Kevin's Watch

Anybody read Scientific American Mind? Loremaster perhaps?

I've poked through it, but only when I'm at the library. I dont have a subscription or anything.

The article in question is about grid cells that have something or other to do with memory. I found it on this page:
blog.sciam.com/index.php?title=grid_cells_putting_rats_in_their_places&more=1&c=1&tb=1&pb=1
Grid Cells: The Brain's Graph Paper, and Then Some

I have questions. Heh. It seems the comments section of that page is closed, but I wrote to the editor.

Very, very interesting...I liked this guy's comment:

How can it be avoided that brain research is misused - e.g. by not-democratic people?

Fist and Faith wrote:Anybody read Scientific American Mind? Loremaster perhaps?

Imissed that article. Thanks for reminding me!

David Dobbs, the editor of the Mind Matters section of the magazine wrote back to me.

David Dobbs wrote:

Fist and Faith wrote:1) Does *every one* of the tens of thousands of cells project its own grid onto the area we look at? This seems a bit much, as I would expect all the intersecting lines to become one big blob.

Under the current view, Yes, every one of these tens of thousands of cells does project its own grid. This is one of the amazing things about the system: That the brain somehow makes sense of the feedback, which seems a major computational challenge. Yet that's the thinking at this early point.

David Dobbs wrote:

Fist and Faith wrote:2) Does a grid remain stationary, as it were, as we move throughout the area where it was projected? Or does it move continually as we walk through a room?

The grid remains stationary, as it were, but its (as yet vaguely defined) borders move along with the rat, somewhat as a field of light cast by a lantern does as you walk through the night.

He also gave me this link: tinyurl.com/2xqlru

This reminds me of a lecture I heard two days ago, by a professor from Harvard, in which he was discussing how nerve cells establish their connections with muscle cells, and he showed nerves growing, innervating the muscle cells, "fighting" with each other for dominance, and the defeated nerves retreating while the winners established their connections. Afterwards, he described how he needed a mouse model for that experiment, and how he created the "brainbow" mice whose brain cells contain randomly selected fluorescent proteins; he showed a picture of what a brainbow mouse's brain looked like, and it seemed to watch a painting - thousands and thousands of nerve branches flowing in the same direction, each one of a different color, and each one aiming to different areas of the body. It's amazing