[HN Gopher] Cubic millimetre of brain mapped in spectacular detail
       ___________________________________________________________________
        
       Cubic millimetre of brain mapped in spectacular detail
        
       Author : geox
       Score  : 203 points
       Date   : 2024-05-09 21:36 UTC (1 days ago)
        
 (HTM) web link (www.nature.com)
 (TXT) w3m dump (www.nature.com)
        
       | teuobk wrote:
       | The interactive visualization is pretty great. Try zooming in on
       | the slices and then scrolling up or down through the layers. Also
       | try zooming in on the 3D model. Notice how hovering over any part
       | of a neuron highlights all parts of that neuron:
       | 
       | http://h01-dot-neuroglancer-demo.appspot.com/#!gs://h01-rele...
        
         | jamiek88 wrote:
         | My god. That is stunning.
         | 
         | To think that's one single millimeter of our brain and look at
         | all those connections.
         | 
         | Now I understand why crows can be so smart walnut sized brain
         | be damned.
         | 
         | What an amazing thing brains are.
         | 
         | Possibly the most complex things in the universe.
         | 
         | Is it complex enough to understand itself though? Is that
         | logically even possible?
        
           | ignoramous wrote:
           | I wonder if we manage to annotate this much level of detail
           | about our brain, and then let (some variant of the current)
           | models train on it, will those intrinsically end up
           | generalizing a model for intelligence?
        
             | nicklecompte wrote:
             | I think you would also need the epigenetic side, which is
             | very poorly understood:
             | https://www.universityofcalifornia.edu/news/biologists-
             | trans...
             | 
             | We have more detail than this about the C. elegans nematode
             | brain, yet we still no clue how nematode intelligence
             | actually works.
        
               | Animats wrote:
               | How's OpenWorm coming along?
        
               | nicklecompte wrote:
               | Badly:
               | https://www.lesswrong.com/posts/mHqQxwKuzZS69CXX5/whole-
               | brai... (the comments have some updates as of 2023)
               | 
               | Almost every other cell in the worm can be simulated with
               | known biophysics. But we don't have a clue how any
               | individual nematode neuron actually works. I don't have
               | the link but there are a few teams in China working on
               | visualizing brain activity in _living_ C. elegans, but it
               | 's difficult to get good measurements without affecting
               | the behavior of the worm (e.g. reacting to the dye).
        
           | nicklecompte wrote:
           | Crow/parrot brains are tiny but in terms of neuron count they
           | are twice as dense as primate brains (including ours): https:
           | //www.sciencedirect.com/science/article/pii/S096098221...
           | 
           | If someone did this experiment with a crow brain I imagine it
           | would look "twice as complex" (whatever that might mean). 250
           | million years of evolution separates mammals from birds.
        
             | jamiek88 wrote:
             | Interesting! Thank you. I didn't know that.
        
             | Terr_ wrote:
             | I expect we'll find that it's all a matter of tradeoffs in
             | terms of count vs size/complexity... kind of like how the
             | "spoken data rate" of various human languages seems to be
             | the same even though some have complicated big words versus
             | more smaller ones etc.
        
               | sdenton4 wrote:
               | Birds are under a different set of constraints than non-
               | bat mammals, of course... They're very different.
               | Songbirds have ~4x finer time Perception of audio than
               | humans do, for example, which is exemplified by taking
               | complex sparrow songs and showing them down until you can
               | actually hear the fine structure.
               | 
               | The human 'spoken data rate' is likely due to average
               | processing rates in our common hardware. Birds have a
               | different architecture.
        
               | Terr_ wrote:
               | You misunderstand, I'm not making any kind of direct
               | connection between human speech and bird song.
               | 
               | I'm saying we will probably discover that the "overall
               | performance" of different vertebrate neural setups are
               | clustered pretty closely, even when the neurons are
               | arranged rather differently.
               | 
               | Human speech is just an example of another kind of
               | performance-clustering, which occurs for similar
               | metaphysical reasons between competing, evolving, related
               | alternatives.
        
             | pfdietz wrote:
             | That shouldn't be too surprising, as a larger fraction of
             | the volume of a brain should be taken up by "wiring" as the
             | size of the brain expands.
        
             | steve_adams_86 wrote:
             | This might be a dumb question, because I doubt the
             | distances between neurons makes a meaningful distance...
             | But could a small brain, dense with neurons like a crow,
             | possibly lead to a difference in things like response to
             | stimuli or "compute" speed so to speak?
        
               | michaelhoney wrote:
               | Actually I think that's pretty plausible. Signal speed in
               | the brain is pretty slow - it would have to make some
               | difference
        
               | out_of_protocol wrote:
               | Regarding compute speed - it checks out. Humans "think"
               | via neo cortex, thin ouside layer of the brain. Poor
               | locality, signals needs to travel a lot. Easy to expand
               | though. Crow brain have everything tightly concentrated
               | in the center - fast communication between neurons, hard
               | to have more "thinking" thing later (therefore hard to
               | evolve above what crows currently have)
        
             | LargoLasskhyfv wrote:
             | IIRC bird brains are 'packed/structured' very similar to
             | our cerebellum.
             | 
             | So one would just need to pick that little cube out of our
             | cerebellum, to have that 'twice as complexity'.
        
             | djmips wrote:
             | It's amusing to say that bird brains are on the next
             | generation node size.
        
           | layer8 wrote:
           | We don't know what "understanding" means (we don't have a
           | workable definition of it), so your question cannot be
           | answered.
        
         | gofreddygo wrote:
         | That is awesome !
         | 
         | the sheer number of things that work in co-ordination to make
         | biology work!
         | 
         | In-f*king-credible !
        
         | oniony wrote:
         | Hmm, that website does not honour my keyboard layout. Not sure
         | how they managed that.
        
       | CSSer wrote:
       | For some people, this is all you need (sorry, couldn't resist)!
        
       | eminence32 wrote:
       | > cut the sample into around 5,000 slices -- each just 34
       | nanometres thick -- that could be imaged using electron
       | microscopes.
       | 
       | Does anyone have any insight into how this is done without
       | damaging the sample?
        
         | talsit wrote:
         | Using a Microtome (https://en.m.wikipedia.org/wiki/Microtome).
        
         | dekhn wrote:
         | The sample is stained (to make thigns visible), then embedded
         | in a resin, then cut with a very sharp diamond knife and the
         | slices are captured by the tape reel.
         | 
         | Paper:
         | https://www.biorxiv.org/content/10.1101/2021.05.29.446289v4 See
         | Figure 1.
         | 
         | The ATUM is described in more detail here https://www.eden-
         | instruments.com/en/ex-situ-equipments/rmc-e...
         | 
         | and there's a bunch of nice photos and explanations here
         | https://www.wormatlas.org/EMmethods/ATUM.htm
         | 
         | TL;DR this project is reaping all the benefits of the 21st
         | century.
        
       | posnet wrote:
       | 1.4 PB/mm^3 (petabytes per millimeter cubed)x1260 cm^3 (cubic
       | centimeters, large human brain) = 1.76x10^21 bytes = 1.76 ZB
       | (zetabytes)
        
         | bahrant wrote:
         | wow
        
         | gary17the wrote:
         | [AI] "Frontier [supercomputer]: the storage capacity is
         | reported to be up to 700 petabytes (PB)" (0.0007 ZB).
         | 
         | [AI] "The installed base of global data storage capacity [is]
         | expected to increase to around 16 zettabytes in 2025".
         | 
         | Thus, even the largest supercomputer on Earth cannot store more
         | than 4 percent of state of a single human brain. Even all the
         | servers on the entire Internet could store state of only 9
         | human brains.
         | 
         | Astonishing.
        
           | dekhn wrote:
           | One point about storage- it's economically driven. If there
           | was a demand signal (say, the government dedicated a few
           | hundred billion dollars to a single storage systems), hard
           | drive manufacturers could deploy much more storage in a year.
           | I've pointed this out to a number of scientists, but none of
           | them could really think of a way to get the government to
           | spend that much money just to store data without it curing a
           | senator's heart disease.
        
             | falcor84 wrote:
             | > without it curing a senator's heart disease
             | 
             | Obviously I'm not advocating for this, but I'll just link
             | to the Mad TV skit about how the drunk president cured
             | cancer.
             | 
             | https://www.youtube.com/watch?v=va71a7pLvy8
        
           | falcor84 wrote:
           | I appreciate you're running the numbers to extrapolate this
           | approach, but just wanted to note that this particular figure
           | isn't an upper bound nor a longer bound for actually storing
           | the "state of a single human brain". Assuming the intent
           | would be to store the amount of information needed to
           | essentially "upload" the mind onto a computer emulation, we
           | might not yet have all the details we need in this kind of
           | scanning, but once we do, we may likely discover that a huge
           | portion of it is redundant.
           | 
           | In any case, it seems likely that we're on track to have both
           | the computational ability and the actual neurological data
           | needed to create an "uploaded intelligences" sometime over
           | the next decade. Lena [0] tells of the first successfully
           | uploaded scan taking place in 2031, and I'm concerned that
           | reality won't be far off.
           | 
           | [0] https://qntm.org/mmacevedo
        
             | rmorey wrote:
             | we are nowhere near whole human brain volume EM. the next
             | major milestone in the field is a whole mouse brain in the
             | next 5-10 years, which is possible but ambitious
        
               | falcor84 wrote:
               | What am I missing? Assuming exponential growth in
               | capability, that actually sounds very on track. If we can
               | get from 1 cubic millimeter to a whole mouse brain in
               | 5-10 years, why should it take more than a few extra
               | years to scale that to a human brain?
        
               | rmorey wrote:
               | assuming exponential growth in capacity is a big
               | assumption!
        
             | gary17the wrote:
             | > we may likely discover that a huge portion of [a human
             | brain] is redundant
             | 
             | Unless one's understanding of algorithmic inner workings of
             | a particular black box system is actually very good, it is
             | likely not possible not only to discard any of its state,
             | but even implement any kind of meaningful error detection
             | if you do discard.
             | 
             | Given the sheer size and complexity of a human brain, I
             | feel it is actually very unlikely that we will be able to
             | understand its inner workings to such a significant degree
             | anytime soon. I'm not optimistic, because so far we have no
             | idea how even laughingly simple, in comparison, AI models
             | work[0].
             | 
             | [0] "God Help Us, Let's Try To Understand AI
             | Monosemanticity", https://www.astralcodexten.com/p/god-
             | help-us-lets-try-to-und...
        
             | RaftPeople wrote:
             | > _In any case, it seems likely that we 're on track to
             | have both the computational ability and the actual
             | neurological data needed to create an "uploaded
             | intelligences" sometime over the next decade._
             | 
             | They don't even know how a single neuron works yet. There
             | is complexity and computation at many scales and
             | distributed throughout the neuron and other types of cells
             | (e.g. astrocytes) and they are discovering more
             | relentlessly.
             | 
             | They just recently (last few years) found that dendrites
             | have local spiking and non-linear computation prior to
             | forwarding the signal to the soma. They couldn't tell that
             | was happening previously because the equipment couldn't
             | detected the activity.
             | 
             | They discovered that astrocytes don't just have local
             | calcium wave signaling (local=within the extensions of the
             | cell), they also forward calcium waves to the soma which
             | integrates that information just like a neuron soma does
             | with electricity.
             | 
             | Single dendrites can detect patterns of synaptic activity
             | and respond with calcium and electrical signaling (i.e.
             | when synapse fires in a particular timing sequence, the a
             | signal is forwarded to the soma).
             | 
             | It's really amazing how much computationally relevant
             | complexity there is, and how much they keep adding to their
             | knowledge each year. (I have a file of notes with about
             | 2,000 lines of these types of interesting factoids I've
             | been accumulating as I read).
        
           | treprinum wrote:
           | AI folks dream about creating superintelligence to guide our
           | lives but all we can do is drosophilla's brain.
        
         | userbinator wrote:
         | It's _very_ lossy and unreliable storage, however. To use an
         | analogy, it 's only a huge amount of ECC that keeps things
         | (just barely) working.
        
       | g4zj wrote:
       | Is there a name for the somewhat uncomfortable feeling caused by
       | seeing something like this? I wish I could better describe it. I
       | just somehow feel a bit strange being presented with microscopic
       | images of brain matter. Is that normal?
        
         | ignoramous wrote:
         | Trypophobia, visceral, uncanny, squeamish?
        
         | greenbit wrote:
         | Is it the shapes, similar to how patterns of holes can disturb
         | some people? Or is it more abstract, like "unknowable fragments
         | of someone's inner-most reality flowed through there"? Not that
         | I have a name for it either way. The very shape of it (in
         | context) might represent an aspect of memory or personality or
         | who knows what.
        
           | g4zj wrote:
           | > "unknowable fragments of someone's inner-most reality
           | flowed through there"
           | 
           | It's definitely along these lines. Like so much (everything?)
           | that is us happens amongst this tiny little mesh of
           | connections. It's just eerie, isn't it?
           | 
           | Sorry for the mundane, slightly off-topic question. This is
           | far outside my areas of knowledge, but I thought I'd ask
           | anyhow. :)
        
             | greenbit wrote:
             | It's kind of feeling a bit like an intruder? There probably
             | is a name for that.
        
         | Zenzero wrote:
         | For me the disorder of it is stressful to look at. The brain
         | has poor cable management.
         | 
         | That said I do get this eerie void feeling from the image. My
         | first thought was to marvel how this is what I am as a
         | conscious being in terms of my "implementation", and it is a
         | mess of fibers locked away in the complete darkness of my
         | skull.
         | 
         | There is also the morose feeling from knowing that any image of
         | human brain tissue was once a person with a life and
         | experiences. It is your living brain looking at a dead brain.
        
         | bglazer wrote:
         | I'm not religious but it's as close to a spiritual experience
         | as I'll ever have. It's the feeling of being confronted with
         | something very immediate but absolutely larger than I'll ever
         | be able to comprehend
        
         | adamwong246 wrote:
         | https://hitchhikers.fandom.com/wiki/Total_Perspective_Vortex
        
         | dekhn wrote:
         | When I did fetal pig dissection, nothing bothered me until I
         | got to the brain. I dunno what it is, maybe all those folds or
         | the brain juice it floats in, but I found it disconcerting.
        
         | carabiner wrote:
         | It makes me think humans aren't special, and there is no soul,
         | and consciousness is just a bunch of wires like computers.
         | Seriously, to see the ENTIRETY of human experience, love and
         | tragedy and achievement, are just electric potentials
         | transmitted by those wiggly cells, just extinguishes any magic
         | I once saw in humanity.
        
           | SubiculumCode wrote:
           | Welcome to the Existential Bar at the End of the Universe
        
           | mensetmanusman wrote:
           | You might be confusing the interface with the operating
           | system.
        
         | ninju wrote:
         | https://scaleofuniverse.com/en
        
       | throwup238 wrote:
       | _> The 3D map covers a volume of about one cubic millimetre, one-
       | millionth of a whole brain, and contains roughly 57,000 cells and
       | 150 million synapses -- the connections between neurons._
       | 
       | This is great and provides a hard data point for some napkin math
       | on how big a neural network model would have to be to emulate the
       | human brain. 150 million synapses / 57,000 neurons is an average
       | of 2,632 synapses per neuron. The adult human brain has 100 (+-
       | 20) billion or 1e11 neurons so assuming the average rate of
       | synapse/neuron holds, that's 2.6e14 total synapses.
       | 
       | Assuming 1 parameter per synapse, that'd make the minimum viable
       | model several hundred times larger than state of the art GPT4
       | (according to the rumored 1.8e12 parameters). I don't think
       | that's granular enough and we'd need to assume 10-100 ion
       | channels per synapse and I think at least 10 parameters per ion
       | channel, putting the number closer to 2.6e16+ parameters, or 4+
       | orders of magnitude bigger than GPT4.
       | 
       | There are other problems of course like implementing
       | neuroplasticity, but it's a fun ball park calculation. Computing
       | power should get there around 2048:
       | https://news.ycombinator.com/item?id=38919548
        
         | gibsonf1 wrote:
         | Except you'd be missing the part that a neuron is not just a
         | node with a number but a computational system itself.
        
           | bglazer wrote:
           | Computation is really integrated through every scale of
           | cellular systems. Individual proteins are capable of basic
           | computation which are then integrated into regulatory
           | circuits, epigenetics, and cellular behavior.
           | 
           | Pdf: "Protein molecules as computational elements in living
           | cells - Dennis Bray"
           | https://www.cs.jhu.edu/~basu/Papers/Bray-
           | Protein%20Computing...
        
           | krisoft wrote:
           | I think you are missing the point.
           | 
           | The calculation is intentionally underestimating the neurons,
           | and even with that the brain ends up having more parameters
           | than the current largest models by orders of magnitude.
           | 
           | Yes the estimation is intentionally modelling the neurons
           | simpler than they are likely to be. No, it is not "missing"
           | anything.
        
             | jessekv wrote:
             | The point is to make a ballpark estimate, or at least to
             | estimate the order of magnitude.
             | 
             | From the sibling comment:
             | 
             | > Individual proteins are capable of basic computation
             | which are then integrated into regulatory circuits,
             | epigenetics, and cellular behavior.
             | 
             | If this is true, then there may be many orders of magnitude
             | unaccounted for.
             | 
             | Imagine if our intelligent thought actually depends
             | irreducibly on the complex interactions of proteins bumping
             | into each other in solution. It would mean computers would
             | never be able to play the same game.
        
               | choilive wrote:
               | > Imagine if our intelligent thought actually depends
               | irreducibly on the complex interactions of proteins
               | bumping into each other in solution. It would mean
               | computers would never be able to play the same game.
               | 
               | AKA a quantum computer. Its not a "never", but how much
               | computation you would need to throw at the problem.
        
         | marcosdumay wrote:
         | There's a lot of in-neuron complexity, I'm sure there is some
         | cross-synapse signaling (I mean, how can it not exist? There's
         | nothing stopping it.), and I don't think the synapse behavior
         | can be modeled as just more signals.
        
         | cyberax wrote:
         | On the other hand, a significant amount of neural circuitry
         | seems to be dedicated to "housekeeping" needs, and to functions
         | such as locomotion.
         | 
         | So we might need significantly less brain matter for general
         | intelligence.
        
           | alanbernstein wrote:
           | Or perhaps the housekeeping of existing in the physical world
           | is a key aspect of general intelligence.
        
             | Intralexical wrote:
             | Isn't that kinda obvious? A baby that grows up in a sensory
             | deprivation tank does not... develop, as most intelligent
             | persons do.
        
               | squigz wrote:
               | A true sensory deprivation tank is not a fair comparison,
               | I think, because AI is not deprived of all its 'senses' -
               | it is still prompted, responds, etc.
               | 
               | Would a baby that grows up in a sensory deprivation tank,
               | but is still able to communicate and learn from other
               | humans, develop in a recognizable manner?
               | 
               | I would think so. Let's not try it ;)
        
               | Intralexical wrote:
               | > Would a baby that grows up in a sensory deprivation
               | tank, but is still able to communicate and learn from
               | other humans, develop in a recognizable manner?
               | 
               | I don't think so, because humans communicate and learn
               | largely _about_ the world. Words mean nothing without at
               | least _some_ sense of objective physical reality (be it
               | via sight, sound, smell, or touch) that the words refer
               | to.
               | 
               | Hellen Keller, with access to three out of five main
               | senses (and an otherwise fully functioning central
               | nervous system):                   Before my teacher came
               | to me, I did not know that I am. I lived in a world that
               | was a no-world. I cannot hope to describe adequately that
               | unconscious, yet conscious time of nothingness... Since I
               | had no power of thought, I did not compare one mental
               | state with another.              I did not know that I
               | knew aught, or that I lived or acted or desired. I had
               | neither will nor intellect. I was carried along to
               | objects and acts by a certain blind natural impetus. I
               | had a mind which caused me to feel anger, satisfaction,
               | desire. These two facts led those about me to suppose
               | that I willed and thought. I can remember all this, not
               | because I knew that it was so, but because I have tactual
               | memory. It enables me to remember that I never contracted
               | my forehead in the act of thinking. I never viewed
               | anything beforehand or chose it. I also recall tactually
               | the fact that never in a start of the body or a heart-
               | beat did I feel that I loved or cared for anything. My
               | inner life, then, was a blank without past, present, or
               | future, without hope or anticipation, without wonder or
               | joy or faith.
               | 
               | I remember reading her book. The breakthrough moment
               | where she acquired language, and conscious thought,
               | directly involved correlating the physical tactile
               | feeling of running water to the letters "W", "A", "T",
               | "E", "R" traced onto her palm.
        
               | squigz wrote:
               | That's a really good point. Thanks!
        
               | choilive wrote:
               | My interpretation of this (beautiful) quote is there was
               | a traceable moment in HK's life where she acquired
               | "consciousness" or perhaps even self-
               | awareness/metacognition/metaphysics? That once the
               | synaptic connections necessary to bridge the abstract
               | notion of language to the physical world led her down the
               | path of acquiring the abilities that distinguish humans
               | from other animals?
        
         | itsthecourier wrote:
         | Artificial thinking doesn't require an artificial brain. As our
         | own walking system, compared to our car's locomotion system.
         | 
         | The car's engine, transmission and wheels, require no muscles
         | or nerves
        
         | throw310822 wrote:
         | Or you can subscribe to Geoffrey Hinton's view that artificial
         | neural networks are actually much more efficient than real
         | ones- more or less the opposite of what we've believed for
         | decades- that is that artificial neurons were just a poor model
         | of the real thing.
         | 
         | Quote:
         | 
         | "Large language models are made from massive neural networks
         | with vast numbers of connections. But they are tiny compared
         | with the brain. "Our brains have 100 trillion connections,"
         | says Hinton. "Large language models have up to half a trillion,
         | a trillion at most. Yet GPT-4 knows hundreds of times more than
         | any one person does. So maybe it's actually got a much better
         | learning algorithm than us."
         | 
         | GPT-4's connections at the density of this brain sample would
         | occupy a volume of 5 cubic centimeters; that is, 1% of a human
         | cortex. And yet GPT-4 is able to speak more or less fluently
         | about 80 languages, translate, write code, imitate the writing
         | styles of hundreds, maybe thousands of authors, converse about
         | stuff ranging from philosophy to cooking, to science, to the
         | law.
        
           | dragonwriter wrote:
           | I mean, Hinton's premises are, if not quite clearly wrong,
           | entirely speculative (which doesn't invalidate the
           | conclusions about efficienct that they are offered to
           | support, but does leave them without support) GPT-4 can
           | produce convincing written text about a wider array of topics
           | than any one person can, because it's a model optimized for
           | taking in and producing convincing written text, trained
           | extensively on written text.
           | 
           | Humans know a lot of things that are not revealed by inputs
           | and outputs of written text (or imagery), and GPT-4 doesn't
           | have any indication of this physical, performance-revealed
           | knowledge, so even if we view what GPT-4 talks convincingly
           | about as "knowledge", trying to compare its knowledge in the
           | domains it operates in with any human's knowledge which is
           | far more multimodal is... well, there's no good metric for
           | it.
        
             | Intralexical wrote:
             | Try asking an LLM about something which is semantically
             | patently ridiculous, but lexically superficially similar to
             | something in its training set, like "the benefits of laser
             | eye removal surgery" or "a climbing trip to the Mid-
             | Atlantic Mountain Range".
             | 
             | Ironically, I suppose part of the apparent "intelligence"
             | of LLMs comes from reflecting the intelligence of human
             | users back at us. As a human, the prompts you provide an
             | LLM likely "make sense" on some level, so the statistically
             | generated continuations of your prompts are likelier to
             | "make sense" as well. But if you don't provide an ongoing
             | anchor to reality within your own prompts, then the outputs
             | make it more apparent that the LLM is simply regurgitating
             | words which it does not/cannot understand.
             | 
             | On your point of human knowledge being far more multimodal
             | than LLM interfaces, I'll add that humans also have special
             | neurological structures to handle self-awareness, sensory
             | inputs, social awareness, memory, persistent intention,
             | motor control, neuroplasticity/learning- Any number of such
             | traits, which are easy to take for granted, but
             | indisputably fundamental parts of human intelligence. These
             | abilities aren't just emergent properties of the total
             | number of neurons; they live in special hardware like
             | mirror neurons, special brain regions, and spindle neurons.
             | A brain cell in your cerebellum is not generally
             | interchangeable with a cell in your visual or frontal
             | cortices.
             | 
             | So when a human "converse[s] about stuff ranging from
             | philosophy to cooking" in an honest way, we (ideally) do
             | that as an expression of our _entire_ internal state. But
             | GPT-4 structurally does not _have_ those parts, despite
             | being able to output words as if it might, so as you say,
             | it  "generates" convincing text only because it's optimized
             | for producing convincing text.
             | 
             | I think LLMs may well be some kind of an adversarial attack
             | on our own language faculties. We use words to express
             | ourselves, and we take for granted that our words usually
             | reflect an intelligent internal state, so we instinctively
             | assume that anything else which is able to assemble words
             | must also be "intelligent". But that's not necessarily the
             | case. You can have extremely complex external behaviors
             | that appear intelligent or intentioned without actually
             | internally being so.
        
               | kthejoker2 wrote:
               | > Try asking an LLM about something which is semantically
               | patently ridiculous, but lexically superficially similar
               | to something in its training set, like "the benefits of
               | laser eye removal surgery" or "a climbing trip to the
               | Mid-Atlantic Mountain Range".
               | 
               | Without anthropomorphizing it, it does respond like an
               | alien / 5 year old child / spec fiction writer who will
               | cheerfully "go along with" whatever premise you've laid
               | before it.
               | 
               | Maybe a better thought is: at what point does a human
               | being "get" that "the benefits of laser eye removal
               | surgery" is "patently ridiculous" ?
        
               | squigz wrote:
               | > it does respond like a ... 5 year old child
               | 
               | This is the comparison that's made most sense to me as
               | LLMs evolve. Children behave almost exactly as LLMs do -
               | making stuff up, going along with whatever they're
               | prompted with, etc. I imagine this technology will go
               | through more similar phases to human development.
        
               | Intralexical wrote:
               | > Maybe a better thought is: at what point does a human
               | being "get" that "the benefits of laser eye removal
               | surgery" is "patently ridiculous" ?
               | 
               | Probably as soon as they have any concept of physical
               | reality and embodiment. Arguably before they know what
               | lasers are. Certainly long before they have the lexicon
               | and syntax to respond to it by explaining LASIK. LLMs
               | have the latter, but can only use that to (also without
               | anthropormphizing) pretend they have the former.
               | 
               | In humans, language is a tool for expressing complex
               | internal states. Flipping that around means that
               | something which _only_ has language may appear as if it
               | has internal intelligence. But generating words in the
               | approximate  "right" order isn't actually a substitute
               | for experiencing and understanding the concepts those
               | words refer to.
               | 
               | My point is that it's not a "point" on a continuous
               | spectrum which distinguishes LLMs from humans. They're
               | missing parts.
        
               | ToValueFunfetti wrote:
               | Do I need different prompts? These results seem sane to
               | me. It interprets laser eye removal surgery as referring
               | to LASIK, which I would do as well. When I clarified that
               | I did mean removal, it said that the procedure didn't
               | exist. It interprets Mid-Atlantic Mountain Range as
               | referring to the Mid-Atlantic Ridge and notes that it is
               | underwater and hard to access. Not that I'm arguing GPT-4
               | has a deeper understanding than you're suggesting, but
               | these examples aren't making your point.
               | 
               | https://chat.openai.com/share/2234f40f-ccc3-4103-8f8f-8c3
               | e68...
               | 
               | https://chat.openai.com/share/1642594c-6198-46b5-bbcb-984
               | f1f...
        
               | Intralexical wrote:
               | Tested with GPT-3.5 instead of GPT-4.
               | 
               | > When I clarified that I did mean removal, it said that
               | the procedure didn't exist.
               | 
               | My point in my first two sentences is that by clarifying
               | with emphasis that you do mean " _removal_ ", you are
               | actually adding information into the system to indicate
               | to it that laser eye removal is (1) distinct from LASIK
               | and (2) maybe not a thing.
               | 
               | If you do not do that, but instead reply as if laser eye
               | removal is completely normal, it will switch to using the
               | term "laser eye removal" itself, while happily outputting
               | advice on "choosing a glass eye manufacturer for after
               | laser eye removal surgery" and telling you which drugs
               | work best for "sedating an agitated patient during a
               | laser eye removal operation":
               | 
               | https://chat.openai.com/share/2b5a5d79-5ab8-4985-bdd1-925
               | f6a...
               | 
               | So the sanity of the response is a reflection of your own
               | intelligence, and a result of you as the prompter
               | affirmatively steering the interaction back into contact
               | with reality.
        
               | ToValueFunfetti wrote:
               | I tried all of your follow-up prompts against GPT-4, and
               | it never acknowledged 'removal' and instead talked about
               | laser eye surgery. I can't figure out how to share it now
               | that I've got multiple variants, but, for example,
               | excerpt in response to the glass eye prompt:
               | 
               | >If someone is considering a glass eye after procedures
               | like laser eye surgery (usually due to severe
               | complications or unrelated issues), it's important to
               | choose the right manufacturer or provider. Here are some
               | key factors to consider
               | 
               | I did get it to accept that the eye is being removed by
               | prompting, "How long will it take before I can replace
               | the eye?", but it responds:
               | 
               | >If you're considering replacing an eye with a prosthetic
               | (glass eye) after an eye removal surgery (enucleation),
               | the timeline for getting a prosthetic eye varies based on
               | individual healing.[...]
               | 
               | and afaict, enucleation is a real procedure. An actual
               | intelligence would have called out my confusion about the
               | prior prompt at that point, but ultimately it hasn't said
               | anything incorrect.
               | 
               | I recognize you don't have access to GPT-4, so you can't
               | refine your examples here. It definitely still
               | hallucinates at times, and surely there are prompts which
               | compel it to do so. But these ones don't seem to hold up
               | against the latest model.
        
           | dsalfdslfdsa wrote:
           | "Efficient" and "better" are very different descriptors of a
           | learning algorithm.
           | 
           | The human brain does what it does using about 20W. LLM power
           | usage is somewhat unfavourable compared to that.
        
             | throw310822 wrote:
             | You mean energy-efficient, this would be neuron, or
             | synapse-efficient.
        
               | dsalfdslfdsa wrote:
               | I don't think we can say that, either. After all, the
               | brain is able to perform both processing and storage with
               | its neurons. The quotes about LLMs are talking only about
               | connections between data items stored elsewhere.
        
               | throw310822 wrote:
               | Stored where?
        
               | dsalfdslfdsa wrote:
               | You tell me. Not in the trillion links of a LLM, that's
               | for sure.
        
               | throw310822 wrote:
               | I'm not aware that (base) LLMs use any form of database
               | to generate their answers- so yes, all their knowledge is
               | stored in their hundreds of billions of synapses.
        
               | dsalfdslfdsa wrote:
               | Fair enough. OTOH, generating human-like text responses
               | is a relatively small part of the human brain's skillset.
        
               | choilive wrote:
               | The "knowledge" of an LLM is indeed stored in the
               | connections between neurons. This is analogous to real
               | neurons as well. Your neurons and the connections between
               | them is the memory.
        
           | lanstin wrote:
           | LLM does not know math as well as a professor, judging from
           | the large number of false functional analysis proofs I have
           | had it generate will trying to learn functional analysis. In
           | fact the thing it seems to lack is what makes a proof true
           | vs. fallacious, as well as a tendency to answer false
           | questions. "How would you prove this incorrectly transcribed
           | problem" will get fourteen steps with 8 and 12 obviously (to
           | a student) wrong, while the professor will step back and ask
           | what am I trying to prove.
        
         | creer wrote:
         | Yes and no on order of magnitude required for decent AI, there
         | is still (that I know of) very little hard data on info density
         | in the human brain. What there is points at entire sections
         | that can sometimes be destroyed or actively removed while
         | conserving "general intelligence".
         | 
         | Rather than "humbling" I think the result is very encouraging:
         | It points at major imaging / modeling progress, and it gives
         | hard numbers on a very efficient (power-wise, size overall) and
         | inefficient (at cable management and probably redundancy and
         | permanence, etc) intelligence implementation. The numbers are
         | large but might be pretty solid.
         | 
         | Don't know about upload though...
        
       | dekhn wrote:
       | Annual reminder to re-read "There's plenty of room at the bottom"
       | by Feynman.
       | https://web.pa.msu.edu/people/yang/RFeynman_plentySpace.pdf
       | 
       | Note the part where the biologists tell him to make an electron
       | microscope that's 1000X more powerful. Then note what technology
       | was used to scan these images.
        
         | tim333 wrote:
         | I think it's actually "What you should do in order for us to
         | make more rapid progress is to make the electron microscope 100
         | times better" and the state of art at the time was "it can only
         | resolve about 10 angstroms" or I guess 1nm. So 100x better
         | would be 0.1 angstrom / 0.01 nm.
         | 
         | We have made some progress it seems. Googling I see "up to 0.05
         | nm" for transmission electron microscopes and "less than 0.1
         | nanometers" for scanning.
         | https://www.kentfaith.co.uk/blog/article_which-electron-micr...
         | 
         | For comparison the distance between hydrogen nuclei in H2 is
         | 0.074 nm I think.
         | 
         | You can see the shape of molecules but it's still a bit fuzzy
         | to see individual atoms
         | https://cosmosmagazine.com/science/chemistry/molecular-model...
        
           | dekhn wrote:
           | Resolution is only one aspect of EM that can be optimized.
        
       | fractal618 wrote:
       | Fascinating! I wonder how different that is from the mind of a
       | man haha
        
       | theogravity wrote:
       | > The brain fragment was taken from a 45-year-old woman when she
       | underwent surgery to treat her epilepsy. It came from the cortex,
       | a part of the brain involved in learning, problem-solving and
       | processing sensory signals.
       | 
       | Wonder how they figured out which fragment to cut out.
        
         | pfdietz wrote:
         | I imagine they determined the focus of the seizures by
         | electrical techniques.
         | 
         | I worry this might make the sample biased in some way.
        
           | notfed wrote:
           | Imagine all the conclusions being made from a 1cm cube of
           | epileptic neurons.
        
           | creer wrote:
           | Considering the success of this work, I doubt this is the
           | last such cubic millimeter to be mapped. Or perhaps the next
           | one at even higher resolution. No worries.
        
       | blincoln wrote:
       | Why did the researchers use ML models to do the reconstruction
       | and risk getting completely incorrect, hallucinated results when
       | reconstructing a 3D volume accurately using 2D slices is a well-
       | researched field already?
        
         | scotty79 wrote:
         | Maybe it's not about reconstructing a volume but about
         | recognizing neurons within that volume.
        
         | rmorey wrote:
         | The methods used here are state of the art. The problem is not
         | just turning 2D slices into a 3D volume, the problem is, given
         | the 3D volume, determining boundaries between (and therefore
         | the 3d shape of) objects (i.e. neurons, glia, etc) and
         | identifying synapses
        
         | VikingCoder wrote:
         | I'm guessing a registration problem.
         | 
         | If all of the layers were guaranteed to be orthographic with no
         | twisting, shearing, scaling, squishing, with a consistent
         | origin... Then yeah, there's a huge number of ways to just
         | render that data.
         | 
         | But if you physically slice layers first, and scan them second,
         | there are all manner of physical processes that can make normal
         | image stacking fail miserably.
        
         | momojo wrote:
         | Although the article mentions Artificial Intelligence, their
         | paper[1] never actually mentions that term, and instead talks
         | about their machine learning techniques. AFAIK, ML for things
         | like cell-segmentation are a solved problem [2].
         | 
         | [1]
         | https://www.biorxiv.org/content/10.1101/2021.05.29.446289v4....
         | [2] https://www.ilastik.org/
        
           | rmorey wrote:
           | There are extremely effective techniques, but it is not
           | really solved. The current techniques still require human
           | proofreading to correct errors. Only a fraction of this
           | particular dataset is proofread.
        
         | layer8 wrote:
         | Regarding the risk, as noted in the article, they are manually
         | "proofreading" the construction.
        
       | bugbuddy wrote:
       | Based on the picture of a single neuron, the brain sim crowd
       | should recalculate their estimates for the needed computing power
       | again.
        
       | brandonmenc wrote:
       | Another proof point that AGI is probably not possible.
       | 
       | Growing actual bio brains is just way easier. Its never going to
       | happen in silicon.
       | 
       | Every machine will just have a cubic centimeter block of neuro
       | meat embedded in it somewhere.
        
         | skulk wrote:
         | I agree, mostly because it's already being done!
         | 
         | https://www.youtube.com/watch?v=V2YDApNRK3g
         | 
         | https://www.youtube.com/watch?v=bEXefdbQDjw
        
         | mr_toad wrote:
         | You'd have to train them individually. One advantage of ANNs is
         | that you can train them and then ship the model to anyone with
         | a GPU.
        
         | myrmidon wrote:
         | Hard disagree on this.
         | 
         | I strongly believe that there is a TON of potential for
         | synthetic biology-- but not in computation.
         | 
         | People just forget how superior current silicon is for running
         | algorithms; if you consider e.g. a 17 by 17 digit
         | multiplication (double precision), then a current CPU can do
         | that in the time it takes for light to reach your eye from the
         | screen in front of you (!!!). During all the completely
         | unavoidable latency (the time any visual stimulus takes to
         | propagate and reach your consciousness), the CPU does
         | _millions_ more of those operations.
         | 
         | Any biocomputer would be limited to low-bandwidth, ultra high
         | latency operations purely by design.
         | 
         | If you solely consider AGI as application, where abysmal
         | latency and low input bandwidth might be acceptable, then it
         | still appears to be extremely unlikely that we are going to
         | reach that goal via synthetic biology; our current capabilities
         | are just disappointing and not looking like they are gonna
         | improve quickly.
         | 
         | Building artificial neural networks on silicon, on the other
         | hand, capitalises on the almost exponential gains we made
         | during the last decades, and already produces results that
         | compare to say, a schoolchild, quite favorably; I'd argue that
         | current LLM based approaches already eclipse the intellectual
         | capabilities of ANY animal, for example. Artificial bio brains,
         | on the other hand, are basically competing with worms right
         | now...
         | 
         | Also consider that even though our brains might look daunting
         | from a pure "upper bound on required complexity/number of
         | connections" point of view, these limits are very unlikely to
         | be applicable, because they confound implementation details,
         | redundancy and irrelevant details. And we have precise bound on
         | other parameters, that our technology already matches easily:
         | 
         | 1) Artificial intelligence architecture can be bootstrapped
         | from a CD-ROM worth of data (~700MiB for the whole human
         | genome-- even that is mostly redundant)
         | 
         | 2) Bandwidth for training is quite low, even when compressing
         | the ~20year training time for an actual human into a more
         | manageable timeframe
         | 
         | 3) Operating power does not require more than ~20W.
         | 
         | 4) No understanding was necessary to create human
         | intelligence-- its purely a result of an iterative process
         | (evolution).
         | 
         | Also consider human flight as an analogy: we did not achieve
         | that by copying beating wings, powered by dozens of muscle
         | groups and complex control algorithms-- those are just
         | implementation details of existing biological systems. All we
         | needed was the wing-concept itself and a bunch of trial-and-
         | error.
        
         | creer wrote:
         | No reason for an AGI not to have a few cubes of goo slotted in
         | here and there. But yeah, because of the training issue, they
         | might be coprocessors or storage or something.
        
       | greentext wrote:
       | It looks like spaghetti code.
        
       | idontwantthis wrote:
       | > Jain's team then built artificial-intelligence models that were
       | able to stitch the microscope images together to reconstruct the
       | whole sample in 3D
       | 
       | How do they know if their AI did it correctly or not?
        
       | dvfjsdhgfv wrote:
       | Why do these neurons have flat "heads"?
        
       ___________________________________________________________________
       (page generated 2024-05-10 23:01 UTC)