How the Mind Arises: Network Interactions in the Brain Create Thought: Scientific American July, 2019

Science General Neuroscience
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Here is an issue from Scientific American that all of us in the HTM community should take a much closer look at. I happen to be subscribed to the printed version and found this cover article by Max Bertolero and Danielle S. Bassett (both at Complex Systems Group at the University of Pennsylvania) very insightful into the higher level network dynamics of the neocortex. I beleive they may help us shed some light on the H in HTM (Hierarchy).

Network Neuroscience is the new term, coined by Bassett. The article explores the recent discovery via fMRT studies of network dynamics in the cortex, which can be broken down into 7 brain modules. (I would call these modular ensembles, because these modules are not strictly isolated, localized regions). These modules have the property of always firing in sync, within the module. Each module contains nodes that tend to activate all sections within its boundaries. Graph theory and simulations run by Olaf Sporns have been applied in this study.

The seven brain modules are listed as:

  1. Visual,
  2. Attention,
  3. Frontoparietal Control,
  4. Somatic Motor,
  5. Salience,
  6. Default and
  7. Limbic.

A series of psychological tests with given tasks, has allowed the team to understand which of these modules are involved and associated with each task-type. Some tasks linked to the visual module are, for example: Braille reading, Visual tracking, Action observation, Picture naming (silently), Brightness perception, Silent reading, etc. Interestingly, Braille reading also activates the Attention module. So some tasks activate multiple modules (ensembles). The Salience module seems to be involved in recognizing exceptions. Tasks like Breath Holding, or Awareness of need to urinate, or Stimulation monitoring or Word stem completion (silent). The Frontoparietal Control module is key to Reasoning, as in the Wisconsin Card Sorting Test, or Counting, or Tower of London (complex planning task), or Task Switching Control.

Each of these seven modules includes a set of regions, usually clustered but not always contiguous. So what keeps them together are a set of nodes (small node regions) that interlink the areas in each of the seven modules. There are also some hubs (super-nodes) that inter-connect some of the nodes across some the seven modules. (These are like bridges that connect two modules). These inter-modular hubs activate two or three of the modules during certain given tasks. The article shows the links between a long list of tested tasks (around 73) and the association of each task to some of the seven modules. The strength of these associations is also shown in the diagram.

I highly recommend reading this issue and this article. I am attaching a link to the website from Scientific American, but the aricle is unfortunately not free to access without purchase.

Look forward to some of your feedback, HTM-Community.

Kind regards, Joe Perez (in Germany)

https://www.scientificamerican.com/magazine/sa/2019/07-01/

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@Jeff Hawkins, @Subutai Ahmad, @rhyolight

Dear Matt, Jeff, Subutai, have any of you had a chance to read this article in Scientific American (July, 2019 issue)?

Or in the older related article: **Network Neuroscience – (Danielle S. Bassett and Olaf Sporns) in Nature Neuroscience, Vol. 20, pages 353-364; March 2017?

I would be very interested in your take on this. I have the feeling they are on to something in the mid-levels of the hierarchical organization of the neocortex. But I think, that due to the fact that their data is coming from fMRT to a large extent, they are obviously missing both the lower-levels and the very high-level of the pyramid in the HTM. However they seem to imply that we may have 7 pyramids coexisting. (Kind of like having 7 specialized HTMs coexisting). Do you agree that their findings could be an indication for this? Thanks and best regards, Joe Perez

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Oh good! I am glad that have that worked out.
I assume that they will take this new understanding and crate a functional AI sometime soon.

Seriously, SA has been one of the factors that got me into this field.Their writing is some of the best in trying to inform the casual bystander in what is going on. It is written so that anyone with a well rounded background can approach it.

Reading in the general press; for all the “breakthroughs” we still seem to be a long way from really understanding what is going on in the brain. I never get that little bit from the breathless writing in the more general science writing. Also - and this is not really their fault - they do have to tart up the writing or nobody would read it.

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I agree and share your views on the press. The over-enthusiatic headlines are not really what locks my interest, but when I noticed the topic and context they chose for the cover story, I was very pleased that this area is getting some serious attention. Even though the research in this article is still taking place at a macro-scale that does not allow for insights into the computational mechanisms, the amount of data collected and correlated with specific cognitive tests may bring some insight into the intermediate realm of neural organization. I am curious how this may fit in with our wealth of knowledge at smaller scales.

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