system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why is it that after looking at a bright light source, and then closing your eyes, you see a colorful outline of the light source for a little while?
gpt
Your eyes contain cells that chemically react to light. Stimulating them strongly can create temporary lasting imprints because either the cell is depleted of the signalling chemicals relative to other cells (you look at a red image then switch to a white wall - the red cells are less capable to signal than the green and blue ones so that portion of your vision looks more anti-red) or the cells continue to fire since they are so strongly stimulated (you close your eyes and see bright outlines).