Absolute pitch, popularly known as "perfect pitch," is the ability to name or produce a musical note of particular pitch without benefit of a reference note. It is extremely rare in the U.S. and Europe, with an estimated prevalence of less than one in 10,000. This rarity has so far been unexplained. We here report the first large-scale study comparing the prevalence of absolute pitch in two normal populations by means of a direct test. Our findings suggest that the potential for acquiring absolute pitch may be universal at birth. It raises the possibility that parents may be able to encourage the development of absolute pitch in their children during the "critical period" when infants are learning the main features of their native language.

Our new results follow up on a 1999 study, in which some of us made a startling discovery while exploring the realm of language rather than music.  The 1999 study tested native speakers of two tone languages, Mandarin and Vietnamese.  In tone languages, words get their meaning in part from the pitches in which the vowels are pronounced. (In Mandarin, for example, the word "ma" means "mother" when spoken in the first tone, "hemp" in the second tone, "horse" in the third tone and a reproach in the fourth tone.) The study found that Mandarin and Vietnamese speakers displayed a remarkably precise and stable form of absolute pitch in reciting lists of words ^{1, 2}. Based on these findings, we proposed that absolute pitch originated in human history as a feature of speech.  We further proposed that tone language speakers naturally acquire this feature in the first year of life, during the period in which infants acquire other features of their native language ^{3, 4}.  On this line of reasoning, absolute pitch for music might then be acquired by tone language speakers in the same way as they would acquire the pitches of a second tone language. We might therefore expect to find a much higher prevalence of absolute pitch for music among tone language speakers than among speakers of nontone languages such as English⁵.

In this, the first large-scale study in which the prevalence of absolute pitch in normal populations was compared using a direct test, we examined the prevalence of absolute pitch in two groups of music students.  The first group consisted of 88 first year students who were enrolled in a required course at the prestigious Central Conservatory of Music in Beijing (CCOM), China. These were 28 male and 60 female, with an average age of 20 (range 17-34) yrs. All these subjects spoke the tone language Mandarin.  The second group consisted of 115 first-year students who were enrolled in a required course at the renowned Eastman School of Music (ESM) in Rochester, New York, and who were nontone language speakers, with both parents being nontone language speakers. These were 54 male and 61 female, with an average age of 19 (range 17-23) years. All students who were invited to take the test agreed to do so; there was therefore no self-selection of subjects from within either group.  The test was administered to the two groups under very similar conditions.

Our test for absolute pitch consisted of the 36 notes spanning the 3-octave range beginning on the C below Middle C. The notes were piano tones generated on a Kurzweil synthesizer. All intervals between successive notes were larger than an octave, to minimize the use of relative pitch (a more common musical ability in which listeners can name notes after hearing a reference note). The following sound example presents a brief test designed as in the experiment.

Click here (MP3 file) to listen to the brief test.

Click here to view the answers.

Figure 1. Percentages of subjects who obtained a score of at least 85% correct on the test of absolute pitch, as a function of age of onset of musical training.   CCOM: The Central Conservatory of Music, Beijing, China. All these subjects spoke the tone language Mandarin.  ESM: Eastman School of Music, Rochester, U.S.A. All these subjects were nontone language speakers. The two groups were subdivided by age of onset of musical training 6. These were: CCOM: ages 4-5, n = 43; ages 6-7, n = 22; ages 8-9, n = 12. ESM: ages 4-5,  n = 21; ages 6-7, n = 31; ages 8-9; n = 24; ages 10-11; n = 20; ages 12-13, n = 9.

Figure 1 shows the percentages of subjects who obtained a score of at least 85% correct on the test of absolute pitch, as a function of the age at which they had begun taking music lessons. It can be seen that both groups, US nontone language speakers and Chinese Mandarin speakers, showed orderly effects of age of onset of musical training: The earlier that an individual had begun musical training, the higher that person's probability of meeting the criterion for absolute pitch. However, the prevalence of absolute pitch was strikingly higher among the CCOM than the ESM group. For students who had begun musical training between ages 4 and 5, 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 students beginning musical training between ages 6 and 7, approximately 55% of the Chinese students met the criterion, whereas this was true of only about 6% of the US. nontone language speakers. For those who had begun musical training between ages 8 and 9, roughly 42% of the Chinese students met the criterion whereas none of the US nontone language speakers did so. There were no  differences depending on gender, in either group or any subgroup.

Figure 2. Percentages of subjects who obtained a score of at least 85% correct on the test of absolute pitch, allowing for semitone errors, as a function of age at which they began musical training.  CCOM: The Central Conservatory of Music, Beijing, China. All these subjects spoke the tone language Mandarin.  ESM: Eastman School of Music, Rochester, U.S.A. All these subjects were nontone language speakers. The two groups were subdivided by age of onset of musical training6. These were: CCOM: ages 4-5, n = 43; ages 6-7, n = 22; ages 8-9, n = 12. ESM: ages 4-5, n = 21; ages 6-7, n = 31; ages 8-9; n = 24; ages 10-11; n = 20; ages 12-13, n = 9.

Figure 2 shows the percentages of subjects who obtained a score of at least 85% on the same test, allowing for semitone errors (that is, the students were given credit for correct answers even if they missed the note by a semitone; for example, answering C when the correct answer was C sharp). It can be seen that here the difference between the two groups was even more extreme.  For students who had begun musical training between ages 4 and 5, approximately 74% of the Chinese students met the criterion, whereas only about 14% of the U.S. nontone language speakers did so. And of those who had begun musical training between ages 6-7, roughly 68% of the Chinese students met the criterion, whereas this was true of only about 10% of the US nontone language speakers. Again, there were no differences depending on gender in either group or subgroup.

The striking difference between the CCOM and ESM groups found here supports the conjecture that, if given the opportunity, infants can acquire absolute pitch as a feature of speech, which can then carry over to music. Indeed, the plots shown here for the acquisition of absolute pitch in speakers of tone and nontone languages reflect a very similar picture, in terms of timeframe, to the developmental "critical periods" inferred by linguists for the acquisition of first and second languages respectively. Other studies have shown that it is exceedingly difficult to learn a first language if the person has been deprived of the opportunity to do so in infancy or early childhood. It also becomes increasingly more difficult to learn a second language as the age of initial exposure to this language increases, through childhood and adolescence ⁷. We hypothesize that, for speakers of tone languages, the acquisition of absolute pitch during musical training is analogous to learning the tones of a second language. Speakers of nontone languages such as English, who do not have the opportunity to associate pitches with meaningful words in infancy, are therefore at a disadvantage for the acquisition of absolute pitch, compared with speakers of tone languages such as Mandarin.

It may alternatively be hypothesized that the differences between the two groups found here are due to dissimilarities in brain structure⁸ which might be genetically determined⁹. Indeed, both critical period and genetic factors might be involved. At all events, this paper reports the first large scale study which demonstrates a difference in the prevalence of absolute pitch in two normal populations, as determined by the administration of a direct, on-site test, without self-selection from within the target populations, and controlling for gender and for age of onset of musical training¹⁰.

If you'd like to listen to a full test designed as for the study, and then view the answers, click here.

References and Footnotes

1.     Deutsch, D., Henthorn, T., & Dolson, M. Absolute pitch is demonstrated in speakers of tone languages. Journal of the Acoustical Society of America, 106, 2267 (1999).

2.     Deutsch, D., Henthorn, T. & Dolson, M. Absolute pitch, speech, and tone language: Some experiments and a proposed framework. Music Perception, 21, 339-356 (2004).

3.     Kuhl, P.,  Williams, K.,  Lacerda, F.,  Stevens, K., & Lindblom, B. Linguistic experience alters phonetic perception in infants by 6 months of age. Science, 255, 606-608  (1992).

4.     Saffran J.R. & Griepentrog G.J. Absolute pitch in infant auditory learning: Evidence for developmental reorganization. Developmental Psychology,  37, 74-85 (2001).

5. On this hypothesis, the rare occurrences of absolute pitch in nontone language speakers are due to a critical period of unusually long duration, so that it extends to the age at which the child can take music lessons.

6.     In order to make meaningful comparisons, we considered only those subgroups that contained at least nine subjects.

7.     Newport, E. L. Maturational constraints on language learning. Cognitive Science, 14, 11-28 (1990).

8.     Schlaug, G., Jaencke, Huang, Y., & Steinmetz, H. In vivo evidence of structural brain asymmetry in musicians. Science, 267, 699-701 (1995).

9.     Gregersen,  P. K., Kowalksy, E., Kohn, N. & Marvin, E.W. Absolute pitch: prevalence, ethnic variation, and estimation of the genetic component. American Journal of Human Genetics,  65, 911-913 (1999).

10.  We thank Zhou Haihong, Zhang Zheng-sheng, Steve Laitz, William Marvin, C. Harris, Kamil Hamaoui, and D. Bosnjakovic for help in different phases of the study.