# Systems Diagram and understanding of the Neo Cortex

**URL:** <https://discourse.numenta.org/t/systems-diagram-and-understanding-of-the-neo-cortex/6337>\
**Category:** Numenta Theory\
**Created:** [July 20, 2019, 2:55pm UTC](https://discourse.numenta.org/t/systems-diagram-and-understanding-of-the-neo-cortex/6337 "2019-07-20T14:55:16Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![gibsonf1](https://yyz2.discourse-cdn.com/flex030/user_avatar/discourse.numenta.org/gibsonf1/32/4308_2.png) [@gibsonf1](https://discourse.numenta.org/u/gibsonf1)\
**Post date:** [July 20, 2019, 2:55pm UTC](https://discourse.numenta.org/t/systems-diagram-and-understanding-of-the-neo-cortex/6337/1 "2019-07-20T14:55:16Z")

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Is there any information available on a systems understanding of the Neocortex, ideally using a metric based systems engineering framework? For example, how a particular neuron type acts as a system, its performance, resource and functional requirements, its dependencies to other systems and subsystems, the Cortical column as a larger system, etc

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**Author:** ![Bitking](https://yyz2.discourse-cdn.com/flex030/user_avatar/discourse.numenta.org/bitking/32/3099_2.png) [@Bitking](https://discourse.numenta.org/u/Bitking)\
**Post date:** [July 20, 2019, 4:28pm UTC](https://discourse.numenta.org/t/systems-diagram-and-understanding-of-the-neo-cortex/6337/2 "2019-07-20T16:28:15Z")

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I have been pursuing this same thing for a long time.  
I have been posting information on various levels at different times.  
At the lower levels this paper is about as good as any I have seen:  
Cortical Neurons and Circuits: A Tutorial Introduction - Richard B. Wells - April, 2005  
[http://www.mrc.uidaho.edu/~rwells/techdocs/Cortical%20Neurons%20and%20Circuits.pdf](http://www.mrc.uidaho.edu/~rwells/techdocs/Cortical%20Neurons%20and%20Circuits.pdf)

Moving up to the mini-column level this paper is an excellent resource:  
The columnar organization of the neocortex - V B Mountcastle - 01 April 1997  
[https://academic.oup.com/brain/article/120/4/701/372118](https://academic.oup.com/brain/article/120/4/701/372118)

This post covers the larger dimension of spacing between the mini-columns:

> [@Project : Full-layer V1 using HTM insights](https://discourse.numenta.org/t/project-full-layer-v1-using-htm-insights/3771/35):
>
> I have been conversing with @gmirey for some time on this general topic. We endeavored to get a sense of the scale of the relative dimensional quantities of the temporal layer, inputs and cell/column spacing, number and range of the connections. You know - the basic facts of making a realistic model. Some of what was discussed was what is known about reach and density of the dendritic arbor in the “input” layer. We established the key factors would be: what is the spacing of the ascending cort…

I have spent some time on the forum trying to bring out the system level behavior of the inter-column connections and emergent signalling - perhaps best covered in this rather long post:

> [@HTM Mini-Columns into Hexagonal Grids!](https://discourse.numenta.org/t/htm-mini-columns-into-hexagonal-grids/3567):
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> Or at least some wild conjectures to provoke thought! This post assumes that you are familiar with basic HTM theory and are conversant with the concepts of SDRs and HTM minicolumns. May I be so bold: First - let’s be clear what I am and am not talking about. This is about cells that work by forming regular hexagonal grid structures and are not necessarily the same thing as the “grid cells” that are coding some spatial aspect of the surrounding environment. These grid-fo…

Moving up another level, map to map connections and the overall organization of the entire cortex, another very long post:

> [@Grids into Maps!](https://discourse.numenta.org/t/grids-into-maps/3618):
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> This is a companion to the post HTM Columns into Grids Sure Grids are cool - News Flash- so are Maps! The reinforcement within and between maps goes a long way towards a general solution of the binding problem. One of the “breakthroughs” for me is that the [cortical.io](http://cortical.io) people have formed the [SOM](https://en.wikipedia.org/wiki/Self-organizing_map) all in a single batch. While very powerful this is not biologically plausible; the brain learns online as data is presented to it. I am thinking that with an attractor model that is formed as the cont…

I have been nibbling on the lower brain structures for a long time but I don’t have a single post that ties them all together. The problem is that they are not a regular as the cortex to each structure really needs its own detailed section.

I would be delighted to see this all combined into a single rigorous resource.

I have collected pointers to much of my exploration of various part of the brain in this post and related thread. I don’t think it is as rigorous as you are seeking but at the time I did the individual posts I was not thinking of these things as parts of an overall system - I have been thinking about each in isolation. Some of these posts dive into various sub-cortical structures:

> [@Basic system level diagram of the brain](https://discourse.numenta.org/t/basic-system-level-diagram-of-the-brain/5834):
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> HTM seeks to model and understand what is going on in your head. I tossed this drawing together from memory so it is sure to be missing some connections. I skipped the thalamic connections all together as this was already a very complicated drawing. Also not shown are the connections between the limbic system and the stream passing through the brain stem and the cerebellum. These are important but not necessary to illustrate the basic cortical/limbic data flows. The blue maps are cortex compose…

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**Author:** ![gibsonf1](https://yyz2.discourse-cdn.com/flex030/user_avatar/discourse.numenta.org/gibsonf1/32/4308_2.png) [@gibsonf1](https://discourse.numenta.org/u/gibsonf1)\
**Post date:** [July 20, 2019, 4:58pm UTC](https://discourse.numenta.org/t/systems-diagram-and-understanding-of-the-neo-cortex/6337/3 "2019-07-20T16:58:13Z")

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Fantastic - thank you for the references.

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**Author:** ![Bitking](https://yyz2.discourse-cdn.com/flex030/user_avatar/discourse.numenta.org/bitking/32/3099_2.png) [@Bitking](https://discourse.numenta.org/u/Bitking)\
**Post date:** [July 21, 2019, 7:36am UTC](https://discourse.numenta.org/t/systems-diagram-and-understanding-of-the-neo-cortex/6337/4 "2019-07-21T07:36:17Z")

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**A thing to think about: resources required.**

If you think of each map as the same as a graphics plane, with about 100 or so in the brain you can use this to visualize what a functional architecture might look like.

Assume for a starting point that each map is 1000 x 1000 nodes. Perhaps the same as a mini-column.  
Each mini-column has perhaps 100 cell bodies, each with at least 10 each, proximal and apical dendrites. I will leave it to you to decide how many synapses each dendrite should have, but JH suggests that it could number in the thousands.Due to the important property of sparsity only a few percent of that number would be active at any time the number does dictate memory requirements.

If you shoot for brain-like speeds you will have to process all nodes at least 10 times a second. I have reason to think that the operations to resolve sparsity competition within a map should run at 40 Hz.

The output is about the speed as a ordinary video frame, and a good GB speed router should be able connect the right map processors to move the “finished products” of the local processing. There is no need for any map to have direct access to another maps local processing memory.

Graphics processors can pump out frames at 100 Hz rates so some of the questions revolve around how well you can mate these processes to the kinds of things a GPU does OR how good you might be at designing your own ASIC.

I am assuming that the processing maps to one boxen per map, each with some sort of GPU like processor. If it were possible to make an off-lease workstation run each map, at $300 each, you could build a brain for $300 x 100 or about 30 grand. Not pocket change but also - not a moon-shot kind of thing. It would not require Google or Microsoft (or DOD) resources to make it happen.

As the GPU makers start to shift the designs to be better at neural network tasks this scenario gets ever more doable.

This scheme still leaves the sub-cortical structures as an open question.

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**Author:** ![gibsonf1](https://yyz2.discourse-cdn.com/flex030/user_avatar/discourse.numenta.org/gibsonf1/32/4308_2.png) [@gibsonf1](https://discourse.numenta.org/u/gibsonf1)\
**Post date:** [July 21, 2019, 11:37pm UTC](https://discourse.numenta.org/t/systems-diagram-and-understanding-of-the-neo-cortex/6337/5 "2019-07-21T23:37:31Z")

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I think unlike typical AI approaches that brute force compute through massive amounts of data, a hierarchical approach, especially using SDR, can be extremely efficient. So that a single cortical column 5 levels up the hierarchy could be encapsulating a massive amount of learning, but dealt with in a “simple” way. There is also an idea that neurons (or dendrites) can do multi-processing: [https://actu.epfl.ch/news/the-way-a-single-neuron-processes-information-is-2/](https://actu.epfl.ch/news/the-way-a-single-neuron-processes-information-is-2/) .

I’ll be working on a systems relationship graph and posting here as it evolves in the next few weeks…