Dr. Mark Lindsay was 5 years old when he first learned that tree trunks were brown. "Up until that point, I believed leaves and trunks were all green. Just lighter and darker shades," Mark said. Mark ...

There are three main types of color vision deficiency: red-green, blue-yellow, and complete. Color blindness, or color vision deficiency, affects the way you perceive color and can make it hard to ...

You may know someone who can’t tell the difference between specific colors — and there is a scientific reason it could be happening. The condition is known as color blindness. To share a better ...

Daltonism is a specific type of red-green color vision deficiency, also known as color blindness. People with red-green color vision deficiency may confuse colors that contain red or green elements.