URL: https://www.nature.com/articles/s41593-022-01020-w
It’s currently requested on r/scholar
These results are consistent with the results collected here (which I definitely need to update, geez time has been absolutely flying this year (or in brain lang, lots of boundary changes!).
Really exciting to see how quickly so much of this has been coming together over the past year! By the end of this year I believe we will be able to describe the cognitive process in animals at the cellular level. This is just the pure science, experience says that overcoming the inertia of prior belief structures will take a few years longer. Having this fleshed out model will however provide a granular and personalized map for understanding function in a way I can barely imagine right now.
I keep using the word exciting but we are finally crossing the magic barrier, and this will allow us to not only mediate a significant majority of all human suffering, but allow us to optimize our processes to be less destructive to not only ourselves but the world around us.
With regard to the study itself, the important take aways are that the constructs we were using (e.g. “Place/Location” cells) were already corrupted concepts. These boundary mechanisms work in a much more generalized manner than the behavioral pigeonholes people keep insisting on shoving them into. The second takeaway is probably not much of a surprise, but engrams are created in response to change. Brains create “soft” boundaries for changes in scene objects, and “hard” boundaries for changes in scenes themselves. The weight of the boundary is almost certainly determined by the various valences center, in this study they noted the amygdala’s influence on external stimuli boundaries. These are valence weights are combined together as part of the hippocampal transform.
Edit: I should also add that this particular study is fairly weak on it’s own, it’s only the consistency with recent evidence along the same path that makes it really noteworthy. Just by itself, the effect sizes here are way too small to explain the effects being asserted, however if we take into account this is focused on a single downstream input (temporal lobe) and valence center (amygdala complex) instead of the complete set of processing from all the valence centers the weak effect sizes make sense in aggregate. I imagine the ventral stream being “internal” makes it a lot harder to generate test structures for so it will be awhile before we see confirmatory work focusing on the habenula complex, but we should see very similar effects from that side as well.