)

Your first ("huge") and third ("sizes") links are broken.

comment by TLW · 2022-02-14T02:46:28.874Z · LW(p) · GW(p)

A measurement showing a correlation (or lack thereof) in the population does not exclude other correlations in subsets of the population.

comment by DirectedEvolution (AllAmericanBreakfast) · 2022-02-22T07:24:17.224Z · LW(p) · GW(p)

I did a little epistemic spot checking:

  • Read the memory consolidation review article
  • Browsed two pages of Googe Scholar abstracts for the search "cancer risk sleep duration"
  • Looked at the abstract of the epidemiological study Guzey cites against the cancer/sleep deprivation
  • Googled for "world health organisation sleep epidemic"

So far, all of Guzey's specific claims about incorrect statements by Walker have held up. That epidemiological study on sleep duration and cancer risk? Not cherry-picked. If you look at the other two pages of cancer risk/sleep duration studies, hazard ratios are typically small (though one is around 1.6, IIRC). Some show elevated cancer risk for longer-duration sleep (on the order of 10 hours). Most show little-no effect, though some that show no effect in aggregate find subgroup effects.

I feel unbelievably stupid saying this, but the format of Guzey's takedown post, and this post even moreso, have a style and format that makes me particularly nervous. Maybe it's the font. If I bought the argument, then I might want to show it to other people, who'd see a very long and strongly worded blog post with LOTS OF BOLD AND UNDERLINE with Twitter inclusions totally taking down one of the world's leading sleep researchers (while working on 1.5 hours of sleep)! I expect they'd see me as credulous and not consider it more deeply (possibly because they'd imagine the same result in showing Guzey's posts to their friends).

When I found him referenced by a sympathetic author in Prospect Magazine, the sort of publication I might not feel embarrassed to send to my parents, it made me feel more open to Guzey's argument. And yes, I would probably share the Prospect Magazine article before I shared Guzey's post. There's a time for symmetric weapons. But Guzey gets the moral credit for raising the issue.

Replies from: guzey, FinalFormal2
comment by guzey · 2022-02-22T19:44:44.254Z · LW(p) · GW(p)

lmao I started reading this comment and was like "oh no i'm about to be destroyed" and instead everything held up 😎

 

I guess showing drafts to literal dozens of people before publishing actually works haha.

Replies from: AllAmericanBreakfast
comment by DirectedEvolution (AllAmericanBreakfast) · 2022-02-22T23:20:04.787Z · LW(p) · GW(p)

Peer review, baby! Sorry for scaring you, I've suspected for a while that my writing can come off as intimidating, but I haven't figured out yet how to solve that problem. Thanks for the feedback ;)

comment by FinalFormal2 · 2022-02-27T20:11:08.224Z · LW(p) · GW(p)

He alleges a psyop. It's alright to feel nervous about the content.

comment by Jacob Pfau (jacob-pfau) · 2022-02-12T16:43:34.124Z · LW(p) · GW(p)

Here's one way of thinking about sleep which seems compatible with both the less-sleep-needed thesis and the lower-productivity-while-deprived observation: Some minimal amount of sleep provides a metabolic / cognitive role, and beyond this amount, additional hours of sleep were useful in the evolutionary context to save calories when the additional wakeful hours would not provide pay off.

If true, we'd expect there to a more-or-less fixed function from sleep quantity to sleepiness within the very low sleep range, but in the mid-sleep (5-8 hr?) range this function from quantity to sleepiness would be entirely mediated by stimulation. Stimulation here could mean physical exercise, but I expect excitement / anticipation are also very relevant -- in an evolutionary context such feelings signal higher payoff for wakefulness.

The importance of such a perspective, is that reducing sleep quantity would be possible only conditional on the upstream stimulation/excitement variable. Elon, Guzey, highly motivated or active people would all have an easier time avoiding unpleasant struggles to overcome sleepiness. If you are not highly motivated / excited by a given day's activities there are a few possible implications: 1) simply assume greater sleepiness and give up on economising sleep 2) you could try intermittent physical exercise e.g. periodically doing some squats 3) you could deliberately schedule things which you find exciting / something for late in the day to generate anticipation.

I would be interested to see data on this idea, either by testing strategies (2) and (3) in a psychological study, or by comparing sleep patterns in hunter societies as they vary across time (as a function of hunting opportunity). I think there's already decent support for this explanation, since it explains the discrepancy between the Elon/Guzey/Sailors anecdata and the fact that most people aren't happy about missing two hours of sleep. The story also seems to fit well with the depression-treatment result. To make this point clear, one way of putting things is that there's some excitement/looking-forwardness state which overlaps with the low-sleep state.

comment by Elizabeth (pktechgirl) · 2022-02-11T20:14:48.740Z · LW(p) · GW(p)

I'm not sold on the conclusions right now but I think this raises a number of excellent points (particularly the analogy with fasting) and I'm really looking forward to an extended discussion of it.

Replies from: Jackson Wagner, AllAmericanBreakfast
comment by Jackson Wagner · 2022-02-13T22:45:42.201Z · LW(p) · GW(p)

The fasting analogy is interesting, as is the analogy with exercise -- some kinds of activities are beneficial in the long-run even when they are damaging/unpleasant in the short run.  But surely these are exceptions to the general rule, right?

  • Besides exercise, it's not good to repeatedly injure yourself and then have the wounds heal.  (Exercise is essentially the small, specific subtype of "injury" which is actually good for the body in the long term.)
  • Getting sick with a cold or flu is good at building immunity to that kind of virus when it comes around a second time, but aside from immunity concerns, it would be better for your health to never become sick at all.  (As with viruses, the same goes for diseases caused by parasites or bacteria.)  Especially as a young child, getting badly sick can impact your development and later IQ / income / etc substantially.  Getting mildly sick is probably mildly bad for those same metrics.
  • On the other hand, I enjoyed your post a few months ago examining whether letting kids play outside and get dirty is helpful for calibrating their immune systems and reducing allergies later in life [LW · GW].  It seems like the "hygiene hypothesis" is less firmly established than I thought, but if true it would be an example something else like exercise and fasting where injury/stress leads to long-term benefit.
  • One of the reasons junk food is bad is because it has lots of quickly-absorbed sugars, which rush into your bloodstream and force your insulin/glycogen system to ramp up quickly and do a lot of work.  Over the long term, putting all this stress on your body's ability to absorb sugars is though to reduce your body's insulin sensitivity, leading to metabolic disorders like prediabetes.  So, chronic consumption of junk food is bad -- but should I prefer a totally healthy "low-glycemic index" diet?  Or a mostly low-glycemic index diet but I occasionally consume a blast of sugary sweets to "exercise" my insulin system?  I don't think science has given us a real answer here, but most doctors would probably recoil in horror at the idea of "exercising" one's metabolic system by occasionally binging junk food, and I'd be inclined to agree with them.
  • Some kinds of psychological stress and trauma are probably beneficial in the long run (for instance, working hard on a project to meet a deadline and feeling invigorated + learning better productivity skills as a result), while other kinds are probably just bad.

Basically, it seems like there are plenty of examples on both sides, and I can't figure out any general rule that would let me predict ahead of time which seemingly-bad behaviors/stressors are secretly good or not.  The examples of exercise and fasting are helpful reminders to keep an open mind, but I don't think they can tell us much more than that when we're trying to figure out how to think about sleep.

(Similarly, some things about the modern world are "superstimulus" -- like junk food.  But others are just progress -- like the fact that I can afford a healthy diet with lots of meat and vegetables if I so choose, while my agrarian ancestors got much more of their calories from samey, not-very-nutritious grains.  I don't know if comfortable beds are a superstimulus encouraging us to oversleep harmfully or just modern progress enabling us to higher-quality sleep.  But I do appreciate that the "superstimulus" hypothesis is reasonable and encourages us to keep an open mind.)

Replies from: pktechgirl, martin-randall
comment by Elizabeth (pktechgirl) · 2022-02-14T04:20:16.507Z · LW(p) · GW(p)

I am much more sold on "variety is good for humans, and mild-moderate deprivation and excess is variety" than "humans should permanently run on much less sleep than they think they need" or "sleepiness is a lie".

One tricky thing here is humans aren't actually guaranteed to have a pareto optimim, or to have a path that gets all good things. It seems really plausible childhood illnesses damages development and IQ, and lack of childhood illness causes allergies and immune vulnerability later (I think think the hygiene/old friends hypothesis is largely correct, even if it doesn't support eating dirt in particular), and there isn't an ideal level that gets you your max IQ and no allergies. Variety is something of a hack to get some of both and also create a discovery process for what you need more at a particular moment.

comment by Martin Randall (martin-randall) · 2022-02-14T02:34:40.673Z · LW(p) · GW(p)

Most doctors would probably recoil in horror at the idea of "exercising" one's metabolic system by occasionally binging junk food, and I'd be inclined to agree with them.

In the US, pregnant women get a glucose tolerance test to check for gestational diabetes, which involves drinking 100g of glucose on an empty stomach and seeing how quickly it gets processed. But that's once or twice per pregnancy.

comment by DirectedEvolution (AllAmericanBreakfast) · 2022-02-22T17:05:51.169Z · LW(p) · GW(p)

The most valuable contribution of the OP for me was in breaking down “sleep research” into more fine-grained hypotheses.

Does sleeping X hours per night cause an increase in [specific physical or mental health risk]?

A need for a different word for “the physiological states and dynamics associated with various sleep stages” as opposed to the psychological experience of being asleep. Let’s call these “physical sleep” vs “sleep experiences.” Also, we may want to introduce a category of “stimulating experiences” vs “non-stimulating experiences,” the latter of which includes sleep, meditation, perhaps a stroll around the park.

The possibility of interventions that control or reproduce any downstream impacts of physical sleep or sleep experiences on mortality/injury, cognition, and awake experiences (ie meditation as substitute for sleep experiences in memory consolidation).

The possibility that it is in fact non stimulating experiences that are neglected in our culture, and that our understanding of these dynamics is so poor that we uniquely assign their benefits to sleep.

As an analogy, maybe sleep is like lemons, and what we need is vitamin C. Our culture currently assumes there’s a unique power in lemons that can be found nowhere else in nature, but also that anything that we call “lemon juice” (lime juice, lemon juice piped through copper tubing) will give at least some of the benefits. This despite reports from polar explorers that bear liver replicates the effects just as well, but they’re weird crazy polar explorers and the admiral of the navy says limes are fine.

I think Guzey should also look into Buddhist monks, another group who habitually get less than 8 hours of sleep and are highly involved with non stimulating and transcendent experiences. It’s actually interesting to me that so little of the chatter around meditation and enlightenment addresses the role of low-sleep regimens in this context. I’d be curious to learn more.

Replies from: pktechgirl
comment by Elizabeth (pktechgirl) · 2022-02-22T18:31:49.432Z · LW(p) · GW(p)

Oh man this is so much better than my curation notice.

Replies from: AllAmericanBreakfast, Torello
comment by DirectedEvolution (AllAmericanBreakfast) · 2022-02-22T19:13:05.237Z · LW(p) · GW(p)

I may well have skipped this if it wasn’t for your curation notice. I take your judgment on what’s worth reading pretty seriously!

Replies from: pktechgirl
comment by Elizabeth (pktechgirl) · 2022-02-22T19:26:20.630Z · LW(p) · GW(p)

neat, sounds like a success story all around.

comment by Torello · 2022-03-04T01:59:50.551Z · LW(p) · GW(p)

What's a curation notice?

Replies from: Raemon
comment by Raemon · 2022-03-04T02:02:26.234Z · LW(p) · GW(p)

It's a comment indicating that a moderator has curated something:

https://www.lesswrong.com/posts/HvcZmKS43SLCbJvRb/theses-on-sleep?commentId=hMvSncYmxMukMJm4s [LW(p) · GW(p)] 

comment by Elizabeth (pktechgirl) · 2022-02-21T22:45:32.131Z · LW(p) · GW(p)

Curation notice: I'm far from sold on the specific conclusions of this piece (discussed more here [LW · GW], EDIT: and by AllAmericanBreakfast below), but I'm really excited to see the combination of strongly grounded criticisms of existing work, new hypotheses, and serious experimentation to test those hypotheses. In my ideal world this leads to more people running experiments that produce useful object-level data and a better approach for those experiments, which can be scaled (e.g. how do you measure cognitive abilities over a year, reliably and with minimal time costs), and eventually leads to a better understanding of sleep and how a given person should optimize for their goals.

comment by velcro · 2022-02-22T12:56:14.619Z · LW(p) · GW(p)

I see some basic flaws in the sleep-exercise and sleep-food analogies.

There are reasonably well-understood physiological mechanisms showing how slight overuse of muscles starts a process of strengthening those muscles.  I did not see any proposed mechanism for less sleep reducing your need for sleep.  (If I missed it, please let me know).  While it is true of lots of inputs (food, oxygen) I do not think it is defensible to arbitrarily generalize the idea that reduction of any input allows you to function with less of that input.

With the food analogy specifically, there is a much different element of control.  I can sit in front of a delicious meal at any time and abstain, even if my body is "telling" me I am starving, or I can eat garbage if my body is "telling me" I am not hungry.  I can't do that with sleep without chemical help, except perhaps delay sleeping for a few hours or sleep a few hours late.  My conclusion is that I sleep when my body needs sleep.  If I go to bed and 9 hours later wake up naturally, I needed the 9 hours.

Of course, if I wake up and have nothing to do, and decide to stay in bed for another hour, that does not mean my body needed 10 hours.  But the 9 hours I had no conscious control over? Yup, my body did what it needed to do.

Replies from: AllAmericanBreakfast, ChristianKl, someflowLT
comment by DirectedEvolution (AllAmericanBreakfast) · 2022-02-22T23:18:58.325Z · LW(p) · GW(p)

My conclusion is that I sleep when my body needs sleep.  If I go to bed and 9 hours later wake up naturally, I needed the 9 hours.

I think the right conclusion is that you sleep when your body compels sleep, and that your body has a greater ability to compel sleep than it has to compel eating. You have identified your body's needs with its ability to compel your acquiescence.

This is plausible: we might expect that evolution would equip us with urges in proportion to their importance for survival and reproduction. But we also know that we're subject to a wide array of dysfunctional compulsions, including drugs, gambling, and anger management problems.

Furthermore, some strong urges serve purposes that aren't apparent. If you spontaneously start to vomit because of something you ate 6-24 hours earlier, you won't immediately know which food item triggered the vomiting. Moreover, the vomiting itself is not "what your body needs." Intead, it's the clearance of the toxin. A person with a chronic vomiting problem, or let's say migraine headaches, doesn't tend to interpret the strong urges to puke or avoid light as "what their body needs," but as a symptom of a health disorder.

This isn't to say that the need to sleep is the symptom of a health disorder. Instead, it's to say that we have a pretty hazy notion of where to put the dividing line between urges and needs, or healthy/enjoyable/excessive/dysfunctional sleep. At least one book has been written seriously arguing for responsible heroin use.

As far as I'm concerned, you can put the dividing line for your own sleep wherever it seems right to you. But if we're talking about the scientific study of sleep, as Guzey and Matthew Walker are, it's no longer epistemically permissible to base that decision on one's personal opinion.

Why might we care to go beyond personal opinion? Consider the analogy of scurvy. A sailor with scurvy doesn't feel any strong urge to eat Vitamin C pills or suck on a lemon. But it's a very particular vitamin deficiency they're experiencing, and it's the careful study of why lemons and liver prevent and cure scurvy that allows us to get to the heart of the matter. In the time in between the realization that citrus was associated with scurvy prevention, there were a lot of misapplied interventions. It was assumed that the sourness was responsible for scurvy prevention, so sailors were given ineffective limes rather than effective lemons. The juice was piped through copper tubing that destroyed the vitamin and the benefit. The knowledge itself was gained and lost by the naval authorities of the time, even as changes in sailing times decreased scurvy incidence for reasons unrelated to sailor diet.

I for one am happy to know that vitamin C cures scurvy, even though I happen to live in a dietary environment that reliably supplies me with an adequate dose without me needing to ever think about it. I happen to know that folic acid is not routinely added to the maize used by Latino Americans, and for this reason, that community suffers elevated rates of entirely preventable neural tube birth defects. I very much wish that we'd start putting folic acid in maize. But it's our knowledge of that scientific connection that allows us to conceive of this intervention in the first place.

Developing an equivalent understanding of the mechanistic functions of sleep seems to me a valuable contribution to scientific knowledge, one that could offer equivalent benefits to human health. At the current time, it seems to me that our understanding in this area is approximately equivalent at best to the British Navy's early understanding that sour-tasting fruit helps with scurvy. The brain scan data is sort of like having really good anatomical depictions of what healthy and diseased gums look like. As far as I know, we don't know how we get from sleep to alertness, cognition, or health, or from sleep dysfunction to things like depression or mania, or even what sort of weird compounded things are contained within the sleep-lemon.

comment by ChristianKl · 2022-02-22T15:57:53.468Z · LW(p) · GW(p)

I did not see any proposed mechanism for less sleep reducing your need for sleep.  (If I missed it, please let me know).  

We lack a good idea of why the need for sleep exists in the first place. 

If we sleep because there was little to do 100,000 years ago when it's dark outside and we want to reserve energy, it makes sense to modulate to have a mechanism that modulates the amount of sleep so that people sleep more when it's dark outside for longer.

I can't do that with sleep without chemical help, except perhaps delay sleeping for a few hours or sleep a few hours late.  

That's not true. Humans are capable to set intentions to wake up at certain times and wake up at that time. You might personally not have conscious access to the underlying processes the same way you can avoid eating but that doesn't mean that they aren't there.

Replies from: guzey
comment by guzey · 2022-02-22T20:15:03.053Z · LW(p) · GW(p)

Yep, I sometimes manage to ask my body to wake up at a certain time and it does it when there's something I care a ton about waking me up a few minutes before the alarm.

comment by someflowLT · 2022-02-27T04:07:04.429Z · LW(p) · GW(p)

This was my thought as well. The problem with candy being a superstimulus is that each time I walk past it in the kitchen I have to exercise willpower to not eat it.  While I'm asleep, the reason that I remain asleep is certainly not because I'm somehow giving in to temptation.  So the analogy doesn't work for me.  

I do agree w/ Guzey that "sleepiness, like hunger, is normal".  If I'm not feeling tired I stay up.  

If anything, the same analogy applied to my personal experience would tell me that ~7 hours of sleep IS normal.  For me the analogy looks like: 

I only eat when I'm hungry; I eat until I'm satisfied.  I'm healthy and not gaining weight. 

I only sleep when I'm tired; I sleep until I'm rested.  I sleep 7-8 hours on average and am happy with my energy levels.  

comment by Elizabeth (pktechgirl) · 2023-12-05T04:56:15.478Z · LW(p) · GW(p)

Guzey substantially retracted this a year later. I think it would be great to publish both together as a case study of self-experimentation, but would be against publishing this on its own. 

Get minimum possible sustainable amount of sleep -> get enough sleep to have maximum energy during the day

Sleep makes me angry. I mean, why on Earth do I have to spend hours every day lying around unconscious?????????

In 2019, trying to learn about the science behind sleep I read Why We Sleep and got so angry at it for being essentially pseudoscience that I spent >100 hours debunking it. In 2020, I slept 4 h/day for 2 weeks and shown that this didn’t make me dumber (not recommended, it was terrible). In 2022, I published Theses on Sleep, with points like “Experiencing sleepiness is normal and does not necessarily imply that you are undersleeping. Never being sleepy means you are probably sleeping too much.”

What I changed my mind about

1. There’s no good medical reason to sleep more than the minimum you can sustain.

Not this one! Fight me.

2. I can sleep 4h/day, so 6h/day must be easy.

It turns out that sleeping 6h/day is hard… I have to track sleep & adjust for every party I go to, deadline, travel; worry about sleepiness during boring meetings/tasks; etc.

3. It’s fine to sometimes be sleepy.

I tried Adderall and it made me more awake than ever before. I noticed that this made me want to do stuff more, pay more attention, be more intentional, think quicker, have more ideas, and remember more. Conversely, I started to notice that being sleepy has the exact opposite effect.

Therefore, I realized that it’s very important to be as awake as possible and that my model of sleepiness where you can be “awake”, “sleepy” and “asleep” is dumb.

4. I don’t have another 10h/week to spend being dead.

Come on 2022 Alexey, you definitely lose >10h/week to just random bullshit. Ahem, CS:GO.

5. Many impressive people sleep 5-6h (Elon, Napoleon, Thatcher), so I can too.

Sure. And many others (Bezos, Zuck, Isaak Freeman) sleep 7-8h.

What I do now

  1. I default to sleeping 2300-0600. I do my best to always wake up at the same time because I wake up 10-15m before the alarm if I do this for several days in a row.
  2. I don’t worry about sleeping 3-4h occasionally. I’m actually writing this at 4am after <3 hours of sleep. But I avoid doing this often because it messes up my schedule.
comment by Alicorn · 2022-02-12T06:53:01.292Z · LW(p) · GW(p)

This post is very interesting and I'm excited to hear back from anyone who is going to experiment based on it.  My experience with sleep deprivation is mostly centered around having children; my functioning is unquestionably impacted by that kind of fragmented and reduced sleep (especially emotionally) but maybe a solid yet shorter period of sleep would actually be fine.  The trouble is I'm not sure how I'd check... because I've found that if I have an alarm set to go off in the morning, not only is it in itself staggeringly unpleasant, it makes me anxious enough that I sleep very poorly the night before.  I've gone to a lot of effort to (kids and all) arrange that I can sleep in as late as feels right.

Replies from: guzey
comment by guzey · 2022-02-12T09:48:22.992Z · LW(p) · GW(p)

Hmm, we seem to have very different subjective experiences around sleep. While I'm sure that I would also feel bad if my sleep was disrupted at random periods, I have no issue with alarms and I feel like I sleep better with an alarm, knowing that I will not just sleep through everything I wanted to do in the morning...

Replies from: meedstrom
comment by meedstrom · 2022-02-13T03:03:35.733Z · LW(p) · GW(p)

I'm like Alicorn, with the addition that I love disruption at random periods, because it lets me fall asleep again: pure pleasure.

comment by bfinn · 2022-03-01T22:10:28.728Z · LW(p) · GW(p)

I had sleep problems all my adult life, which I eventually found were due to sleeping too much (or more accurately, thinking I should get 8 hours' sleep, and thus allowing too much time to sleep in).

I conducted an experiment on myself over several months using 21 different factors claimed by the literature to affect sleep. None of them helped. (Though a few of the factors I was doing anyway, e.g. having a comfortable mattress & pillow, so weren't worth varying; and several made sleep worse for obvious reasons, e.g. stress & illness, but weren't things I could actively improve.)

However, I then tried a (very good) online sleep course at www.sleepio.com, which among other things got me to try various adjustments to my sleep hours. This revealed something I hadn't considered - viz. I'd always assumed I should ideally be getting 8 hours' sleep. So I was allowing too much time to sleep in, producing shallow sleep, and waking up often in the night. The web site made me gradually shrink my sleep time so I slept shorter but deeper, until I stopped waking up in the night. It also helped by making me establish a regular wake time.

As a result, I went from getting a full night's sleep just once a year, to almost every night. And also wasted less time in bed, either lying awake or snoozing.

I did a talk about all this, which is here. E.g. it goes through the 21 factors, which people may find useful.

Replies from: bfinn
comment by bfinn · 2022-06-22T19:59:33.870Z · LW(p) · GW(p)

I heard recently that sleepio is now prescribed by the UK's National Health Service, so has presumably been clinically demonstrated to be very effective.

comment by Andrew Vlahos (andrew-vlahos) · 2022-02-22T23:57:20.415Z · LW(p) · GW(p)

I'm a tutor, and I've noticed that when students get less sleep they make many more minor mistakes (like dropping a negative sign) and don't learn as well. This effect is strong enough that for a couple of students I started guessing how much sleep they got the last couple days at the end of sessions, asked them, and was almost always right. Also, I've tried at one point going on a significantly reduced sleep schedule with a consistent wakeup time, and effectiveness collapsed. I soon burned out and had to spend most of a day napping to catch up on sleep.

At this point I do think enough sleep is important, and have a different hypothesis that needed sleep is just different for different people. 

Replies from: NormanPerlmutter, guzey
comment by NormanPerlmutter · 2022-02-23T07:29:03.735Z · LW(p) · GW(p)

Anecdotal, but similar -- when I used to play in chess tournaments, I had a sense that I performed better and made fewer errors when I had more sleep, to the point of aiming for 9 or so hours of sleep the night before a tournament.

comment by guzey · 2022-02-23T10:02:24.959Z · LW(p) · GW(p)

Yep, if someone was majorly undersleeping for a few days, they are probably going to be more sleepy and make more mistakes of attention/find it more difficult to concentrate and absorb the kind of information that they would need a tutor to absorb!

As an experiment -- you can ask a couple of your students to take a coffee heading to you when they are underslept and see if they continue to make mistakes and learn poorly (in which case it's the lack of sleep per se likely causing problems) or not (in which case it's sleepiness)

comment by Andy_McKenzie · 2022-02-11T20:02:45.345Z · LW(p) · GW(p)

Extremely interesting article with a number of good points! 

Is there any chance that you could expand upon the driving objection? Why, in your model of sleep and the cognitive effects of sleep, does getting little sleep increase your risk of getting into a car accident when driving?

Another point: I find Mendelian randomization studies fairly convincing for the long-term effects of sleep. For example, here's one based on UK Biobank data suggesting that sleep traits do not have an interaction with Alzheimer's disease risk: https://academic.oup.com/ije/article/50/3/817/5956327

Replies from: guzey, Morpheus
comment by guzey · 2022-02-12T09:40:05.079Z · LW(p) · GW(p)

I wrote:

 I agree that driving while being sleepy is dangerous and I don’t want anyone to drive, to operate heavy machinery, etc. when they are sleepy.

Driving simply seems to be a monotonous task of the exact kind where falling asleep even for a few seconds is very dangerous, thus driving while being sleepy is dangerous

Replies from: Andy_McKenzie
comment by Andy_McKenzie · 2022-02-12T14:19:32.845Z · LW(p) · GW(p)

Makes sense! I guess I wonder if there’s a literature on the cause of sleep deprivation induced car accidents, eg whether the problem is only microsleeps or whether things like impulsivity or reaction time also contribute.

ETA: Preliminary search: the first Google result found this study: https://bmcpublichealth.biomedcentral.com/articles/10.1186/s12889-020-09095-5

Basically, in these driving simulations, reaction time and breaking time is significantly affected by sleep deprivation. I’m not sure how this could all be due to microsleeps. And it seems quite plausibly related to both risk of car accident and cognitive performance more broadly.

Replies from: Vaniver
comment by Vaniver · 2022-02-22T03:53:19.141Z · LW(p) · GW(p)

whether the problem is only microsleeps or whether things like impulsivity or reaction time also contribute.

There's a thing called the Psychomotor Vigilance Task, which when I did it during a sleep deprivation experiment (ten years ago) showed both an increase in reaction time and increase in 'lapses' (not responding to the light quickly enough). I suspect that worse reaction time would contribute significantly (note that responding to things later means you need to respond to them more harshly, which causes problems of its own).

comment by Morpheus · 2022-02-12T02:10:00.635Z · LW(p) · GW(p)

Why, in your model of sleep and the cognitive effects of sleep, does getting little sleep increase your risk of getting into a car accident when driving?

I Interpreted him as not explicitly stating that lack of sleep is dangerous when driving, but feeling sleepy:

Yep, I agree that driving while being sleepy is dangerous and I don’t want anyone to drive, to operate heavy machinery, etc. when they are sleepy. This, however, bears no relationship on any of the arguments I make.

But after reading the quoted section again I feel like "being sleepy" is ambiguous and your Interpretation might be valid.

comment by Jackson Wagner · 2022-02-14T00:31:27.275Z · LW(p) · GW(p)

Hello Guzey!  Your blog and your new organization are a big inspiration to me.  I greatly enjoyed this post; here is a grab-bag of thoughts which hopefully contains some useful info for you:

  • You might be interested to learn that some corners of Buddhism sometimes seem to have a strong anti-sleepiness agenda:
  • How are you measuring sleep hours?  Are you talking about time in bed or time asleep as measured by a device like a fitbit?  Even though I think of myself as someone who falls asleep easily, the time it takes for me to fall asleep + some tossing and turning during the night + the time I spend lazing around in the morning + probably some inaccuracy on part of fitbit, means that my actual time asleep is usually about an hour less than my time in bed.  This measurement issue is important because it otherwise makes it hard to understand what people are reporting/recommending when they say things like "half of hunter-gatherers sleep less than 6 hours per day, and they're doing fine" or "it's important to get 8 hours of sleep every night".
  • Here are my biggest worries about potential downsides to chronically cutting back on sleep (the upside of course being an extra 1-2 hours awake every day, which is a strong benefit):
    • Am I really coming out ahead on lifespan?
      • Alzheimer's, heart health, susceptibility to disease, and other long-term health things.  Maybe exercise is less effective while sleep-deprived?  Or some other effect whereby I eventually lose the extra hours.
      • Accident risk from driving -- if I go about my day 10% drowsier, am I "picking up pennies in front of a steamroller"?
      • Is an hour of increased "effective lifespan" in my thirties worth more than an hour of extended "regular lifespan" in old age, or vice versa?  (This is a complex calculation IMO that depends on a lot of stuff.  I hope to write a detailed post about it someday.)
    • Am I undermining the quality of my life enough to outweigh the gain in quantity?
      • If I slept less, I would have to endure the unpleasant feeling of sleepiness more often, just like the feeling of hunger.
      • Other changes in consciousness besides the feeling of sleepiness.  In the morning I often feel more "fresh", happier, with more wide-field awareness and more in tune with my sensations.  My body feels healthier and more flexible.  During late evenings, I definitely often feel that narrow "amphetamine-like focus" and I'm able to get a lot done.  Sometimes I'm excited, sometimes stressed and miserable, but either way I feel like I am more beset by buzzing thoughts and less able to relax and enjoy a vivid experience of life.  (But some of this is probably not caused by sleepiness itself, but rather the structure of my day which proceeds from a new day full of potential to the end of a day when I am trying to finish tasks and tie up loose ends.)
      • Does sleep deprivation help or hurt my productivity?  (I've done a bit of self-experimentation here and discovered to my horror that I seem to get more work done while sleep deprived -- this was true even when I was working in the office 9-5, so it's not just an effect of late-night "amphetamine-like focus" nor of getting more done by spending more total hours awake.  But I suspect the causality might go the other way -- perhaps I got less sleep during periods when I was stressed and working hard.)  Perhaps sleep deprivation helps some types of productivity while hurting other less-visible aspects of productivity, like making me less creative or less good at prioritizing.
  • Rather than chronic sleep reduction, I feel more amenable to the idea that acute sleep deprivation might be good (or at least not so bad).  I would be interested in reading some detailed answers to questions like, "If I stay up late, to what extent should I set back my morning alarm (to avoid sleep deprivation), versus to what extent should I tough it out and then just go to bed earlier the next day?"  In your mind, how correlated are the likelihoods of your theses about chronic (the section "Decreasing sleep by 1-2 hours a night...") vs acute (Occasional acute sleep deprivation is good...") sleep reduction?  Do they both rise and fall together, or are they unrelated, or are they anticorrelated (such that finding out one claim was true would make you think maybe the other was false)?
  • Finally, what types of sleep studies would you be most interested in seeing going forwards?  Nowadays, fitbits and other devices can track sleep and sleep phases with reasonable accuracy.  So it seems like we should be about to enter a golden age of really being able to get answers to many of the questions you're raising.  But unlike with, say, Apple's "Heart and Movement Study" where you could hope to get information about the dose-response curve of exercise benefits as measured by heartrate and VO2max changes, many of the outcomes of interest with sleep seem hard to measure. (Alzheimer's risk or other super-long-term health hazards?  Productivity and happiness?)  So, if you had ten thousand fitbits and a big grant check to run whatever study you wanted, what design would you be most excited about?
comment by ChristianKl · 2022-02-11T22:22:03.652Z · LW(p) · GW(p)

In contrast, today: you sleep on your super-comfortable machine-crafted foam of the exact right firmness for you.

It sounds to me like you are saying that while the field of sleep science is quite shitty, the field of mattress design is very good. 

As a Westerner who's used to sleeping on a soft mattress sleeping on a hard floor is very uncomfortable but it's my impression that it feels better for people who aren't adapted to sleeping on mattresses.

If I have body awareness (my attention is not filled up with other things) I can relax better sitting on a hard floor than sitting on a soft couch.

comment by meedstrom · 2022-02-13T04:12:28.676Z · LW(p) · GW(p)

On the analogy with fasting,

Even if sleep works the way you suppose, this analogy looks like apples and oranges, so I don't like it.

With fasting, you can infer that it's harmless just by knowing that (1) the average lean human has fat reserves to last three months, (2) total fasters don't go through some calamity like losing lots of muscle protein (if they did, there'd be unambiguous results everyone knew) and (3) in the EEA it was probably common to have periods of scarcity such that you go several days without finding food. In other words, fasting was about as unusual as, you know, cloudy weather. These observations are already strong enough evidence to me that I consider this topic "done" -- I will be surprised if a RCT shows it to be harmful, and I'll need a deep meditation on where I went so wrong.

With sleep, it's not so clear, because... unsourced claim here, but The Primal Blueprint among other popular books have claimed that an average "working day" in the EEA was less than ~2 hours, or at any rate shorter than a modern working day. That's a lot of free time for sleep!

That ~2 hour figure can certainly be unpacked: does idle foraging while on a walk with your friends count as "work"? But neither sleep nor work-time seem like resources to be conserved in the same unambiguous way as calories. Sleep or no, bodies need downtime after extended exertion, and they may as well take a nap then. Wakefulness or no, there may be nothing useful to do at certain hours of the day, so we may as well sleep extra. So the amount we slept may have been quite open to modulation by external influences.

This can still back up the idea that you can subtract a few hours off your sleep need with the right stimulus -- I just think that an analogy with fasting is a type error. In particular, the sub-analogy that feeling sleepy would signal something good.

Another problem with the analogy. People who fast regularly will tell you that they usually don't feel hungry. So if you like the analogy, you also shouldn't usually feel sleepy.

Replies from: Notestream
comment by Notestream · 2022-02-14T12:54:21.879Z · LW(p) · GW(p)

We may be "anthropomorphizing" hunter-gatherers when trying to place anything they do into our category of "work," hence the wide variability of opinions as to how much work they really do. They are either engaged in activity conducive to survival (including things like playing, socializing, dancing, and exploring) or they aren't. Foraging while exchanging information with friends is certainly beneficial for hunter-gatherers. I agree that, through my own lens, this activity appears fairly idle, but that's because my cultural ideal of work is fast, energetic and high output. But if you're foraging, it's more efficient to move slowly so that your brain has time to recognize all the edibles you pass by. And listening and talking doesn't seem to interfere too much with visual processing (or else there would be a lot more car accidents), so why not kill two birds with one stone?

comment by FinalFormal2 · 2022-02-22T18:09:14.794Z · LW(p) · GW(p)

I am two people removed away from a gentleman who has a sleep disorder that means he can never sleep more than two hours, and he's otherwise healthy. That seems to suggest if there are negative effects from lack of sleep, they aren't incurred from practical biological necessity, but from what our brains do to enforce sleep.

Also, OP, if you actually don't have any ill effects from 6 or so hours of sleep, it's possible you might have a similar genetic condition.

In the comments, I don't understand why people seem to be so swayed by the comparison of sleep deprivation to fasting or exercise. The only thing that tells you is that things that might seem harmful sometimes aren't, which is obviously the case. It doesn't speak at all to whether or not acute sleep deprivation is good for you no more than it speaks to whether not getting occasionally getting blitzed is good for you.

Similarly, the idea of 'variety is good' as a general principle of health has so many obvious exceptions, and seems to be just be based on memes about nutrition. It doesn't seem like a principle you could use to make accurate predictions about health science.

Replies from: frankybegs
comment by frankybegs · 2022-02-27T22:04:11.170Z · LW(p) · GW(p)

In the comments, I don't understand why people seem to be so swayed by the comparison of sleep deprivation to fasting or exercise. The only thing that tells you is that things that might seem harmful sometimes aren't, which is obviously the case. It doesn't speak at all to whether or not acute sleep deprivation is good for you no more than it speaks to whether not getting occasionally getting blitzed is good for you.

Which comments are you referring to?

And I thought it was clear enough that those analogies were meant to demonstrate that there's no necessary connection between something feeling bad in the short term and being bad for you. There was no claim that things that feel bad in the short term are, therefore, good for you. As you point out, that would not follow. But the author never attempts to make that argument.

Replies from: FinalFormal2
comment by FinalFormal2 · 2022-02-28T16:14:38.568Z · LW(p) · GW(p)

Elizabeth's comment and one other that I remember but can't find now.

Revisiting this, I dislike the analogy even more. Analogies aren't how you do science, and I'd argue that a majority of the time, things that feel bad are bad. Exercise doesn't even actually generally feel bad, it generally feels good. You don't have to encourage children to run or skip or hop, you only have to do that with sedentary adults.

Also, the author says that the state of sleep research is "100% a psyop," so I'm very sceptical of their thinking in general.

Maybe they do have legitimate points, and good ideas can come from people who think differently than the majority, but this article is full of red flags. Somebody else can sort this.

comment by Mark_ · 2022-02-22T07:48:18.110Z · LW(p) · GW(p)

I’m pretty sure that the entire “not sleeping ‘enough’ makes you stupid” is a 100% psyop

Why would it be a psyop? By who and with what motivation/intention?

Replies from: frankybegs
comment by frankybegs · 2022-02-27T22:05:37.992Z · LW(p) · GW(p)

I think we can safely infer that that was not to be taken as a serious claim.

But by his own logic, it doesn't belong in a post that offers itself for citation!

comment by romeostevensit · 2022-02-13T00:04:55.845Z · LW(p) · GW(p)

I started walking in the morning (within an hour of waking, though supposedly within thirty minutes is even better, don't know evidential base) and found myself sleeping less and waking earlier more consistently and feeling tired around the same time more consistently. From ~averaging 8.5 down to 7.5. Sometimes I wake really early, around sunrise, and find myself wanting a nap in early evening. This was very notable for me after decades of sleep problems and hating hating hating sleep interventions.

comment by mingyuan · 2022-02-12T05:34:20.627Z · LW(p) · GW(p)

This is super interesting, thanks! I'm almost embarrassed that it never occurred to me to question some of these things. Like Elizabeth, I'm not totally sold on all the conclusions right now, but it's still interesting to think about.

Personal reflection / anecdotal evidence: There are two time periods (~9-12 months each) that I look back on as my happiest and most productive times. During both, I stuck to a strict 10pm–6am sleep schedule, and I felt great (I did sometimes nap if I felt I needed it, I think). However, when not on a strict schedule, I usually sleep between 8.5 and 10.5 hours. I thought that the fact that this is how long I sleep when not woken and not on a schedule meant it's how long I 'need' to sleep, and my behavior has been reinforced/exacerbated by my husband also having high 'sleep need'.

Having read this, I'm more motivated than ever to try to get back on that strict 8-hour-per-night schedule. I just need actual buy-in from the person who shares my room, which is always the bottleneck, alas.

 

Also, I have an aunt who has slept 5-6 hours per night for her entire life. She's not the healthiest person I know but she has at least lived past the age of 60, and she's super productive.

comment by Edward Kmett (edward-kmett) · 2022-03-22T12:22:58.791Z · LW(p) · GW(p)

I heavily sympathize with a lot of the views from this post. 

I used to sleep much more (~9 hours), but as I've aged, I now tend to sleep between 3-5 hours a night. This was a rather conscious choice on my part, but now I find it hard to revert to my previous behavior. I switched to various forms of polyphasic sleep during my bender through academia from 2004-2006, and while I eventually abandoned polyphasic, I haven't switched gone back to a "regular" sleep schedule since.

I do find that at my most acute stage of sleep deprivation I become much more mono-focused. I have to stay interested to stay awake, so I dive into everything my ADHD wants me to focus on to stay locked in. As long as I can ride this mode of operation, I can stay awake truly ridiculous numbers of hours without dipping into modafinil/adrafinil or other anti-sleep agents.

At the risk of dipping into anecdote territory, my biggest concern with having "lived this" for the last decade or two is the apparent sharp impact on cortisol levels. 

I gained a ton of productivity for the first decade or so of this practice, but then failed to adequately manage my weight. Now I have a number of health issues that correspond to chronic inflammation.

I still consider on net to have made a gain with the use of 'front-loading' my conscious time on earth, but I do feel the need to consider these longer term impacts on cortisol and core body fat. Recently I've been trying to find the right middle ground to give my body enough time to recover from exercise and still retain high-focus. e.g. using semaglutide off-label to bring weight under control.

If I had it to do over again, I would probably try to be a lot more careful about monitoring such things BEFORE I reached the point of having to do more drastic steps to bring things back into line.

comment by velcro · 2022-02-22T12:39:04.710Z · LW(p) · GW(p)

Generally interesting, but I have a quibble with this:

In the text here, you say

>>Walker outright fakes data to support his “sleep epidemic” argument. The data on sleep duration Walker presents on the graph below simply does not exist:

I went to your link to see the proof that it does not exist.  Pretty extraordinary claim.  Difficult to prove a negative and all.  Figured I would find something solid.  Other than two studies with evidence that contradicts Walker's general claim with a few specific examples, here's what you had:

>>I have not been able to find any data that would support the sleep duration numbers Walker provides in the book and it appears that they were simply made up.

I think that speaks for itself.

Replies from: AllAmericanBreakfast, guzey
comment by DirectedEvolution (AllAmericanBreakfast) · 2022-02-23T18:07:50.774Z · LW(p) · GW(p)

You can check this out for yourself. Search PubMed or Google Scholar for "sleep deprivation cancer risk." Plenty of studies come up, but the vast majority find little-no link. The biggest hazard ratio I could find was 1.6, which is not a doubled cancer risk. Note also that Walker has actually retracted his "WHO has declared a sleep epidemic claim," so we have a concrete example of the guy making stuff up.

comment by guzey · 2022-02-22T20:13:10.831Z · LW(p) · GW(p)

Yep

  1. He didn't have a source in the book.
  2. Multiple people asked him for a source and he never provided one
  3. The dad is INCREDIBLY divergent from all other data we have. Literally all other data people sleep around 7 hours maybe more maybe less while his data shows almost 9 hours of sleep on average.

Given these three, and the fact that he did literally alter a graph in one other place in the book, I'm pretty sure he just faked this data. If you manage to find the source, I'll edit the posts and will apologize to Walker.

comment by tb_throwaway · 2022-02-14T21:23:34.955Z · LW(p) · GW(p)

There's a lot of interesting stuff in the post, but the following counter-point you offer to "the idea that sleep’s purpose is metabolite clearance" I can't quite follow:

The paper is called “Sleep Drives Metabolite Clearance from the Adult Brain”. The abstract says:

The conservation of sleep across all animal species suggests that sleep serves a vital function. We here report that sleep has a critical function in ensuring metabolic homeostasis. Using real-time assessments of tetramethylammonium diffusion and two-photon imaging in live mice, we show that natural sleep or anesthesia are associated with a 60% increase in the interstitial space, resulting in a striking increase in convective exchange of cerebrospinal fluid with interstitial fluid. In turn, convective fluxes of interstitial fluid increased the rate of β-amyloid clearance during sleep. Thus, the restorative function of sleep may be a consequence of the enhanced removal of potentially neurotoxic waste products that accumulate in the awake central nervous system.

At the same time, the paper found that anesthesia without sleep results in the same clearance (paper: “Aβ clearance did not differ between sleeping and anesthetized mice”), meaning that clearance is not caused by sleep per se, but instead only co-occurrs with it. Authors did not mention this in the abstract and mistitled the paper, thus misleading the readers. As far as I can tell, literally nobody pointed this out previously.

I'm not quite following the meaning that clearance is not caused by sleep per se, but instead only co-occurrs with it bit. So yes, sleep allegedly results in X (clearance), that you can also get through, e.g., anesthesia. I don't see how this is more misleading than a statement like exercise results in autophagy which you can also get by using exercise mimetics hypothetically would be (if/when we had enough data on exercise mimetics, for ex.). Basically, you can get to a good thing (clearance/autophagy) in both of these cases through various means. Why would this be a misleading thing to say about sleep/exercise?

 

Is the idea that we should be seeking to anesthetize ourselves (without sleep) to get these specific benefits at least, instead of committing to more sleep (which would be an overkill in this presentation)?

 

Not responding to the broader reaction to this paper in your post btw, just this one bit. Thanks

 

EDIT: I also want to note that you don't seem to address the role of sleep in immune function/lowering systemic inflammation markers beyond Walker's failures of citations. There's a bunch of literature on this on pubmed etc., which tbf I haven't reviewed in detail so perhaps it's all bunk! But it would've been good to have insight into that, as my impression ATM is that sleep certainly strengthens your immune system and lowers systemic inflammation.

Replies from: AllAmericanBreakfast
comment by DirectedEvolution (AllAmericanBreakfast) · 2022-02-23T18:00:23.186Z · LW(p) · GW(p)

Sleep Disturbance, Sleep Duration, and Inflammation: A Systematic Review and Meta-Analysis of Cohort Studies and Experimental Sleep Deprivation (schi-hub link).

Here's the #1 link on Google Scholar that comes up on a search for "inflammation sleep deprivation" (> 800 citations).

They're looking at inflammatory cytokine levels (CRP, IL-6, and TNF-a), which I can confirm (biomedical engineering MS student currently studying immunology) are key drivers of the inflammatory response, though the immune system is a complex interconnected pathway without a straightforward protein "gas pedal." Here's my quick interpretation of the abstract in terms of the support it lends for the sleep deprivation/inflammation connection.

Pros:

  • n > 50,000, no evidence of publication bias
  • Found sleep disturbance (poor sleep, sleep complaints) associated with CRP and IL-6, and shorter sleep duration (< 7 hours/night) with CRP.
  • The researchers do note in the last sentence findings from another study that "Indeed, treatment of insomnia has been found to reduce inflammation and together with diet and physical activity represents a third component in the promotion of sleep health." The insomnia treatments in the linked study were CBT and tai chi. 

Cons:

  • Neither experimental sleep deprivation nor sleep restriction was associated with CRP, IL-6, or TNFα.
  • Nothing at all was associated with TNF-a (which the researchers chalk up to "low statistical power" with n = 672, as opposed to the n=34,000 for CRP and n=3,000 for IL-6).
  • The biggest effects were for people with sleep disturbance and complaints, but one interpretation is that this is due to an underlying autoreactive or pathogenic immune response that causes poor sleep.

My takeaway from this study is that it actually lends strong support to the idea that inflammation is not driven by sleep deprivation. The right interpretation seems to be that if you're having sleep disturbances, then your doctor may want to check for an inflammatory cause.

However, the authors themselves say in the discussion that "sleep disturbance is associated with inflammatory disease risk and all-cause mortality, possibly by effects of sleep disturbance on inflammatory mechanisms."

The authors think that sleep deprivation enhances TLR-4-stimulated production of IL-6 and TNF-a. The immune pathway starting with TLR-4 is well-established, and you can find it covered in a good textbook like Janeway.

The key component of these authors' argument, though, is linking sleep deprivation to that pathway. As evidence, they cite a 2006 study (n=30) that assessed IL-6 and TNF-a production with an experimental manipulation comparing levels after 8 hours of sleep vs. 4 hours of sleep. Then they took blood assays at 8 AM, 12 PM, 4 PM, 8 PM, and 11 PM. This study has a lot of problems:

  1. "Data were analyzed using SAS statistical software (version 9.13; SAS Inc, Cary, NC). Missing values were handled using cell-wise deletion." Missing data is a common problem in research, but there are sound statistical methods for dealing with it. Deleting the missing values is not one of them. And how the heck are these researchers missing data when they're collecting it themselves?
  2. "Compared with baseline levels, the percentage of monocytes expressing IL-6 and TNF-α was significantly increased at 8 AM after PSD (t107 = −2.3; P<.05); this increase normalized at subsequent time points." So they found an increased percentage of monocytes expressing IL-6 and TNF-a at 8 AM, but not at 12 PM, 4 PM, 8 PM, or 11 PM. No mention of multiple comparison corrections in their analysis, but let's hope they did it and didn't tell us about it. Also, unlike their nonsignificant P-values, which are given precisely, they merely say "P < .05." So then they went on to the exploratory analysis.
  3. "The number of monocytes was not different at the 8 AM time point after PSD (t1,29 = −0.3; P>.85)."
  4. Finding elevated monocyte cytokine expression at 8 AM, they also looked at transcription in these monocytes at only this timepoint, and found that indeed, mRNA is at 6-fold (IL-6) and 2-fold (TNF-a) levels.
  5. All participants had their sleep deprivation on day 4, after 3 days sleeping in a lab having their blood drawn 5 times a day.

Let's just say that this is not strong evidence of sleep deprivation-driven inflammation. But it is probably some evidence. This paper (but not the original metastudy) also links to 5 other papers buttressing its claim of a sleep deprivation-inflammation causal link.

I'm not going to go this in-depth into all of them, but let's at least get the takeaways:

  1. Elevated lymphocyte levels found both after sleep deprivation and in the afternoon and evening of the day following sleep. I have to admit I find the abstract confusing: they say that a decrease in monocytes, NK cells, and lymphocytes may "serve to support ongoing immune defense." That's the opposite of how I'd interpret a low level of white blood cells. But maybe I'm missing something. 
  2. Sleep deprivation reduces NK and cellular immune responses in humans. The title says it all.
  3. The study finds impairment in vigilance after sleep deprivation to 6 hours of sleep/night, increases in IL-6 secretion and, in men but not women, TNF-a, as well as decreases in cortisol.
  4. "Relative to the partial sleep deprivation condition, subjects in the total sleep deprivation condition had elevated plasma levels of sTNF-αRI on day 2 (P = .04), day 3 (P = .01), and across days 2 to 4 of sleep loss (P = .01) and elevated levels of IL-6 on day 4 (P = .04)."
  5. "The CRP concentrations increased during both total (88 hours awake) and partial (4.2 hours of sleep) sleep deprivation conditions, but remained stable in the control condition."

Note that in these studies, the researchers are commonly taking frequent blood samples. For example, in that last study, they took hourly blood samples. They're being continuously monitored, catheterized, in a lab environment, sleeping with a catheter, and getting their rectal body temperature taken. Again, I think we have to worry about the potential confounding impact of stress, blood loss, etc on driving this immune response.

Looking at the results from these 5 studies, we see a mix of effects. In sleep deprivation, sometimes inflammatory cytokines are up, but other times, inflammatory cells are down. Results are there but inconsistent.

Moreover, and crucially, these are short-term studies that don't investigate the health impacts we'd actually care about from inflammation. That's not their fault - they're a valuable contrbution to scientific knowledge - but we can only learn so much from studies like this. I am not ready to accept with any great confidence a claim that "sleep deprivation shreds your immune system" based on this data.

comment by Gunnar_Zarncke · 2022-02-22T20:47:24.079Z · LW(p) · GW(p)

One of the things that I am really worried about is Alzheimer's. Even a slight risk of Alzheimer's would be enough to convince me to sleep more. Alzheimer's is significantly caused by UPDATE: correlated with the buildup of plaques in the brain, and the process of cleaning that away seems to be tied to sleep or at least the circadian rhythm - which I guess can be disrupted in many ways. 

Recent study:
https://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1009994 

Replies from: ChristianKl, guzey
comment by ChristianKl · 2022-02-22T21:19:23.257Z · LW(p) · GW(p)

Alzheimer's is significantly caused by the buildup of plaques in the brain

Alzheimer's is correlated with a buildup of plaques in the brain, but there's no evidence that it's caused by that.

The FDA did approve Aduhelm based on that thesis, but that decision is widely ridiculed and got multiple people from their scientific advisory panel to step down. 

Replies from: Gunnar_Zarncke
comment by Gunnar_Zarncke · 2022-02-22T22:44:25.000Z · LW(p) · GW(p)

Fair. Still, I wouldn't want to mess with whatever causes either.

comment by guzey · 2022-02-22T20:50:44.912Z · LW(p) · GW(p)

Have you done an explicit calculation of your perceived increased risk in Alzheimer's and compared it to QALY (potentially) gained by decreasing amount of sleep?

Replies from: Gunnar_Zarncke
comment by Gunnar_Zarncke · 2022-02-22T21:15:30.787Z · LW(p) · GW(p)

I'm sleeping less than many people, and I usually feel powerful enough at 6.5h per day (including actually falling asleep). Though it is a fragile balance that can be tipped to headache easily, and then it isn't net-positive anymore. But again, I'm most worried about my brain not getting enough time to cleanup stuff and this over time adding up without me noticing and then losing a lot of QUALYs later. So I want to be sure to be sufficiently far away from the point where stuff builds up.

comment by angmoh · 2022-02-13T14:01:32.067Z · LW(p) · GW(p)

I can anecdotally report that when I started consistently getting up immediately upon my alarm going off the subjective feeling of the first 5-10 minutes was far superior and I didn't feel much tiredness even with a relatively short night of sleep. I started doing this through setting my alarm to the maximum latest time possible and still allow me to get to work on time, and then noticed how much better I felt while doing this (previously I was a chronic snooze-button masher and felt pretty groggy waking up).

I have noticed in the WFH/office phases of the past 2 years the effect has persisted - a worse subjective waking up experience when WFH. I think it's because without the pressure of needing to be at work, I don't develop an automatic routine of simply getting up unthinkingly when my alarm goes off.

I think part of this is related to how good your internal biological clock is. I'm the type of person that will wake up pretty consistently a few minutes before an alarm goes off anyway (sometimes even when the alarm is not my usual time, such as for a flight). Maybe the 'get up immediately' approach wouldn't work as well if this isn't you.

comment by Cédric · 2022-02-13T11:13:35.493Z · LW(p) · GW(p)

Unlike the other commentors, I am sold enough on the conclusion to give it a try.

I've been waking up at the same time every day (~95% of the time) and sleeping at roughly the same time every night (~70% of the time). What I'll do is keep waking up at the same time but just go to bed when I'm tired instead of ~8 hours before my waking time.

I don't have any issues with tiredness/low-energy. Ideally that would continue and I would be able to reclaim an hour or two from each day.

Replies from: Cédric
comment by Cédric · 2022-06-09T04:49:41.645Z · LW(p) · GW(p)

Follow up:

I didn't try the experiment for very long but here are my observations when sleeping fewer hours:

  • Lower self-control (more Uber Eats, more checking socials during work)
  • When I was able to exert enough control to concentrate on something, my concentration was deeper
  • Felt more tense/stressed? I guess it must be due to more adrenaline and cortisol
  • More creative (increased frequency of random ideas while doing chores/mundane tasks, more lost in interesting thoughts - when a thought was particularly interesting, I'd deeply and automatically follow the thoughts for multiple minutes)

So basically I felt tired, energetic, more disinhibited, creative, unable to stay concentrated but when concentrated, the concentration was deeper. It was a very oxymoronic experience with the tired + energised and contradictory effects on concentration.

Overall, pros and cons but if I can overcome the self-control problem it will be a net positive productivity wise. However, due to the stress that's another point deducted from the healthiness of sleeping fewer hours (not to mention the other non stress related potential issues).

The main thing that this has unlocked for me is that it has freed me from the fear of missing out on sleep. I sleep my 8 hours but don't sweat it if I don't sleep well or if I stay up late.

I also think it's a good idea to try random things, even if they fly in the face of conventional wisdom. Obvious caveat is you might cause irreparable damage to yourself but as long as you're careful not to take self-experimentation too far there might be some benefit to walking off the beaten track.

comment by Cédric · 2022-02-13T11:08:13.572Z · LW(p) · GW(p)

I used to use a Fitbit to track my sleep. I noticed that after sleeping very few hours, I'd have more % deep and REM sleep the following night (and less % light sleep / restlessness) often enough for me to notice a correlation. I checked my friend's Garmin sleep stats and it's roughly the same.

I wouldn't give too much weight to the accuracy of this observation (confounding, device accuracy etc). However it just about makes the cut to share it in a comment imo.

comment by mikbp · 2022-03-08T15:31:47.370Z · LW(p) · GW(p)

One point that I would like to see discussed is the relation between lack of sleep and allergies. In general, I have some minor dust allergy. However, when I'm sleep deprived and something triggers my allergy, the symptoms (sneezing, nose running, red eyes...) are several orders of magnitude stronger and really impede normal life. The effect is cumulative, I mean that this happens only when I haven't slept enough for several days. I take it as something valuable, as it is a reliable sign for me that I need to rest.

I have once quickly searched a bit the scientific literature for this effect and seemed scarce. Some research mentioned it, but it really seemed something very under-studied.

 

Beyond this comment, my personal experience with productivity vs. sleep is that when I don't sleep enough, I am really much less productive. The periods when I have slept the fewest, I have gotten up at very consistent times, so this does really not seem the cause. When I'm sleep deprived, I don't have problems doing physical stuff but I'm much less able to concentrate, so the effect depends a lot on the nature of the work. Probably I also don't have any major issue doing fun stuff even if it needs concentration. Sadly we mostly cannot only do fun stuff... But, for example, in the Uni I started to get much better grades when I decided to never sign up for lectures starting before 10h, because I was (partly for external factors, partly for lack of will power) unable to go to sleep early enough to get enough sleep time otherwise.

comment by mikbp · 2022-03-08T14:59:24.796Z · LW(p) · GW(p)

I'd be interested on your thoughts on baby blues. That women tend to get depressed in the most sleep-deprived time of their lives does seem very contradictory with what you expose. (I know, hormones; but still, strange timing). I guess one could argue that without the effects mentioned in the post, it would be all the women that would suffer baby blues. Is there any research on this?

comment by FinalFormal2 · 2022-02-22T18:27:44.508Z · LW(p) · GW(p)

I'm very interested in the idea that most of the negative recorded effects of sleep deprivation are caused by sleepiness, not sleeplessness. However, there are some effects that you cannot attribute to sleepiness, like hormonal changes

I would love to see more research done, but I think I've decided epistemically that I have to trust the body of knowledge before I trust somebody on the internet. It seems like you're alleging an entire conspiracy in sleep science, and your evidence is not good enough to brook that.

In addition, using evidence like a sleep scientist falsifying data once to write a book does not actually help your case. Like a lot of your evidence, it's n=1, and it adds to the perception that you're alleging a conspiracy that really has no motive to exist. 

Your example of a sleep deprivation expert one time saying that 5.5 hours can be alright is another n=1 case and it's frustrating to read because you seem like someone who's very passionate about this topic, but you need to write better and discriminate among evidence so that you lead with your best data.

Edit: Reversed stupidity is not brilliance. Saying that the state of sleep of sleep research is poor does not support making wild claims similarly supported by poor research.

Replies from: AllAmericanBreakfast, ChristianKl, JonasMoss
comment by DirectedEvolution (AllAmericanBreakfast) · 2022-02-23T16:48:14.663Z · LW(p) · GW(p)

One of Guzey's projects is to advance his own claims about how sleep works, and I agree that his data is on the bottom of the epistemic pyramid. His other project, though, is a critique of the interpretation of sleep research data, and here he is on firmer ground.

You can check out my comment [LW · GW] above showing that investigating a meta-study of sleep research on the type of sleep deprivation Guzey's mainly focused on (i.e. a consistent 5.5 hours or of sleep so per night) shows that the meta-study is profoundly flawed. You can check it out for yourself - that's how science is supposed to work!

In addition, using evidence like a sleep scientist falsifying data once to write a book does not actually help your case.

I think you should split up your assertions about Guzey's speculations about how sleep works, his criticism of sleep studies, and his assertions about the state of the field.

Let's say that the field really was in a poor state, with a heavy admixture of poor studies, misleading analysis, and various intensities of misrepresentation up to and including outright fraud. We've seen this phenomenon in other scientific fields. Our priors ought to be low, perhaps, but it's not impossible by any means.

If we wanted to find out if this was true, how would we go about it? Starting with an epistemic spot-check of a widely praised popular book by a leading sleep researcher makes sense.

Discovering the problems Guzey found, such as trimmed graphs, uncited claims not representative of the findings of any real study, false claims about health declarations by the WHO, and an uncritical uptake by mass media, are exactly the sort of things that might naturally motivate somebody to speak up and keep researching. If this finding "doesn't help his case," then what could?

Guzey's not alleging a conspiracy ("a secret plan by a group to do something unlawful or harmful").

Edit: Actually, he did say "’m pretty sure that the entire “not sleeping ‘enough’ makes you stupid” is a 100% psyop." It's not clear who exactly is making this claim (sleep researchers are far more specific and formal, even if their claims are problematic in other ways), so this both has shades of a conspiracy accusation and a weakman/strawman. =

He's alleging a history of bad behavior that results from bad incentives and selection effects:

So why has sleep research not been facing a severe replication crisis, similar to psychology?

First, compared to psychology, where you just have people fill out questionnaires, sleep research is slow, relatively expensive, and requires specialized equipment (e.g. EEG, actigraphs). So skeptical outsiders go for easier targets (like social psychology) while the insiders keep doing the same shoddy experiments because they need to keep their careers going somehow.

Second, imagine if sleep researchers had conclusively shown that sleep is not important for memory, health, etc. – would they get any funding? No. Their jobs are literally predicated on convincing the NIH and other grantmakers that sleep is important. As Patrick McKenzie notes, “If you want a problem solved make it someone’s project. If you want it managed make it someone’s job.”

you need to write better and discriminate among evidence so that you lead with your best data.

This I agree with. As I noted in another comment, Guzey's a lot of things right here, except that the tone and format of his post makes his argument feel hard to respect. It comes across as ranty, manic, highly motivated ("passionate"), the sort of style we now associate with Qanon. But this is LessWrong, and I think that here, at least, we should try to focus on substance over style.

Replies from: guzey
comment by guzey · 2022-02-23T22:45:02.883Z · LW(p) · GW(p)

This I agree with. As I noted in another comment, Guzey's a lot of things right here, except that the tone and format of his post makes his argument feel hard to respect. It comes across as ranty, manic, highly motivated ("passionate"), the sort of style we now associate with Qanon. But this is LessWrong, and I think that here, at least, we should try to focus on substance over style.

Tbh I'm very confused about the issues you have with my tone. I very deliberately called the post "Theses" on sleep! And I believe I very explicitly wrote that these are my conclusions from my reading of the literature and in no way am trying to make people think that the analogies that I thought of that I find convincing should be convincing to other people. I simply put forward some theses with extremely variable level of evidence between them but for each of these it is the case that I personally am convinced that they are actually true.

Replies from: AllAmericanBreakfast, frankybegs, ChristianKl
comment by DirectedEvolution (AllAmericanBreakfast) · 2022-02-24T00:51:37.559Z · LW(p) · GW(p)

in no way am trying to make people think that the analogies that I thought of that I find convincing should be convincing to other people.

This reads as a denial of persuasive intent, which is clearly not the case.

Your post consists of more than analogies that you thought of. It also consists of data, your own self-experiments, arguments, citations, critiques of the literature and of Matthew Walker's book. It doesn't need to make us convinced of the truth of all your beliefs re: sleep to be a piece of writing with persuasive goals. I posit that virtually anybody who reads either this or your original piece on Walker's book would find them clear examples of scientific writing that's aiming to persuade the reader.

I happen to find your work pretty interesting, something I've already spent a lot of time investigating here in the comment section. It's the kind of information I'd want to share and explore with other people. As you were the one who brought it to my attention, I'd like to be able to use you and your writing as a reference when I do so.

However, I have to consider what the reaction of the person I shared it with might be if I did so.

Knowing the typical reactions of people who are interested in this topic but who aren't diehard LessWrongers, I anticipate (for reasons that are hard to make clear) that they would be turned off by stylistic features of your writing before they opened their minds enough to consider the substance of your theses in any meaningful way. Moreover, they would likely view me as foolish for reading something with those stylistic features, because there is a linguistic stereotype that those features map onto a certain type of particularly low-status person: an internet conspiracy theorist.

It's not particularly fair or right that this stereotype exists. Consider that at one time, and to some extent still today, the accents of certain ethnic groups were/are taken as a negative indicator of intelligence. While this stereotype is harmful, it also exists, and members of these groups sometimes choose to speak in an accent deemed "higher-class" in order to elicit certain desirable reactions from groups with a tendency to stereotype. One of the terms here is "code-switching." An example is an American Black person switching from Ebonics to white-sounding English in the classroom, and speaking Ebonics at home or with their friends.

Some of the stylistic features that I fear would be taken as sounding like a conspiracy theorist include:

  • Run-on sentences
  • Use of terms like "psyop" and Scientific Consensus (TM)
  • Inclusions of Twitter threads, particularly by scientific nonentities
  • Lots of switching between bold, italics, all-caps.
  • The direct address ("Even if I convinced you about the “sleeping too much” part, you are still probably wondering: but what does depression have to do with anything? Isn’t sleeping a lot good for mental health? Well…")
  • Including speculations from other authors without any context for who they are, or why we'd particularly care about their speculation. Example: the Jeremy Hadfield quote.
  • Including irrelevant details like Nassim Taleb quote-tweeting you. If a reader didn't know who you are, or who Taleb is, this could potentially come off as somewhere between confusing and narcissistic.
  • Leading a section with the assertion that "the vast majority of it being small-n, not pre-registered, p-hacked experiments," followed not by a methodical attempt to prove the point but by further assertions about the bad motives of the researchers. [Group] is doing [bad thing] and because of [bad motives] is a basic pattern of conspiracy-theory discourse; I'm sure you can fill in the blanks yourself with examples. It's not that no group has ever done a bad thing for bad motives, but that if you're going to make that claim, you really need to back it up. You've done that with Matthew Walker, but not with his colleagues, and these are human beings we're talking about. They deserve individual consideration on their merits and substantial evidence of wrongdoing before they're on the receiving end of a callout, even on a blog. This is especially important because you literally accuse them of the moral equivalent of murdering tends of thousands of people.
  • Implicitly insulting the reader if they disagree with you ("Why is everyone in love with charlatans")

Not all of these are individually inappropriate, but in the aggregate, they convey a strong impression that it'll look bad to publicly take you seriously. They also make it seem like, even if you are correct on some or all of these theses about the incorrectness of current sleep research or the correctness of your own speculations, that you are operating with a disturbing attitude on how to navigate the politics. A person with a bright idea who'd be a terrible ally.

My strongest objection to your writing style is the accusation that sleep researchers in general are doing shoddy research and culpable for the equivalent of killing people. This is the point at which I would have stopped reading your article (and lowered my likelihood of reading other things you write in the future), if it weren't for the fact that Elizabeth was the one who curated the piece.

The other points I raise here are annoying, but I could wade through them. The problem is that, as I say, they make it hard to consider sharing this piece with others, because of they way I expect the stereotype they invoke would reflect on me. If you would like to continue driving conversation on this important topic - and I think you're onto something here and should continue - I strongly recommend that you eliminate the unsupported and hystrionic accusations, particularly the murder-like accusations and accusations against groups. I also recommend that you ask your editors to help you eliminate stylings that smack of the conspiracy theorist, since your comment makes me think that this is just not something you have a sensitivity to. That's no sin, but it is a problem for your readability.

Replies from: guzey
comment by guzey · 2022-02-24T01:27:34.941Z · LW(p) · GW(p)

re: persuasive intent -- yes, of course I want to persuade people but I'm believe I'm being very clear about the fact that some sections are just analogies.

My strongest objection to your writing style is the accusation that sleep researchers in general are doing shoddy research and culpable for the equivalent of killing people. This is the point at which I would have stopped reading your article (and lowered my likelihood of reading other things you write in the future), if it weren't for the fact that Elizabeth was the one who curated the piece.

I believe this is a very strong misreading of what I wrote. I did write that sleep researchers in general are doing shoddy research (I'm pretty sure this is true). I never wrote that they are culpable for the equivalent of killing people.

Here's the paragraph this is referring to, I believe:

Why are people not all over this? Why is everyone in love with charlatans who say that sleeping 5 hours a night will double your risk of cancer, make you pre-diabetic, and cause Alzheimer’s, despite studies showing that people who sleep 5 hours have the same, if not lower, mortality than those who sleep 8 hours? Convincing a million 20-year-olds to sleep an unnecessary hour a day is equivalent, in terms of their hours of wakefulness, to killing 62,500 of them.

I thought specifically about how to phrase the last sentence in order for it to be only about facts rather than accusing anyone and the "convincing a million 20-years-olds" appears clearly to be just a thought experiment to me.

Replies from: AllAmericanBreakfast, Mo Nastri, tslarm
comment by DirectedEvolution (AllAmericanBreakfast) · 2022-02-24T06:25:41.637Z · LW(p) · GW(p)

appears clearly to be just a thought experiment to me.

The point isn't what you intended to come across in your writing, but what actually does come across in your writing, and the expectations that creates in the reader about how others will perceive your writing.

By analogy, let's say you go to a party and tell a joke making fun of my friend Sarah's shoes. You think it's funny and mean it as a bit of friendly teasing. I know that you're a little nervous and are just trying to connect, and the joke honestly seems kind of funny to me.

However, I also know Sarah's sensitive about her shoes, and that the others who heard the joke probably hear it as mean-spirited, because they don't know you very well. Plus, the joke really did feel mean to me, even though I also found it humorous at the same time.

Because of that, I feel pressure to reprimand you, and maybe not to bring you back to another party in the future. This is partly because I want to make Sarah feel defended, but also because I'm concerned that others will think I'm mean if I don't distance myself from you. They'll certainly think that if I then go around telling other people the joke.

It's this sort of reaction that the aspects of your writing I pointed out are provoking. And yes, in a real-life party situation, you could apologize and make amends, and things would probably be OK. However, on the internet, in a piece of writing, you don't have that opportunity. It has to come off right the first time, without "help" from the comments, except in dialog with the very small number of highly-engaged LessWrongers here.

Because of the effort you've put into writing this up and seeking attention for your ideas, and also because I find your ideas intriguing, I'd prefer if you produced writing that avoided the perception problem I'm describing here. That way, I could more easily share this information and build on it over time. Right now, it's a real barrier.

Incidentally, your math is wrong.

Life expectancy in the USA at age 20 is about 62 years.

24 hours/day * 365 days/year * 62 years (life expectancy at age 20) = 543,120 hours ~= 500,000 hours

If sleep scientists are convincing 1 million 20-year-olds to waste an extra hour on unnecessary and unwanted sleep every day, that could be interpreted as 2 "lives" per day.

62,500 lives / (365 days/year * 2 lives/day) = 62,500 lives / (730 lives/year) = 85.6 years.

It would take 85.6 years for sleep scientists to "waste" that much of this cohort of 1 million 20 year old's time, all other assumptions granted. And I think you should probably address the fact that there are many more than 1 million people, while sleep scientists probably share far less than full responsibility for the sleep choices of the average person. Also, the difference between an extra hour of sleep and an extra hour of death is probably, to most people, vast.

Let's say you take this criticism into account and wanted to word the sentence I found offensive. You might say something like:

Based on [calculation with appropriate caveats and qualifications], I estimate that the US adult population of 209 million people gets about 1 unnecessary hour of sleep per day. This amounts to about 24,000 person-years every day, or around 400 lifetimes. It adds up to almost 150,000 lifetimes every year, just in the USA. If that extra hour is "junk sleep," as I contend, we are missing out on a huge amount of happiness in the pursuit of our pillows!

It's not your style, and it's a lot longer and less punchy. But it still conveys the scope of the issue, while framing it as a goal to be (perhaps) attained rather than an occasion for blame.

I leave it to you to figure out how to make use of this information.

Replies from: TomNorth
comment by TomNorth · 2022-05-10T11:51:35.270Z · LW(p) · GW(p)

This is along similar lines to criticism I sent to guzey before publication, albeit many times more eloquent. My criticism was dismissed similarly. The offhand dismissal of considered criticism also sounds like the discourse of people whose ideas I'm wary of. This in turn makes me wary of guzey's ideas, which I am otherwise sympathetic towards.

comment by Mo Putera (Mo Nastri) · 2022-02-28T16:50:43.830Z · LW(p) · GW(p)

I'm confused about your pushback to AllAmericanBreakfast's (great) feedback on your style, which I find antagonistic to the point that (like AAB) I'm not comfortable sharing it with anyone, despite broadly agreeing with your conclusions and thinking it's important. 

comment by tslarm · 2022-02-24T12:02:11.986Z · LW(p) · GW(p)

> Convincing a million 20-year-olds to sleep an unnecessary hour a day is equivalent, in terms of their hours of wakefulness, to killing 62,500 of them.

I thought specifically about how to phrase the last sentence in order for it to be only about facts rather than accusing anyone and the "convincing a million 20-years-olds" appears clearly to be just a thought experiment to me.

For what it's worth, I baulked at that sentence too. If you want to avoid the extra connotations, you could phrase it more like "...will cause them collectively to forgo 62,500 lifetimes' worth of waking hours". (Hopefully something less clunky than that, though.)

edit: to clarify, my issue was with the comparison, not with the implied blame. Although you explicitly claim equivalence only 'in terms of their hours of wakefulness', to me as a reader it seems like you are doing one of two things with that sentence: either suggesting that causing a million 20-year olds to sleep an extra unnecessary hour per day is, in terms of overall badness, somewhere in the ballpark of killing 62,500 of them; or making the comparison for no good reason other than rhetorical shock value, knowing that it is technically defensible due to the qualifier ('in terms of their hours of wakefulness'), but only because that allows you to brush over the differences between extra sleep and premature death.

comment by frankybegs · 2022-02-27T22:21:10.007Z · LW(p) · GW(p)

You specify a style for citation! By your own logic, this should be of academic-level rigour, surely? Pleading 'oh it isn't supposed to be convincing' is the exact same motte and bailey that Matt Walker is doing with his pop-sci that he self-cites.

This is an amazing bit of work, and one of the main reasons I come to LW is to find interesting, well-supported arguments that make me revise or at least question what I believe about important stuff. This does that, and I want to send it to everyone I know. But it's hard to do so when you undermine your credibility at points (in basically the ways that All-American Breakfast has outlined).

People are going to be motivated to preserve their dearly held beliefs about sleep, and you give them unnecessary ammo to dismiss you as an internet crazy.

comment by ChristianKl · 2022-02-23T23:43:21.335Z · LW(p) · GW(p)

Psyop is a word that you find in Qanon discourse but seldom in mainstream discourse.

comment by ChristianKl · 2022-02-22T19:11:53.393Z · LW(p) · GW(p)

There's a difference between a field where we have clear evidence that one of the senior scientists in the field falsified data and afterward he lost status for doing that and a field that just doesn't care. There's misbehavior by the people who allow Walker to give a keynote speech despite him making up a lot of claims in his book. 

I'm very interested in the idea that most of the negative recorded effects of sleep deprivation are caused by sleepiness, not sleeplessness. However, there are some effects that you cannot attribute to sleepiness, like hormonal changes

If you read the comments then guzey specially advised against changing sleep schedules by multiple hours in a single week the way that happened within that study. 

Making an intervention for a single week tells you little about what happens in people with chronic exposure to the same conditions.

comment by JonasMoss · 2022-02-23T13:41:51.084Z · LW(p) · GW(p)

About that paper.

The p-values relevant for testosterone are on the lower side, with one them 0.049 (which screams p-hacking) and another at 0.02 (also really shitty). A reasonable back-of-the-envelope method to correct for p-hacking and publication bias involves multiplying the p-values with 20 (the reasoning is not super-involved. think about what happens to the truncated normal distribution in the case of complete publication bias); in that case, none of the testosterone-related p-values in said paper are significant. I feel comfortable ignoring it.

comment by 860214 · 2022-02-14T16:44:02.183Z · LW(p) · GW(p)

I find myself agreeing with most of his premises. Except that sleep and memory arent really linked. From experience as a pianist, one can play a difficult passage on the keyboard and get stuck one day one, stop to sleep, and on day two have an accelerated mastery that wasnt present at the end of day one. it's integration of these actions/skills specifically during sleep and probably dreams, so it is muscle memory, somewhat unconscious, yet still a kind of memory, yes? I swear by the truth of this, from personal experience.

Additionally, having been depressed from age 4, from age 7 i would typically compensate by staying up late at night reading. I did not know this is what i was doing, but the sleep deprivation led to problems with mania in my teens and twenties, when i started to confront somewhat serious mental problems. (I am not diagnosed manic-depressive). To this day i have issues with managing my sleep. It's not that i am not tired or cant fall asleep. I love to sleep and it is wonderful. It's just that often I crave the dopamine or whatever neurochemical from novel experiences remaining awake. This is expressed as a desire not to miss out on experiences. It could be partying late when younger, but these days could be expressed as staying up to watch youtube videos.

Just some thoughts bc your piece really spoke to my experience and I wanted to weigh in. So this writing I really appreciated. Thank you for producing this.

Replies from: guzey
comment by guzey · 2022-02-14T16:58:21.748Z · LW(p) · GW(p)

Thanks! Very interesting. Have you experimented with sleeping vs staying up all night resting to see if it's sleep or just passage of time that helps with consolidation?

comment by Maxwell Peterson (maxwell-peterson) · 2022-02-12T06:23:32.769Z · LW(p) · GW(p)

This is FASCINATING. I sleep a natural 9 hours per night and still often feel quite tired throughout the day. (Setting up a sleep study with doctors this month but I barely snore, so doubt it’s apnea). The idea that I could maybe do just as well on 7 hours or less is very exciting and I’ll be trying it right away. I have a lot of problems with mental tiredness lasting throughout the day; I have been thinking about my sleep a lot lately and have noticed that even when I do rarely sleep 6 hours or so, my mind can still be awake even while my body feels tired.

In support of the possibility of habituating to less sleep: I had a roommate long ago, who was around 30 years old, and slept around 6 hours a night. I asked him how he did it, and he said something like “I used to sleep more, but then there was a period of my life when I didn’t have the time to sleep more than 6, and after that period passed, I found sleeping 6 hours and being fine remained something I could do.”

Even having heard his story, I’d never considered anything like the ideas advanced by this post. I don’t know whether sleep restriction will pan out for me, but even the possibility is just so nice to have as something to try. Thanks!!

Replies from: sil-ver, guzey
comment by Rafael Harth (sil-ver) · 2022-02-12T09:12:25.353Z · LW(p) · GW(p)

Another datapoint: I've experimented with sleeping as long as my body "wants" to as e.g. Matthew Walker recommends, which also is around 9 hours. I'd describe the results as disappointing, was probably slightly more tired and not really more productive.

On the other hand, evidence strongly suggests that 5 hours isn't enough.

So far, the rythm that felt best and led to the highest productivity was sleeping from midnight to 3:20 and from 5:40 to 9:00, but this is currently not possible because I sometimes need to get out earlier than 9:00. Alternatively, just setting the alarm for around 7 hours also does pretty well.

comment by guzey · 2022-02-12T09:44:20.235Z · LW(p) · GW(p)

Please be cautious and do not try cutting your sleep from 9 hours to 7 hours right away.

If you want to try experimenting with how much you sleep, try 8:30 and see how it goes first, make gradual changes, make sure you feel good, and take naps.

Replies from: maxwell-peterson
comment by Max Ghenis (MaxGhenis) · 2022-02-12T05:53:57.994Z · LW(p) · GW(p)

Thanks for this post. To clarify, it sounds like your thesis is about duration of sleep, not quality of sleep? How's the evidence for sleep quality and life outcomes? (And what interventions improve it?)

Replies from: guzey
comment by guzey · 2022-02-12T09:42:29.196Z · LW(p) · GW(p)

I have not looked into the evidence of sleep quality and life outcomes unfortunately.

Replies from: bfinn
comment by bfinn · 2022-03-02T10:24:36.473Z · LW(p) · GW(p)

Some years ago I did read research showing that improving sleep quality was the easiest intervention most people could make to improve their happiness. (I don't recall where, but googleable no doubt.)

comment by Bohaska · 2023-12-06T12:07:01.925Z · LW(p) · GW(p)

So, most people see sleep as something that's obviously beneficial, but this post was great at sparking conversation about this topic, and questioning that assumption about whether sleep is good. It's well-researched and addresses many of the pro-sleep studies and points regarding the issue. 

I'll like to see people do more studies on the effects of low sleep on other diseases or activities. There's many good objections in the comments, such as increased risk of Alzheimer's, driving while sleepy and how the analogy of sleep deprivation to fasting may be misguided. 

There was a good experiment presented here, where Andrew Vlahos replied

> I'm a tutor, and I've noticed that when students get less sleep they make many more minor mistakes (like dropping a negative sign) and don't learn as well. This effect is strong enough that for a couple of students I started guessing how much sleep they got the last couple days at the end of sessions, asked them, and was almost always right. 

and guzey replied with a proposed experiment

> As an experiment -- you can ask a couple of your students to take a coffee heading to you when they are underslept and see if they continue to make mistakes and learn poorly (in which case it's the lack of sleep per se likely causing problems) or not (in which case it's sleepiness)

Hopefully someone does bother to do it in the future. 

 


 

comment by Leosha Trushin · 2023-09-30T11:18:39.901Z · LW(p) · GW(p)

noting that sleeping 1.5 hours per day less results in gaining more than a month of wakefulness per year, every year.

 

This is wrong. 1.5 * 365 / 24 ~ 22.8 days. I think this comes from the 33 days of life every year statistic later on, which is based on sleeping 2 hours less per day.

comment by bfinn · 2022-03-02T10:13:31.834Z · LW(p) · GW(p)

Re sleep deprivation inducing mania, I sometimes fast (either on 100kcal or 700kcal per day for 5-6 days), and find (as others do) that after a day or so I go into a hyperactive state - very alert, clear-minded, energetic, probably not far from mild mania. (And unlike as described in the OP, I don't get hungry at all - or rather, only did the first couple of times I fasted. So it presumably it just takes getting used to.)

So I wonder if the analogies between sleep and eating are even closer than suggested.

comment by bfinn · 2022-03-02T10:09:18.570Z · LW(p) · GW(p)

Re the analogy with fasting, more broadly this would be an example of hormesis, i.e. the principle that many sources of stress are beneficial in small quantities. (As others mentioned, though they didn't use the general term.) Other examples include:

  • mild toxins, such as spices and bitter flavours (thought to be the evolutionary reason we like them, if in small quantities)
  • heat & cold, e.g. saunas and cold showers
  • mild diseases - hence vaccines
  • radiation, which curiously seems to reduce cancer risk in low doses.

Sleep deprivation may be somewhat different as it's an example of largely psychological stress, and I don't know if other psychological stressors are thought to be beneficial. (Except for the traditional belief that British public schools with tough regimes were 'character building', which is why Prince Charles was sent to Gordonstoun!)

comment by Bhuvan Mehta (bhuvan-mehta) · 2022-02-15T17:07:26.690Z · LW(p) · GW(p)

Very very nicely written. As someone who suffers from sleep apnea and is incredibly curious about sleep this was a fantastic read. I would say one thing I am not sure you pointed out because I skimmed the apendix part is sleep quality. If you have poor sleep quality you will sleep more and feel tired, thinking you need more sleep. If you have good sleep quality you can get by with less sleep or more variance in your schedule. If you have sleep apnea you are looking at heart disease -> death if you don't sort out your sleep hygeine. 

comment by NormanPerlmutter · 2022-02-13T01:06:29.392Z · LW(p) · GW(p)

I'm curious to learn more about the thesis that caffeine or other stimulant use can completely mitigate the effects of sleep deprivation until 30+ hours without sleep. My own (subjective, anecdotal) experience with caffeine is that occasional (once or twice a week) caffeine use fairly effectively mitigates occasional sleep deprivation if I got say 5-6 hours of sleep the night before as opposed to my preferred 7-8, but is not too effective if I slept less than 4 hours the night before.  The more often I use caffeine, the less effective the caffeine becomes, and that furthermore, during periods of time when I use caffeine regularly (say a cup of coffee every day), I get a time several hours after I have my coffee when I have a "caffeine drop" and feel sleepy, so that my overall productivity isn't much better than if I had no caffeine. I haven't tried dealing with this by having several cups of coffee a day.  That might work with regard to productivity, but I expect the side effects (jitters, energy/crash cycles, difficulty sleeping, and also reduced sensitivity to caffeine negating the euphoric effect of occasional caffeine consumption) would be quite unpleasant to me.