24. September 2019

Perception of pitch is culturally influenced

Wahrnehmung von Tonhöhen ist kulturell geprägt

Forschungsleiter Nori Jacoby während seiner Studie mit Tsminane in Bolivien (Bild:Josh McDermott).

A team of researchers led by Nori Jacoby of the Max Planck Institute for Empirical Aesthetics and Josh McDermott of MIT studied pitch perception of both Westerners and the Tsimane’, an indigenous group living in the Bolivian Amazon. They discovered cross-cultural similarity and variability in two features of pitch that are well documented in Western participants: the breakdown of pitch perception at very high frequencies and octave equivalence.

The components of pitch perception

The breakdown of pitch pertains to the fact that even though the human ear can hear tones up to about 20 kHz, the perception of pitch becomes inaccurate at about 4 kHz. This property is usually associated with a biological constraint on frequency encoding originating from “phase locking,” the tendency of neuronal activity in the ear to follow tones with low but not high frequencies. The upper limit of pitch could also be an artifact of Western music, in which almost all instruments have tones that are not much higher than 4 kHz.

Octave equivalence is a prominent feature of Western music, where notes separated by an octave are given the same note name (e.g “C”). Octaves have acoustic correlates: for example if two strings have the same tension and one string is twice as long it will sound an octave below. It remains ambiguous, however, whether the experience of octave equivalence has biological origins or arises from experience with Western music, mainly because octave equivalence has thus far been solely studied with participants with extensive exposure to Western music.

Pattern of cross cultural similarity and difference

In this study, Jacoby and McDermott developed a novel method to study pitch representation cross-culturally by asking participants to sing back short melodies. The melodies were composed of high frequency tones, well above the singing range. Although their own musical instruments tended to have a relatively limited range, the researchers found that Tsimane’ listeners could reproduce pitches up to about 4 kHz very well. However, like Western listeners, their perceptions tended to deteriorate above that threshold. This finding supports the claim that the limits of pitch perception stem from biological origins.

With respect to octave equivalence, Western participants, especially those with extensive musical experience, often produced a note within their singing range with the same note name as the tone they heard at a higher register. In contrast, Tsimane’ participants produced notes that generally did not have an octave relationship to the stimulus.

"Our findings are consistent with the hypothesis that octave equivalence is culturally contingent", Jacoby summarizes.

These experiments provide new insights into the origins of different aspects of musical pitch perception by dissociating different parts of pitch perception that are tightly linked in Westerners, suggesting that pitch perception is more complex than previously thought.

This research is led by Nori Jacoby a Group Leader at the Max Planck Institute for Empirical Aesthetics and Josh McDermott, an associate professor at MIT. Other authors are Eduardo Undurraga and Tomas Ossandon, both assistant professors at the Pontifical Catholic University of Chile; Malinda McPherson, a graduate student in the Harvard/MIT Program in Speech and Hearing Bioscience and Technology; and Joaquin Valdes, a graduate student at the Pontifical Catholic University of Chile. The research was funded by the James S. McDonnell Foundation, the National Institutes of Health, and the Presidential Scholar in Society and Neuroscience Program at Columbia University.

Contact Publication:
Dr. Nori Jacoby

Original Publication:
Jacoby, N., Undurraga, E. A., McPherson, M. J., Valdés, J., Ossandón, T., & McDermott, J. H. (2019): Universal and Non-universal Features of Musical Pitch Perception Revealed by Singing. Current Biology. Online advance publication. doi:10.1016/j.cub.2019.08.020

See also MIT's news story