Individual differences in use of English fricative perceptual cues.

Abstract

This study examines individual variation as a potential explanation for contradictory and inconsistent reports of English speakers’ use of acoustic cues in identification of the voiceless sibilants [s] and [∫]. While there is widespread agreement that the spectral shape of turbulent noise is key for identification of these two categories, some studies find that formant transitions to and from the noise also influence identification [Whalen, J. Acoust. Soc. Am. 69, 275–282 (1981)], while others do not [Harris, Lang. Speech 1, 1–7 (1958)]. Similarly, the majority of studies investigating the effect of vowel context on fricative perception show that the presence of round vowels biases listeners toward perception of [s] [Kunisaki and Fujisaki, Ann. Bull. RILP 11, 85–91 (1977)], but others show precisely the opposite effect, where round vowels favor [∫] responses [Nittrouer and Studdert‐Kennedy, J. Speech Hear. Res. 30, 319–329 (1987)]. In this study, 30 native English speakers participated in a labeling experiment that fully crossed all three factors—spectral noise shape, formant transitions, and vocalic context—for each subject. Every pattern of cue use found in the literature is also found in one or more of the individuals, which may explain why averaged results vary so widely across reports.