Absolute pitch

Absolute pitch (AP), widely referred to as perfect pitch, is a rare auditory phenomenon characterized by the ability of a person to identify or re-create a given musical note without the benefit of a reference tone.

AP can be demonstrated via linguistic labeling ("naming" a note), auditory imagery, or sensorimotor responses. For example, an AP possessor can accurately reproduce a heard tone on their musical instrument without "hunting" for the correct pitch. Researchers estimate the occurrence of AP to be 1 in 10,000 people.

Generally, absolute pitch implies some or all of the following abilities, achieved without a reference tone:

People may have absolute pitch along with the ability of relative pitch, and relative and absolute pitch work together in actual musical listening and practice, but strategies in using each skill vary. Those with absolute pitch may train their relative pitch, but there are no reported cases of an adult obtaining absolute pitch ability through musical training; adults who possess relative pitch but do not already have absolute pitch can learn "pseudo-absolute pitch" and become able to identify notes in a way that superficially resembles absolute pitch. Moreover, training pseudo-absolute pitch requires considerable motivation, time, and effort, and learning is not retained without constant practice and reinforcement.

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. It would have been difficult for any notion of absolute pitch to have formed earlier, because of the fluidity of pitch references. For example, the note now known as 'A' varied in different local or national musical traditions between what would now be considered as G sharp and B flat before the standardisation of the late 19th century. While the term absolute pitch, or absolute ear, was in use by the late 19th century by both British and German researchers, its application was not universal; other terms such as musical ear,absolute tone consciousness, or positive pitch 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.

Physically and functionally, the auditory system of an absolute listener does not appear to be different from a non-absolute listener. Rather, "it reflects a particular ability to analyze frequency information, presumably involving high-level cortical processing." 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. Absolute pitch may also be related to certain genes, possibly an autosomal dominant genetic trait, 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."

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Wikipedia