Why can most people remember a color, but only a few can remember pitch?
—David Hardie, Perth, Australia
Robert O. Duncan, a behavioral scientist at York College, the City University of New York, responds: Although most of us believe we are better at identifying colors than sounds, our ability to identify the exact frequency of light associated with a color is actually no better than our ability to name a pitch.
Our perception of visible light depends on context. You might go shopping for house paints, for example, and be shocked to find that the particular shade of white you selected in the store makes your kitchen look pink! You may have chosen the wrong shade of white because the ambient light in the store differs from that of your home. If we could accurately identify colors, we would never make such mistakes. People may think they are more adept at identifying colors, however, because they tend to associate hues with specific objects, which do not change. For instance, we will generally perceive an apple to be red because the light reflecting off its surface remains fairly constant from moment to moment.
In contrast, in hearing we identify objects, people and speech by the changes in frequency. For example, we can understand a sentence whether it is spoken by a girl with a high voice or a man with a low voice because the relative changes in frequency that occur as the girl and man recite the same words are about the same. In fact, speech and other sounds in the environment are always changing, which is likely why we have evolved to recognize changes in frequencies rather than any single pitch.
Although few people develop perfect pitch—the ability to precisely name the frequency of a sound—we have a remarkable ability to discriminate among different sounds. We can distinguish house cats from tigers, bicycles from motorcycles, and basketballs from Ping-Pong balls. We use the melodic properties of speech to discriminate a person’s gender, identity and mood. We have an expansive musical memory that enables us to recall tens of thousands of melodies with ease. And with a modest degree of training, most musicians can develop relative pitch, the ability to identify an unknown tone in relation to a known tone.