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Frozen human brain tissue was successfully revived for the first time (bgr.com)
164 points by amichail on May 18, 2024 | hide | past | favorite | 110 comments



Because 'lab grown self-organizing brain samples continue to grow after being frozen' is a little less appealing than the clickbait title


From the article: "The researchers also applied their technique to three-millimeter cubes of brain tissue from a 9-month-old girl with epilepsy. The tissue maintained its pre-freezing structure and remained active in a laboratory culture for at least two weeks after being thawed."


> and remained active in a laboratory culture for at least two weeks after being thawed

I’m sure I don’t fully understand the details but this kind of thing both excites and horrifies me when I ponder how much brain might be necessary to sustain the experience of consciousness.


My personal opinion is that it's not just about brain quantity. I think being embedded in an environment is necessary for consciousness. My argument is that there is no such thing as unqualified consciousness -- you have to be conscious of something. You're not born aware of yourself, you spend the first few years of your life figuring out that you are embedded in this thing called a human body that, with considerable practice, you can exercise more-or-less direct control over. After more years you figure out that your body is further embedded in a world full of other things that you have only indirect (at best) control over, or no control at all. Only after all that can you draw a line between you and not-you and become aware of "your" existence.


I would not equate self-awareness with the feeling of being enclosed in some distinct thing called a human body that you can exercise control over. With the latter you are not just self-aware, you are also deconstructing experience into parts according to a particular dualistic approach (“that is my body, this is me”). Such deconstruction may not be required, and whether it is the only or even the best approach to qualifying own being is dubious (some might say you and your body are the same and implicitly treating “you” as “contained in your brain” is a fallacy—from the perspective of natural sciences a good illustration is probably how gut flora changes, non-brain organ transplantation, and such correlate with shifts in your personality).


> how gut flora changes, non-brain organ transplantation, and such correlate with shifts in your personality

Well, yeah, but so what? You can have shifts in your personality and still be you. You can be grumpy one day and happy another and still be you. And those changes can be cause by environmental changes far less radical than organ transplants.

The one thing you cannot swap out and still remain you is your brain.


Organ transplantation personality changes are not about happy one day and sad another day.

> The one thing you cannot swap out and still remain you is your brain.

Wrong. You can also not swap out your body and remain yourself.

> You can have shifts in your personality and still be you.

When do you stop being yourself? What makes you yourself? Think about it—it is not an easy question to answer.


> You can also not swap out your body and remain yourself.

Why not? Even taking technological limitations into account, there is almost no part of your body that can't be swapped out even today. People have artificial limbs, artificial hearts, artificial ears. They get lung transplants, kidney transplants, face transplants. Give the technology a few more centuries and I don't see any reason why a complete body swap-out should not be possible.

> it is not an easy question to answer

Indeed. But most people would agree that you can get an organ transplant or an artificial limb or a hearing aid or wear glasses -- or any combination of the above -- and still be you. Not so for a brain transplant.


> Why not?

Want to try it?

> But most people would agree that you can get an organ transplant or an artificial limb or a hearing aid or wear glasses -- or any combination of the above -- and still be you. Not so for a brain transplant.

I do not think that is relevant in any way. Most people also believe in God; that does not make it a compelling claim.


Yet you can remain conscious in deprivation chamber. I feel that this approach is too high level to technical details how brain may really work.


But sensory deprivation chambers are both known to make people unconscious, don't completely remove all sensation, and still induce hallucinations reliably. The conscious entity has to be conscious of something, and if there's nothing it will create something to be conscious of.


Also, going into a deprivation chamber as an adult is very different from being raised in one.


> You're not born aware of yourself, you spend the first few years of your life figuring out that you are embedded in this thing called a human body

This is Piaget-level garbage.


Please, educate us. Why is it garbage? To me and perhaps others, this makes intuitive sense. Why shouldn't it take several years for an intelligence to build self-knowledge before it can develop what we call consciousness? Why shouldn't consciousness be emergent, as an intelligence slowly understands that it is limited to a physical form?


Why shouldn't it be baked into the neural structure that has evolved over the past half billion years? Why should it require years after birth to manifest?


You hope that people will realize what they're doing before they argue that normal children aren't conscious, but no.


The brain is not constant during this process however. It is developing at the same time.


Yes, well, that is one of the many reasons I hedged with "My personal opinion is..."


Is your opinion immutable?


Even the actual entire brain you have right now can't sustain the experience of consciousness during sleep, or while under the influence of sedatives, or during times of sudden trauma.


Have we even figured out how anesthesia actually works yet?


look into the Portia spider - fun rabbit hole!


Have you read "Children of Time" by Adrian Tchaikovsky? Because if not, you absolutely should.


I know! It's on my list.

I heard of it from Peter Watts, in Echopraxia (Blindsight is wonderful as well!)


Meh. If we want immorality we'll probably end up converting a brain scan to an LLM.

Medically this could be great for preventing brain damage.


ANNs can't represent everything involved with a functioning brain, never mind a highly specific ANN architecture. Any consciousness or similar would need to arise via an independent mechanism.


> Any consciousness or similar would need to arise via an independent mechanism.

Probably, but even then only due to there being a lot mechanisms and we don't know which of them is related to the subjective experience of existing that is the meaning of conscious I assume you're using here (there's something like 40 definitions of "consciousness").

But because we don't really know where the capacity for an inner experience even is, it's not impossible that even an LLM, which totally isn't designed with the goal of having it, might nevertheless have it.

(I really hope they don't, I statistically suspect they don't, I just can't rule it out).


It's not impossible that rocks have consciousness. Some modern philosophers advocating pantheism think they just might.

Meanwhile, according to Sabine Hossenfelder, a recent paper shows evidence that Penrose was right about quantum effects happening in the brain:

https://www.youtube.com/watch?v=R6G1D2UQ3gg


> Some modern philosophers advocating pantheism think they just might.

This is a terribly low bar. The map of “ Some modern philosophers” “think [something] just might” [something] is an incoherent patchwork.

I think that theorizing about things without hard evidence has value. What-if’s teach us a lot, by raising important questions, and keep our ideas flexible, preparing us for the next crazy insight that nature reveals.

But that isn’t the same as attributing any reliability to the as yet unproven enthusiasms of philosophers.

There is a clear case for a survival benefit for creatures whose awareness and control extends into their own thinking. Thus a reason consciousness would be one of many strategies evolution may produce.

What natural phenomena is explained by a conscious rock hypothesis? What would cause a rock to organize in such a way? Where is this information about itself encoded and experienced in a rock? It’s not a coherent conjecture.


It is incoherent because it lacks evidence, not because the idea is absurd.

My computer is made from rocks.


Natural formation rock consciousness both lacks evidence and is absurd, as there isn’t even a coherent reason to think it might or could.

Your computer processes information, and can be configured to process information about itself. At least the possibility and potential utility exists that conscious computers may one day exist.


Humans are a natural formatiom. The laws of science are our only real limit here so let's be honest about this.


That is a breathtakingly pedantic reading of what I said.

I used “natural” to distinguish minerals created via geologic processes, from minerals and elements intentionally processed into machines.

Similarly, evolution’s long process of accumulated innovations separate humans from our constituent elements as found in the geologic environment.

Both technological and evolutionary iterative and self-reinforcing adaptations provide a mechanism for complex coordinated high level information flows to arise aimed at survival (biological or economic) where consciousness has both a potential purpose and a plausible process for coming into being.

A lump of granite or obsidian presents no evidence of consciousness, no purpose for consciousness, and no plausible process for having accreted or transformed into something with consciousness.

The conjecture that such rocks may be conscious stands on equal footing to the conjecture that they are unicorns wearing magical rock-disguise cloaks.


> The conjecture that such rocks may be conscious stands on equal footing to the conjecture that they are unicorns wearing magical rock-disguise cloaks.

Hah! I would love to prove you wrong by imagining the perfect geological formation (many rocks as humans have many complex organs) that can receive and transmit coherent, dense information,

but I am a mere mortal.

For all practical purposes you're right, and for all philosophical purposes The Thinking Rock is an extreme example.

Let's revisit this thread in 5000 years after humans have gone interstellar and see if we can't review some evidence of unconventional life forms.


> Let's revisit this thread in 5000 years after humans have gone interstellar and see if we can't review some evidence of unconventional life forms.

That would be wonderful!

I have no doubt that different chemical foundations, and different environments will yield extreme differences in morphology.

The uncountable differences between humans and the octopus are a vivid example of how little aliens may resemble us.

It would be most interesting to know if life could evolve in oceans under planetary crusts, sunless rogue planets warmed by radioactive decay, in the extreme conditions around magnetars where chemistry takes on different rules, in thick rings or atmospheres around gas giants, or in methane or other non-water “oceans”.

Surely somewhere there are energy conserving hibernating “rocks” that we might be well surprised to discover are sentient!


> t's not impossible that even an LLM, which totally isn't designed with the goal of having it, might nevertheless have it.

I was referring to the idea that a brain scan of a human could be copied into an LLM.


Oh, in that case I agree. My understanding is LLMs (or at least GPT-architectures) aren't Turing machines, so they can't simulate arbitrary other systems even if you made them very big, and because of this my guess is that it would be extraordinarily unlikely for them to just happen to have the right shape and power for simulating a full human brain.


I think OP means how do we know that the brain tissue that is being used in the experiment is not conscious.

Here is a man that lived a normal life with 90% of his brain damaged, a large portion of that just completely missing.

https://www.sciencealert.com/a-man-who-lives-without-90-of-h...


Sneaky paragraph at the bottom:

> Update 3 Jan 2017: This man has a specific type of hydrocephalus known as chronic non-communicating hydrocephalus, which is where fluid slowly builds up in the brain. Rather than 90 percent of this man's brain being missing, it's more likely that it's simply been compressed into the thin layer you can see in the images above. We've corrected the story to reflect this.


I did not see that actually, thank you.

The fact our brain can be compressed to that level is pretty crazy too, although not as impressive as the original missing 90% :)


You're welcome :)

I very nearly missed it on that page, despite already being aware of the detail from other sources.


Network pruning.

In ANNs, pruning 90% of the weights without substantial loss isn't unheard of. I guess this may be analogous: continuous pruning and fine tuning over a lifetime. Though, is removing 90% of the brain more analogous to 90% of weights, or 90% of the rank?


At this point it feels like we’d required the resources of an entire planet to run a single full-fidelity virtual brain. Which leads to interesting science fiction premises.


Or one entire actual brain - if it can be done once by natural selection, it can be done more efficiently again by a designer.

Time exists because the universe doesn't do calculations - the only way to see the outcome is to do the thing. See: The Three Body Problem



Last I heard (I am not a brain scientist) we don't really know what fidelity we would need.

https://en.wikipedia.org/wiki/Mind_uploading#/media/File:Who...


Likely relevant to source of the living brain tissue:

“Brain biopsies on 'vulnerable' patients at Mount Sinai set off alarm bells at FDA, documents show” https://www.cea.fr/english/Pages/News/world-premiere-living-...


A millimeter cube seems large when it comes to a 9 month… Let alone 3…

This seems weird that they got this much LIVING brain tissue…


Resective surgery is the most common epilepsy surgery. It involves the removal of a small portion of the brain. The surgeon cuts out brain tissue from the area of the brain where seizures occur. This is usually the site of a tumor, brain injury or malformation

https://www.mayoclinic.org/tests-procedures/epilepsy-surgery...


Small mammals up to the size of hamsters can successfully be cryogenically frozen and revived significantly later. So while the same thing working on small samples of human tissue is completely expected it’s still useful research for organ transplants etc.

All that cryogenic preservation that showed in science fiction is somewhat realistic even if we can’t do it yet and it’s probably going to require extensive surgery beforehand to enable rapid cooling.


> Small mammals up to the size of hamsters can successfully be cryogenically frozen and revived significantly later.

Reference?


https://doi.org/10.1098/rspb.1956.0054

(Yes, it's the same James Lovelock.)


That reads more like surviving extreme hypothermia than being frozen and thawed in the sense of cryogenic preservation. The greater the percentage of water in their body that was frozen, the less likely they were to survive, with some precipitous cliffs around 50% and 75%. Am I misreading it?


Thanks. (Those poor hamsters!)


> a little less appealing than the clickbait title

I read that as "appalling" and ... it's kind of both.


I thought brain cells didn’t reproduce.


A few years ago I became interested in the cryonics movement.

What I find most interesting about it aren't the kooks and weirdos that are into cryonics, but the visceral reaction that your average Joe has to the idea.

The average opinion about cryonics seems to range from 'That is impossible' to 'why would you want that?'. But if you ask that same average Joe about a cure for cancer they're likely to say that it's been done and the rich just horde it for themselves.

It's weird that they don't see things like cures for cancer, regrowing organs, age slowing drugs etc... as all part of a pathway to the same thing which is a technological solution to many causes of aging and death.

Unlocking the ability to grow and store organs or even just store donated organs cryogenically is highly desirable from an economic standpoint has it frees up so many resources (1pc of US GDP is spent on dialysis alone) so if there's a technological means to do it we're going to find a way sooner or later.

And once we've found a way to freeze and revive large parts of the body it's just a gruesome divide and conquer from there...


By my calculations 0.078% of GDP is spent on dialysis. Still crazy looking at the raw numbers.

$20billion/$25.4trillion

https://tradingeconomics.com/united-states/gdp

https://www.propublica.org/article/in-dialysis-life-saving-c...


Reminds me about an article on ECMO machines I read where they are researching hooking them up to single organs and not just people. If you can keep the organ alive for some time it opens the possibility of making transplants easier, or even removing someone's diseased liver, say and treating it outside the body then putting it back a few weeks later.



I did read an interesting thing recently (can't remember where unfortunately) about ongoing strides in the transport and preservation of donor organs. If we crack the code to putting a kidney in ice, you can get it across the country to its new owner instead of crossing your fingers that someone local needs one and is a recipient match.


> a technological solution to many causes of aging and death.

I wouldn't count the cryonic freezing of a perfectly good brain (aka immediate brain death) among those, at least until there's a convincing solution to the teletransportation paradox.


Imagine a backlog of frozen people who can now be unfrozen due to the availability of a cure, but who now have to reintegrate into society. The political implications would parallel the controversy introducing refugees


https://readcomiconline.li/Comic/Transmetropolitan/Issue-8?i...

Enjoy.

This comic series and specifically this issue is what made me fascinated about cryonics as a teen.


imagine a life where a contract between you and a soulless corporation or religious order forbids you from dying, and no matter how many times you try to escape, they bring you back for untold miseries.


You must watch the movie Moon (2009). I strongly recommend. See https://m.imdb.com/title/tt1182345/


Read "We are legion. We are Bob." It includes that plot.

There is alao the bit about a revived cryo-guy being a computer program running an exterminator company. Then he decides most teenagers at the mall need to be exterminated.


That wasn't a religious order forbidding him from dying, that was rot13 n eryvtvbhf beqre gung jnf va na nezf enpr jvgu bgure pbhagevrf gung gbbx gurve bja nccebnpu gb NV naq whfg svtherq gur cebgntbavfg'f oenva jnf n tbbq fubegphg.


Your favorite sci-fi plot is not a realistic prediction of the future.


sci-fi is not about the future, it is a commentary on the present.


"We need you for long term maintenance of our mainframe's COBOL code base; in return we pay you very well, but when we say long-term, we really mean it."


Essentially a Ghola in the dune universe


Read those EULA's!


Imagine living happy, fulfilling endless life.


I mean, sounds like a skill issue to me


Freezing and thawing organoids is not new, it’s fairly routine. The frozen piece of brain from an epilepsy patient doesn’t retain ”normal function”. There is no evidence in the paper that it integrates into neuronal circuits (this was not even tested), or supports anything like normal neuronal firing. The cells are alive, yes, and likely highly abnormally perturbed.


I just imagined dying and then noticing myself thinking again but without any sensory inputs; freaky stuff.


I recommend you google sleep paralysis. I experienced it a couple of times when I was younger. Really scary.


This was super freaky before one could read about it on the internet, I remember it happening to me in the 1970-1980s and thinking it was something really wrong with me or supernatural in nature at the time, which as another commenter notes was what people in medieval times thought. It was such a relief to read that other people had similar experiences by 1990s.


I remember that when I was around 8 or so, it happened several times in the morning while waking up, that I saw someone entering the bedroom while I was not able to speak or move. It was terrifying. It must have been imagination, since nobody appeared to have noticed anything unusual.

Is there a name for such event?


There are (creepy) reports from the middle ages of figures sitting on sleepers' chests, legs, moving towards them etc.

It's clearly a biological phenomenon of some description. I've never really looked into it, despite experiencing it often. Related my general take on it below.


These are common symptoms of sleep paralysis - https://en.wikipedia.org/wiki/Sleep_paralysis


If you get this often, I've noticed it's tied to sleeping position. I'm often at an angle where I'm getting poor oxygenation, sorta like sleep apnea.

For me this is on my back with no pillow (angle of neck/throat) but I'm fine on my side or stomach.


Sleep paralysis is consciousness when you are supposed to be knocked out, AFAIK unrelated to oxygen levels. There is possibly a correlation to sleep apnea but I think that is more likely due to hEDS being a common cause for both. hEDS not rare, it is pretty common, far more than doctors think. People with hEDS have very weird drug interactions, many often have a genetic resistance to local and general anesthesia. I think a reasonable explanation is they are also resistant to whatever the chemical the brain uses that causes sleep induced loss of consciousness to the point they are more prone to sleep paralysis.

The N of 1 with changing positions is interesting though.


> I think a reasonable explanation is they are also resistant to whatever the chemical the brain uses that causes sleep induced loss of consciousness to the point they are more prone to sleep paralysis.

I cant rule out your explanation, but I personally in favor of another one. It is not a supression of consciousness doesn't work, it is the clearing blood from whatever the chemical that stops propagating signals to muscles. When everything works good you are relieved of paralisys at the same time your consciousness wakes up. I never experienced sleep paralisys, but when I wake up suddenly and try to move instantly I can sometime feel a fleeting sensation of it. I never gave it a second thought before I learned about sleep paralysis.


I can consistently give myself sleep paralysis in that position 90% of the time. I am tall, but I don't have any symptoms of hEDS. They'll figure it out someday. I thought more people got sleep paralysis, and just never clued it to it being a certain position (which I believe pinches the neck in a certain angle).


It may be linked to a sleeping position, but I'd bet not on poor oxigenation, but on obstructed blood stream that makes it hard to spread that chemical that turns sleep paralysis off.

I do not remember details of phisiology of sleep paralysis, what is the paralysing chemical, and which one is stopping it, and where from they come, but it seems plausible that sometimes a sleeping position can make it hard for chemicals to reach muscles and free them from paralysis.


I had it once and it was the most terrifying experience of my life.


I have had similar experiences a few times. One time it was extremely scary. I could not move, and I experienced someone whispering something unintelligible in my ear.


Can you guys elaborate? Do you feel like you’re some brain in a vat somewhere when this happens?


This has happened often enough to me that I am sometimes now aware of it when it's happening, occasionally, and can ride it out. I've literally "invited" more terror to try to end it quicker before. As in, "yeah yeah , get it over with, bring it on". I haven't questioned the normality of this until now, amusingly.

It normally happens when I sleep on my back. I have been known to make an attempt at a scream during the event. I'm normally being attacked at speed, by people or things that don't really have boundaries. And of course I can't fight back, hence the paralysis.

For the scream, I think I have heard it, but because of the paralysis it ends up like a loud exhale with some high notes in it. I couldn't describe it as a roar. More of a pitiful gurgle.

It is sometimes made worse by my sleeping partner trying to wake me clumsily, which momentarily heightens the terror, especially if my face is being nudged or jabs to the ribs.

So not particularly fun, literally facing my demons, but also probably some of the best VR you're likely to experience.

For background, I'm a generally positive and optimistic person, rational with zero belief in the supernatural, despite being raised with it. Oh god I'm cursed... I kid, but who knows from where these intrusive dreams originate. I do practice martial arts, but this predates that. I have had an interest in light combat since childhood, despite pacifism and fear being more of a reflection of my personality. It was probably more of an 80s thing, expecting violence and quicksand at any moment.

That's about it really, totally normal to me at this point. It's probably nothing.

EDIT: For the record, it feels like the paralysis triggers the dream, not the dream triggering the paralysis. Something to do with approaching a waking state in the brain but not the body. Cue the terror and internal screams for help.


Wow, on wikipedia I read that 5 percent of people experience it regularly. Hopefully you get better at 'fighting your demons' while getting to know them better.


I could see but I couldn’t move any muscles. It felt like five minutes but was probably less. It happened in an afternoon nap which is something I never did.

I was screaming internally for my girlfriend to notice me. I thought I was suddenly a quadriplegic or something and was panicking. Eventually my girlfriend noticed (she later said she noticed my deep, heavy breathing) and shook me and being shaken pulled me immediately out of it.


This is almost exactly how it is for me as well. I've experienced this 50+ times, the feeling of complete or almost complete paralysis. I make a great effort to move and can feel my heart racing and heat in my face from panic and exertion. I can see my immediate surroundings; if the sun is up I can tell it's daytime. Although my eyes are open and aware, I'm not quite fully alert. Sometimes there are hints of hallucinations like the feeling that a shadowy figure is approaching my bed, and it's scary, but most often I'm just aware that I'm paralyzed. As a child I learned that if I can force a limb to move slowly, I will usually jerk myself fully awake. About 25% of the time I can calm myself down and fall back to sleep.


> I could see

How do you know that you weren't simply dreaming?


REM atonia, which is the paralysis that sleep paralysis comes from/uses, paralyzes the majority of your body. However, one organ it doesn’t paralyze is your eyes, hence people experiencing it generally open their eyes as they try to escape it. However, even with your eyes open, you can experience dream-like hallucinations overlayed ontop your view of reality, hence people thinking they see other entities in their bedrooms, etc. It’s possible that it was a dream, but it’s completely possible it wasn’t, so if a person claims they were awake, then in all likelyhood they were.


Well, there's an objective test: did they see something that actually happened out in the world during the episode that could be verified later?


When it happened the Monorail episode of the Simpsons was on. And it continued to be on when I was shaken out of it because my girlfriend suggested we just watch the rest to get my mind off it.

It was also just a very vivid experience. I felt completely awake. Just unable to do a thing.


Thanks.


Some people feel some kind of person/presence close to them, that's how it happened to me. This [1] weirdly makes sense.

It felt kind of like those dreams where you can't move. Except you've woken up, I could see the correct room and position I was in. It tends to come with fear and doesn't last long.

Never happened when I slept on my side or front. I almost never sleep on my back now. Also, chronic stress could have been a trigger.

[1] https://commons.wikimedia.org/wiki/File:Henry_Fuseli_(1741–1...


First time it hit me I was like "am I dead?" creepy stuff, subsequent times are more annoying than scary.


Gives me hope we can reverse the damage wrought by Js and return to Lisp


Next is to freeze and unfreeze someone for a couple weeks and see if they are still the same person. If this works everyone and their mothers will want to be forwarded a few hundred years


If you're very rich you could probably forward yourself now by building a very fast spaceship and flying out for a while and come back a decade or two into the future.


It said "Just five more minutes, Mom" and went back to sleep.


Interfering with the pathway that causes cell death is very interesting. Maybe more than freezing.

Related sci-fi: https://galactanet.com/oneoff/antihypoxiant.html


Big news for Ted Williams



Cryo me up, Scotty.


So is Walt Disney coming back?




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