HTM School 14: Grid Cells

In general - yes.

I am very aware of sub-cortical visual awareness.

What I am less sure of is the perceptual mechanism. “We” have a pretty good idea of the general mechanism of the visual path and contents of the cortical visual stream.

I have not seen the same level of description and understanding of this sub-cortical visual perception.
This is important and related to grid cells in an indirect way.

As far as I am aware - nobody really knows how the visual, tactile, and somatosensory information is combined at the level of the hippocampus to form the response or activation pattern that is described in the Moser work. If a mouse navigates by vision or motion or whiskers it all seems to end up forming the same response to locations that have come to be known as grid and place cells.

Most of the work I have seen comes at this from the cortex side. @Gary_Gaulin put up a post today that analyses the relationship between the grid & place cells and if you read this it would seem like this is somehow happening in isolation from the rest of the brain.

My point in all this is that the cortex pathway seems to lead from the raw sensory areas through the WHAT and WHERE streams to the temporal lobe and on into the entorhinal cortex. This is a pathway that is full of learning and serial processing.

The sub-cortical structures seem to be shorter and more hardwired. They come to the hippocampus via the “other” direction and may well play as a significant pathway to forming the place and grid patterns.

This is the bit that I have been trying to learn more about: the hardwired visual system in the sub-cortical structures.

We know it has built in shapes and emotional coding for at least fear. We know that it can guide you around a room when you can’t see at all. It can guide your grasping when blind. It sees faces and expressions. There it good reason to think that it uses features to be sexually attracted - sex linked features that are thought to signal desirables in a potential mate. I’m sure I could name more but this is just a random list. Yes - the male and female brains could be wired/programmed differently.

That’s a lot of lower level processing and it’s tied directly to the hippocampus. It sure would be nice to know more about a few dozen dense cluster of nerves that are doing all this.

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