Tetrachromacy is a rare genetic trait that endows people, primarily women, with a fourth color-detecting cone in their retinas. Most humans have three cones in their eyes that detect variations of ...

View Full Profile. Learn about our Editorial Policies. Humans rely on sight, which is primarily mediated by three color-sensing cone types, to perceive the world in a kaleidoscope of hues. Blue cones ...

Here's how the glasses can help. Most people have three color cones in their eyes. Blue, green, and red. The ratio of light for each incoming color is then sent to your brain. This ratio tells ...

This color blindness test is a simple eye test to find out whether or not you are color blind. There are small color sensing granules known as cones in the nerve cells of our eyes. Color blindness is ...

The retina is home to two different kinds of light receptor cells—rods and cones ... eyes reflects back a flashlight or some other light source. (Interestingly, different animals have different ...