A single memory is stored across many connected brain regions
news.mit.edu
news.mit.edu
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
This isn't a peer-reviewed journal, nor the Bible. And your comment contributes too, by pointing out it isn't consistent with Western medicine. You're helping the reader who happened to buy into that, not to try combining it with scientific mainstream things, not talk about it at the water cooler, and not talk about it for instance when being psychologically evaluated. Like even if the psych likes you if you say things like that it's out of his hands and he has to flunk you. That's the mistake Feynman made, he talks about flunking a psych exam for the military, but like full-on full F, like they used special words to describe how poor they judged his mind to be, and then he replied to them accepting the F and asking to be flunked harder on the basis it was clearly crazy to write them that letter.
And he was constantly thinking about the fabric of the universe, entertained many wild theories to arrive at sound ones, I'm sure of that.
But yeah, thanks for saying that, in case readers didn't take that comment with a grain of salt. Yours was the grain of salt.
> 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 ?
That's fun enough if that's intended as some form of recreational speculative fiction/sci-fi. I'm all about that.
But you said "model", without qualification, so its hard for me to tell from your comment the extent to which you want to put this forward as something that stands a chance of really being true.
That's unlikely to have any resemblance to how brains work though. For one, we would be lacking the mechanism to do such a 'retrieval'. We can also influence memory formation.
Say you binge drink. You are temporarily unable to form memories. We can pinpoint the exact area affected. Unless alcohol is somehow able to influence the micro-wormholes, it shouldn't affect memories at all.
> As developer I think it would make most sense to only save references rather than trying store all events inside everyones brains.
Remember, nature does not care about that.
I can't believe this comment isn't buried. Its one thing to engage in a bit of rank speculation outside your specialty, but this is straight-up crackpot science.
If a site keeps doing that, competent people go elsewhere. Why is that post the top comment on an interesting paper from MIT?
Being inflexibly and uniformly critical of all ignorance also drives people off. And the direct subject to a reply isn’t always the most important audience. Sometimes you’re persuading people who are passively reading along. If that sounds absurd in this scenario, consider the number of times a gentler rebuttal in a discussion has given you pause to reconsider some foolish idea you hadn’t expressed. If you can’t think of one, you’re either an outlier genius or maybe overconfident and overcompensating.
Either way, most people aren’t dissuaded of their ignorance by being chastised for it. Speaking as someone who’s lost important friends learning that the hard way.
References make sense to me as well, but I also agree with the conclusion of this article, that memories are distributed. If you put the two together, then I think it works well. Those could be distributed references, that when fired together, activate a specific memory somewhere else in space-time.
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 (currently led by the Tonegawa lab) that think that memories are associated with individual neurons.
No, we don't.
https://diyhpl.us/~bryan/papers2/neuro/The%20mechanical%20ba...
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 activated first.
NMDA is much more complicated in that it requires binding both glutamate and another neurotransmitter, glycine, for the ion channel to open. But this ion channel can also be blocked by Mg²+ ions, which for reasons that currently escape me, is removed when the neuron depolarizes. Once NMDA is open, it has the downstream effect of upregulating the AMPA receptor, making more sensitive to future transmission, hence serving as a kind of "memory" of previous signals. I think the open question is more about understanding how memory as we know it emerges out of networks of these neurons, and less about the basic cellular mechanisms. And this is probably only one mechanism of LTP, then you have its opposite, Long Term Depression, which is also involved.
Of course, in science the answer is always more complicated than what can be gleaned from the hand-wavey explanations of some programmer on HN :)
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.
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.
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 upon first experiencing the stimulus. Compare that to a computer pulling a png from storage, loading into memory, calling necessary drivers to present onscreen, etc.
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...
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.
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.
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 for deep learning is that information is stored in the weights and any given output is a function of all the weights. Some weights are more important than others in producing the output, but the point still stands.
On a technical level of course the whole network contributed to the output. In everyday reasoning and language however we usually focus on the parts that matter to a reasonable degree and ignore the rest. A sack of rice falling over in 2005 might have contributed to the 2008 financial crisis. With the world being an analog network of particles it even seems obvious that that sack of rice must have had some infinitesimal influence one way or the other, it's just more practical to ignore it.
https://www.sciencedirect.com/science/article/abs/pii/S08966...
> When NMDA receptors were removed, a much simpler network (fully connected neural network with one hidden layer) was sufficient to fit the model.
Put simply: if you have two related concepts, say "car" and "truck", then it makes a lot more sense to me that they'd be represented by similar weights among a collection of neurons, than if each concept got its own single neuron (or handful of distinct neurons scattered throughout various functional parts of the brain.) If you did that, you'd need to explicitly encode the various similarities and differences. It would take time for priming to travel from one thing to all the related things. There would be no or limited redundancy. Forking off a concept (eg with language, learning a synonym) would have to be some explicit process.
With an aggregate representation, you get all of that automatically. When you're thinking "car", you're 70% also thinking "truck". You can evolve your understanding freely without breaking anything, you can split and merge representations, etc.
It kind of seems obvious to me, which is no proof that it's correct. I'm reading Kahneman's "Thinking, Fast and Slow" right now, and it's a brilliant book yet I feel like this representation would convert many of his puzzled observations into unavoidable consequences.
Separately, I think there's less of a distinction between memory, recall, and actual experience than this paper makes out. They feel the same because in the brain, they are (mostly) the same. And there's more of a distinction between memories of different things. I expect to find very different brain regions involved in memories of pain vs movement vs vision vs procedural knowledge etc., because much of the memory will be in the neurons directly linked to the relevant sensors or actuators. (As above, the memory is the experience, or at least it overlaps substantially.) Sure, there will be overlap across all those, but that's not because it's the One True Memory Region, it's just that there's a generic component to any memory (or rather, anything that we would refer to as "a memory".)