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How far neuroscience is from understanding brains (2023)

101 points by Gooblebrai 2y ago

deleted 2y ago
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curtisszmania 2y ago
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bena 2y ago
I would think a large part of the problem is the difficulty in observing a working brain. There are very few non-destructive ways we can get a look into a brain while it is living. And even research into ways we can look into a living brain is hindered by the fact we don't want to harm the person being observed. I could see that making progress a lot slower
- jampekka 2y ago
  > And even research into ways we can look into a living brain is hindered by the fact we don't want to harm the person being observed. Animal brains are harmed for research all the time. Some species, like Zebrafish can be even imaged real-time at neuronal level. As the article says, the problem is really that there are no good foundational ideas of what are the basic operating principles of the brain.
  - bena 2y ago
    I did mention people specifically. Mammalian brains are fairly more complex than piscine brains. People are important because we can't tell a fish to perform an action or to think of an elephant, etc. So while we can image, we can't know what correlates with a high degree of certainty. But even in other cases, a working brain is an entirely different object than a non-working one. Finding those foundational ideas and basic operating principles because we can't test a living brain. It's almost chicken/egg. Being able to experiment on a living human brain would probably give us much better ideas of the basic operating principles. And once we know those principles, we could probably move from experimenting on living human brains. Like, we can dick around with muscle. We can force it to perform as it were living and receiving signals. And that's partly because you can cut open a living person and watch those muscles operate. You can manipulate those muscles in a living person. You can measure things, etc. It's much harder to do that with a brain. Because it's incredibly easy to make irredeemable mistakes.
    - glenstein 2y ago
      >So while we can image, we can't know what correlates with a high degree of certainty. I don't think I agree just on this piece, though you are making important points here. We can know, for instance, of visual or spacial awareness, reactions to certain stimuli or objects introduced in their environment, and so on. You're not wrong on the importance of learning from active brain functions but I think we can at least make meaningful inroads with animals. > Finding those foundational ideas and basic operating principles I know a lot of people talk this way about brains and consciousness, that we need to first have our definitional elements before we proceed with research. But I think we often have, as the object of research, closing in on those elements, while gathering all kinds of functional and theoretical data from the mass of complicated noise that is brain structure and activity. We can build out correlations, mechanisms, and so on and close in on foundational elements. It may even be the case that foundational organizing principles turn our understanding inside out in important ways, but I have never understood the idea that we are stuck if we can't start with such things in hand.
      - bena 2y ago
        I'm sorry, I see where I wasn't clear. I'm talking about very specific correlation. Like when I type these words, exactly how and what fires to achieve that. Which neurons and pathways are the thought "hit these keys", what's the signal to the fingers etc. We know "When this area is active, this group of actions can happen". It's hard to get good resolution. And I believe it would be easier to replicate consciousness if we knew how it worked, I also believe it's possible we eventually figure it out. It will just be much harder. And we may not know when we do it either. I believe that is where we will need common, agreed upon definitions. But defining intelligence and consciousness is difficult because you have to define it in a way that includes everything we agree is conscious and excludes everything we agree is not. And we'll also have to agree what is and is not conscious. It's a way more involved problem than a lot of people give credit.
        glenstein 2y ago
        >But defining intelligence and consciousness is difficult because you have to define it in a way that includes everything we agree is conscious and excludes everything we agree is not. I think this is extremely important, but I would say that methodologically, messy definitions can nevertheless be stepping stones that bring us closer to full comprehension of definitions. I suppose I just have a specific hobby horse in this context and I don't know that I'm responding to you so much as a general idea I've seen elsewhere, that you're rhyming with, which is this idea that research has to start from agreed upon definitions. I would say instead that there are such things as characteristic instances that embody lots of the stuff we are interested in, such that we can say "whatever consciousness is, it involves that" and we can just point to something that's a wild, underdefined phenomenon, and make it subject of study. Without a definition, I can still understand that states of mind that involve, say, wakeful awareness and intention are going to be about consciousness. We can know necessary conditions even if we don't know "sufficient" conditions, and the former are a stepping stone to comprehending the latter.
- mbauman 2y ago
  The even bigger challenge is determining _what_ you need to observe in the first place. As a simplistic analogy, evolutionary designs of FPGA boards can end up relying upon idiosyncratic properties of the board(s) and create circuits that "shouldn't work" based on an idealized electrical circuit model. And they may not be transferable to other boards. In other words, to "understand" some evolutionary FPGA circuits, you need to "observe" more than just the gate configurations and idealized schematic. Brains are not FPGAs or even circuits, but I think the analogy holds. They're not _just_ idealized representations of spiking neural networks.
  - NoxiousPluK 2y ago
    I remember reading an article about this years ago - a non-transferable FPGA configuration which had some logic that should be unreachable but didn't work without it. Very faschinating but I've not been able to find it since.
    - nick__m 2y ago
      I think you want that paper "An Evolved Circuit, Intrinsic in Silicon, Entwined with Physics" available there https://cgi.cse.unsw.edu.au/~cs4601/refs/papers/es97thompson.pdf https://cgi.cse.unsw.edu.au/~cs4601/refs/papers/es97thompson...
- tim333 2y ago
  I agree and think the way forward is computer simulation. Figure out a simulation equivalent of a neuron and put a lot together and see how well the simulated brain portion matches the real thing. That hasn't really been possible due to lack capability of computer power but we are getting to where it could be. They have of course done stuff with "artificial neural networks" of the ChatGPT type but those are very far from biology. DeepMind has been doing work along those lines with 'AI BRAIN' https://medium.com/@daneallist/unlocks-secrets-of-real-brains-google-deepmind-ai-brain-5f51214b3d35 https://medium.com/@daneallist/unlocks-secrets-of-real-brain...
  - renewedrebecca 2y ago
    How do you simulate something you don't understand? The basic problem here is that we don't understand what a neuron does, so how would we model it?
    - deleted 2y ago
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    - KineticLensman 2y ago
      > The basic problem here is that we don't understand what a neuron does, so how would we model it? We understand lots of aspects of neurons and can model those. See the wikipedia page for some examples of well-understood principles.
      - tim333 2y ago
        Yeah and you can do a simulation using a rough approximation and then it is interesting to see in what ways it matches real brains and in what it does not. It seems the DeepMind rat brain didn't really try to get close to biological neurons but still produced outputs close to a real brain. (vid from here for about 2 mins https://youtu.be/hIuXXvWY6-4?t=125 https://youtu.be/hIuXXvWY6-4?t=125)
    - deleted 2y ago
      [deleted]
- seejayjordan 2y ago
  Look up Wada Test, where we shut down each hemisphere (one at a time) of the brain, while the patient is awake, to see how their personality changes without 1/2 their brain. Also stereo EEG. 200+ sensors placed in/on/around the brain, patient stays in bed for a week measuring brain activity. Here's the kicker... neurologists can plug into the brain and send teeny bits of electricity to each of the 200+ sensors individually to see what happens (typically this is for identifying seizure spots). Wish I didn't have to know this, but my partner is very epileptic, and has an RNS device implanted in her head. We upload her brain activity daily!
  - Gooblebrai 2y ago
    According to Wikipedia the personality barely changes and the tests is mainly done to detect which side is on charge of language and memory
imchillyb 2y ago
We are just now uncovering an underlying principle of science: ‘everything is a wave.’ Neurological connective tissues and their corresponding signals may be more of a symptom of electrical wave action rather than a signaling nexus. Everything is a wave. Everything is a probabilistic wave form with probabilistic outcomes. Once science understands these waves and their myriad forms, we may have a greater understanding of our own wires and grey matter signaling.
- guappa 2y ago
  We understand gravity and the 3 body problem still exists…
  - 0x1ceb00da 2y ago
    We just don't have a general solution of the 3 body problem in the form of equations. Practically speaking it's a solved problem because we can simulate the motion. We could do the same with brain. That's basically what neural networks are.
    - willy_k 2y ago
      We can simulate the three body problem because all of the significant parts of the problem can be known. This is FAR from the case when it comes to the brain.
    - goatlover 2y ago
      Neural networks are not simulations of neurons.
    - Gooblebrai 2y ago
      Can we simulate it indefinitely? I thought chaotic behaviour entered the game at some point.
prismatix 2y ago
If you find this interesting, the Theories of Everything podcast with Curt Jaimungal does a good job exploring this topic. The neuroscience-centered conversations focus mostly on consciousness, but they still discuss similar problems with measuring and explaining how consciousness comes about from a collection of matter.
intrasight 2y ago
I took a break from artificial networks to study neuroscience for a couple years. We hardly understand how a single synapse works - and we have trillions of them.
- minihat 2y ago
  This is exactly right. I started a PhD in 2017 studying neuroscience + ML. I thought studying the brain would help me understand ANNs better. I was wrong. Ended up applying ML to analyzing EEG, MRI and similar.
  - bumby 2y ago
    Is this because we're misapplying the analogy to ML? I.e., in an effort to communicate and understand ANNs, we "pretend" it's like a brain. Just like before, we used "file retrieval systems" to understand the brain, or electricity is like "water in a pipe", which are also wrong. Analogies often only go so far, beyond which they do more harm than good.
    - beezlebroxxxxxx 2y ago
      What you're describing is endemic across HN (and tech, tbh). Lots of people on here "know" computers/programming/CS very well. They, naturally, tend to use analogies to computers/programming/CS when trying to explain or "think out loud" in their comments. That's fine. It's what they know. The common problem arises when people forget they're analogizing and begin to see their analogy as ontologically and conceptually identical to the thing they were making an analogy for. This requires a certain amount of ego, echo chambers, and self-valorization, so that they never have to face the actual issues with these analogies. But as many comments here have pointed out, studying neuroscience, for example, usually makes those analogies seem painfully inadequate. The same is true in philosophy of mind, for example.
    - SkyBelow 2y ago
      Have we hit the limit of the analogy, or have we hit a limit in our understanding? Both neural networks and actual brains have behaviors that emerge from the interactions of smaller components. Neural networks have trivial connections compared to brains, but our understanding of the emergent behaviors seems very limited. To me, this is a sign not that the analogy has reached a point of breaking down, but that our tools aren't sufficient to work on even then trivial connections. I do expect the analogy will break at some point, but I'm not sure we have reached that point yet.
teqsun 2y ago
This is the main reason why I have skepticism towards any claims of imminent AGI.
- mellosouls 2y ago
  I'm also sceptical but to be fair, we don't need to understand how the brain works for AGI, that's just one (obvious) path.
  - JackFr 2y ago
    Who knows? Maybe it’ll turn out like flying and birds. Studying birds gave us some data, but mimicking them wasn’t what got us jumbo jets.
    - southernplaces7 2y ago
      Sort of a shame... I always wanted to fly in an ornithopter.
  - southernplaces7 2y ago
    Since we don't yet have anything remotely like AGI and at the same time, don't even really know how the brain works or what consciousness is aside from being aware that we feel it, you and nobody else really know if our path to consciousness is just one of many. For all we know it might be the only one. There could be some very big unknown unknowns in those waters.
    - glenstein 2y ago
      I would say I think those are all pretty good observations, all perfectly true and I think AGI is more plausible than it's ever been in light of what we've demonstrated via LLMs. Our understanding really is that limited but I don't take it to be a counterpoint to the prospect of AGI.
    - Traubenfuchs 2y ago
      > what consciousness is Probably an unavoidable property that emerges from the sheer and perverse complexity of the human brain, its 100 billion connections and the unimaginable amount of interactions between them, modulated by neurotransmitters + their reuptake, length, amount, location, quality and condition of pre/post-synaptic receptors, axons and other nano structures in the brain... Comparing this disgusting moist, fleshy and electric masterpiece of nature with something primitive like a """neuronal""" network or LLM was always ridiculous.
calepayson 2y ago
To anyone interested in this article I highly recommend “The Cerebral Code” by William Calvin. (https://williamcalvin.com/bk9/index.htm https://williamcalvin.com/bk9/index.htm) It’s the only theory of how the brain works that I’ve come across that seems like it could be valid. Unfortunately, like other posters have already mentioned, neuroscience is incredibly complex and we just don’t have the tools to test it. Even if it ends up being completely wrong, it’s a beautiful theory and well worth checking out!
- dleeftink 2y ago
  The cerebral code as an ensemble of signals, music. Or rather, music as metaphor of neuronal patterning. Gives another dimension to being 'in tune' with someone. I think the clinical shift to focus on 'the individual' instead of the ensemble has overlooked the importance of inter-brain synchronisation, the process of which we are only start to grapple [0]. A feeling all to familiar to fellow musicians, and no doubt anyone involved in activities in which timing coordination is key. [0]: https://www.sciencedirect.com/science/article/abs/pii/S0149763424002811 https://www.sciencedirect.com/science/article/abs/pii/S01497...
  - calepayson 2y ago
    > Gives another dimension to being 'in tune' with someone. Love this. > I think the clinical shift to focus on 'the individual' instead of the ensemble has overlooked the importance of inter-brain synchronisation My sense is this is also the case for our cultural story of neuroscience. We can run massive analysis of the brain and what brain regions or neurons or transmitters are being used/activated and it all boils down to something we can't conceptualize. Even the principal components seem to be too complex for us to grock. With this barrage of complexity I feel like we have a (bad but understandable) habit of reducing to the individual. We talk about the grandmother neuron or what region x is responsible for. We harp on the cog sci of individuals and we run experiments where we try to isolate them for "confounding factors" (other people). I keep coming back to evolutionary theory as the middle ground between this over and under simplification of cognition.
damnitbuilds 2y ago
Think this is bad? Psychology is worse, much worse, and yet is used around the world to make many, many life-changing or life-ending decisions.
- jajko 2y ago
  Which part of psychology? To me as a layman, getting interested in what makes people tick, how different issues manifest, how bad childhood and especially missing good father figure affects people proved invaluable. But I dont mean clinical psychology, university textbooks etc but rather easy to digest popular stuff from ie Jordan Peterson (before he got addicted and crazy). Understanding (ex)girlfriends, colleagues, parents, politicians, everybody and especially myself. People cant shock or surprise me these days.
- mvieira38 2y ago
  Maybe off topic: I can't for the life of me figure out how therapy isn't a scam. CBT as proposed and studied in lab settings can't really be applied in the wild like most evidence based therapists try to, and the results of therapy I come across always seem extremely underwhelming. Maybe for some cases like severe phobias there is something to be solved, but do we really need to be paying thousands of dollars a year for a therapist to say "hey, maybe if you'd invest more in hobbies, social relationships and a healthy lifestyle you would feel better"?
  - bildung 2y ago
    > CBT as proposed and studied in lab settings can't really be applied in the wild like most evidence based therapists try to, Because that part is wrong, apart from the underlying inner working being dissected in labs (the cognitive science part), the therapy part it is well studied in the wild - and it works. > and the results of therapy I come across always seem extremely underwhelming. So you mean anecdotes? Of course you recognize the underwhelming results - the people where it worked well are less noticable, by definition. > Maybe for some cases like severe phobias there is something to be solved, but do we really need to be paying thousands of dollars a year That you have to pay money has been a decision of the society you reside in. It doesn't have to be this way, and in fact it isn't in most industrialized countries. > for a therapist to say "hey, maybe if you'd invest more in hobbies, social relationships and a healthy lifestyle you would feel better"? That is a strawman, not CBT.
dvh 2y ago
"Human brain is too big to be understood with current technology, that's why scientists use simpler organisms to study brain. Flatworm's brain has 52 neurons. We have no idea how it works." I've read this few years ago, how far we've come?
- xkcd-sucks 2y ago
  Just for cultural reasons, a roundworm's brain with 302 neurons (each one always in the same place spatially and topologically I might add) is likely better understood. And we don't have a great idea of how it works. But the OpenWorm simulation project seems to have current development https://github.com/orgs/openworm/repositories https://github.com/orgs/openworm/repositories
leptoniscool 2y ago
it looks like we can now actually use brains as computers: https://corticallabs.com/ https://corticallabs.com/
- perching_aix 2y ago
  i'm simultainously unsurprised and blown away. i should rewatch the anime Psycho Pass sometime.
  - Gooblebrai 2y ago
    How is the anime related?
    - perching_aix 2y ago
      The show is oriented around a fictitious law enforcement technology called the Sibyl System. This system is capable of determining the intent of people, and based on that, it can predict crimes and criminal intent, allowing law enforcement to preventively take action. The kicker is, as the MC learns, that there are people who the system doesn't seem to work on. Minor(?) plot point spoiler ahead for season one: Later on the story the main character further learns that the system is actually a mainframe made up of living human brains connected together. Hence the relation.
- Gooblebrai 2y ago
  I'm really fascinated by the idea of biological computers. Doesn't get enough recognition.
pedalpete 2y ago
We keep plugging biology into our understanding of physics, which I believe, is the greatest limitation to our understanding. We don't know what we don't know. What I mean by this is that we thought we understood the body when we understood thermodynamics. The blood pumps through the heart, goes to the brain, nutrients feed the muscles, etc etc. Then we discovered how electricity works and we thought "oh! of course, it's all electric!" The heart pumps because of electricity, and the nerves are all electric synapses, etc etc. I fully expect in the future we will look at quantum mechanics and apply that to our understanding of biology (if we aren't doing that yet), and down the rabbit hole we will continue. That doesn't mean we can't do some incredible things with our current understanding of the brain, I work in neurotech at https://affectablesleep.com https://affectablesleep.com, where we are increasing the effectiveness of deep sleep. We know the mechanism we can use to trick the brain to increasing the synchronous firing of neurons which define deep sleep, but we don't know WHY it works.
- yubblegum 2y ago
  > I fully expect in the future we will look at quantum mechanics and apply that to our understanding of biology Heisenberg would like to have a word with you. He wrote Reality and its Order during the war (world war 2 that is) and obviously he knew his quantum mechanics. "From the point of view of present atomic theory, the organism appears to be an utterly improbable formation". https://link.springer.com/book/10.1007/978-3-030-25696-8 https://link.springer.com/book/10.1007/978-3-030-25696-8
  - pedalpete 2y ago
    I'm probably not as well versed in quantum as you are, but the way I'm reading that quote, isn't everything in quantum theory "an utterly improbable formation"? I can't tell if you are disagreeing with my initial comment or agreeing. Sorry for being a bit slow on the uptake on this.
    - yubblegum 2y ago
      Just like you I am just a somewhat informed layperson as far as QM is concerned, which is the reason Heisenberg was dragged into the conversation. I invite you to read his book -- he wrote it to share his thoughts with friends and family so it is an 'accessible' text modulo obviously being the thoughts of a very rigorous and powerful mind, so it's not a breezy pop treatment either. Heisenberg begins with an abstract consideration of language and correspondence of expressions in a language to a given 'context' or domain of understanding. He then uses this framework to progressively consider distinct domains or contexts of knowledge (celestial mechanics, EM, QM, Chemistry, Biology ..) by noting the content of their respective languages and their relationship to one another. For example, Newtonian mechanics has the vocabulary of force, mass, acceleration, etc. Then he notes how Electro-Magnetism necessitated the introduction of new terms, most importantly (force) fields. He then notes, as an example, how 19th century mechanics (alone) could not explain the stability of the atomic ensemble, which is what gave birth to QM. In all this, his main point is that each of these domains are 'closed' and complete in terms of phenomena that they are expressing, but are not universally complete. For example, basic (Newtonian) mechanics can fully explain the motion of an automobile, but if you want to understand what is happening with say the brakepads on a car when it is decelerating, we need to introduce the langauge of 'heat' and effectively Chemistry. In terms of "organic matter", he muses on the fact that there is clearly something different about "living matter" and "dead matter", yet as of then (or now) we see that the same physical laws (chemical and QM) are operable in both modalities of matter, yet clearly something is different. He refers to the then current theories of vitalism and entelechy and also the thoughts of his mentor (Bohr) who apparently projected his overarching 'guiding thought' of "complementarity" to the question of living matter. At some point he also considers the possiblity that all 'organic matter' and "consciousness" may somehow be related. As to "improbable", he takes pain to point out distinction between "objective" and "subjective" understanding of a system or phenomena. (This is likely due to his following in the footsteps of Goethe, whom he references.) QM can give "very precise" predictions regarding "a specific aspect" of a (complex) system, say momentum, but the other aspects of the system can only be defined statistically. In all this, what is clear is that as of 1940-whatever neither Heisenberg nor Bohr thought QM as a language that is 'closed' over organic matter, to say nothing of consciousness. Hope this clarifies.

101 points by Gooblebrai 2y ago

deleted 2y ago

[deleted]

curtisszmania 2y ago

[dead]

bena 2y ago

I would think a large part of the problem is the difficulty in observing a working brain. There are very few non-destructive ways we can get a look into a brain while it is living. And even research into ways we can look into a living brain is hindered by the fact we don't want to harm the person being observed. I could see that making progress a lot slower

jampekka 2y ago
> And even research into ways we can look into a living brain is hindered by the fact we don't want to harm the person being observed. Animal brains are harmed for research all the time. Some species, like Zebrafish can be even imaged real-time at neuronal level. As the article says, the problem is really that there are no good foundational ideas of what are the basic operating principles of the brain.
- bena 2y ago
  I did mention people specifically. Mammalian brains are fairly more complex than piscine brains. People are important because we can't tell a fish to perform an action or to think of an elephant, etc. So while we can image, we can't know what correlates with a high degree of certainty. But even in other cases, a working brain is an entirely different object than a non-working one. Finding those foundational ideas and basic operating principles because we can't test a living brain. It's almost chicken/egg. Being able to experiment on a living human brain would probably give us much better ideas of the basic operating principles. And once we know those principles, we could probably move from experimenting on living human brains. Like, we can dick around with muscle. We can force it to perform as it were living and receiving signals. And that's partly because you can cut open a living person and watch those muscles operate. You can manipulate those muscles in a living person. You can measure things, etc. It's much harder to do that with a brain. Because it's incredibly easy to make irredeemable mistakes.
  - glenstein 2y ago
    >So while we can image, we can't know what correlates with a high degree of certainty. I don't think I agree just on this piece, though you are making important points here. We can know, for instance, of visual or spacial awareness, reactions to certain stimuli or objects introduced in their environment, and so on. You're not wrong on the importance of learning from active brain functions but I think we can at least make meaningful inroads with animals. > Finding those foundational ideas and basic operating principles I know a lot of people talk this way about brains and consciousness, that we need to first have our definitional elements before we proceed with research. But I think we often have, as the object of research, closing in on those elements, while gathering all kinds of functional and theoretical data from the mass of complicated noise that is brain structure and activity. We can build out correlations, mechanisms, and so on and close in on foundational elements. It may even be the case that foundational organizing principles turn our understanding inside out in important ways, but I have never understood the idea that we are stuck if we can't start with such things in hand.
    - bena 2y ago
      I'm sorry, I see where I wasn't clear. I'm talking about very specific correlation. Like when I type these words, exactly how and what fires to achieve that. Which neurons and pathways are the thought "hit these keys", what's the signal to the fingers etc. We know "When this area is active, this group of actions can happen". It's hard to get good resolution. And I believe it would be easier to replicate consciousness if we knew how it worked, I also believe it's possible we eventually figure it out. It will just be much harder. And we may not know when we do it either. I believe that is where we will need common, agreed upon definitions. But defining intelligence and consciousness is difficult because you have to define it in a way that includes everything we agree is conscious and excludes everything we agree is not. And we'll also have to agree what is and is not conscious. It's a way more involved problem than a lot of people give credit.
      - glenstein 2y ago
        >But defining intelligence and consciousness is difficult because you have to define it in a way that includes everything we agree is conscious and excludes everything we agree is not. I think this is extremely important, but I would say that methodologically, messy definitions can nevertheless be stepping stones that bring us closer to full comprehension of definitions. I suppose I just have a specific hobby horse in this context and I don't know that I'm responding to you so much as a general idea I've seen elsewhere, that you're rhyming with, which is this idea that research has to start from agreed upon definitions. I would say instead that there are such things as characteristic instances that embody lots of the stuff we are interested in, such that we can say "whatever consciousness is, it involves that" and we can just point to something that's a wild, underdefined phenomenon, and make it subject of study. Without a definition, I can still understand that states of mind that involve, say, wakeful awareness and intention are going to be about consciousness. We can know necessary conditions even if we don't know "sufficient" conditions, and the former are a stepping stone to comprehending the latter.
mbauman 2y ago
The even bigger challenge is determining _what_ you need to observe in the first place. As a simplistic analogy, evolutionary designs of FPGA boards can end up relying upon idiosyncratic properties of the board(s) and create circuits that "shouldn't work" based on an idealized electrical circuit model. And they may not be transferable to other boards. In other words, to "understand" some evolutionary FPGA circuits, you need to "observe" more than just the gate configurations and idealized schematic. Brains are not FPGAs or even circuits, but I think the analogy holds. They're not _just_ idealized representations of spiking neural networks.
- NoxiousPluK 2y ago
  I remember reading an article about this years ago - a non-transferable FPGA configuration which had some logic that should be unreachable but didn't work without it. Very faschinating but I've not been able to find it since.
  - nick__m 2y ago
    I think you want that paper "An Evolved Circuit, Intrinsic in Silicon, Entwined with Physics" available there https://cgi.cse.unsw.edu.au/~cs4601/refs/papers/es97thompson.pdf https://cgi.cse.unsw.edu.au/~cs4601/refs/papers/es97thompson...
tim333 2y ago
I agree and think the way forward is computer simulation. Figure out a simulation equivalent of a neuron and put a lot together and see how well the simulated brain portion matches the real thing. That hasn't really been possible due to lack capability of computer power but we are getting to where it could be. They have of course done stuff with "artificial neural networks" of the ChatGPT type but those are very far from biology. DeepMind has been doing work along those lines with 'AI BRAIN' https://medium.com/@daneallist/unlocks-secrets-of-real-brains-google-deepmind-ai-brain-5f51214b3d35 https://medium.com/@daneallist/unlocks-secrets-of-real-brain...
- renewedrebecca 2y ago
  How do you simulate something you don't understand? The basic problem here is that we don't understand what a neuron does, so how would we model it?
  - deleted 2y ago
    [deleted]
  - KineticLensman 2y ago
    > The basic problem here is that we don't understand what a neuron does, so how would we model it? We understand lots of aspects of neurons and can model those. See the wikipedia page for some examples of well-understood principles.
    - tim333 2y ago
      Yeah and you can do a simulation using a rough approximation and then it is interesting to see in what ways it matches real brains and in what it does not. It seems the DeepMind rat brain didn't really try to get close to biological neurons but still produced outputs close to a real brain. (vid from here for about 2 mins https://youtu.be/hIuXXvWY6-4?t=125 https://youtu.be/hIuXXvWY6-4?t=125)
  - deleted 2y ago
    [deleted]
seejayjordan 2y ago
Look up Wada Test, where we shut down each hemisphere (one at a time) of the brain, while the patient is awake, to see how their personality changes without 1/2 their brain. Also stereo EEG. 200+ sensors placed in/on/around the brain, patient stays in bed for a week measuring brain activity. Here's the kicker... neurologists can plug into the brain and send teeny bits of electricity to each of the 200+ sensors individually to see what happens (typically this is for identifying seizure spots). Wish I didn't have to know this, but my partner is very epileptic, and has an RNS device implanted in her head. We upload her brain activity daily!
- Gooblebrai 2y ago
  According to Wikipedia the personality barely changes and the tests is mainly done to detect which side is on charge of language and memory

imchillyb 2y ago

We are just now uncovering an underlying principle of science: ‘everything is a wave.’ Neurological connective tissues and their corresponding signals may be more of a symptom of electrical wave action rather than a signaling nexus. Everything is a wave. Everything is a probabilistic wave form with probabilistic outcomes. Once science understands these waves and their myriad forms, we may have a greater understanding of our own wires and grey matter signaling.

guappa 2y ago
We understand gravity and the 3 body problem still exists…
- 0x1ceb00da 2y ago
  We just don't have a general solution of the 3 body problem in the form of equations. Practically speaking it's a solved problem because we can simulate the motion. We could do the same with brain. That's basically what neural networks are.
  - willy_k 2y ago
    We can simulate the three body problem because all of the significant parts of the problem can be known. This is FAR from the case when it comes to the brain.
  - goatlover 2y ago
    Neural networks are not simulations of neurons.
  - Gooblebrai 2y ago
    Can we simulate it indefinitely? I thought chaotic behaviour entered the game at some point.

prismatix 2y ago

If you find this interesting, the Theories of Everything podcast with Curt Jaimungal does a good job exploring this topic. The neuroscience-centered conversations focus mostly on consciousness, but they still discuss similar problems with measuring and explaining how consciousness comes about from a collection of matter.

intrasight 2y ago

I took a break from artificial networks to study neuroscience for a couple years. We hardly understand how a single synapse works - and we have trillions of them.

minihat 2y ago
This is exactly right. I started a PhD in 2017 studying neuroscience + ML. I thought studying the brain would help me understand ANNs better. I was wrong. Ended up applying ML to analyzing EEG, MRI and similar.
- bumby 2y ago
  Is this because we're misapplying the analogy to ML? I.e., in an effort to communicate and understand ANNs, we "pretend" it's like a brain. Just like before, we used "file retrieval systems" to understand the brain, or electricity is like "water in a pipe", which are also wrong. Analogies often only go so far, beyond which they do more harm than good.
  - beezlebroxxxxxx 2y ago
    What you're describing is endemic across HN (and tech, tbh). Lots of people on here "know" computers/programming/CS very well. They, naturally, tend to use analogies to computers/programming/CS when trying to explain or "think out loud" in their comments. That's fine. It's what they know. The common problem arises when people forget they're analogizing and begin to see their analogy as ontologically and conceptually identical to the thing they were making an analogy for. This requires a certain amount of ego, echo chambers, and self-valorization, so that they never have to face the actual issues with these analogies. But as many comments here have pointed out, studying neuroscience, for example, usually makes those analogies seem painfully inadequate. The same is true in philosophy of mind, for example.
  - SkyBelow 2y ago
    Have we hit the limit of the analogy, or have we hit a limit in our understanding? Both neural networks and actual brains have behaviors that emerge from the interactions of smaller components. Neural networks have trivial connections compared to brains, but our understanding of the emergent behaviors seems very limited. To me, this is a sign not that the analogy has reached a point of breaking down, but that our tools aren't sufficient to work on even then trivial connections. I do expect the analogy will break at some point, but I'm not sure we have reached that point yet.

teqsun 2y ago

This is the main reason why I have skepticism towards any claims of imminent AGI.

mellosouls 2y ago
I'm also sceptical but to be fair, we don't need to understand how the brain works for AGI, that's just one (obvious) path.
- JackFr 2y ago
  Who knows? Maybe it’ll turn out like flying and birds. Studying birds gave us some data, but mimicking them wasn’t what got us jumbo jets.
  - southernplaces7 2y ago
    Sort of a shame... I always wanted to fly in an ornithopter.
- southernplaces7 2y ago
  Since we don't yet have anything remotely like AGI and at the same time, don't even really know how the brain works or what consciousness is aside from being aware that we feel it, you and nobody else really know if our path to consciousness is just one of many. For all we know it might be the only one. There could be some very big unknown unknowns in those waters.
  - glenstein 2y ago
    I would say I think those are all pretty good observations, all perfectly true and I think AGI is more plausible than it's ever been in light of what we've demonstrated via LLMs. Our understanding really is that limited but I don't take it to be a counterpoint to the prospect of AGI.
  - Traubenfuchs 2y ago
    > what consciousness is Probably an unavoidable property that emerges from the sheer and perverse complexity of the human brain, its 100 billion connections and the unimaginable amount of interactions between them, modulated by neurotransmitters + their reuptake, length, amount, location, quality and condition of pre/post-synaptic receptors, axons and other nano structures in the brain... Comparing this disgusting moist, fleshy and electric masterpiece of nature with something primitive like a """neuronal""" network or LLM was always ridiculous.

calepayson 2y ago

To anyone interested in this article I highly recommend “The Cerebral Code” by William Calvin. (https://williamcalvin.com/bk9/index.htm https://williamcalvin.com/bk9/index.htm) It’s the only theory of how the brain works that I’ve come across that seems like it could be valid. Unfortunately, like other posters have already mentioned, neuroscience is incredibly complex and we just don’t have the tools to test it. Even if it ends up being completely wrong, it’s a beautiful theory and well worth checking out!

dleeftink 2y ago
The cerebral code as an ensemble of signals, music. Or rather, music as metaphor of neuronal patterning. Gives another dimension to being 'in tune' with someone. I think the clinical shift to focus on 'the individual' instead of the ensemble has overlooked the importance of inter-brain synchronisation, the process of which we are only start to grapple [0]. A feeling all to familiar to fellow musicians, and no doubt anyone involved in activities in which timing coordination is key. [0]: https://www.sciencedirect.com/science/article/abs/pii/S0149763424002811 https://www.sciencedirect.com/science/article/abs/pii/S01497...
- calepayson 2y ago
  > Gives another dimension to being 'in tune' with someone. Love this. > I think the clinical shift to focus on 'the individual' instead of the ensemble has overlooked the importance of inter-brain synchronisation My sense is this is also the case for our cultural story of neuroscience. We can run massive analysis of the brain and what brain regions or neurons or transmitters are being used/activated and it all boils down to something we can't conceptualize. Even the principal components seem to be too complex for us to grock. With this barrage of complexity I feel like we have a (bad but understandable) habit of reducing to the individual. We talk about the grandmother neuron or what region x is responsible for. We harp on the cog sci of individuals and we run experiments where we try to isolate them for "confounding factors" (other people). I keep coming back to evolutionary theory as the middle ground between this over and under simplification of cognition.

damnitbuilds 2y ago

Think this is bad? Psychology is worse, much worse, and yet is used around the world to make many, many life-changing or life-ending decisions.

jajko 2y ago
Which part of psychology? To me as a layman, getting interested in what makes people tick, how different issues manifest, how bad childhood and especially missing good father figure affects people proved invaluable. But I dont mean clinical psychology, university textbooks etc but rather easy to digest popular stuff from ie Jordan Peterson (before he got addicted and crazy). Understanding (ex)girlfriends, colleagues, parents, politicians, everybody and especially myself. People cant shock or surprise me these days.
mvieira38 2y ago
Maybe off topic: I can't for the life of me figure out how therapy isn't a scam. CBT as proposed and studied in lab settings can't really be applied in the wild like most evidence based therapists try to, and the results of therapy I come across always seem extremely underwhelming. Maybe for some cases like severe phobias there is something to be solved, but do we really need to be paying thousands of dollars a year for a therapist to say "hey, maybe if you'd invest more in hobbies, social relationships and a healthy lifestyle you would feel better"?
- bildung 2y ago
  > CBT as proposed and studied in lab settings can't really be applied in the wild like most evidence based therapists try to, Because that part is wrong, apart from the underlying inner working being dissected in labs (the cognitive science part), the therapy part it is well studied in the wild - and it works. > and the results of therapy I come across always seem extremely underwhelming. So you mean anecdotes? Of course you recognize the underwhelming results - the people where it worked well are less noticable, by definition. > Maybe for some cases like severe phobias there is something to be solved, but do we really need to be paying thousands of dollars a year That you have to pay money has been a decision of the society you reside in. It doesn't have to be this way, and in fact it isn't in most industrialized countries. > for a therapist to say "hey, maybe if you'd invest more in hobbies, social relationships and a healthy lifestyle you would feel better"? That is a strawman, not CBT.

dvh 2y ago

"Human brain is too big to be understood with current technology, that's why scientists use simpler organisms to study brain. Flatworm's brain has 52 neurons. We have no idea how it works." I've read this few years ago, how far we've come?

xkcd-sucks 2y ago
Just for cultural reasons, a roundworm's brain with 302 neurons (each one always in the same place spatially and topologically I might add) is likely better understood. And we don't have a great idea of how it works. But the OpenWorm simulation project seems to have current development https://github.com/orgs/openworm/repositories https://github.com/orgs/openworm/repositories

leptoniscool 2y ago

it looks like we can now actually use brains as computers: https://corticallabs.com/ https://corticallabs.com/

perching_aix 2y ago
i'm simultainously unsurprised and blown away. i should rewatch the anime Psycho Pass sometime.
- Gooblebrai 2y ago
  How is the anime related?
  - perching_aix 2y ago
    The show is oriented around a fictitious law enforcement technology called the Sibyl System. This system is capable of determining the intent of people, and based on that, it can predict crimes and criminal intent, allowing law enforcement to preventively take action. The kicker is, as the MC learns, that there are people who the system doesn't seem to work on. Minor(?) plot point spoiler ahead for season one: Later on the story the main character further learns that the system is actually a mainframe made up of living human brains connected together. Hence the relation.
Gooblebrai 2y ago
I'm really fascinated by the idea of biological computers. Doesn't get enough recognition.

pedalpete 2y ago

We keep plugging biology into our understanding of physics, which I believe, is the greatest limitation to our understanding. We don't know what we don't know. What I mean by this is that we thought we understood the body when we understood thermodynamics. The blood pumps through the heart, goes to the brain, nutrients feed the muscles, etc etc. Then we discovered how electricity works and we thought "oh! of course, it's all electric!" The heart pumps because of electricity, and the nerves are all electric synapses, etc etc. I fully expect in the future we will look at quantum mechanics and apply that to our understanding of biology (if we aren't doing that yet), and down the rabbit hole we will continue. That doesn't mean we can't do some incredible things with our current understanding of the brain, I work in neurotech at https://affectablesleep.com https://affectablesleep.com, where we are increasing the effectiveness of deep sleep. We know the mechanism we can use to trick the brain to increasing the synchronous firing of neurons which define deep sleep, but we don't know WHY it works.

yubblegum 2y ago
> I fully expect in the future we will look at quantum mechanics and apply that to our understanding of biology Heisenberg would like to have a word with you. He wrote Reality and its Order during the war (world war 2 that is) and obviously he knew his quantum mechanics. "From the point of view of present atomic theory, the organism appears to be an utterly improbable formation". https://link.springer.com/book/10.1007/978-3-030-25696-8 https://link.springer.com/book/10.1007/978-3-030-25696-8
- pedalpete 2y ago
  I'm probably not as well versed in quantum as you are, but the way I'm reading that quote, isn't everything in quantum theory "an utterly improbable formation"? I can't tell if you are disagreeing with my initial comment or agreeing. Sorry for being a bit slow on the uptake on this.
  - yubblegum 2y ago
    Just like you I am just a somewhat informed layperson as far as QM is concerned, which is the reason Heisenberg was dragged into the conversation. I invite you to read his book -- he wrote it to share his thoughts with friends and family so it is an 'accessible' text modulo obviously being the thoughts of a very rigorous and powerful mind, so it's not a breezy pop treatment either. Heisenberg begins with an abstract consideration of language and correspondence of expressions in a language to a given 'context' or domain of understanding. He then uses this framework to progressively consider distinct domains or contexts of knowledge (celestial mechanics, EM, QM, Chemistry, Biology ..) by noting the content of their respective languages and their relationship to one another. For example, Newtonian mechanics has the vocabulary of force, mass, acceleration, etc. Then he notes how Electro-Magnetism necessitated the introduction of new terms, most importantly (force) fields. He then notes, as an example, how 19th century mechanics (alone) could not explain the stability of the atomic ensemble, which is what gave birth to QM. In all this, his main point is that each of these domains are 'closed' and complete in terms of phenomena that they are expressing, but are not universally complete. For example, basic (Newtonian) mechanics can fully explain the motion of an automobile, but if you want to understand what is happening with say the brakepads on a car when it is decelerating, we need to introduce the langauge of 'heat' and effectively Chemistry. In terms of "organic matter", he muses on the fact that there is clearly something different about "living matter" and "dead matter", yet as of then (or now) we see that the same physical laws (chemical and QM) are operable in both modalities of matter, yet clearly something is different. He refers to the then current theories of vitalism and entelechy and also the thoughts of his mentor (Bohr) who apparently projected his overarching 'guiding thought' of "complementarity" to the question of living matter. At some point he also considers the possiblity that all 'organic matter' and "consciousness" may somehow be related. As to "improbable", he takes pain to point out distinction between "objective" and "subjective" understanding of a system or phenomena. (This is likely due to his following in the footsteps of Goethe, whom he references.) QM can give "very precise" predictions regarding "a specific aspect" of a (complex) system, say momentum, but the other aspects of the system can only be defined statistically. In all this, what is clear is that as of 1940-whatever neither Heisenberg nor Bohr thought QM as a language that is 'closed' over organic matter, to say nothing of consciousness. Hope this clarifies.