[artiszt]

>the visual pathway does some math to reinterpret RGB as a closed circle of hues we see in our visual field<

sort of, computation of 'contrast' so to speak, or, in broad terms, differences in wavelengths

most likely done, foremost and in essence, in area V4, cortically. if damaged, cerebral achromatopsia [colour blindness results]. patients won't even see/perceive induced 'coloured' visual phenomena, such as phosphenes [Farady made a few quid by electro-shocking ppl, for instance in Jardin des Tuileries, Paris : electro-magnetc impulses applied transcranially to the occipital part of the brain can elicit, in some subjects, brief bright colourfull light sensations]