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Cubic millimetre of brain mapped at nanoscale resolution

nature.com

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Re: Cubic millimetre of brain mapped at nanoscale resolution

#141

Post by thealig »

a_wild_dandan wrote: post #112
Intralexical wrote: post #74

Earlier quoted context omitted.

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…

Like humans, multi-modal frontier LLMs will ignore "removal" as an impertinent typo, or highlight it. This, like everything else in the comment, is either easily debunked (e.g. try it, read the lit. on LLM extrapolation), or so nebulous and handwavy as to be functionally meaningless. We need an FAQ to redirect "statistical parrot" people to, saving words responding to these worn out LLM misconceptions. Maybe I should…

THe way current empirical models in ML are evaluated and tested ( benchmark datasets) tell you very little to nothing about cognition and intelligence. Mainly because as you hinted , there doesn't seem to be a convincing and watertight benchmark or model of cognition. LLMs or multi-modal LLMs demonstrating impressive performance on a range of tasks is interesting from certain standpoints.

Human perception of such models is frankly not a reliable measure at all as far as gauging capabilities is concerned. Until there's more progess on the nueroscience/computer science (and an intersection of fields probably) and better understanding of the nature of intelligence, this is likely going to remain an open question.

Re: Cubic millimetre of brain mapped at nanoscale resolution

#142

Post by ein0p »

As important and impressive a result as this is, I am reminded of the cornerstone problem of neuroscience, which goes something like this: if we knew next to nothing about processors but could attach electrodes to the die, would we be able to figure out how processors execute programs and what those programs do, in detail, just from the measurements alone? And now scale that up several orders of magnitude and introduce sensitivity to timing of arrival for signals, and you got the brain. Likewise ok, you have petabytes of data now, but will we ever get closer to understanding, for example, how cognition works? It was a bit of a shock for me when I found out (while taking an introductory comp neuroscience course) that we simply do not have tractable math to model more than a handful neurons in time domain. And they do actually operate in time domain - timings are important for Hebbian learning, and there’s no global “clock” - all that the brain does is a continuous process.

Re: Cubic millimetre of brain mapped at nanoscale resolution

#143

Post by thfuran »

myrmidon wrote: post #88
brandonmenc wrote: post #54

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.

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 unav…

>Artificial intelligence architecture can be bootstrapped from a CD-ROM worth of data (~700MiB for the whole human genome-- even that is mostly redundant)

Are you counting epigenetic factors in that? They're heritable.

Re: Cubic millimetre of brain mapped at nanoscale resolution

#144

Post by lostlogin »

sdenton4 wrote: post #114
Terr_ wrote: post #68

Earlier quoted context omitted.

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…

Humans are an n=1 example, is my point. And there's no direct competition between bird brain architecture and mammalian brain architecture, so there's no reason for one architecture to 'win' over the other - they may both be interesting local maxima, which we have no ability to directly compare. Human brains might not be all that efficient; for example, if the competitive edge for primate brains is distinct enough, t…

> And there's no direct competition between bird brain architecture and mammalian brain architecture

By and large It’s not direct competition but we are stamping our species at an alarming rate and birds are taking a hammering.

Re: Cubic millimetre of brain mapped at nanoscale resolution

#145

Post by golergka »

ein0p wrote: post #142

As important and impressive a result as this is, I am reminded of the cornerstone problem of neuroscience, which goes something like this: if we knew next to nothing about processors but could attach electrodes to the die, would we be able to figure out how processors execute programs and what those programs do, in detail, just from the measurements alone? And now scale that up several orders of magnitude and introdu…

Particle physics works in a similar way, but instead of attaching electrodes, you shoot at them with guns and then analyze trajectories of the fragments.

Re: Cubic millimetre of brain mapped at nanoscale resolution

#146

Post by causal »

a_wild_dandan wrote: post #111
throw310822 wrote: post #78

Earlier quoted context omitted.

You mean energy-efficient, this would be neuron, or synapse-efficient.

Also, these two networks achieves vastly different results, per watt consumed. A NN creates a painting in 4s on my M2 MacBook; an artist in 4 hours. Are their used joules equivalent? How many humans would it take to simulate MacOS? Horsepower comparisons here are nuanced and fatally tricky!

Humans aren't able to project an image from their neurons onto a disk like ANNs can, if they could it would also be very fast. That 4 hour estimate includes all the mechanical problems of manipulating paint.

Re: Cubic millimetre of brain mapped at nanoscale resolution

#147

Post by causal »

throw310822 wrote: post #55
throwup238 wrote: post #12

> 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 adu…

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…

Hinton is way off IMO. Amount of examples needed to teach language to an LLM is many orders of magnitude more than humans require. Not to mention power consumption and inelasticity.

Re: Cubic millimetre of brain mapped at nanoscale resolution

#149

Post by spacetimeuser5 »

ein0p wrote: post #142

As important and impressive a result as this is, I am reminded of the cornerstone problem of neuroscience, which goes something like this: if we knew next to nothing about processors but could attach electrodes to the die, would we be able to figure out how processors execute programs and what those programs do, in detail, just from the measurements alone? And now scale that up several orders of magnitude and introdu…

>> The sample was immersed in preservatives and stained with heavy metals to make the cells easier to see.

Try experimenting with immersing your brain in preservatives and staining with heavy metals to see how would you be able to write the comment similar to the above.

No wonder that monkey methods continue to unveil monkey cognition.

Re: Cubic millimetre of brain mapped at nanoscale resolution

#150

Post by spacetimeuser5 »

golergka wrote: post #145
ein0p wrote: post #142

As important and impressive a result as this is, I am reminded of the cornerstone problem of neuroscience, which goes something like this: if we knew next to nothing about processors but could attach electrodes to the die, would we be able to figure out how processors execute programs and what those programs do, in detail, just from the measurements alone? And now scale that up several orders of magnitude and introdu…

Particle physics works in a similar way, but instead of attaching electrodes, you shoot at them with guns and then analyze trajectories of the fragments.

The cheap monkey headset works in a similar way: monkeys just essentially continue to analyze trajectories of medieval cannon balls in the LHC and to count potatoes in the form of bytes.
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