If they freeze the vesicles that deliver transmitters and make them analyzable, you've got all the information you need. In terms of a modern ANN, it's the connections (axons) and the weights (transmitters/receptors in tandem).
That said, this article doesn't get to the point in the free section. How are they collecting the information? Slicing is inherently destructive. Someone's got to manufacture an entirely novel imaging modality. Perhaps they could scan millimeters ahead of the slice at a resolution high enough to image receptors. Not possible currently.
Take a gander at the OpenWorm project. It's a great example of how simple neuronal activity is (given details like the connections, number of receptors, and transmitter infrastructure). SOTA models of neuronal activity are simple enough for problem sets in undergraduate biomedical engineering programs.
Sure, to your point, we don't know. But the worm above (nematode) swims and seeks food when dropped into a physics engine.
My main point is that the scale of the human brain is well beyond the capabilities of modern imaging modalities, and it will likely remain so indefinitely. Fascicles we can image, individual axons we cannot. I guess, theoretically, we'll eventually be able to (but it's not relevant to us or any of our remote descendants).
> But the worm above (nematode) swims and seeks food when dropped into a physics engine.
Nematode worms have an oxytocin analogue called nematocin that is known to influence learning and social behaviors like mating. As far as I can find, the project doesn't account for this, or only minimally, but aims to in the future.
It's not surprising that immediate short-term behaviors like movement depend mostly on the faster signaling of the connectome. But since we know of other mechanisms that most definitely influence the connectome's behavior, and we know we don't account for those at the moment, it is not accurate to say that the connectome is "all the information you need".
I agree that mapping the connectome of the human brain is impractical to the point of impossibility. But even if we could, the resulting "circuit diagram" would not capture all the details needed to fully replicate human cognition. Aspects of it, sure. Maybe even enough to make it do useful tasks for EvilCorp LLC while being prodded with virtual sticks and carrots. But it would be incomplete.
I saw a putative 3D animation of a fly whose brain had been digitized and then run in a simulation. It buzzed around, sipped food it had found on the ground, even rubbed its forelegs together as flies do. A true Dixie Flyline. We live in strange times...
There's research on the translation process where cells are basically flash-frozen (to avoid water crystals), then imaged with cryoelectronmicroscopy / AFM etc. where they image the translation process (RNA to protein) in order to get snapshots and get a better understanding of how the folding proceeds and is aided.
If we can image sub-cellular features, what makes you believe we can't trace all the axons, dendrites and the synapses?
It seems more like a question of how to do it cost effectively at scale, not so much a question of "can we or not?".
> If they freeze the vesicles that deliver transmitters and make them analyzable, you've got all the information you need. In terms of a modern ANN, it's the connections (axons) and the weights (transmitters/receptors in tandem).
This is exactly what I’m doubting, how can you be so sure?
Yeah but it wasn’t though. I found your answer unconvincing. I suppose “we don’t know” is an answer but that is nothing like “we have all the information we need”
Am I right in thinking that even if you had all of the connections and weights mapped out for a brain, the specifics of synaptic plasticity are still pretty poorly understood?
What is the state of the art in regards to how neurons learn over time? Do existing neuron models account for that? Being trapped, unable to learn anything, sounds terrible.
It is my understanding that for the animals where we have a simulation of the full connectome the behavior you see approximates the real behavior reasonably well, so maybe the jury is still out as to whether it is sufficient or not.
How about that few want one artist’s particular style reproduced, instead they want what they are vaguely seeing in their head produced from a cacophony of styles
It’s not meaningless; it’s a way for them to immediately prove that the person speaking has been intimidated enough by them to acquiesce to this absurdity. If they don’t, they can be punished just for refusing. If they do, they’re already back on their heels proving their willingness to cave on anything else.
No, the major healthcare employers are trying to adjust their staff sizes immediately to avoid later crisis caused by this draconian hack and slash approach to federal funding.
If that's how you perceive child-rearing property of communities that's a shame. It takes a village to raise a child. As the african proverb goes the child that doesn't feel warmth will burn a village down to feel it.
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