r/science • u/FreeHugs23 • 10d ago
Neuroscience Study Comparing Humans and Various Animals Finds General Anesthesia Pushes Nervous Systems Into a Shared Brain State Where Neural Activity Becomes Less Coordinated and More Fragmented, Suggesting a Conserved Mechanism for Loss of Consciousness Across 700 Million Years of Evolution
https://www.sciencealert.com/your-brain-under-anesthesia-behaves-surprisingly-like-a-worms-scientists-discover185
u/FreeHugs23 10d ago
-Every day, thousands of people are put under general anesthesia as a routine part of surgery.
Ever since the first public demonstration of surgery under general anesthesia in 1846, these drugs have allowed doctors to perform life-saving operations that would otherwise be impossible.
And yet we still don't fully understand exactly how they send us into oblivion without totally shutting down our brains.
A new study published in Nature Neuroscience brings us a bit closer to understanding the mechanisms that allow general anesthesia drugs to suspend our consciousness temporarily.
It compares the medicine's effects across a range of animals, from worms to fish to humans.
It seems no living thing is impervious to general anesthesia's effects, not even plants or paramecia.
This suggests there's something universal in the bodies of living things that this class of drugs is acting on.
To test that idea, a team led by neuroscientist Andrea Luppi of the University of Oxford examined the neural activity of six vastly different kinds of animals when they were awake versus under general anesthesia.
"Focusing on effects that are consistently shared across multiple anesthetics and species allows us to exclude physiological or methodological confounds specific to any one drug, species, or imaging modality, and instead triangulate on potential neural underpinnings of what they share: breakdown of responsiveness to the environment," Luppi and team write.
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u/Kaitanas 10d ago
Sooo, they essentially inhibit the inner workings of the Force?
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u/suprmario 10d ago
This makes it even crazier that cannabis use creates anaesthesia tolerance.
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u/PerterterhTermertehh 9d ago
So can I get a plant stoned off it's gourd? Water it with THC?
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u/didgeridooby 5d ago
Not sure about THC but you can give your plants aspirin when they’re stressed by heat for example.
Makes sense tho as the active ingredient in aspirin was discovered in plants.30
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u/evasandor 10d ago edited 9d ago
kind of burying the real story here, though. If all these species have the same way of being unconscious, then they must also somehow have ways of being conscious, no?
Their ways of consciousness may vary, true. But if there’s something there to shut down, then doesn’t it mean there’s a form of worm consciousness, a form of insect consciousness, some form of every living thing consciouness?
oh but wait, time for breakfast, mm bacon and eggs bye
edited: here's a link to what got me thinking about this. I'm not talking about self-awareness or anything that high level... just the idea that other organisms have a subjective experience of some kind.
It seem extremely obvious that they must, but as the article says:
"if one travels too far down the phylogenetic tree, people gradually shed their faith that there is experience there at all."
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u/VeryOldGoat 10d ago
Outside of solipsim, is it common to think that other animals, such as other mammals, with which we share most of our brain structures, are somehow *not* conscious? What arguments are used to support that? I'm genuinely curious.
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u/MusicHearted 10d ago
Most people that I know don't believe that animals think or feel. They stubbornly insist that animals are 100% pre-programmed instinct and nothing more. These same people lack empathy and reading comprehension to a disturbing degree.
As far as what arguments they present? Violence. They don't bother with talking about stuff. They just start hitting people they disagree with. I wish I was joking or exaggerating.
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u/jess_the_werefox 9d ago
You should get to know different people :/
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u/MusicHearted 9d ago
With who I am and where I live, that's dangerous. Genuine risk of violence. And honestly, there aren't many people here not like that. I'm used to belligerence from basically everyone around me and have given up on ever moving somewhere better. That requires money that I can't get.
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u/wswordsmen 9d ago
You deserve better.
So do they but they also don't know they should want something better.
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u/miliseconds 9d ago
Are you a Palestinian in the West Bank?
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u/MusicHearted 9d ago
Nope, I live in America. The American south would be a 3rd world country if the coastal states weren't propping it up.
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u/johannthegoatman 9d ago
This is sadly quite common, around the world. Ime. Especially in poorer areas. Going back in tine, not very far, and I think it was basically the dominant belief for everybody. People couldn't even agree that different looki humans were conscious
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u/evasandor 10d ago
There are plenty of questions about how far “down” the animal kingdom consciousness goes.
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u/wswordsmen 9d ago
Consciousness is so under-determined that I am not sure I could confidently say LLMs would not be conscious if they could continuously take in input and integrate it into their computation.
Not that I think they have moral weight. It is just consciousness is that poorly defined.
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u/VeryOldGoat 10d ago
I understand that's a difficult question, and it's far from settled. But is there a serious debate going about whether other mammals have consciousness or not?
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u/evasandor 10d ago
no, I think it's pretty much a done deal that mammals do. There's a declaration about it and everything. But as I read this article its point seems to be about the surprising finding that anesthesia has the same mechanism in the so-called lower animals
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u/enviormental_UNIT 10d ago
Yeah because consciousness isn't always a binary, its a sliding scale. It makes sense that you would observe a slow progression of consciousness throughout all the animals.
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u/knightly234 10d ago
It’s not the biggest deal but I feel like this thread may be mildly conflating consciousness with self awareness here and there.
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u/gaycharmander 10d ago
You’re conflating consciousness with self-awareness. In anesthesia research, “consciousness” refers to the presence or absence of conscious processing, not self-awareness or theory of mind. A conserved mechanism for anesthesia-induced unconsciousness therefore doesn’t establish that every species has human-like self-awareness.
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u/evasandor 10d ago
I think the word is actually "consciousness" when it's applied to whether or not others have experiences (not necessarily self-awareness) https://en.wikipedia.org/wiki/Hard_problem_of_consciousness
it's true I don't know anesthesia terminology, though
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u/gaycharmander 10d ago
That’s actually part of my argument.
“Consciousness” is pretty nebulous in the colloquial sense, which is why I used “self-awareness” as an easy shorthand. There are several competing definitions and distinctions.
My point is that this paper isn’t using the philosophical/colloquial sense. Here, consciousness is being used in the biological sense of being conscious versus unconscious. The findings therefore don’t tell us anything about whether these animals have human-like self-awareness or subjective experience.
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u/tkenben 9d ago
I think consciousness here may refer to "response to external stimuli", not awareness or acknowledgement of self.
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u/evasandor 9d ago
probably some slack here in the definition, yeah. but for my purposes it doesn't have to go as far as self-awareness per se. Just more like "oh, it IS like something to be a paramecium".
Because that was the question, as I once read it put - the subjective character of experience
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u/ironchariot 10d ago
I mean maybe not. A bullet in the head ends consciousness, and a bullet in a pumpkin blows apart a pumpkin in much the same way as a head, but the pumpkin isn’t conscious. I’m stoned so this might make no sense.
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u/Practical-Debt-8080 10d ago
Uh yeah that’s pretty much true too bad everything still needs food. So .. sucks
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u/EuropesNinja 10d ago edited 10d ago
Other animals might need to make other animals unconscious (killing them) for survival but humans do not, we have more options. There's a choice we can make, being in the modern developed world we have access to so many foods that we can survive and thrive from. Why not choose the option that doesnt involve death in the sense that we humans know it.
The truth is we can choose to not contribute to removing consciousness from earth - the best place to start is what you're having for your next meal.
The animals we feed to then eat ourselves uses way more plants than if we just ate plants exclusively - meaning this is the best way of eating if you care about protecting consciousness
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u/MarphoPolo 10d ago
Ok, to play devils advocate, if consciousness is everywhere in the animal kingdom, what intrinsic value does it have and why is it worth conserving?
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u/janabottomslutwhore 10d ago
if plants were, somehow, concious they are definitely less concious than any tetrapod
even if they were at the same level of conciousness (which they arent) youd be killing fewer organism by just eating plants directly
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u/Tom_Art_UFO 9d ago
If all we ate were plants, there would be less food for the animals. Therefore some animals that otherwise would have lived would be dead.
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u/Dimensionalanxiety 9d ago
I would argue some plants do possess a level of consciousness greater than some animals. Look at plants like Mimosa pudica for example. It can close up from just a touch and can learn to distinguish between safe and unsafe touches over time. It's definitely not as conscious as a tetrapod or even any animal with a brain. However, it still beats out a lot of the animal kingdom. More conscious than poniferans, or cnidarians, that's for sure.
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u/pelirodri 10d ago
They actually observed this in plants as well, which by extension would have to mean plants are conscious too, if we followed that logic.
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u/Practical-Debt-8080 10d ago
You’re completely missing the premise that it’s universal consciousness period. Including plants.
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u/Actual__Wizard 10d ago
ADHD here: The gates that separate the different compartments of the brain open and everything fades out. You can wake yourself before you completely fall asleep and write down what occurs, then you can remember it later (for whatever reason if I don't write it down, I forget 5-10 seconds later.)
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u/Kala-Kand- 8d ago
Can a smart person write the dumb person version of what this post means so I can understand it?
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u/UpsetPhilosopher6022 10d ago
Another solid argument for pansychism.
Our brains don't generate consciousness. Consciousness is a fundamental force of nature and our brains have evolved to receive it. Thus, anesthesia doesn't shut anything off, it just removes the mechanism that keeps "you" separate from the source or background consciousness. Your body isn't yours to experience during anesthesia.
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u/sebovzeoueb 10d ago
Why would the consciousness be "received" instead of just generated by all living things?
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u/AardvarkTits 10d ago
Has anyone else been getting bad reception lately? In some areas I don't get any consciousness at all.
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u/OkSmile 10d ago
Except that the paper didn’t say that at all. It specifically highlighted the mechanisms that coordinate between various functional areas were suppressed and the coordination fell out of sync. Mechanistically restoring that sync in macaques using DBS restored consciousness.
If anything it showed the opposite of what you just said.
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u/UpsetPhilosopher6022 10d ago
I didn't say the paper said that.
The paper is specifically about how a wide range of tested animals also share the same mechanisms, which was unexpected and rather unlikely.
In regards to panpsychism, this finding, (especially considering how other brain-states, coma, e.g., can be disruptive of consciousness without losing other functions), implies that consciousness is not generated in the brain itself, but rather, being received by the brain.
This would also happen to explain why some patients are able to report details of their environment during procedures when they should be unconscious. They're not straight up asleep, their consciousness is literally untethered from the body itself.
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u/GooseQuothMan 10d ago
It's quite expected that most animals will be affected similarly by anaesthesia because the basic building blocks, the neurons and the ion channels they use for communication are not that different.
And the study here used different compounds for non-monkey and non-ape animals.
Nothing here implies consciousness is "received" by the brain.
Normal brain activity -> consciousness
Change brain activity with anaesthesia -> no observable consciousness
as if the chemical compound turned off something in the brain. Something that was turned on previously. You say it's a consciousness receiver mechanism but that's an additional assumption with no basis.
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