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A little thing I realize upon reading about all the brain study is how bad we are at reverse engineering a totally alien "computer".
In popular media, human is often depicted as some super scavenger that can exploit and adapt alien technology to their own in a matter of 1-2 lifetimes. And yet here we are in reality, after thousands of years with abundant and intimate access to one of the most efficient and most capable information processor known to us, and we are still absolutely clueless about how it work.
The closest thing we built to mimic it cost maybe a million times more energy and perform a fraction of the functions of the original one. So much for "reverse engineering".
If you are comparing the energy cost of LLMs, consider that the "training cost" of the human brain is the accumulated evolutionary activity of the last 4 billion years.
Human inference is much more efficient though - we run at about 100 Watts[0], probably a lot less for the thinking alone.
[0] https://physics.stackexchange.com/questions/431522/humans-ha...
Remember, though that LLMs also need the accumulated evolutionary activity. They're not that interesting if you don't feed them human created content. Contrast that with the human computer that builds itself and then infers language and complicated physical and mental tasks.
Given I can do token generation on a 30 watt laptop, the language/Joule part at least seems to be the computer winning. (Separate to any discussion about quality).
Not so for images, as I can imagine visual scenes in what feels like real time, while even the fastest image generator I've seen was 200-300 ms at 512x512.
Part of the problem is that it's not really possible or ethical to truly observe and tinker with it while it's running.
I doubt we would have similar ethics concerns with a non-sapient alien computer, though we might have a more limited number of examples.
Biological systems are not "engineered" in the same way a computer is. Computer chips, despite all their complexity, are designed to be understood by humans - they are modular, and abstract-able to facilitate design. Biological systems do not have these properties unless it is advantageous for the task at hand. You often have systems where everything interacts with everything else in meaningful ways. So it isn't really accurate to directly compare reverse engineering technology to reverse "engineering" nature
Fortunately for us, we've prioritized medical ethics over reverse engineering.
can a computer be complex enough to comprehend its own complexity?
I’ve always considered dreaming to be a daily disk defragmentation process where they bolted extreme Winamp visualizations on top to make it more interesting.
I've always thought of dreaming as analogous to a flight simulator, as the article suggests.
Sleep might have multiple purposes.
There is some recent research that some chemicals are flushed through the brain during sleep to remove byproducts. Why that can't happen without sleep is another interesting question.
> Why that can't happen without sleep is another interesting question.
I would guess that since sleep has been optimized by evolution for a long time, and evolution is so creative, that there are now countless dependencies on that time/phase separation.
But umbrella reasons probably include all of these:
1. To recognize unhealthy build of material for removal, you have to stall normal production. Otherwise production and removal would waste each other's efforts and pernicious build up would be undetectable.
2. Some cellular machinery may be used during normal and clean up operations, in different things. Evolution is great at reusing whatever is available.
3. Sleep involves coordinating many systems. Some subsystems might technically be capable of operating more flexibly, but coordinating all the systems together makes overall coordination simple, efficient and reliable.
4. Sleep isn't low energy behavior. Segmenting energy use between waking and sleeping maintains a lower metabolism envelope.
5. Dreaming is high level behavior. Can't high level think and dream at the same time.
6. Dreaming sensory free, motor free, operation is fundamentally at odds with normal active sensory and motor activity.
7. A billion random dependences on phase separation have accumulated over millennia, at the psychological, gene, epigenetic and chemical level, with no pre-ordaned rationale other than the separation was dependable for the other reasons given.
Intersting that octopuses, whose brains are an entirely separate "alien" evolutionary invention, also appear to dream. [0]
[0] https://www.smithsonianmag.com/smart-news/octopuses-may-have...
Maybe the flushing of chemicals causes hallucinations (=dreams). Hallucinating when you're awake is typically a bad idea.
I wonder if this is heavily based on the fact that during sleep, all inputs are shut down. Like, you can't hear, you can't see, you can't feel, no smell, no taste. All senses to the outside world are off.
What is it about external inputs that makes the brain not be able to do it's sleep "duties"? Is it that external inputs take up processing power that needs to be used during sleep instead?
Because when we are awake our brains run "hot" producing chemical waste - evolving on a world experiencing predictable day and night cycles led to sleep - it is not like we could do anything without sunlight back then.
It was also dangerous to do anything i.r.o nocturnal predators.
In the article, the author writes:
> Why devote this kind of energy to the creation of wildly imaginative and highly emotional nocturnal experiences for an audience of one?
I think that this is a mistake. The audience size is greater than one.
The author also writes that dreams “[give] us outrageous scenarios so we can better understand the everyday, serving as an overnight therapist”. I believe this is a multiplayer game.
I am a psychotherapist (in training). When people report their dreams, they normally do not mention their own behaviour. However, when their behaviour is investigated it often looks odd given the “outrageous scenario” they are in. More specifically, the behaviour often reveals clear displays of their unconscious interpersonal anxieties that their waking symptomology only opaquely reveals. An example, might be someone who is “shy” when awake behaving in an outrageously passive way, when in a confrontation; a confrontation that their waking shyness - which might include symptoms which mean they avoid contact with others - would have meant that they would not have had. It is no surprise that people do not typically report their own behaviour within dreams, as that is the nature of unconscious beliefs - we think they are unremarkable and true. Often an outsider is required to notice that the behaviour is unusual given the “outrageous situation” - often the role of a therapist (who shares this theory on dreams).
In the paper linked below, I outline many examples of this, and discuss the surprisingly specific supporting neurology:
https://osf.io/preprints/psyarxiv/k6trz
This paper was discussed on Hacker News previously. The link to that discussion is:
I also agree with those who say that sleep has multiple purposes. REM sleep typically starts four hours into a sleep cycle, after the “deep cleaning” work seems to be done. This would suggest that the brain is prioritising its basic functioning over the discovery of unconscious patterns, which is, I believe, a sensible trade-off. It is not imperative that we spot our unconscious patterns, though in the long run, it can make a big difference to our lives.
What I liked about the whole lucid dreaming scene is that they already figured this out, but are using different terminology to describe it.
You are exhausted, not relaxed, after a lucid dream. And you always need a second sleep session with REM sleep after that.
But you make a lot of progress on internal reflections, because your subconciousness fills in the emotional blind spots your alter ego cannot grasp (yet). I think that's why a lot of people in lucid dreams can relate so much with the 2 systems theory of Daniel Kaneman, and why there's so much debate about it.
> The rational, executive network in the brain is switched off, and the imaginative, visual and emotional parts are dialled way up. As a result, the dreaming mind is given free rein in a way that has no parallel in our waking lives. We couldn’t think this way when we are awake even if we tried.
I read this and felt compelled to say this reminds me of how psychedelics like LSD and psilocybin work :)
There's a decent hypothesis about the reason for dreaming, but it's a bit absurd to call it the whole point of sleep.
As a person with severe insomnia, often going several days without sleep, you absolutely start breaking down without sleep. Brain zaps, hearing things, seeing things, etc. I've read people have even died in severe cases.
So it feels like there's a medical necessity that's the whole point. Whether dreams are a neat side effect of said process or a purposeful side project of sorts is worthy of debate, however.
Are you sure about people dying from lack of sleep ? I read the opposite but I lack proof. To me sleeping is an essential "maintenance" of the body & the mind but that lack of sleep wouldn’t kill you in itself.
However there is no doubt sleeping is essential to psychological and physical health.
I also sometimes struggle with insomnia and I recommend reading "Why we sleep". It helped me understand sleep better than I would have thought and it actually helped me manage insomnia. The book is also actually really captivating which is a good thing given I thought I knew enough about sleep hygiene. I was so wrong.
If I wasn't sleeping, that would be an emergency. Not sleeping will end a life.
Whatever is going on, whatever I was doing or not doing. I would (try to) sleep in a random field without any "need xyz for 3+ days (other than water and a multivitamin, fasting)" even if it's prescription or life assumption whatever. Just to see. Just to sleep.
Unexpected and unnoticed things can dramatically effect sleep.
To me dreams feel more like a side effect of sleep. The fact that one is asleep is the restful part. Dreams do give some insight, but often times I don't dream at all (as in I don't remember them) and feel really well rested as well.
Sometimes I only get by on power naps and those power naps are pretty good too.
If dreaming is the point, then my dog has mastered the skill. Until I met him I never considered dogs could dream so prolifically.
I wish I could plug a TV into his brain and watch the reel running through it.
Same with my cat. Every time I go to sleep it will always pick me to snuggle with usually in between my head and elbow. Within a few mins it’s purring and its limbs twitch and I get poked by claws. It’s in deep sleep and seems happy.
I have some pretty wild dreams myself, and what’s wilder is that I have those dejavue (sp?) moments regularly irl.
Yeah dogs are cute when they are dreaming. You can see them run in green grassy fields.
The last thing you would do is to interrupt this moment of happiness.
(Off topic : dogs are so good)
You don't know if he's dreaming really. He could just be twitching and shuffling in his sleep, without dreaming.
Interesting article.
> (...) given the many potential benefits of dreaming for our waking life, maybe it’s not the sleep we really need, but the dreams.
Waiting for the pot brigade to use that sentence as a conversation starter...
We need sleep to recover physically. Like really need it. Anyone who has done physical exercise or just work and tried to rest in other ways will learn that sleep is the best way to rest.
Also body cleans up (if not sleeping on full stomach, big mistake of mine yesterday but those 400g steaks were expiring...)
Pot brigade? I'm not sure what that means but nightly smokers aren't having many dreams.
If subjectively experiencing a dream were "the whole point" of sleep, that would make it pretty hard to explain why total sleep deprivation is fatal. Clearly there are far more important things going on physiologically during sleep.
Can dreams be therapeutic? I'd wager that happens just about as often as they're psychologically harmful. And both of those outcomes are far less frequent than completely forgetting your dreams.
A silly article.
Dreaming may be when the weights get re-trained.
I've read we rehearse things in our dreams. If we played tennis one day, we simulate playing tennis in our dreams that night, and the next day we are better at tennis.
I also kind of wonder - does sleep have an evolutionary function to not move and not make noise during the night to patiently pass the time of night predators?
I can't remember where but I read somewhere a theory that says that most of life started sleeping, in the water, this was the default state.
At one point in time stuff started being awake and developed wake consciousness, and the evolutionary pressure was on the wakefulness of things, because if one thing is awake everything has to be eventually.
It made me think - why are we thinking our wake life is real life? When we're asleep - we're sure the dream world is the real world.
It's like one life is not enough from an evolutionary standpoint. You have to have 2 lives, interconnected on 2 different dimensions, alternating day and night.
Link is broken (has an extra p at the end, sleepp rather than sleep) and ends up in a page saying "Sorry – we haven’t been able to serve the page you asked for.", here is it fixed
https://www.theguardian.com/books/2024/apr/22/the-big-idea-w...
@dang maybe you should fix the link?
Looks like The Guardian may have had a typo (-sleepp) in their url, fixed it, and didn't redirect traffic from the typo to the new url. Either way here is the working url:
https://www.theguardian.com/books/2024/apr/22/the-big-idea-w...
One thing I believe is that the less you're involved in fantasy, the more realistic your dreams are. So if you're a simple, practical man without beliefs in supernatural, your dreams will be about daily life; but if you read fantasy and have superstitious beliefs and watch a lot of movies, you will have more complex and bizarre dreams. I mean, it's hard to dream about something you haven't encountered.
"I mean, it's hard to dream about something you haven't encountered."
I guess it is very hard to not encounter fantasy in daily life (though most of it is marketed as reality).
Dreaming stopped for me after being put on Trazodone. In some the medication induces nightmares or vivid dreams, not for me. I can testify that dreams contribute a lot to the perceived quality of sleep. In recent months I've had a few very short dreams. They're dull, bland, nothing much happens. I feel robbed of a part of my life. I took Trazodone for about a year, now some 8 years ago.
Interesting. I take Trazadone to reduce the number of nightly awakenings. I still get up 3-4 times a night but at least that gives me the opportunity to make it through a sleep cycle without waking up.
Wear an Apple Watch to bed. See if you are sleeping continuously and entering deep sleep or rem.
Wow, sorry to hear. I'm going to tattoo that name, so to remind me to never take it.
Glymphatic drainage is the "point" (in the sense of "kill you if you don't do it").
And it's typical of evolution to use the behavior for several other purposes...
You have a typo in the url. Otherwise, very interesting article!
Seems that dreams are needed, but the article doesn't really give a good explanation why
Since the late 80s (when neural nets were a thing) I've figured that dreams are a way to "reweight" brain encodings: throw noise in, and the pathways to whatever strong signals come out probably ought to be reduced.
2-3g of lions mane mushroom before bed greatly enhances dreams and vividness, also happens to be easier to wake up, a more refreshing sleep