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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

#151
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.

> Try… immersing your brain in preservatives and staining with heavy metals

I think we all do every day

Re: Cubic millimetre of brain mapped at nanoscale resolution

#152
post #132

Earlier quoted context omitted.

Would be interesting to see what their wafer yield is. Like, are they more or less prone to mental disease.

all the crows can tell i'm crazy, but i've never met an insane crow.

I dunno anyone who screams “Caw! CAW!”, raids garbage and poops in the street all day would probably be put in a mental institution. (Or just move to San Francisco.)

Re: Cubic millimetre of brain mapped at nanoscale resolution

#153

Earlier quoted context omitted.

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?

The electrical signals in brain are chemical reactions, not conductivity like a metal wire. They are slow! Synaptic junctions are a huge number of indirect chemical cascades, not a direct electrical connection, they are even slower! So brain morphology and connectome has a massive impact on what can be computed. Human twitch responses are done by cerebellum, not cerebrum. It's faster, but you can't do philosophy with…

>The electrical signals in brain are chemical reactions, not conductivity like a metal wire.

Nerve signals are both chemical reactions and electrical impulses like metal wire. Electrical impulses are sent along the fat layer by ions Potassium , Calcium, Sodium etc.

Twitch responses are actually done in spinal cord. The signals are short circuited all along the spine and return back to muscle without touching the brain ever.

Re: Cubic millimetre of brain mapped at nanoscale resolution

#154

Earlier quoted context omitted.

>> 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.

> Try… immersing your brain in preservatives and staining with heavy metals I think we all do every day

Try using the protocols and doses from the original article.

Re: Cubic millimetre of brain mapped at nanoscale resolution

#155
post #147

Earlier quoted context omitted.

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.

I think that what Hinton is saying is that, in his opinion, if you fed a 1/100th of a human cortex with the amount of data that is used to train llms, you wouldn't get a thing that can speak in 80 different languages about a gigantic number of subjects, but (I'm interpreting here..) about ten of grams of fried, fuming organic matter.

This doesn't mean that an entire human brain doesn't surpass llms in many different ways, only that artificial neural networks appear to be able to absorb and process more information per neuron than we do.

Re: Cubic millimetre of brain mapped at nanoscale resolution

#156
After reading through all comments as of 2024/05/11 I (as a professor at some major university) am quite surprised that not one single comment has asked the obvious question (instead of dishing out loads of (partial) "textbook knowledge" about brain functions, the difference between mammals and birds, AI and LLM etc.), which would be: what do all those strange structures and objects do which we know nothing about whatsoever? Have a look:

https://h01-release.storage.googleapis.com/gallery.html

I count seven.

Re: Cubic millimetre of brain mapped at nanoscale resolution

#157
post #132

Earlier quoted context omitted.

all the crows can tell i'm crazy, but i've never met an insane crow.

I dunno anyone who screams “Caw! CAW!”, raids garbage and poops in the street all day would probably be put in a mental institution. (Or just move to San Francisco.)

You say that, but a world with more crows than tax payers honestly sounds kind of serene.

Re: Cubic millimetre of brain mapped at nanoscale resolution

#158
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…

Right. The arguments for the study of A.I. were that you will not discover the principles of flight by looking at a birds feather under an electron microscope.

It’s fascinating, but we aren’t going to understand intelligence this way. Emergent phenomenon are part of complexity theory, and we don’t have any maths for it. Our ignorance in this space is large.

When I was young, I remember a common refrain being “will a brain ever be able to understand itself?”. Perhaps not, but the drive towards understanding is still a worthy goal in my opinion. We need to make some breakthroughs in the study of complexity theory.

Re: Cubic millimetre of brain mapped at nanoscale resolution

#159

Earlier quoted context omitted.

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?

And here I was wondering if there were heat issues in a crow brain.

Throw some thermal paste on those neurons and they do just fine

Re: Cubic millimetre of brain mapped at nanoscale resolution

#160
post #9
post #2

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...

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?

Can a hand grasp itself?
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