Matt christened this branch thread “Universal Encoder”. I’m talking to the theme that the important encoding is done in neocortical like structures across species. (Actually still relevant to @karchie 's original “The art of SDRs” thread arguing SDR’s need to be heavily preprocessed, but that’s labels for ya.)
Anyway, here’s another amazing paper on common neocortical structures across cognitive species. Murray Shanahan at UCL has broken down the connectivity of an entire avian neocortex analogue:
Large-scale network organization in the avian forebrain: a connectivity matrix and theoretical analysis, Murray Shanahan,1,* Verner P. Bingman,2 Toru Shimizu,3 Martin Wild,4 and Onur Güntürkün5, Front Comput Neurosci. 2013; 7: 89.
Among other interesting aspects they encoded the entire connectome in a connection matrix and ran some network stats on it. Since I’ve been looking at @mraptor 's matrix abstraction of the CLA (http://ifni.co/bbHTM.html) I wonder if it might not be interesting to run some of the same stats over the connection matricies he derives. That would provide a concrete comparison of HTM networks to biology.
Apart from providing a potential test for our own network connectivity, and providing a neocortex analogue home for encoding outside mammals, the contrastive biology thing is excellent for drawing attention to what may be truly important in the neocortex. It turns out in birds functional groupings of cells are not localized in the physical sense (maybe not so easy to interpret MRI’s a la Tom Mitchell in birds?), and not layered. Suggesting layers in the neocortex may be only artifacts of cell types and not spatially functional. Instead what is conserved contrastively are “small-world networks” (most nodes not neighbours, but only a small number of nodes apart.)
I think “small-world networks” are what you would expect if connections code sequence. Not all states can follow each other, so you would not expect universal connectivity if connections code sequence.
So, perhaps this contrastive evidence from the corresponding structures in birds supports the idea synapses code sequence (and cells associated with similar functions connect richly, also “small-world” = temporal encoding??), but that physical layers in the neocortex may not be functionally significant (suits me, because I want to find hierarchy in the predictive connectivity, a perfect fit for observed “small-world” network structure.)