[extropy-chat] effing

[gts]

On Tue, 06 Dec 2005 14:09:06 -0500, Brent Allsop <allsop at extropy.org>  
wrote:

> It'd sure be nice to know what is required to connect two conscious  
> worlds together like this.  I bet we'll know before 10 years.

Here's a step in that direction, concerning the neural correlates of color  
perception:

==
Neuroimage 2004 Apr;21(4):1665-73    (ISSN: 1053-8119)
Morita T; Kochiyama T; Okada T; Yonekura Y; Matsumura M; Sadato N
Graduate School of Human and Environmental Studies, Kyoto University,  
Kyoto, Japan.

It is well established that seeing color activates the ventral occipital  
cortex, including the fusiform and lingual gyri, but less is known about  
whether the region directly relates to conscious color perception. We  
investigated the neural correlates of conscious color perception in the  
ventral occipital cortex. To vary conscious color perception with the  
stimuli-remaining constant, we took advantage of the McCollough effect, an  
illusory color effect that is contingent on the orientation of grating  
stimuli. Subjects were exposed to a specific combination of chromatic  
grating patterns for 10 min to induce the McCollough effect. We compared  
brain activities measured while the subjects viewed achromatic grating  
stimuli before (PRE) and after the induction of the McCollough effect  
(POST) using functional magnetic resonance imaging (fMRI). There were two  
groups: one group was informed that they would perceive illusory color  
during the session (INFORMED group), whereas the other group was not  
informed (UNINFORMED group). The successful induction of the McCollough  
effect was confirmed in all subjects after the fMRI experiment;  
nevertheless, only approximately half of the UNINFORMED subjects had been  
aware of the color during the POST session, while the other half had not.  
The left anterior portion of the color-selective area in the ventral  
occipital cortex, presumably V4alpha, was significantly active in subjects  
who had consciously perceived the color during MR scan. This study  
demonstrates the activity in a subregion of the color-selective area in  
the ventral occipital cortex directly related to conscious color  
perception.
===

Interesting that the brains of all the test subjects registered the  
McCollough effect but only half of the uninformed test subjects noticed it.

One might ask, "Where did the qualia happen?" One answer seems to be  
*conscious awareness of the qualia* happened in the left anterior portion  
of the color-selective area in the ventral occipital cortex, presumably  
V4alpha.   But conscious awareness of a quale may not be the actual quale,  
and is not according to the theory I've been entertaining here.

Did the quale exist in the minds of those who didn't notice it? As we've  
been discussing here, there is the phenomenon I call "blind-sight" which  
seems to suggest that conscious awareness of qualia is separate from the  
basic awareness of them.

This abstract states that successful induction of the McCollough effect  
was confirmed in all subjects but does not explain how they knew this.   
Perhaps the answer to that question is a better answer to the question of  
where the qualia happened.

One could then say that in this study all the uninformed subjects were  
*aware* of the effect but only half were *conscious* of it, i.e., only  
half were aware of their awareness of the effect.


Here's an online illustration of the McCollough effect:
http://research.lumeta.com/ches/me/

-gts