Absolute pitch (AP) is the rare ability to identify the pitch of a tone without the aid of a reference tone. Understanding both the nature and genesis of AP can provide insights into neuroplasticity in the auditory system. We explored factors that may influence the accuracy of pitch perception in AP subjects both during the development of the trait and in later age. We used a Web-based survey and a pitch-labeling test to collect perceptual data from 2,213 individuals, 981 (44%) of whom proved to have extraordinary pitch-naming ability. The bimodal distribution in pitch-naming ability signifies AP as a distinct perceptual trait, with possible implications for its genetic basis. The wealth of these data has allowed us to uncover unsuspected note-naming irregularities suggestive of a "perceptual magnet" centered at the note "A." In addition, we document a gradual decline in pitch-naming accuracy with age, characterized by a perceptual shift in the "sharp" direction. These findings speak both to the process of acquisition of AP and to its stability.From a commentary by Drayna in the same issue of PNAS:
Absolute pitch is an especially tantalizing trait for genetic analysis. It has an onset early in life, it occurs equally in males and females, it is highly heritable, it is rare in the population, and it appears to be nonsyndromic, that is, unassociated with other conditions. All of these features bode well for the prospects of gene finding. However, unlike most inherited neurological conditions for which affected individuals present themselves to a medical specialist, AP individuals and families have not been easily ascertained. The demonstration by Athos et al. that a web site can be an effective tool for identifying, testing, and recruiting AP subjects is an important development. The identification of the genetic variation that leads to AP is likely to tell us much about a part of the auditory system that is currently obscure, and the results of Athos et al. are indeed encouraging in this quest.