Absolute pitch (AP), widely referred to as perfect pitch, is the ability of a person to identify or re-create a given musical note without the benefit of an external reference.

Definition

Absolute pitch (AP), or perfect pitch, is the ability to name or reproduce a tone without reference to an external standard.^[1]

The naming/labeling of notes need not be verbal. AP can also be demonstrated by other codes such as auditory imagery or sensorimotor responses, for example, reproducing a tone on an instrument. Therefore a musician from an aural tradition, with no musical notation, can still exhibit AP when asked to reproduce a sounded note.^[2][3]

Possessors of absolute pitch exhibit the ability in varying degrees. Generally, absolute pitch implies some or all of the following abilities when done without reference to an external standard:^[4]

• Identify by name individual pitches (e.g. A, B, C♯) played on various instruments
• Name the key of a given piece of tonal music just by listening (without reference to an external tone)
• Identify and name all the tones of a given chord or other tonal mass
• Accurately sing a given pitch without an external reference
• Name the pitches of common everyday noises such as car horns
• Identify the numerical value in hertz of a given note.

Individuals may possess both absolute pitch and relative pitch ability in varying degrees. Both relative and absolute pitch work together in actual musical listening and practice, although individuals exhibit preferred strategies in using each skill.^[5]

Scientific studies

History of study and terminologies

Scientific study of absolute pitch appears to have commenced in the 19th century, focusing on the phenomenon of musical pitch and methods of measuring it.^[6] While the term absolute pitch, or absolute ear, was in use by the late 19th century by both English^[7] and German researchers,^[8] its application was not universal; other terms such as musical ear,^[6] absolute tone consciousness,^[9] or positive pitch^[10] were also used to refer to the ability. The skill is not exclusively musical, or limited to human perception; absolute pitch has been demonstrated in animals such as bats, wolves, gerbils, and birds, for whom specific pitches facilitate identification of mates or meals.^[11]

Difference in cognition, not elementary sensation

Physically and functionally, the auditory system of an absolute listener does not appear to be measurably different from a non-absolute listener.^[12] Rather, "AP perception is not dependent on a special kind of ear; it reflects a particular ability to analyze frequency information, presumably involving high-level cortical processing."^[13] Absolute pitch is an act of cognition, needing memory of the frequency, a label for the frequency (such as "B-flat"), and exposure to the range of sound encompassed by that categorical label. Absolute pitch may be directly analogous to recognizing colors, phonemes (speech sounds) or other categorical perception of sensory stimuli. Just as most people have learned to recognize and name the color blue by the frequencies of the electromagnetic radiation that is perceived as light, it is possible that those who have been exposed to musical notes together with their names early in life will be more likely to identify, for example, the note C.^[14] Absolute pitch may also be related to certain genes, possibly an autosomal dominant genetic trait,^[15][16] though it "might be nothing more than a general human capacity whose expression is strongly biased by the level and type of exposure to music that people experience in a given culture."^[17]

Influence by music experience

Absolute pitch sense appears to be influenced by cultural exposure to music, especially in the familiarization of the equal-tempered C-major scale. Most of the absolute listeners that were tested in this respect identified the C-major tones more reliably and, except for B, more quickly than the five "black key" tones,^[18] which corresponds to the higher prevalence of these tones in ordinary musical experience. One study of Dutch non-musicians also demonstrated a bias toward using C-major tones in ordinary speech, especially on syllables related to emphasis.^[19]

Linguistics

Absolute pitch is more common among speakers of tonal languages such as most dialects of Chinese or Vietnamese, which depend heavily on pitch variation across single words for lexical meaning (ex. Mandarin with four possible pitch variations, Cantonese with six or seven, Minnan with seven or eight (depending on dialect), and Vietnamese with six.)^[20][21] Speakers of Sino-Tibetan languages have been reported to speak a word in the same absolute pitch (within a quarter-tone) on different days; it has therefore been suggested that absolute pitch may be acquired by infants when they learn to speak in a tonal language^[22] (and possibly also by infants when they learn to speak in a pitch stress language). However, the brains of tonal-language speakers do not naturally process musical sound as language;^[23] perhaps such individuals may be more likely to acquire absolute pitch for musical tones when they later receive musical training. Also many native speakers of a tone language, even those with little musical training, are observed to sing the same piece in the same key consistently. Among music students of East Asian ethnic heritage, those who speak a tone language very fluently have a much higher prevalence of absolute pitch than those who speak only nontone language.^[24][25]

It is possible that level-tone languages which are found in Africa—such as Yoruba,^[26] with three pitch levels, and Mambila,^[27] with four—may be better suited to study the role of absolute pitch in speech than the pitch and contour tone languages of East Asia.

Further, speakers of European languages have been found to make use of an absolute, though subconscious, pitch memory when speaking.^[28]

Perception

Absolute pitch is the ability to perceive chroma and to mentally categorize sounds according to perceived chroma.^[29] Chroma is a tonal quality which recurs among tones which share the relationship of an octave. While the boundaries of musical pitch categories vary among human cultures, the recognition of octave relationships is a natural characteristic of the mammalian auditory system.^{[30][31][32][33][34][35]} Accordingly, absolute pitch is not the ability to estimate a pitch value from the dimension of pitch evoking frequency (30–5000 Hz),^[14] but to identify a chroma category within the dimension of pitch class (e.g., C-C♯-D ... B-C).

An absolute listener's sense of hearing is typically no keener than that of a non-absolute ("normal") listener.^[36] Absolute pitch does not depend upon a refined ability to perceive and discriminate gradations of sound frequencies;^[37] furthermore, the tasks of identification (recognizing and naming a pitch) and discrimination (detecting changes or differences in rate of vibration) are accomplished with different brain mechanisms.^[38]

Genetics and absolute pitch

The prevalence of absolute pitch is considerably higher among individuals with early childhood in East Asia.^{[39][40][41][42]} While this difference might seem to be genetic in origin;^[43] individuals of East Asian ancestry who are born or reared in the United States or Canada are significantly less likely to develop absolute pitch than those raised in East Asia.^[42] This presents the likelihood that the difference is explained by cultural experience rather than genetic heritage. Language may be an important factor; many East Asians speak tonal languages such as Mandarin and Cantonese, while others (such as those in Japan and certain provinces of Korea) speak pitch accent languages, and the prevalence of absolute pitch may be partly explained by exposure to pitches together with meaningful musical labels very early in life.^{[40][41][42][44]}

Nature vs. nurture

Many people have believed that musical ability itself is an inborn talent.^[10] Some scientists currently believe absolute pitch may have an underlying genetic basis and are trying to locate genetic correlates;^[45] while evidence suggesting a genetic locus has recently arisen,^[46] most believe that the acquisition of absolute pitch requires early training during a critical period of development, regardless of whether a genetic predisposition toward development exists.^[47] The "unlearning theory", first proposed by Otto Abraham,^[48] has recently been revived by developmental psychologists who argue that every person possesses absolute pitch (as a mode of perceptual processing) as an infant, but that a shift in cognitive processing styles (from local, absolute processing to global, relational processing) causes most people to unlearn it; or, at least, causes children with musical training to discard absolute pitch as they learn to identify musical intervals.^[49] Additionally, any nascent absolute pitch may be lost simply by the lack of reinforcement or lack of clear advantages in most activities in which the developing child is involved. An unequivocal resolution to the ongoing debate would require controlled experiments that are both impractical and unethical.

Researchers have been trying to teach absolute pitch ability for more than a century,^[50] and various commercial absolute-pitch training courses have been offered to the public since the early 1900s.^[51] No adult has ever been documented to have acquired the ability,^[52] as all adults who have undergone AP training have failed, when formally tested, to show "an unqualified level of accuracy... comparable to that of AP possessors".^[53]

For children aged 2–4, observations have suggested a certain method of music education^[54] may be successful in training absolute pitch,^[55] but the same method has also been shown to fail with students 5 years and older.^[56]

Pitch memory related to musical context

While very few people have the ability to name a pitch with no external reference, pitch memory can be activated by repeated exposure. People who are not skilled singers will often sing popular songs in the correct key,^[57] and can usually recognize when TV themes have been shifted into the wrong key.^[58] Members of the Venda culture in South Africa also sing familiar children's songs in the key in which the songs were learned.^[59]

This phenomenon is apparently unrelated to musical training. The skill may be associated more closely with vocal production. Violin students learning the Suzuki method are required to memorize each composition in a fixed key and play it from memory on their instrument, but they are not required to sing. When tested, these students did not succeed in singing the memorized Suzuki songs in the correct key.^[60]

Possible problems

People who have absolute pitch may feel irritated when a piece is transposed to a different key or played at a nonstandard pitch.^[61] Musicians with absolute pitch may fail to develop relative pitch skills when following standard curricula, conceptualizing music as a sequence of absolute tones instead; it thus becomes difficult for them to transpose or play a transposing instrument.^[62] They may also not be able to continue playing or singing with a group when the pitch drops, or with an orchestra that is not tuned to standard concert pitch A4 = 440 Hz (variable); this may be due to a perception of pitch which is categorical rather than freely adjustable.^[63]

Special populations

The prevalence of absolute pitch is higher among those who are blind from birth as a result of optic nerve hypoplasia, and it has been claimed that it is higher among those with Williams Syndrome^[64] and those with an autism spectrum disorder.^[65][66]

Correlation with musical talent

Absolute pitch is not a prerequisite for developing a high level of talent as a musician or composer, and musicians may disagree about the overall value and relevance of absolute pitch ability to musical experience. Owing to uncertainty in the historical record, and, until recently, lack of objective tests, it is often impossible to determine whether notable composers and musicians had absolute pitch or not. Since absolute pitch is rare in European musical culture,^[41] claims that any particular musician possessed it are to be doubted, unless there is clear contemporary evidence. Among composers of the Baroque and Classical eras, such evidence is available only for Mozart's perfect pitch. He famously attained it at the age of 3.^[67] Experts have only surmised that Beethoven had it, merely due to his remarkable ability to compose undetrimented music long after becoming completely deaf. For 19th-century musicians such as Camille Saint-Saëns and John Philip Sousa, it became more common for the presence of absolute pitch to be recorded.^{[citation needed]} Nicolas Slonimsky was discovered to have perfect pitch as a child of six, which led to him being given music lessons by his aunt Isabelle Vengerova, and a life as a musician. He even titled his 1988 autobiography Perfect Pitch: A Life Story (ISBN 0-19-315155-3). The same was the case with jazz pianist Keith Jarrett, starting with his parents discovering his ability to reproduce musical lines on the piano at the age of three.^[68]

Relative pitch

Many musicians have quite good relative pitch, a skill which can be learned. With practice, it is possible to listen to a single known pitch once (from a pitch pipe or a tuning fork) and then have stable, reliable pitch identification by comparing the notes heard to the stored memory of the tonic pitch.^[69] Unlike absolute pitch, this skill is dependent on a recently perceived tonal center.

See also

• Ear training
• Tonal memory
• Synesthesia

References

External links

• Online absolute pitch survey and test with information about the absolute pitch study conducted at the University of California-San Francisco
• Comprehensive historical bibliography of absolute pitch research, 1876–present
• Another bibliography of absolute pitch, with +300 papers