Opponent process theory: why do I see green after looking at white?

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    Green Process Theory
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SUMMARY

The discussion centers on the phenomenon of color perception as explained by opponent process theory, particularly the experience of seeing green after viewing bright white light. The user describes observing a green patch after staring at white blinds and notes that the patch turns purple upon closing and reopening their eyes. Responses clarify that this experience is linked to the adaptation of photoreceptors in the eye, especially under bright light conditions, and that individuals with high myopia or deficiencies in vitamin A or zinc may be more sensitive to these effects.

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  • Understanding of opponent process theory in color perception
  • Knowledge of human photoreceptor types and their functions
  • Familiarity with visual adaptation mechanisms
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  • Research the mechanisms of human photoreceptor adaptation under varying light conditions
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Individuals interested in color perception, optometrists, vision scientists, and anyone exploring the effects of light on visual experiences.

DeuteriumDude
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This morning, I was lying on my bed, looking at the bright morning light coming in through the window. The blinds (which are white) were at least half shut, so much of the light was filtered through them. I then stared up at the ceiling, and saw a nebulous patch of green. I shut my eyes, and the nebulous patch of green became clearer still. I then reopened my eyes, looking again at the ceiling, and the nebulous patch became purple.

Here's what I don't understand: shouldn't the nebulous patch be black, since I was originally looking at something white? A green patch should be left by staring at purple. There is nothing purple in my room or outside my window. And yet, I've had this happen to me before while reading a book under bright sunlight: eventually, everything in my field of vision will look green. Also, why does the nebulous patch turn purple when I shut and reopen my eyes? None of these things seem to follow the predictions of opponent process theory.
 
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My first thought is that you are seeing green in response to red; the eyelids are very thin and full of blood vessels, so if you close the lids while strong light is shining on them, you may be aware that the darkness under the lids is red-tinted if you have the eyes positioned as if to see (not rolled back).
 
Dude, take care of your eyes. :wink:

DeuteriumDude said:
Here's what I don't understand: shouldn't the nebulous patch be black, since I was originally looking at something white? (...) Also, why does the nebulous patch turn purple when I shut and reopen my eyes? None of these things seem to follow the predictions of opponent process theory.
Well this theory is about color perception in steady condition, while here you're playing with adaptation to dangerously bright lights. I'd guess the green switching to purple comes from the relative speed of adaptation of the three photoreceptors types, especillay the blue ones versus the two others.
 
Dude its very normal its just impression of bright light which remains in eyes its happens to indivisuals whose eyes are more sensetive to light like high myopics,or people with vit A Deficiency,zinc deficiency
 

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