Hi Glenn,

Thanks for reviewing the video and asking these questions.  When we perceive a strawberry, we are consciously aware of a 3D space containing a 3D model of the strawberry.  If you break the 3D space up into voxel elements (like 2D pixel elements only 3D) there is a set of voxel elements that is our conscious knowledge of the surface of the strawberry.  Each of those voxel elements on the surface of the strawberry can have a redness quality, or they can have a greenness quality if the input is red/green inverted.  The important point is that there is some neural correlate that is each of these 3D voxel elements of color of our conscious knowledge of the strawberry in our brain.  Like how RoboMarry can have abstracted knowledge (knowledge that does not have the same physical quality but must be qualitatively interpreted) about everything going on in each of these voxels and their colors, we don 't yet know how to qualitatively interpret this knowledge of what we are observing in the brain.  So we think these neural correlates are all just "grey matter".  A clear qualitative miss interpretation of what these voxel neural correlates are qualitatively like in our conscious experience.

Don 't get hung up on the exact physical makeup of the particular neural correlate of each of these voxel elements of knowledge - as it could be anything in the brain in any configuration.  I just happen to currently think Steven Lehar's theories about what they are is the most supported by the evidence to date and simplest to understand.  (see: http://cns-alumni.bu.edu/~slehar/Lehar.html )  He proposes an actual neuron representing each of the voxel elements.  One possibility is that when it is red that particular neuron's synapses are firing with glutamate, and when it is green that particular neuron is firing with glycine.  It might be the chemical reaction of glutamate in the synapse that may have the redness quality we experience for that voxel.  But this is just one physical theoretical possibility.  You can substitute glutamate with anything else in the brain.  Science will eventually tell us which physical stuff in our brain really has the redness and greenness qualities we can experience for any particular voxel in the visual field.