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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

#21

Post by causi »

cells activated by naturally recalling the unpleasant memory

The maps highlighted many regions expected to participate in memory, but also many that were not

This feels like a study from decades ago, as if it were done in complete ignorance of the fact brains store event descriptors and entity descriptors separately. "Program data" and "character data" to use an analogy. Of course that sort of unselective "memory make marker go brr" analysis will show up all over the place because the brain is touching a dozen or more different types of data at once. If you want usefully specific results you have to use usefully specific methods.

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

#26

Post by mattkrause »

mtlmtlmtlmtl wrote: post #10
davidktr wrote: 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?

IANA neuroscientist, so please correct me if I'm wrong or oversimplifying: IIRC one of the main cellular mechanisms thought to underlie memory is LTP(Long Term Potentiation) in glutamatergic neurons. There are different kinds of glutamate receptors, but we're interested in the two subtypes of ion channel based(ionotropic) Glut receptors, AMPA and NMDA. AMPA is sort of your main receptor for propagating signals: it's…

This is all true (as far as we know), but it's tricky to suss how exactly how this works in a living brain.

It's relatively easy to induce spike-timing dependent plasticity in vitro, where the background activity is low and the experimenter has almost total control over the pre/post-synaptic neurons' activity. However, in vivo neurons are often bombarded with input from thousands of synaptic partners, breaking the clear correspondence that underlies a lot of LTP/LTD rules. People have gotten them to work, after a fashion, in vivo: Yang Dan's group shifted the orientation of V1 neurons and Dan Shultz's group has some cool backwards conditioning stuff in rat barrel cortex. However, the effects are small and often require a heroic, unphysiological amount of effort, so....there must be more to it than that.

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

#27

Post by miika »

There is also another model about memory which I totally love. In that memory is not stored but brain is more like an antenna which can retrieve information from the space time coordinates where events actually took place.

Because everything is constantly moving around something each event in the universe probably has unique location, a real physical place where it happened.

So, the idea is that as we’re moving through space we’re leaving a trail as the events are (lack of better word) “printed” in the fabric of space. Then as apparently Space is not empty at all but filled with Planck scale micro wormholes entangling all things into this one universal neural network, then our brains should be very well capable of tracing back our unique trails through space and retrieve information through those micro wormholes.

As developer I think it would make most sense to only save references rather than trying store all events inside everyones brains. That would be huge waste of resources and just damn stupid.

And probably the way we humans have built our computers also reflects how the universe really works, because after all we are bits of the universe doing whatever the universe is doing.

Peace

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

#28

Post by omegadeep10 »

miika wrote: post #27

There is also another model about memory which I totally love. In that memory is not stored but brain is more like an antenna which can retrieve information from the space time coordinates where events actually took place. Because everything is constantly moving around something each event in the universe probably has unique location, a real physical place where it happened. So, the idea is that as we’re moving throu…

This reminds me of the book Recursion by Blake Crouch. In the book, scientists figure out how to use memories to time travel. Interesting concept.

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

#29

Post by phantompeace »

miika wrote: post #27

There is also another model about memory which I totally love. In that memory is not stored but brain is more like an antenna which can retrieve information from the space time coordinates where events actually took place. Because everything is constantly moving around something each event in the universe probably has unique location, a real physical place where it happened. So, the idea is that as we’re moving throu…

Created an account to say that this post has probably changed my life. What an extremely interesting thought.

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

#30

Post by lm28469 »

miika wrote: post #27

There is also another model about memory which I totally love. In that memory is not stored but brain is more like an antenna which can retrieve information from the space time coordinates where events actually took place. Because everything is constantly moving around something each event in the universe probably has unique location, a real physical place where it happened. So, the idea is that as we’re moving throu…

> As developer I think it would make most sense to only save references rather than trying store all events inside everyones brains. That would be huge waste of resources and just damn stupid.

> And probably the way we humans have built our computers also reflects how the universe really works, because after all we are bits of the universe doing whatever the universe is doing.

I think this is way too simplistic. Just like planes don't fly like birds, computers don't work like "the universe"

We don't know much about the brain at all and starting to think about it in terms of "computer" logic seems very wrong to me. Computers are our very crude and poor attempt at replicating brains/intelligence, by definition they're built on ultra simplified principles that our own brains came up with, using computer terms to define the brain/universe is closing a loop that doesn't exist

It only sounds like a waste because you(we)'re constrained by our own brains, the universe doesn't care about our ability to understand or make sense of it. Something might sound unoptimised to you(us) but might be the only way allowed by physics.

Naming and defining computer parts using human/brain related terms was an error imho, it confuses people and make them think we are able to replicate (or even understand) things that we have no clue about, they're very poor analogies.

> That would be huge waste of resources and just damn stupid.

Isn't the entire universe a huge waste of resource and just damn stupid ?

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