From MSNBC:
The first images ever made of retinas in living people reveal surprising variation from one person to the next. Yet somehow our perceptions don’t vary as might be expected. As they took pictures of the thousands of cells responsible for detecting color in the deepest layer of the eye, scientists found that our eyes are wired differently. Yet we all — with the exception of the colorblind — identify colors similarly.
The results suggest that the brain plays an even more significant role than thought in deciding what we see.
More here.