|a broken and fallen note|
According to scientists who study tone deafness, about 5% of people have a significant handicap in hearing and learning music. The root disability appears to be a difficulty in distinguishing different pitches. The smallest step of the Western scale is the half step, one-twelfth of an octave. (Indian music uses smaller units of pitch change.) People with amusia have difficulty distinguishing differences as small as that half-step, although they may hear much larger pitch differences accurately, sort of like being able to see the largest letters on an eye chart.
Perhaps about half of those with tone deafness also have difficulty hearing rhythm in music. They're lousy dancers and even falter in tapping along in time to the music. They also have impaired memory for music. They are only half as good as other people in naming a familiar tune. Often they recognize a song by its lyrics instead of its melody. Even when they try to memorize a stretch of music, they have difficulty recognizing it when an examiner later plays it back to them. Although most tone deaf people can tell if a piece of music is meant to be happy or sad, many don't particularly enjoy music, and some find hearing it actually painful.
Interestingly, the disability in amusia appears limited to music. Tone deaf people have little difficulty recognizing intonation in speech. For example, the difference between a question and a statement is often only a difference in pitch at the end of a sentence. (Think of "You're coming," versus "You're coming?") These differences are large enough that most tone deaf people have no difficulty with them. (However, I'm not aware of any research on how well tone deaf people learn tonal languages such as Chinese.)
In my latest fantasy novel, THE ICE CASTLE: An Adventure in Music, tone deaf people are relegated to the lowest ranks of society. Ivan, one of the protagonists, difficulty distinguishing musical pitches, but through careful and attentive listening, he gradually improves over the course of the story. Such improvement may not happen with the most severely tone deaf, who even after growing up in a music-rich environment or taking music lessons in childhood show no improvement.
I'm fascinated by tone deafness because I fall pretty clearly into that range myself. My elementary school singing teacher urged me to sing softly or only mouth the words in school performances, but it wasn't just a matter of not singing well. My father told me that when I was young, if he played two notes on the piano and asked me which was higher, I couldn't tell the answer. I remember lying in bed on Wednesday nights listening to his madrigal group sing, trying to figure out from the beat whether the song might be one I "knew," like "Yankee Doodle" (a song which, I later learned, madrigal groups sing very rarely).
Gradually, as I got older, the condition's severity lessened. I took piano lessons for a couple of years, and in high school, where I played the clarinet, I finally learned enough to be able to tell when I hit a wrong note.
Around high school I realized that one reason it was difficult for me to appreciate orchestral music is that I couldn't grasp the idea of musical "theme." I could never remember previous phrases well enough to notice when they returned with variations. In listening to unfamiliar music, I was condemned to a perpetual present. It was like trying to read a novel when the characters are always someone you just met.
I did learn, however, that with careful listening, I can more or less blend in with other singers. With lots and lots of repetition, I can even carry a few phrases of a simple tune on my own. Even as young children, my kids, all of whom grew up to be fine singers, sometimes asked me to stop singing. I still can't hear when a song on the radio changes key, and I often can't identify a familiar song until the lyrics start. If I lived in a society where musical intelligence mattered as much as verbal and logical intelligence, I'd be classified as subnormal. Exploring such a world, where tone deafness is an unsurmountable social handicap, furnished a big part of my motivation for writing THE ICE CASTLE.