@gmirey, I see four main points in your assessment:
- Darwinism. Granted that when I first read Calvin I blew this off for much the same reasons you mentioned. I used to think that this was just a personal jihad that got mixed in with his otherwise good ideas.
Time has since whispered to me that my lack of understanding does not make the ideas wrong.
I think that the timescale of when the concept applies is an important consideration. I don’t think this applies to every presentation of a sensed stream. I do think it applies when competing grids are forming and the “boundary cells” are trying to learn what pattern they really are part of. So the correct time scale is during the exploration and learning phases. So - not all at once and not during every recognition event.
- Proximal vs. distal? I think that this is bigger than that. There is a large number of cell types in the cortex, each with different “reach” and different mixes of inputs and output, some excitatory, and some inhibitory. The grid-forming cells and related inhibitory cells are just two types in this mix. The Numenta temporal and it’s related intercolumn inhibitory cells are other cells in the mix.
I hope that you take away that I am only describing a part of the mix of cells in the cortical sheet. I have tried to be careful to distinguish that the layer 2 grid-forming cells are distinct from the standard temporal sensing cells central to the Numenta model. I see them working together as a system.
There are other cells that do not fit into either model such as the thalamocortical cells[1] in layer 4. I am sure that there are more stories to be told here.
Taking your shoe-horn niggle to the Numenta model - they are trying to cram every bit of the cortical sheet into the temporal sensing model seemingly without trying to use these other layers & connections to form larger patterns and connections to distant structures.
All that aside: The grid-forming cells solve a problem that does not seem to get much attention in the Numenta model: binding. Even if I accept the Numenta model as doing everything that is claimed (and I don’t) we still have the problem that this finger says “cup” and that finger say “guard rail” and the palm says “gearshift knob.” Nothing ties them together into a whole and integrates the various sensed states into the whole. The grid-forming layer is in effect allowing the various sensations to vote on a learned thing over a spatial region of a map. Quickly, automatically, and in a biologically plausible way.
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The 100 step thing - excellent observation. First - see #1 above. Second - all the local cells are trying to recognize some pattern at the same time. If there is some overarching pattern that the local cell is part of it gets an extra “kick” from its grid-spaced neighbors helping it to become fully active. All of the grid-forming cells are trying to see the pattern at the same time so it is a relatively fast local process.
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Regulation. Good point - seldom discussed. Note that at the level of the Numenta model you almost ever hear anything about brain waves or tonic maintenance. I don’t have a ready answer but I think this deserves more attention. I did mention some things about this in an earlier post[1] but did not follow-up on it.
Discussion: As you may have noticed - I read a fair number of papers; I try to understand the ideas being presented and move on to the next one. Some central tendencies emerge and often I see that the work done in the paper is not all that helpful by itself but that unintentionally it does offer support to other work in other papers. The Calvin books fit in that space. When I first read them I was entertained and I did check out some of the related references. It all checked out but I could not see much use for what he was saying and I filed it away with the vast number of proposed models of “how the brain works.”
Then the Moser Grid findings hit the scene and I went back and looked at anything that I had seen related to grids and was struck with how nicely Calvin’s work anticipated this. Then I (finally) made the connection with the binding problem and got serious in looking at his work. Even if Calvin’s work turns out to be wrong it does such a good job of explaining the meta-behavior of grids that I think it is useful as a starting point to evaluate what grids are doing.
Note: I would be delighted to post some of the papers supporting Calvin’s work but these were done in a different time. All of them seem to be either behind a paywall or in a book. The ones that I did obtain through interlibrary loans did seem like good solid technical support for his main points.
[1] Cortical Oscillations: A topic seldom discussed in HTM circles: