alt Hacker News> If someone's hippocampus is destroyed, they lose the ability to form new (episodic) memories, and may lose some more recent old ones, but they certainly do not lose older ones. This is basic knowledge.
Yes, like basic reading without digging into details. You must have heard about HM, since you’re saying all this. But here’s the facts:
When H.M.’s remote memories were probed carefully, they turned out to be gist-like and semanticized, not vivid re-experiencings of specific events. Here’s the paper:
https://pubmed.ncbi.nlm.nih.gov/15716139/
Only semantic memory of the episodes can be said to be “cortical” (though please note, lack of hippocampus doesn’t mean lack of other brain regions…). Rich recall absolutely does require the hippocampus.
Once again, please try not to “spherical cow” the complexity of the brain to try and fit it into your analogy to digital computing. You will get an underdermined model that will miss the subtleties, and lead you to claims that are poor fits for the reality.
As for why I brought up bird brains… there part of the same evolutionary web. Is there some reason you want them excluded? They’re a well studied model for a fairly complex memory task, using substantially smaller neurons more densely packed in a different architecture than mammals.
In cognitive science, as in computer science I’d imagine, it’s useful to look at the full picture before making strong claims.
The bird case is interesting because the region of interest is a nucleus, rather than cortical columns, and actually has well documented structural variations in size, as well as gene expression, over the seasons, while the memories are forming.
If your model is correct, it needs to account for those facts.
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> If your model is correct, it needs to account for those facts.
Let me make it simple for you.
We have a finite number of neurons in our brain, as do birds, and our brain is attempting to store an ever growing number of memories in those. And, no, this is not a digital computer (is your reading comprehension really so bad?).
Nobody, including you, knows exactly where different types of memory are stored, and for my argument it makes no difference. What does make a difference is how they are represented, which I am suggesting is sparse embeddings.
So far, you've been ignoring my actual argument and instead responding to various strawmen of your own making, so it's not clear if you even understand what a sparse embedding is.
If you do understand, then it should be obvious that it makes no difference whether the neurons comprising this embedding space are in the hippocampus, cortex/pallium or anywhere else. Clearly you do NOT understand, since you bring up bird brains (pallium vs cortex) and want to argue about location of storage (hippocampus vs elsewhere) as if it made a difference to MY argument.
My argument (if you care to respond to it, which so far you have not) is that when sparse embeddings have little to no overlap, then associative recall by a similar pattern will work reliably, but when multiple embeddings have too much in common then recall will suffer as multiple embeddings will match.
Hint: if you think this has anything to do with digital computers then you have misunderstood and need to go back and re-read more carefully, or google for any terms you do not understand.
There is 2006 paper "Polychronization: Computation with Spikes" E. Izhikevich. that describes one simulation they have done in silico and it explains how exactly distribution of activity happens and why you can't run out of memory. Basically the small group of neurons, say 10, can represent much larger amount of information say 1000 because they can fire in different orders, that is what they call poly-synchronous activity.