Musicophilia: Tales of Music and the Brain (15 page)

When people with absolute pitch “hear a familiar piece of music played in the wrong key,” Daniel Levitin and Susan Rogers write, “they often become agitated or disturbed…. To get a sense of what it is like, imagine going to the produce market and finding that, because of a temporary disorder of visual processing, the bananas all appear orange, the lettuce yellow and the apples purple.”

Transposing music from one key to another is something which any competent musician can do easily and almost automatically. But for someone with absolute pitch, each key has its own unique character, and the key in which one has always heard a piece is likely to be felt as the only right one. Transposing a piece of music, for someone with absolute pitch, can be analogous to painting a picture with all the wrong colors.

Another difficulty was mentioned to me by the neurologist and musician Steven Frucht, who himself has absolute pitch. He sometimes experiences a certain difficulty in hearing intervals or harmonies because he is so conscious of the chroma of the notes that compose them. If, for example, one plays a C on the piano and the F-sharp above this, he might be so conscious of the C-ness of the C and the F-sharpness of the F-sharp that he fails to notice that they form a tritone, a dissonance which makes most people wince.
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Absolute pitch is not necessarily of much importance even to musicians— Mozart had it, but Wagner and Schumann lacked it. But for anyone who has it, the loss of absolute pitch may be felt as a severe privation. This sense of loss was clearly brought out by one of my patients, Frank V., a composer who suffered brain damage from the rupture of an aneurysm of the anterior communicating artery. Frank was highly gifted musically, and had been musically trained since the age of four. He had had absolute pitch as long as he could recall, but now, he said, “it is gone, or it has certainly been eroded.” Since absolute pitch was of advantage to him as a musician, he felt its “erosion” keenly. Originally, he said, he perceived pitches instantly, absolutely, as he perceived colors— no “mental process” was involved, no inference, no reference to other pitches or intervals or scales. This form of absolute pitch had vanished completely; it was, he said, as if he had become “colorblind” in this regard. But as he convalesced from his brain injury, he found that he still possessed reliable pitch memories of certain pieces and certain instruments, and he could use these reference points to infer other pitches— though this, in comparison to his “instant” absolute pitch, was a slower process.

It was also, subjectively, entirely different, for previously every note and every key had had a distinctive flavor for him, a character uniquely its own. Now all of this was gone, and there was no longer any real difference, for him, between one key and another.
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I
T SEEMS CURIOUS,
in a way, that absolute pitch is so rare (it is estimated as occurring in less than one person in ten thousand). Why don’t all of us hear “G-sharpness” as automatically as we see blue or smell a rose? “The real question concerning absolute pitch,” wrote Diana Deutsch et al. in 2004, “…is not why some people possess it, but rather why it is not universal. It is as though most people have a syndrome with respect to the labeling of pitches which is like color anomia, in which the patient can recognize colors, and discriminate between them, but cannot associate them with verbal labels.”

Deutsch speaks here from personal experience as well. As she wrote to me in a recent letter:

Absolute pitch is of special interest because it exemplifies a whole other realm of perception, of qualia, something which most of us cannot even begin to imagine; because it is an isolated ability with little inherent connection to musicality or anything else; and because it shows how genes and experience can interact in its production.

It has long been clear anecdotally that absolute pitch is commoner in musicians than in the general public, and this has been confirmed by large-scale studies. Among musicians, absolute pitch is commoner in those who have had musical training from an early age. But the correlation does not always hold: many gifted musicians fail to develop absolute pitch, despite intensive early training. It is commoner in certain families— but is this because of a genetic component or because some families provide a richer musical environment? There is a striking association of absolute pitch with early blindness (some studies estimate that about 50 percent of children born blind or blinded in infancy have absolute pitch).

One of the most intriguing correlations occurs between absolute pitch and linguistic background. For the past few years, Diana Deutsch and her colleagues have studied such correlations in greater detail, and they observed in a 2006 paper that “native speakers of Vietnamese and Mandarin show very precise absolute pitch in reading lists of words” most of these subjects showed variation of a quarter tone or less. Deutsch et al. have also showed very dramatic differences in the incidence of absolute pitch in two populations of first-year music students: one at the Eastman School of Music in Rochester, New York, and the other at the Central Conservatory of Music in Beijing. “For students who had begun musical training between ages 4 and 5,” they wrote, “approximately 60% of the Chinese students met the criterion for absolute pitch, while only about 14% of the US nontone language speakers met the criterion.” For those who had begun musical training at age six or seven, the numbers in both groups were correspondingly lower, about 55 percent and 6 percent. And for students who had begun musical training later still, at age eight or nine, “roughly 42% of the Chinese students met the criterion while none of the US nontone language speakers did so.” There were no differences between genders in either group.

This striking discrepancy led Deutsch et al. to conjecture that “if given the opportunity, infants can acquire AP as a feature of speech, which can then carry over to music.” For speakers of a nontonal language such as English, they felt, “the acquisition of AP during music training is analogous to learning the tones of a second language.” They observed that there was a critical period for the development of absolute pitch, before the age of eight or so— roughly the same age at which children find it much more difficult to learn the phonemes of another language (and thus to speak a second language with a native accent). Deutsch et al. suggested, therefore, that all infants might have the potential for acquiring absolute pitch, which could perhaps be “realized by enabling infants to associate pitches with verbal labels during the critical period” for language acquisition. (They did not exclude the possibility, nonetheless, that genetic differences might be important, too.)

The neural correlates of absolute pitch have been illuminated by comparing the brains of musicians with and without absolute pitch using a refined form of structural brain imaging (MRI morphometry), and by functional imaging of the brain as subjects identify musical tones and intervals. A 1995 paper by Gottfried Schlaug and his colleagues showed that in musicians with absolute pitch (but not musicians without), there was an exaggerated asymmetry between the volumes of the right and left planum temporale, structures in the brain that are important for the perception of speech and music. Similar asymmetries in the size and activity of the planum temporale have been shown in other people with absolute pitch.
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Absolute pitch is not just a matter of pitch perception. People with absolute pitch must be able not only to perceive precise pitch differences, but to label them, to line them up with the notes or names of a musical scale. It is this ability which Frank V. lost with the frontal lobe damage caused by the rupture of his cerebral aneurysm. The additional cerebral mechanisms required to correlate pitch and label are in the frontal lobes, and this, too, can be seen in functional MRI studies; thus, if someone with absolute pitch is asked to name tones or intervals, MRIs will show focal activation in certain associative areas of the frontal cortex. In those with relative pitch, this region is activated only when naming intervals.

While such categorical labeling is learned by all people with absolute pitch, it is not clear that this excludes a prior
categorical
perception of pitch that is not dependent on association and learning. And the insistence of many with absolute pitch on the unique perceptual qualities of every pitch— its “color” or “chroma”— suggests that before the learning of categorical labels, there may be a purely perceptual categorization.

Jenny Saffran and Gregory Griepentrog at the University of Wisconsin compared eight-month-old infants to adults with and without musical training in a learning test of tone sequences. The infants, they found, relied much more heavily on absolute pitch cues; the adults, on relative pitch cues. This suggested to them that absolute pitch may be universal and highly adaptive in infancy but becomes maladaptive later and is therefore lost. “Infants limited to grouping melodies by perfect pitches,” they pointed out, “would never discover that the songs they hear are the same when sung in different keys or that words spoken at different fundamental frequencies are the same.” In particular, they argued, the development of language necessitates the inhibition of absolute pitch, and only unusual conditions enable it to be retained. (The acquisition of a tonal language may be one of the “unusual conditions” that lead to the retention and perhaps heightening of absolute pitch.)

Deutsch and her colleagues, in their 2006 paper, suggested that their work not only has “implications for the issues of modularity in the processing of speech and music…[but] of the evolutionary origin” of both. In particular, they see absolute pitch, whatever its subsequent vicissitudes, as having been crucial to the origins of both speech and music. In his book
The Singing Neanderthals: The Origins of Music, Language, Mind and Body,
Steven Mithen takes this idea further, suggesting that music and language have a common origin, and that a sort of combined protomusic-cum-protolanguage was characteristic of the Neanderthal mind.
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This sort of singing language of meanings, without individual words as we understand them, he calls Hmmm (for holistic-mimetic-musical-multimodal)— and it depended, he speculates, on a conglomeration of isolated skills, including mimetic abilities and absolute pitch.

With the development of “a compositional language and syntactic rules,” Mithen writes, “allowing an infinite number of things to be said, in contrast to the limited number of phrases that Hmmm allowed…the brains of infants and children would have developed in a new fashion, one consequence of which would have been the loss of perfect pitch in the majority of individuals, and a diminution of musical abilities.” We have little evidence as yet for this audacious hypothesis, but it is a tantalizing one.

I was once told of an isolated valley somewhere in the Pacific where all the inhabitants have absolute pitch. I like to imagine that such a place is populated by an ancient tribe that has remained in the state of Mithen’s Neanderthals, with a host of exquisite mimetic abilities and communicating in a protolanguage as musical as it is lexical. But I suspect that the Valley of Absolute Pitch does not exist, except as a lovely, Edenic metaphor, or perhaps some sort of collective memory of a more musical past.

D
arwin saw the eye as a miracle of evolution; the ear, in its way, is just as complex and beautiful. The path taken by sound vibrations, from their entrance into the external ear canals, through the eardrums on either side to the tiny bones, the ossicles, of the middle ear, to the snail-shaped cochlea, was first worked out in the seventeenth century. It was suggested then that sounds were transmitted by the ear, becoming amplified in the cochlea “as in a musical instrument.” A century later, it was discovered that the tapered shape of the cochlear spiral was differentially tuned to the range of audible frequencies, receptive to low sounds at its broad base, high sounds at its narrow apex. By 1700 it was realized that the cochlea was filled with fluid and lined with a membrane that was conceived as a series of vibrating strings, a resonator. In 1851, Alfonso Corti, an Italian physiologist, discovered the complex sensory structure that we now call the organ of Corti, lying on the basilar membrane of the cochlea and containing about thirty-five hundred inner hair cells, the ultimate auditory receptors. A youthful ear can hear ten octaves of sound, spanning a range from about thirty to twelve thousand vibrations a second. The average ear can distinguish sounds a seventeenth of a tone apart. From top to bottom, we hear about fourteen hundred discriminable tones.