This is RONS RESPOND TO THE MAIN DISCUSSION QUESTIION UR WORKING ON NOW u can use it as a sample

Carlson and Birkett (2017) advance the seminal idea of the trichromatic theory, namely the idea that color vision is based on sensitivities to three primary colors. These primary colors are blue, green, and red. It should be noted that color blindness is generally the result of the absence or reduction of one or more cones stemming from genetic abnormalities. For example, dichromats, are missing one cone, but still have two remaining cones to perceive the other colors. So red/green dichromats can see many colors but have trouble distinguishing reds as those that have all color cones (Lilienfeld, Lynn, Namy, and Woolf, 2011).

          Nevertheless, Lilienfeld et al. (2011) elucidate that there is an interesting phenomenon that trichromatic theory cannot explain, which is afterimages. Afterimages occur when one stares at a color for a long time and then looks away. In an interesting outcome of this process, the afterimage is a different color replica of the original image. Opponent process theory endeavors to explain this interesting outcome which trichromatic theory does not address. The opponent-process theory holds that people perceive colors in terms of three pairs of opponent cells, namely red or green, blue or yellow, or black or white. The afterimages appear in one of these opposing colors. Lilienfeld et al. (2011) elucidate that ganglion cells of the retina and cells in the visual area of the thalamus respond to red spots are inhibited by green spots or respond to blue spots and inhibit yellow spots,  or respond to black spots and inhibit white spots. The nervous system uses both trichromatic and opponent processing in color vision.

          A few interesting points regarding the above phenomenon. First, two theories that ostensibly appear to be contradictory may be complementary. This can be seen with trichromatic theory and opponent processing theory, which are not adversarial theories, rather they both have utility in explaining different visual processes.

        Additionally, historically, the author wondered how people explained such an occurrence of afterimages. Perhaps, this gave corroborating evidence for the paranormal. Neher (1990) advances that the concept of afterimages may have given reason for people to believe in mystical forces manifesting from physical energy. Yet, in the late 1800s, a theory was first proposed by German physiologist Ewald Hering to anchor this experience in science. He advanced that since certain colors oppose one another, they cannot be seen at the same time. Therefore, each color is seen separately, while suppressing the opposing color. Afterimages appear when the original color is removed, giving way for the suppressed color to manifest.

Here is a video link that demonstrates an afterimage:

Color Flag Afterimage

References

Carlson, N. R., & Birkett, M. A. (2017). Physiology of Behavior, 12th Edition. Boston, Massachusetts: Pearson.

Lilienfeld, S.O., Lynn, S.J., Namy, L.L., Woolf, N.J. (2011). Psychology: From Inquiry to Understanding. Boston: Allyn & Bacon Publishing.

Neher, A. (1990). The psychology of transcendence. New York, NY: Dover.

Find a Youtube video or similar source with an interesting visual illusion. Provide the link for your peers to also be able to watch the illusion. Based on your understanding of the visual system, describe which neurologic processes (such as lateral inhibition or opponent process color vision) might explain this illusion.

**Discussion board posting requirements: For each discussion board, be sure to have one main post of at least 400 words and two reply posts of at least 200 words in order to demonstrate sufficient depth to your responses. To receive the highest grade for the discussion board posts, be sure to integrate the textbook as well as additional scholarly sources to support your contributions. Take a look at the empirical literature and include peer-reviewed journal articles to support your posts. Please have your posts submitted on at least two separate days (e.g., don’t post your main post and reply posts all on the same day). This will be worth one point per discussion board and falls under the “Advances Conversations” portion of the discussion board rubric. This helps to spread out the conversation over the course of the unit, and it gives every student the chance to respond to the discussion at a time convenient to their schedule (instead of most of the discussion occurring on the due date). Reply posts can be to either your peers’ posts or to the instructors posts.