Comment by randomImmigrant

> 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.