The brain perceives color when light falls on the retina and interprets these colors by sending the light, as electrochemical signals, to the brain. The rods perceive night vision while the cones at the retina perceive color.
It’s not so simple as that because vision involves more than just perceiving darkness and color. It includes, as this BrainHQ.com article describes it, distilling foreground from background, recognizing objects in various orientations and accurately interpreting spatial cues.
A dress was recently posted on tumblr.com (click to see it yourself), the social networking site, and the question was: what is the color of the dress? Is it white and gold, or blue and black?
The question brings up the concept of how the brain interprets color. At least, the following factors determine how your brain interprets colors so you do not go about thinking you must have an eye problem.
- Time of the day, whether during the day, when the cones are at work, or the night, when the rods are more at work.
- Surrounding light conditions or illumination.
- Distance between the eyes and the object or dress, in this case.
- Medium of perception: air, monitor, cellphone screen or TV screen.
- Stored memory of past experiences and interpretations.