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A single memory is stored across many connected brain regions

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Re: A single memory is stored across many connected brain regions

#12
post #9

Their study looks not specifically at a storage site, but that along with the sites for processing a new memory for storage, and processes for recalling a memory from storage. When you see something, that visual input is processed in a certain area that, IIRC, is the same area that is fired when recalling a visual memory. When a memory is recalled, it is processed by the same regions that interpreted it initially upo…

I remember telling some people that this is how it works back in 2003 or so.

I read a book that said the architecture of the brain was like a polyhedron where the vertexes represented different processing modes (visual, auditory, linguistic, emotional, ...) and that bundles of fibers that go down into the white matter and connect processing areas in the grey matter of the cortex.

If you think about a "dog", those connecting fibers activate images of the dog, the sounds the dog makes, the motor program to pet the dog, the feeling of the fur, etc...

Re: A single memory is stored across many connected brain regions

#14
post #4

Disclaimer: I know brain != deep learning neural nets. We do have a lot of evidence that the brain is _some_ type of network with analogue qualities. Does it even make sense to say that a memory is stored somewhere in a specific region, if the brain is an analogue network? A property of analogue networks is that all nodes make a contribution, even if many of the contributions are infinitesimally small. The equivalent…

I don't have any clear answers for you, but one interesting note here is that a recent paper showed that it took a deep neural net to be able to simulate the "IO" of a single cortical neuron. So that should give you some idea of the complexity involved compared to artificial neural nets, Re: your disclaimer.

https://www.sciencedirect.com/science/article/abs/pii/S08966...

Re: A single memory is stored across many connected brain regions

#15
post #9

Their study looks not specifically at a storage site, but that along with the sites for processing a new memory for storage, and processes for recalling a memory from storage. When you see something, that visual input is processed in a certain area that, IIRC, is the same area that is fired when recalling a visual memory. When a memory is recalled, it is processed by the same regions that interpreted it initially upo…

I remember telling some people that this is how it works back in 2003 or so. I read a book that said the architecture of the brain was like a polyhedron where the vertexes represented different processing modes (visual, auditory, linguistic, emotional, ...) and that bundles of fibers that go down into the white matter and connect processing areas in the grey matter of the cortex. If you think about a "dog", those con…

Agree. Our experience of the world isn't a screen painted with what the world looks like. But instead is a collection of affordances and expectations.

Have you ever picked up an empty milk jug and yanked it super fast? Did you choose to yank it. Or did the program called pick up heavy milk jug run instead of empty milk jug. Feeling the confusion over how light the jug was causes the program "confusion" to run to help you look for an explanation about why this object is so different from what you expected.

The reasoning program creates the feeling of resolution once you arrive at, "I believed it was full but it wasn't", but prior to that resolution, if you really pay attention, you are just standing there for a moment puzzled about why your arm is moving so fast.

Re: A single memory is stored across many connected brain regions

#16
post #3

Earlier quoted context omitted.

Do we actually know how the memory is coded specifically? Is it a specific firing of a neuron (or a neuron ensemble), is it the specific answer you get from exciting the neuron(s)? Or any combination thereof?

> Do we actually know how the memory is coded specifically? No, we don't.

My opinion is that its the evolutionary process of chemical organisation in an environment. We see gene differences but we also see many parallels in other species. Unlock every effect a chemical has and you can unlock consciousness.

Re: A single memory is stored across many connected brain regions

#18
post #4

Disclaimer: I know brain != deep learning neural nets. We do have a lot of evidence that the brain is _some_ type of network with analogue qualities. Does it even make sense to say that a memory is stored somewhere in a specific region, if the brain is an analogue network? A property of analogue networks is that all nodes make a contribution, even if many of the contributions are infinitesimally small. The equivalent…

Some types of artificial neural networks are biologically plausible. The layered structure of the cerebral cortex reflects the layers of an artificial network.

Re: A single memory is stored across many connected brain regions

#19
post #2

I've never really loved contextual fear conditioning as the default for "memory". Another way of describing this result is that "even a mild trauma scars the entire brain." In all seriousness, though, I'd say that there's a broad dispute in the field between those that believe that memory involves dynamic neural activity involving a multiplexed circuit of neurons that encode many different memories and those (current…

I'll look into the why a group believes memories are associated with individual neurons as my personal intuition (edit: and this article as well) tells me the opposite.

For example, if I try to remember the name of an actor, I can have hints from my brain telling me "their name starts with an _m_" and "it's a man who played in a movie from the 90's", etc. A memory feels like it cannot be isolated, it always feels like a composition of different elements that, when put together, describe one thing, or many. The more elements (in that case maybe single neurons, or very small group of neurons) are activated the clearer the memory. A Venn diagram of sort where the overlap gets smaller and smaller. This would explain the "this makes me think of…" process, since a certain number of these elements from one memory will overlap with the elements of another one.

This is completely personal and completely unscientific. And maybe this is neuroscience 101… In that case sorry for stating the obvious.

Re: A single memory is stored across many connected brain regions

#20
post #4

Disclaimer: I know brain != deep learning neural nets. We do have a lot of evidence that the brain is _some_ type of network with analogue qualities. Does it even make sense to say that a memory is stored somewhere in a specific region, if the brain is an analogue network? A property of analogue networks is that all nodes make a contribution, even if many of the contributions are infinitesimally small. The equivalent…

Some types of artificial neural networks are biologically plausible. The layered structure of the cerebral cortex reflects the layers of an artificial network.

The difference being of course that as opposed to a mere 16 bit parameter, a cortical neuron is a complex "nanomechanical" machine capable of significant computation in its own right.
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