LINGUISTIC DISPARITIES ATTRIBUTED TO THE EFFECTS OF ULTRAVIOLET RADIATION

These tropical images represent the perception of colors (left) to those with normal vision and (right) to those with vision impaired by the damaging effects of UV radiation. 

Because it is so highly revered, we rarely take notice of sunlight hazardous properties; however, scientists generally were already aware that ultraviolet radiation can cloud vision and increase the risk of eye disease. Per the Baltimore Sun, about 20 million people in the United States have cataracts, and recent studies demonstrate that high levels of UV radiation from the sun can damage the eye lens and retina. Angela Brown and Delwin T. Lindsey, a husband and wife team of psychologists at Ohio State University, have been studying the effects of ultraviolet light on the eyes of people in the tropics. The high levels of sunlight in areas close to the equator create a yellowish tint in the lenses of the eyes, rendering a distorted view of certain colors. Some individuals see blue as gray or black. Because there are persons who cannot see blue, according to Brown and Lindsey, some tribal languages lack a word for the color.

Over the past 35 years, the two have studied over 200 world languages, including those in common usage such as English and French and the less well known, for instance, Mixtec spoken in remote regions of Mexico, Kwerba in Indonesia, and Chichewa in Africa. They found that in the languages of tropical tribes (namely those that receive intense amounts of sunlight), there is no word to describe the color blue. They believe that this is the result of severe damage to the eyes. The yellowing of the lenses causes some colors to appear less vibrant. According to Brown, To an eye damaged by sunlight, even a clear sky will not look blue. The condition also clouds the distinctions between blues, greens, and grays. This is not, however, to be confused with colorblindness, which derives from alterations in the color-deciphering cells in the eye. Colorblind individuals often experience difficulty distinguishing reds from greens.

Brown and Lindsey conducted an experiment in which a computer displayed 40 color samples. They asked English-speaking volunteers from tropical regions to identify each sample through a high-powered UV radiation lens. There were consistent struggles in identifying the color blue. Brown and Lindsey also used NASA technology to support this claim. Satellite images show that the highest incidence of ultraviolet radiation occurs in those places where individuals cannot identify the color blue. Because people in various cultures form languages with respect to environmental attributes, it is important to analyze the effects of high UV radiation levels on those people. The findings of these experiments were published in Psychological Science in 2002.

There is speculation regarding the credibility of this argument. Some scientists argue that several other factors such as environmental and lifestyle differences contribute to linguistic differences between cultures. Whereas the English language has eleven different categories for naming colors, other cultures have less. For instance, the Berinmo tribe of hunter-gatherers in Papua , New Guinea , has no word for blue and has five basic color terms. The Dani of Indonesia also has no word for blue and only two color terms. This does not necessarily mean, however, that the people cannot see the color. The necessity for a color-naming system may not be as great within a few tribal groups. In spite of these doubts, Brown and Lindsey will continue to research this phenomenon in hopes of reporting specific proof of its cause.