Spatial Pooler and Distal dendrites

In the SP there seems to be no use of the Distal dendrites only Proximal/FF which connect to the receptive field.

Any idea why not ?

My speculation is that there is no separation between SP & TM i.e… they are single entity ! i.e. Predictive and Spatial learning happen simultaneously ??!


Tbh I really don t know if I understood what you mean but the spatial Pooler consists of extracting semantic information from input and provide a controlled space to perform further operations where the The temporal memory represent the parse input that capture the temporal context and forms a prediction based on the input. so basically there is a different

SP is implemented as biological Neurons with only Proximal FF dendrites … and TM is implemented as Columns of bio-neurons with only Distal FB dendrites (plus ONE proximal 1|0 synapse per input bit, instead of full receptive field … which will mimic SP)

What I’m saying that implementing biologically plausible scenario will require for SP and TM to be merged in single module,

I think SP and TM generally are combined in practice. It’s just helpful, from a software engineering practice, to modularize functionality in human-understandable ways. SP and TM can be used separately for different functions and experiments which I generally do.

SP kind of “scrambles” or “compresses” the information and makes it harder to understand just by inspection. If you use a different input to TM that you control explicitly, (such as a scalar encoder), it makes it easier to understand the mechanics of the TM by inspection, seeing the predictions as they are made. Once you have a good intuition of their mechanics independently, then you can combine them with more confidence and have a good sense of how to fix things if they aren’t working how you expect.

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yes thats what i assumed too… i started 3rd re-implementation, this time with stylized HTM-neurons … i got so far 11 different possible structures which include SP and TM as special cases

trying to clarify the process so i can implement it

what are these 11 different possible structures? and what is a stylized HTM neuron?

In the other thread I mentioned the 11 structs.
I mimic HTM neuron as close as possible … the difference is they always come in groups never in ones.
I distinguish between FF and FB (which can be Local and/or Remote /Distal,Apical/) connections. FF&FB are treated as per HTM.

In fact I can have multiple FF and FB groups …

Yeah the big difference is groups of neurons are build from a group of segments:synapses and then I build the processing around it by combining those in single module… i calculate for modest use i will need 3 - 30MB per module …

The only thing i dont know how to app roach is FF&FB growing&deleting segs&synapses … the arrays that hold the data can grow or shrink, just cant figure out the conditions

Distal dendrites are here to make a winner take all by brining down their cells spiking threshold level so cells fire a tiny bit faster. they are top down signals not a buttom up (feature detection). So soatial pooler hasn’t yet built that in…doesn’t mean they wint in furure iteration of what ever implementation of their software comes next.

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good point on top-down and bottom-up…

i’m thinking on Rank-WTA for FF, then pass this as input to FB , where i do Rank-WTA again.

First may be at 5%, second at 2% !!

if its a threshold-WTA i’m not sure about what threshold to put.

Or if i can do both and select with parameters which to use