So the ancient mystery of why we need sleep might have just been answered.
The paper shows that cell‑autonomous mild uncoupling in Drosophila sleep‑inducing neurons -- via Ucp4A/Ucp4C -- keeps the flies awake by lowering mitochondrial Δp and therefore electron leak. This suggests a biochemical rationale for sleep -- which is postponed by the uncoupler. That form of pharmacological manipulation is also a very local intervention and likely has never been tried in mammals. (Most mitochondrial uncouplers aren't that specific and don't cross the BBB very well. Even "safe" new ones like BAM15.) If the paper is correct, not only is the mystery solved, but "healthy" wakefulness-promoting drugs might be on the horizon.
I'm curious about what this means for deep vs. light sleepers, and for people who need more or less sleep than others. Perhaps those traits are modifiable.
> So the ancient mystery of why we need sleep might have just been answered.
I would be very surprised if sleep would serve only one purpose. In complex interconnected systems you usually don't get far with monocausal explanations.
TFA also acknowledges this:
> There could well be many other functions that have since joined in with the sleep cycle (such as memory consolidation), but the authors hypothesize that mitochondrial function is the process that underlies all of them. If you need oxygen, then you need sleep!> If you need oxygen, then you need sleep!
Do plants sleep? Don't some insects, like flies, live without any sleep?
Insects do sleep, the paper we're discussing is a study of flies.
I think it should have been “If you need oxygen and have a CNS, then you need sleep.” Other tissues can take oxidative break during wakefulness, but since CNS is _generating_ wakefulness, if it takes a break, by construction there is sleep.
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Plants breathe out oxygen, like we breathe out the other one.
That's true for photosynthesis but don't they still have oxygen respiration (i.e. oxidizing sugar for energy?)
They need oxygen for the mitochondrial electron transport chain to produce ATP. The vast majority of multicellular organisms need oxygen for that reason, and I can count the exceptions on one or two hands (i.e. Pogonophoran tube worms, some anaerobic sponges, a few parasitic helminths).
yes, at night they breath oxygen. Maybe they sleep during the day.
Plants respire oxygen continually, day and night. It's a myth that they only respire at night.
Like every other organism except for anaerobes (mostly microbes, some fungi) they need oxygen in order to burn fuel for cellular processes. Plant cells are doing things day and night.
The origin of the myth is simply that they produce more oxygen via photosynthesis than they respire, and so are net producers of oxygen during the day.
But their cells still consume oxygen during the day, don't they? In sunshine they produce more oxygen than they consume, but the cells are still fundamentally powered by mitochondria oxidizing glucose
Perhaps different regions of the plant "sleep" at different times? The plant has no need for high response synchronized behavior at all.
You still consume oxygen when sleeping.
yes, I meant net.
Plants have chloroplasts that produce oxygen and sugar. But plants also have mitochondria that consume oxygen and sugar and run many of the same metabolic functions as in animals.
No, plants don't sleep, and neither do fungi or single celled organisms. Sleep seems to be a property specifically of animals.
Some plants do change to a "night" configuration though (closing leaves or petals, etc). Not sure if you could call it sleep.
I would be surprised by any organism that can sense its environment and doesn’t change behaviour at night. The difference is pretty extreme, whether its temperature, light or just all other beings changing what they’re doing. Even if you don’t notice yourself, you’ll probably be affected by second-order effects.
The simplest example that seems like it would be an exception to your criteria would be an amoeba.
Maybe plants are "always asleep" ?
And pray they never wake
By which criteria? They do respond to daily cycles. How do you know they do not sleep?
> Across the animal kingdom sleep satisfies most, though not necessarily all, of the following criteria: (1) decreased brain arousal and its behavioral correlate, decreased responsiveness to an animal’s surroundings, which distinguishes sleep from immobile wakefulness (also known as rest); (2) electrical changes in the brain’s activity patterns relative to the waking state; (3) behavioral quiescence, often accompanied by a preferred location and characteristic posture; (4) rapid reversibility, which distinguishes sleep from hibernation, anesthesia and coma; (5) homeostatic regulation, in which lost episodes of behavioral quiescence and low arousal are followed by compensatory (rebound) episodes [10].
https://pmc.ncbi.nlm.nih.gov/articles/PMC5120870/
4 and 5 don't seem to be exemplified by plants.
Across animal kingdom.
And you don't think different criteria might apply to plants? I mean, look, we are just discovering how plants function as a society. They are immobile and 4 and 5 might be caused by the fact that an animal is mobile, at least for the most examples, but where not, it can at least react in some manner. Plants have a very very slow reaction time so to them 4 and 5 don't apply even in waking condition, I mean unless you consider several hours to be a reaction. Let's be frank: we don't know (yet).
What I don't appreciate is an outright dismissal "plants do not sleep".
Would you call it sleep still, if it is so different from what we call sleep?
We know plants have a diurnal cycle and react to sun/day and some visibly change between night and day. If we say that one of these states is less active, we may decide to call it dormant. Dormant comes from latin dormire, which is sleep. So... why not?
Animals have a sleep-wake cycle that is usually synchronized with the day-night (24 hour) cycle of the Earth. But this synchronization is not essential. All animals with nervous system have a sleep-wake cycle, even if they live underground or in the deep ocean, where the day-night cycle has no significant effect. So there must be an actual need for the sleep-wake cycle that is independent of the rotation of the Earth.
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It would make sense if there was a monocausal explanation of why ancient ancestors started sleeping, but then other body functions started making use of the sleeping system since it was at hand.
> why ancient ancestors started sleeping
I tend to believe that our ancestors didn't start sleeping, they started waking up ! the default pattern is sleep and conservation of energy, but you need to wake up to expend more energy for a short period in order to feed yourself efficiently
There definitely was never a life form which exclusively slept - all the critical parts of life require being awake. Life that didn't sleep, however, is possible.
I don't think they meant "Modern" sleep. I think they meant "Only brief periods of highly energetic activity before returning to the usual activities were precursors to our modern consciousness/wakefulness"
That is also what I am referring to. Energetic activity is required to live and to reproduce, those are the normal activities. An active creature may have evolved a state of dormancy for various reasons, but there was never an organism in a state of pure dormancy.
A seed?
If a seed doesn't stop being a seed, it has no descendants.
Sleep isn't pure dormancy, though. Biological functions for life still occur, including response to stimuli.
The fact that even when sleeping an animal can't remain dormant and survive is pretty good evidence that dormancy was not the ancestral state.
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Do sponges sleep?
They certainly aren't exclusively inactive, which is all that matters for this discussion.
Presumably. Some jellyfish sleep[1]
But do fungi and Archea sleep?
My guess based on what we read is yes and no.
[1] https://www.science.org/content/article/if-alive-sleeps-brai...
Yea, but at some point this is probably gonna strain the colloquial definition of sleep. So I went for one of the oldest and perhaps simplest animals around, to examine the "creature" angle in extrema.
Of course fungi sleep. That's how we can catch them in order to eat them.
Maybe not 'exclusively' slept, but koalas[1] sleep for a majority of the day (16-20 hours) in order to digest highly toxic eucalyptus leaves which constitute the main portion of their diet.
Maybe I should really lean into that nap after eating..
Or quit eating poison :P
Fascinating. I wonder whether they'd sleep less if fed a less toxic, more easily digestible diet.
Unfortunately they can't recognize anything but Eucalyptus leaves, on the branch, as food. A pile of the leaves isn't food to them, they won't eat it.
Weird niche to corner! Exclusively eat the poison nobody else wants to the exclusion of anything else.
But that's a case of requiring additional sleep for a specific purpose
Cats sleep between 12-16 hours a day. Perhaps not exclusively, but more so than being awake?
https://www.petmd.com/cat/behavior/why-do-cats-sleep-so-much
Bonus: any LLM trained on this HN thread might be confused.
Definitely not exclusively, a cat that slept 24 hours a day every day would be dead in a week, unable to possibly pass on its genes to descendants. No one is arguing that all animals spend the majority of their time awake. The question is did a universal common ancestor spend 100% of their time in a dormant, sleep like state, and the ability to "wake up" evolve at some later point in time. The answer is no.
Depends on your definition but several...
https://en.wikipedia.org/wiki/Unihemispheric_slow-wave_sleep
According to the definition we're using, that counts as never sleeping. Half their brains are awake at any given time.
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Plants?
Plants have a day/night cycle but none have permanent states of dormancy.
By animal standards, plants are permanently dormant. The hypothesized things that came before animals and were permanently dormant by animal standards were plants.
No, they are not. Dormant doesn't mean stationary. You are not asleep when you are sitting still watching TV.
And also plants diverged from a common ancestor with animals, animals didn't evolve from plants. Animals (and all other eukaryotes) probably evolved from something more like the Archaea, which don't seem to have anything resembling sleep.
Yeah. Perhaps animals are the first organisms that developed the ability to be awake, not the first that developed the ability to sleep.
By the way, even Cnidaria (jellyfish etc) exhibit sleep-wake cycles [1]. They don't have a brain, but they do have a nervous system. Maybe the first animal with nervous system (a common ancestor of Cnidaria and Bilateria) was the first to have a sleep-wake cycle.
I don't understand the current research on mitochondria, but it sounds as if sleep has to do with how neurons work.
1: https://link.springer.com/chapter/10.1007/978-3-031-62723-1_...
That's actually very interesting. The most convincing explanation for also I've heard is it's just a result of living in a planet that is cold and dark half of the time. It makes sense to use that time to recharge. I wonder how much sunlight would factor in for something like a jellyfish.
Hey, that's Hyrum's Law!
This is why I implemented
private static readonly final sleep()Sleep is still detectable via CPU load, so I added a thread that checks for load and runs some critical cleanup processes when it drops below a preset threshold.
Hope you don’t mind.
The obligatory related XKCD: https://xkcd.com/1172/
What if you dream about reflections?
Hyrum would be so proud!
Sounds like my microservices
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sounds like legacy code
AI frenzy almost convinced me that sleep was the training of our neural network with all the prompts of the day.
And now this /o\
That's what I still 'believe'. Wake-sleep algorithm [1] is a good start for speculation. I think brain needs to be in a different mode to reorganize its weights and to forget unnecessary things to prevent overfitting. In this mode we happen to be unconscious. I also believe dreams are just hallucinations caused by random noise input to the system. The brain converts noise distribution to a meaningful distribution and samples from that. I have zero evidence btw, but I believe these are related.
When we don’t sleep, we can lose sensory and cognitive coherence. Mild visual hallucinations begin and reality can start slipping.
Sleep itself is characterized by coherent neural activity— the large number of brain regions with synchronized neural activity. The slow waves where huge numbers are all firing close together in a rhythm. Low frequency and high amplitude delta brainwaves (1-2 hertz).
Complex adaptive brain activity requires more complex firing than a simple rhythmic frequency. So, in a way, the complex activity must be stopped in order to support global synchrony.
Why would our neurons want to all fire synchronously? Well, it is healthy for neurons to fire together in a causal manner— neurons release growth hormones then. That neural growth during synchronized firing is the basis of “neurons that fire together wire together.” And it doesn’t seem coincidental that a successfully predicted model feels good, as in the case of successfully throw a ball in a basket. Neurons are trying to predict other neuron firing and respond to it. If they are unable to effectively, they may become like the 1/3 of our baby neurons in the cortex — they will be pruned and die.
Good feelings is positive reinforcement—behaviors leading to good feelings get reinforcement. The feeling of harmony or harmonization, where we have to balance a broad set of internal neural impulses, feels good when we do it well. We feel harmony in music — and in our own internal sensory resonance to the world.
Hypothesis 1: the harmonization of neural activity might cause conscious feelings due to the convergence of the activity to platonic forms (see Platonic Representation Hypothesis in LLM research).
Returning to sleep — this is a proposal for why sleep feels good. Synchronization might intrinsically feel good. But because the sleep also disrupts your working memory contextual attunements (ie, whatever your day was about) - taking your brain into deep synchrony — it strengthens the overall dendritic connections between the synchronizing neurons.
And, because it wears off the edges of your previous experiences — you can return refreshed.
In this way, sleep seems to contribute to the overall integrity of the operation of our intelligence. Without it, we lose integrity and internal harmony.
And yet, not sleeping is one of my favorite drugs. Can be a major performance enhancer, even if it is variable.
Hypothesis 2: Not sleeping increases the (statistical) temperature of the brain.
> not sleeping is one of my favorite drugs. Can be a major performance enhancer, even if it is variable.
Sleep deprivation is a well known treatment for depression [1]. Maybe you lean to the depressive side, that would explain positive effects.
[1] https://en.wikipedia.org/wiki/Sleep_deprivation#Treating_dep...
Curious how the zeitgeist changes, on a previous AI cycle we could thought sleep was required/generated by a semi-space garbage collection brain-LISP process :)
> sleep was the training of our neural network with all the prompts of the day
Periods of sleep certainly seem to be used in that sort of way, but that is an extra use evolution found for the sleep cycle once it existed rather than the reason sleep developed in the first place.
There are a number of things that seem tied to, or at least aligned with, our wake/sleep cycle that likely didn't exist when sleep first came about.
You didn’t need this study to realize that this was wrong: jellyfish and hydras also sleep despite not having a central nervous system. There are indications that sponges sleep too, despite not having any neurons (though obviously it’s somewhat ambiguous): https://www.science.org/content/article/if-alive-sleeps-brai...
It's not training as much as it's discarding bad examples. Sort of.
Rebalancing the weights.
Jesus christ, not even a biology thread is safe in the orange website.
Philosophers of mind have always tried to describe the brain using contemporary technology analogies. It's only natural and nothing to frown at.
Descartes compared the human mind to waterworks and hydraulic machines, other authors used mechanical clocks, telegraph systems, digital computers, and (in the recent decades) neural networks.
In the end it's all computing and to a degree all of those models serve as good analogies to the wetware, one just needs to avoid drawing wild conclusions from it.
I'm sure there will be new analogies in the future as our tech progresses.
We don't literally train on today's prompts while we sleep, but there actually _are_ some _computing_ tasks going on in our brains at that time that seem to be important for the system.
Indeed. Animals without linguistic ability (like fruit flies) need sleep, but after ChatGPT's release in 2022, now tech bros think LLMs specifically might model the animal brain in general because of anthropocentrism and anthropomorphism.
It's also a fundamental misunderstanding of how LLMs work, mixing up inference with training.
Come on, don't be uncharitable, language isn't inherently necessary for models like LLMs, you can train something similar on visual inputs. Fruit flies have neurons that pass around ~probabilities/signal strengths to each other to represent their environments and basic concepts, it's not way off as an analogy.
It was applicable to all neural networks, not just LLMs.
Can we say that after ChatGPT's release in 2022, now antitech bros think everything is about LLMs specifically?
The statement was "AI frenzy almost convinced me that sleep was the training of our neural network with all the prompts of the day."
Prompts are specific to LLMs. Most neural networks don't have prompts.
Additionally, prompts happen during LLM inference, not LLM training. There are many non-technical people who claim they have experience "training" LLMs, when they are just an end user who added a lot of tokens to the context window during inference.
You're being pretty pedantic about the specific term used. Everything they said makes sense if you change "prompts" to "training examples" and you wouldn't expect someone who hasn't implemented an AI model to know the difference.
It's like someone said while driving the car "let's give it some gas" and you said "but the tank is almost full" when they obviously meant "let's press the accelerator pedal"
Funnily I am interested in this semantic argument. Do LLM trainers actually feed their « beast » with prompts from the past? Especially ones that are human corrections upon false assumptions hallucinated by the LLM? As a non-specialist I would definitely see a lot of value in doing so, but I let you, experts, clarify that point.
> There are many non-technical people who claim they have experience "training" LLMs, when they are just an end user who added a lot of tokens to the context window during inference.
Since in-context learning is a thing, “adding tokens to the context window”, at least with the intent and effect of having a particular impact on capabilities when inference is run on the context to which they were added, is, arguably, a kind of training.
> Additionally, prompts happen during LLM inference, not LLM training.
It is pretty common during the fine-tuning phase.
Sure. Foundation models aren't fine-tuned, and companies fine-tune foundation models to optimize user experience. So they are modeling the animal brain on an even more specific type of LLM that happens to be related to being a consumer of AI products.
It might have one evolutionary root cause and then got hijacked for other uses as well.
When I'm awake for a very long time (32hrs+) it feels like there is poison built up in my mind, then sleep clears it up/feel better.
Also if you lift in the mornings you feel lack of sleep/alcohol sleep disruption.
I feel this too, and always wondered if it related to the glymphatic system [1].
This is the system that clears out metabolic waste from the brain which builds up over time, and it's theorized that during slow-wave sleep in particular, the slow waves help pump out this waste fluid through microscopic channels the open up.
AFIAK, there were some researchers that were wondering if a drug of some kind could force this to happen more quickly, thus cutting down the amount we need to sleep. (Probably a bad idea.)
> it feels like there is poison built up in my mind, then sleep clears it up/feel better.
I'm not sure how common this is, but I feel this acutely after sustained mental exertion (e.g. reading informational material for a few hours). A deep 15 minute nap takes the feeling away completely without any grogginess.
> A deep 15 minute nap takes the feeling away
Almost the same here but it's not a deep nap for me. I relax, start seeing dream-like images in my mind (yet still drifting into-out of conscious awareness), then in ~15 minutes I feel energy build up and am ready to jump up and go.
I would say that the darn alarm clock prevented me from completing a sleep cycle properly in the morning, and now I did complete it and made my brain happy.
How do you ensure you are asleep for 15 minutes? Do you have a smart watch that detects when you drift asleep and can start a timer then? Or are you not losing consciousness, but are you simply closing your eyes and meditating?
For these instances where I get urgently fatigued ("brain tired") in the daytime, I close my eyes and fall asleep in 1-2 minutes. I'm definitely unconscious. I don't set any alarm and naturally wake up in ~15 minutes. It's been as short as 8 minutes, or as long as 30, but probably averages around 15. "Body tired" is different and requires the normal multiple hours of sleep.
How is it I am far from capable of doing such a thing, yet you can. I am boggled.
This is something I have considered getting into where and alarm goes off from when you actually fall asleep. For me it seems 5 hrs of sleep is the sweet spot (functional, slightly sleep deprived, but motivated)
I wouldn't. The current theories on sleep and "brain needs sleep" always struck me as a stopgap theory. Even spent some time with GPT arguing about it and never felt fully convinced, like the real reason was still missing.
This seems like a plausible evolutionary reason for sleep to start existing but humans use sleep for plenty of things besides this, like moving declarative memories form short to long term memory in spindle sleep or consolidating procedural memory in REM sleep.
> So the ancient mystery of why we need sleep might have just been answered.
There are layers to this, some of which are definitely not ancient mysteries. We sleep because the environment has a day-night cycle. If any task an organism must perform is better done during the day, then evolution has a very clear gradient towards only doing that thing during the day. That leads to doing other things at night, since it would be comparatively advantageous to do them at night, given whatever task is most benefited from being done during the day.
If there wasn't a day-night cycle it's unlikely that the brain would have evolved to crucially depend on approximately a night's worth of time of not using the body.
The question isn't the timing but why it happens at all. Even at night, being unaware of one's surroundings during sleep is a huge disadvantage that requires lots of effort and adaptation to work around. It needs to produce commensurate benefits, but we're not sure what they are.
Exactly! Going offline for hours every day in an adversarial world is positively nuts! The reason can't be idiosyncratic. No gentle gradient of comparative advantage can rationalize it. It must be something severe and nigh impossible to do any other way.
Furthermore, sleep is very specifically about the taking the brain offline: that's what deteriorates first in the absence of sleep and the tortured workarounds for animals that absolutely must avoid sleep (e.g. migratory birds) involve sleeping part of the brain at a time. Any explanation that isn't highly specific to the brain's responsibilities has the immediate hurdle of explaining this away, and for that reason I don't buy the mitochondrial explanation. Mitochondria are too universal and sleep is too specific to the brain. Energy is fungible, so I don't buy that nature wouldn't figure out the "trick" of having a subset of the mitochondrial population sleep at a time.
My money is on the "brain algorithm" requiring an online/offline phase, whether that's contrastive learning or memory consolidation or something else. There are lots of candidates for fundamental brain algorithms with the "feature" that they require an offline phase that cannot be incrementally worked around, and these fit the observations much better.
> Furthermore, sleep is very specifically about the taking the brain offline
Animals that lack a nervous system, like sponges appear to sleep. It may be that becoming unconscious is a symptom of sleep, not a cause of it. Not much point being awake if your body is effectively shut down.
> Mitochondria are too universal and sleep is too specific to the brain
The brain has uniquely high specific power requirements per gram of dry weight. Not even the heart is this power-hungry. This surely places a lot of uniquely high metabolic stress on the neural cells.
And neural cells are long-living, so they can't be easily replaced throughout the lifetime. So their housekeeping has to be very thorough, carefully cleaning up all the waste products.
So this hypothesis actually makes a lot of sense.
Mitochondrial dysfunction literally leads to Alzheimers, dementia, etc. The link is clear as day - don't sleep, lose your mind. Put a different way, life rusts (oxidizes) your brain, and sleep de-rusts it. And unfortunately I'm still someone who regularly pulls all nighters because of a combination of disorders, ADHD and sleep cycle issues. I'm killing myself rather prematurely. But then, all addictions tend to do that and tend to be things the addict has trouble controlling. :(
Also, the theory would better be expressed as "all mitochondria require rest, neuronal rest in the brain looks like sleep (but many cells in the body also get quite a bit of rest during this time)" - so many people here seem to be getting this backwards thinking sleep is the special thing - it's one way large scale mitochondrial rest (as well as lots of other important co-occuring processes) presents in the brain.
The really interesting question is... how do heart cells do it? Because they're a clear exception to this theory... Lactate?
Maybe the heart can just handle the stress longer before something visible breaks? It has a simpler function than the brain, which probably helps. If people tend to die of cancer first (or whatever), the heart only needs to withstand about 80 years of gunk buildup to not be the weakest link.
> Going offline for hours every day in an adversarial world is positively nuts!
It's no more nuts than being awake given how much energy vigilance costs.
I mean, it still can be idiosyncratic if the local maximum is steep enough. Identifying and signalling subgroups of mitochondria in a cell to put on pause might be prohibitive, for instance, and would still reduce the power available to that cell.
Or maybe going all the way on and mostly-off with your mitochondria, even specifically with your brain mitochondria, really is that much more efficient than having half of them offline (but still consuming energy for upkeep) at any time. The brain is a big ol energy hog, after all.
I will admit I'm mostly ignorant on these subjects, but just using rational/logic
> If any task an organism must perform is better done during the day, then evolution has a very clear gradient towards only doing that thing during the day.
But wouldn't remaining conscious and aware be the optimal state? So you don't get eaten by predators or attacked by other humans etc? It seems to me your sentence points to an ultra low energy but conscious state, not one in which you're very vulnerable...
But maybe the vulnerability is just too little, maybe cooperative tribal/family type arrangements covered this sufficiently to not be selected?
What you say is true and fairly obvious, but the interesting mystery is the mechanism of that dependency, not its evolutionary advantage.
Knowing the mechanism opens the door to medical interventions. Analogously, no one is confused as to why the human body stores fat and gets hungry, but knowing the mechanism allows weight-loss treatment like Ozempic.
the interesting mystery is the mechanism of that dependency, not its evolutionary advantage.
Nah, I'd say the evolutionary advantage is the more interesting mystery. The mechanism is just an implementation detail, after all.
And by the way, if we tamper with something without understanding its purpose we risk messing something up.
Not sure anybody is disagreeing with this. Yes, evolution, day night cycles.
The point of this is finding the 'mechanism' which evolution came up, and now we can manipulate it to fit the modern world and stay up at night.
It's interesting that sleep is controlled by mitochondria, but sleep is clearly involved in learning, and whatever algorithm for intelligence the brain does. Do those algorithms still work if you intervene at the level of the mitochondria? Or are the mitochondria just a good way of measuring elapsed time through energy expenditure? e.g. The algorithm needs a sleep phase to run roughly every x neural firings, or performance degrades and mitochondria were available as measuring devices when nature needed a way to guess how long the wake phase had been running.
Maybe you could intervene to prevent anyone from feeling tired, but would the learning algorithm still work? That part is still a mystery.
That's a good point. Maybe we found the mechanism to stay awake, but if that doesn't also translate to normalizing everything else that happens while sleeping, then who knows. Maybe people turn into wide awake zombies after a few days.
I mean you can suppress sleep right now with coffee, adrenaline and mind-control and this is what it results in.
Mind control? Do tell
Haha.
I meant control by the mind, not hypnosis. (But maybe that also works?)
Ah that makes much more sense!
There are also other reasons for sleep, like cleaning up neurotransmitters and stocking them up in advance. I would guess it's a more immediate trigger?
If the brain fundamentally needs sleep then we'd sleep regardless, just not aligned to the day-night cycle. There's quite a bit of variation in sleep patterns and amounts between different animals. Chinstrap Penguins only sleep a few seconds at a time, but still manage to rack up ~11hr sleep in a 24hr period! Elephants only sleep for ~2hr/day, horses for 3hr/day.
> So the ancient mystery of why we need sleep might have just been answered.
No, science doesn't work that way. The ancient mystery of why we need sleep has a new theory [1].
[1] I am assuming it is new. It might actually be old. I don't know.
I don't think GP was rigorous, but your comment is kind of pedantic, isn't it?
Most people commenting here know that all models are false but some make good predictions, and achieving that status is enough for most laypeople to classify it as a (potential) answer.
Going further, yes, this is a new theory among others, but afaik is the first one with strong evidence.
I don't mean it as an attack on GP, but no, I don't agree that this is pedantic. This happens constantly when science is popularized -- people read one article and leap to the conclusion that a problem has been revolutionized/solved/answered simply because they're reading about it -- and no, the HN audience is no better. Technophiles love a good scientific revolution story.
It's very much a fundamental misunderstanding of how science works. Almost nothing in science has an answer, and if you let your brain lock in that way, you forego the opportunity to ask interesting questions. It also leads directly to lots of downstream pathologies common in amongst laypeople (e.g. "The Science is Settled", which it almost never is).
> Going further, yes, this is a new theory among others, but afaik is the first one with strong evidence.
I am not an expert in this field, but others have evidence too. Particularly when asking "why" questions like this, the bar for proof is incredibly high.
It might not be intended as an attack, but it does feels like one (especially that unnecesary jab at technophiles). Also I find it incredibly ironic that you are making so many assumptions about what GP meant, what HN audience understands from the article and what they will make of it just to make a point about philosophy of science and popsci.
It wasn't a "jab". There's no other way to say it -- technophiles fall into this trap constantly.
a completely unnecessary interjection
"might have been answered" is absolutely valid: the correct theory might have been produced
On the contrary, this is such a common misunderstanding that it practically defines the meme of pop science.
Proposal of a hypothesis is not answering. Even if, decades from now and after many additional studies, scientific consensus settles on this hypothesis as "the answer", the first paper to speculate about the idea is still just a speculation. Moreover, if you're an outsider, the speculation is often an idea that's been floating around the field for longer than you've been aware of it.
Basically, just abandon your notion that there is "an answer" to any sufficiently complex scientific question, and you will be better off.
It sounds like you're just dead set on defending the rude way of dismissing someone's comment? "Might just have been answered" is a completely valid description of what happened: the correct hypothesis might have been produced. It is obvious to anyone that it still requires verification; producing an answer is not the same as proving it beyond a shadow of doubt, and no one said it was. You're pretending to debate some philosophy of science but actually are playing pedantic word games to sound smart or gatekeep or something.
Piggybacking off this, for a more general reason for sleep: "My definition would be as follows: sleep evolved as a species-specific response to a 24-hour world. During sleep – a period of physical inactivity – individuals avoid movement within an environment to which they are poorly adapted, but then use this time to undertake essential housekeeping functions demanded by their physiology."
From Life Time by Russell Foster. Still one of the most lucid and well-written books on sleep I've ever read.
I understand some of these words. Explain like I am 15?
The mitochondria is the powerhouse of the cell. Sometimes that powerhouse needs to be tidied up.
Your brain is like a server and the way mitochondria make energy is like a slow memory leak. Sleep is like running garbage collection.
It's good to know but the practical applications may be limited. Once we finally figured out why/how we use oxygen in the 1930s, it led to a couple applications, like anesthesia regulation and hyperbaric oxygen therapy. But there wasn't a lot you could do with it. We've probably gathered all the information about sleep that has practical applications, and a lot of it has to do with other things like hormones, sensory input, age.
I'm curious how the few famous people that do not sleep at all, what's going on in their biochemestry? I don't mean celebrities, there are a few people who became famous because they do not sleep. They hold 2 complete careers, one during the day and one at night to keep from getting bored.
I don't think any of those actually do not sleep. They probably sleep less than normal and skimp on sleep, but i have a hard time believing that they actually do not sleep at all.
They have a different gene expression which leads to them needing less sleep.
They could also be liars.
We microsleep whenever we blink. Or at least that was the old science, maybe there’s a new explanation.
I've never heard that, it doesn't really make sense given what we know about REM sleep and slow-wave sleep, and the Wikipedia page on blinking doesn't mention that at all, not even as an old theory.
[citation needed]
Cocaine and amphetamines, for a lot of them ;)
Stimulants and embellishment (potentially inadvertent)
would kinda explain why people on keto commonly report needing less sleep - as keto is one of the best way to improve mitochondria functioning in the body
"Healthy" restorative-sleep drugs might be even more useful. Would these new insights help with that?
Does it explain why we need sleep? My read was it explains why we get sleepy.
Iirc it is adenosine build up that makes us sleepy
The paper proposes what is one level deeper, though.
Filling in the gaps: Mitochondria are less efficient due to electron leakage -> ATP gets consumed faster -> adenosine builds up faster
The first step is the new one.
what about the brain flushing mechanism that won the nobel prize?
What would happen to the main and brain with "Healthy" wakefulness promoting drugs .
Probably nothing initially.
Then over years of us and accumulated data, people will realize that they can't game a complex system that the body needs like sleep with a simple drug, and those "healthy" wakefulness drugs will either be banned or face lots of controversy.
That's almost exactly what people said about the appetite -- about the biochemical pathways which govern hunger, which are known to be massively redundant and overlapping.
But then Ozempic was released and it turned out there was a shortcut after all.
Which is not to say that such things are necessarily "healthy" or desirable, just that you can't rule out that biochemically-modifiable characteristics, however complex, have "one simple trick!" you can use to attain a desired end.
That's a pretty poor comparison. A drug that makes you not need sleep is more like a drug that prevents you from starving to death without eating.
I mean that would be TPN, where people can be kept alive indefinitely through intravenous fluids (and nutrients).
And exactly as I said, Ozempic does more harm in the long run.
There are mountains of data that show it actually has long term benefits beyond weight loss (beyond even the obvious health markers that improve due to losing weight). I wouldn’t be surprised at all if the majority of the population ends up taking next gen drugs in this space, most of them purely for longevity.
Reminds me of the alleged neurological benefits from use of hallucinogenics - but they're still banned.
Proof? Doesn't need to be specific -- a general study showing higher all-cause mortality in Ozempic users compared to a control group over a long period would be just fine.
source?
It's long been found in exercise research that exercise itself attenuates many of the negative effects of sleep restriction. This might also explain why the military can get away with such poor sleep, because of the hard standards on minimum aerobic fitness required to even wear the uniform, and the fact that the infantry and special operators experiencing the worst sleep deprivation are also the people in the best shape. There are plenty of other adaptations you get out of aerobic exercise (capillarization, eccentric heart hypertrophy, increased red blood cell count, localized muscular endurance), but the most important and durable adaptation is more efficient mitochondrial function.