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is that this ability is available only to rare people who have a particular genetic endowment, and that it becomes manifest in these people as soon as circumstances allow. There are two general arguments for this view: First, absolute pitch general- ly appears at a very young age, and often when the child has had little or even no formal musical training; second, the
2
ability often runs in families. The problem with both of these
arguments is that there are alternative explanations in terms of very early childhood exposure—babies born into families whose members have absolute pitch would frequently be exposed to pitches in association with their names very early in life, so that they would have the opportunity to develop this ability at a very young age. Nevertheless, there is a vigor- ous, ongoing, search for a DNA marker for absolute pitch,20 though at this writing the search has so far proved unsuc- cessful.
Others have espoused the opposite view; namely that absolute pitch can be acquired by anyone at any time, given intensive practice. Indeed, on browsing the Web one encoun- ters an impressive number of offers to supply the reader with training programs for absolute pitch that are guaranteed to produce success. Unfortunately, however, these claims are
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unsupported by the scientific evidence. The one reliable
report of partial success comes from Brady22 who subjected himself to a heroic regimen in which he listened to training tapes for about 60 hours, following which he obtained a score of 65% correct on a test of absolute pitch. At best, Brady’s report underscores the extreme difficulty of acquiring absolute pitch in adulthood, in contrast with its unconscious and effortless acquisition in early childhood.
There is considerable evidence that the acquisition of absolute pitch is associated with early musical training—the earlier the musical training the stronger the association. For example, in a large scale survey, 40% of respondents who began music lessons at or before age 4 stated that they pos- sessed absolute pitch, and this percentage decreased with increasing age of onset of music lessons, so that only 3% of those who began music lessons at or after age 9 stated that they
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absolute pitch might be most readily acquired in infancy. There is an intriguing parallel between the timetables associated with the acquisition of absolute pitch on the one hand and of speech and language on the other. Lennenberg23 was perhaps the first to argue persuasively that the acquisi- tion of speech involves a critical period. Learning a second language after puberty is self-conscious and labored; and even following many years of experience, a second language that is learned in adulthood is generally spoken with a “for- eign accent.” Several lines of research have provided strong support for the critical period hypothesis, for both first and second languages. For example, children who were socially isolated early in life, and so were deprived of the opportunity to acquire speech, were unable to acquire normal language
Such findings strongly indicate that the acquisition of absolute pitch involves a critical period. Although this period is generally regarded as beginning at age 3 or so, formal musical training cannot reasonably be initiated at a younger age, which leaves open the possibility that
possessed the ability.
24 course of recovery from brain injury at different ages also
when they were later placed in a normal environment.
The
points to a critical period. The prognosis has been found to be best when the injury occurred before age 6, and very poor
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The time course for acquisition of absolute pitch, as a function of age of onset of music lessons, appears to be remarkably similar to that for second language acquisition. Although there are critical periods for the devel- opment of other functions, no other critical periods have been documented that show the same correspondence with
that for speech and language in terms of timeframe.
The case for a link between absolute pitch and speech is strengthened by consideration of tone languages, such as Mandarin, Cantonese, and Vietnamese. In these languages, words take on entirely different meanings depending on the lexical tones in which they are enunciated, with tones being defined both by their pitch heights (or registers) as well as by their pitch contours. (In Beijing Mandarin, for example, the first tone is high and level, the second is mid-high and rising, the third is low and initially falling and then rising, and the fourth is high and falling.) This contrasts with intonation languages such as English, in which pitch is employed to con- vey prosody and emotional tone, but is not involved in deter- mining the meaning of individual words. For example, in Mandarin the word “ma” when spoken in the first tone means “mother,” in the second tone means “hemp,” in the third tone means “horse,” and in the fourth tone means a reproach. So pitches in such languages are used to create ver- bal features, analogous to consonants and vowels. Therefore when speakers of Mandarin hear the word “ma” spoken in the first tone and attribute the meaning “mother,” or when they hear “ma” spoken in the third tone and attribute the meaning “horse,” they are associating a pitch—or a series of pitches—with a verbal label. Analogously, when people with absolute pitch identify the sound of the note F# as “F#,” or the note B as “B” they are also associating a pitch with a meaning,
or a verbal label.
As a further argument that absolute pitch in tone lan-
guages may be packaged with other features of speech, the brain structures responsible for processing lexical tone have been shown to overlap with those involved in processing phonemes (i.e., vowels and consonants). For example, while the communication of prosodic features of language appears to be a function of the non-dominant hemisphere (i.e., the right hemisphere in most right-handers) for speakers of both tone and intonation languages,27,28 the processing of lexical tone appears to be a function of the dominant hemisphere
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In other studies it was found that individuals who were given the opportunity to learn a second language in early childhood became most proficient in this language, with proficiency declining with increasing age of initial expo- sure to the second language, reaching a plateau with initial
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after puberty.
exposure in adulthood.
(i.e., the left hemisphere in most right-handers).
So when
speakers of tone language perceive pitches and pitch contours
as signifying meaningful words, circuitry in the dominant
hemisphere is involved. Given the evidence on critical peri-
ods for the acquisition of speech, we can then hypothesize
that such circuitry is developed very early in life, during the
period in which infants acquire other features of their native
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language. If the opportunity to form such associations is
unavailable during this critical period, these associations
Enigma of Absolute Pitch 13