Video Lecture of Kropff & Treves, 2008

Update: I recorded a video lecture on this topic:

The slides are at


Kropff & Treves, 2008

HTM Spatial Pooler

A Theory of How Columns in the Neocortex Enable Learning the Structure of the World


@dmac thanks for you presentation.
Could you please share your C++ SP implementation with HTM.core?

I’ve implemented this several times, but I may not have a code solution ready for you to use:

@dmac thanks for your information. Unfortunately i Did not find any branch named GridCells. Maybe it is ColumnPooler2?
Could you pls check it again?
Where is your demo with Mnist?

Yes, the branch is named “columnPooler2”. I linked to its PR in my previous response.

I have demonstrations using MNIST, but they are not related to this topic. is a HTM-scheme translation of @dmac’s code (so a replication2 of Kropff & Treves 2008 :slight_smile: )

One small change is to increase coordinate encoder radius and width every 50000 cycles (see lines 193-201). Results after 200,000 training iterations appear similar to @dmac’s (trained for 1,000,000 iterations).

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@dmac Very nice explanation, i was struggling with lot of things that was covered with this. Thank you so much for this video ! :+1:

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