A family in the Netherlands has a rare and perplexing brain condition that helps explain how we recognize color.
In his 40s, a Dutch man researchers call MAH suffered a stroke that fortunately left no lingering consequences. Still, he balked whenever doctors giving him the standard battery of cognitive tests asked about colors. It was nothing to do with the stroke, he told them. For his entire life, he had lived without a sense of color.
What did he mean? He had no problem seeing color, his doctors concluded. He easily passed the test for red-green color blindness, finding the numbers hidden in colored dots. He could put very similar hues in the right order. But he could not sort tokens into distinct colors such as red, green, blue, yellow, and orange. He could not identify the colors of the tokens. He could not imagine the color of his car. He could not even understand, when presented with a drawing of garishly blue strawberries, that the picture was odd at all.