[ExI] What is Consciousness?

[Rafal Smigrodzki]

On Sun, Mar 26, 2023 at 9:39 PM Brent Allsop <brent.allsop at gmail.com> wrote:

>
> Hi Rafael,
>
> I'm not familiar with the fusiform gyrus color rosettes.  It sounds like
> you know more about the current understanding of at least this part of
> neuroanatomy than I do.  So I very much appreciate your help with all this
> stuff.   I've been able to find information on the fusiform gyrus, but
> nothing, yet, about the color rosettes.  So I was wondering if you could
> provide some references where I can learn more?
>

### There was an article in "Science" (I think) about 15 years ago where
they mapped the responses of a class of cortical neurons in the fusiform
gyrus to color visual inputs on sub-millimeter scale. They found that there
was a sheet of cortex tiled with hundreds of little color wheels (I am not
sure if they used the word rosette, I read it decades ago). By looking at
which neurons on the color wheels were activated you would be able to tell
what color light was impinging on the retina in the spots corresponding to
each wheel which means that the neurons encoded color information (i.e. the
result of an attempt by the cortex to calculate the reflectance of
surfaces) which then would be fed to higher cortical areas to enable the
conscious perception of color.

This article shows similar results (but I remember reading about it in a
different article that I can't find now):

https://www.pnas.org/doi/10.1073/pnas.0810943106

See especially figure 1A - there is a circular arrangement of neurons that
respond to different colors. There is of course much more to the encoding
of color in the cortex, there are multiple levels of the brain that express
color information in different and complementary ways, all very complicated
but the basic concept of "chromotopic" mapping is simple.
 ----------------------------

>
> Also, I have a question about this "thing that contains the redness
> quality in the brain."
>
> In our video, there is a chapter called "Perceiving a Strawberry."
> <https://canonizer.com/videos/consciousness?chapter=Perceiving+a+Strawberry&format=360&t=120>
> At 2:00 minutes in it illustrates a single pixel on the surface of a
> strawberry changing from redness to greenness. So, obviously, subjectively,
> there is one pixel physically changing, out of all our colored pixels that
> make up our total subjective experience of the strawberry in the brain.
> So, objectively, what would you see, when one observed just this one
> subjective pixel which is changing from redness to greenness?  How would
> this color rosette mechanism accomplish such a subjective experience of one
> pixel changing like this, Along with all the other pixels of which our
> subjective knowledge is composed, which could also all change to be any
> color at any time?
>

### A couple of neurons in a single color rosette would fire differently,
and this would propagate to higher cortical areas, and as long as you
maintain attention to that pixel there would be reciprocal and sustained
activation between that color wheel and its neurons and the higher cortical
areas.


Rafal
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