The role of vowel transitions in the perception of Mandarin sibilants

Vocalic formant transitions have been reported to play a role in identification of sibilants in English (e.g., Whalen, 1981), Shona (Bladon et al., 1987), and other languages. In distinguishing the Mandarin /s/-/ʂ/ contrast, while F2 at vowel onset is suggested to reflect the vocal tract configuration at the moment of fricative release into the vowel (Stevens et al., 2004), it has never been studied whether this acoustic cue contributes to phoneme perception. This study used a F2 continuum spliced between a fricative highly confusable between /s/ and /ʂ/ and the vowel /a/ for an identification task on 16 native listeners. The results did not show a categorical perception effect on /sa/ and /ʂa/ distinction along the F2 continuum. The second experiment used the naturally produced /sa/ and /ʂa/ whose vocalic transitions were cross-spliced to investigate if the listeners were affected by misleading formant transitions. Listeners' goodness ratings revealed no sensitivity to the acoustic manipulation. It was concluded that F2 is not a primary cue for the place distinction of Mandarin /s/ and /ʂ/. Our findings support Wagner et al.'s (2006) observation that the contribution of formant transitions to fricative perception is language-specific and depends on spectral similarity among target fricatives.