Final answer:
Color vision is processed through two theories, the trichromatic theory at the retina level and the opponent-process theory beyond the retina. Inter-neurons involved in color opponency contribute to the perception of color by being excited by one color and inhibited by another, preventing certain color combination perceptions, and leading to negative afterimages.
Step-by-step explanation:
The inter-neurons mentioned in the question are likely referring to cells in the visual system that contribute to the processing of color vision through mechanisms of color opponency. The opponent-process theory states that color vision is coded in opponent pairs: black-white, yellow-blue, and green-red, with certain cells excited by one color in the pair and inhibited by the other. This process prevents the perception of certain color combinations, such as yellowish-blues or greenish-reds, and leads to the phenomenon of negative afterimages.
In the retina, photoreceptors show tonic activity and are always active to some degree. Rods and cones, when stimulated, alter the rate of neurotransmitter release, which then influences bipolar cells. The signal is further modified by horizontal and amacrine cells, creating lateral inhibition and enhancing image contrast. Retinal ganglion cells (RGCs) then transmit the visual signal through the optic nerve to the brain. While the trichromatic theory applies primarily to the cones in the retina, the opponent-process theory is more relevant once the signal moves beyond the retina towards the brain.