Holger Hennig, Ragnar Fleischmann, Anneke Fredebohm, York Hagmayer, Jan Nagler, Annette Witt, Fabian J Theis, and Theo Geisel (2011)

The nature and perception of fluctuations in human musical rhythms

PLoS ONE, 6(10):ee26457-ee26457.

Examined the correlation properties of temporal fluctuations in music on the timescale of rhythms and their influence on the perception of musical performances. The authors were able to established long-range fluctuations as an inevitable natural companion of both simple and complex human rhythmic performances. To test the preference of computer generated music that has been ``humanized'' compared to plain computer generated music, 39 choir singers (mean age 26 years) were asked to first rate their music expertise on a scale of 1 (amateur) to 6 (professional), yielding an average of 3.8. Then the listeners heard 2 versions (listening to each version 3 times) of a computer generated song that was either humanized, using professional audio editing software which offers a humanizing feature that artificially generates rhythmic fluctuations, or was accompanied by white noise. The results demonstrated that listeners strongly preferred long-range correlated (LRC) fluctuations in musical rhythms. The authors therefore conclude that the favorable fluctuation type for humanizing interbeat intervals coincides with the one generically inherent in human musical performances.