Vocal imitations of basic auditory features.

Describing complex sounds with words is a difficult task. In fact, previous studies have shown that vocal imitations of sounds are more effective than verbal descriptions [Lemaitre and Rocchesso (2014). J. Acoust. Soc. Am. 135, 862-873]. The current study investigated how vocal imitations of sounds enable their recognition by studying how two expert and two lay participants reproduced four basic auditory features: pitch, tempo, sharpness, and onset. It used 4 sets of 16 referent sounds (modulated narrowband noises and pure tones), based on 1 feature or crossing 2 of the 4 features. Dissimilarity rating experiments and multidimensional scaling analyses confirmed that listeners could accurately perceive the four features composing the four sets of referent sounds. The four participants recorded vocal imitations of the four sets of sounds. Analyses identified three strategies: (1) Vocal imitations of pitch and tempo reproduced faithfully the absolute value of the feature; (2) Vocal imitations of sharpness transposed the feature into the participants' registers; (3) Vocal imitations of onsets categorized the continuum of onset values into two discrete morphological profiles. Overall, these results highlight that vocal imitations do not simply mimic the referent sounds, but seek to emphasize the characteristic features of the referent sounds within the constraints of human vocal production.