Department of Linguistics

The purpose of this paper is to provide a comprehensive understanding of how contrastive phonation is produced and perceived by native speakers of a language with both tonal and phonation contrasts, Yi. In the production experiment, we measure a wide scope of relevant physiological and acoustic parameters, which show substantial physiological-acoustic coupling: a Contact Quotient (CQ) distinction is the essential property of the phonation contrast, while H1*-H2* and H1*-A1*, which are significantly correlated with CQ, are the best acoustic measures for the phonation contrast. The bandwidth of the first formant (B1) and the Cepstral peak prominence (CPP) are effective acoustic cues too. In addition to the well-established contributions of the vocal folds, this study gives insight into the role of supraglottal settings for the phonation contrast. A consistent F1 difference for the phonation contrast in Yi indicates a shape change in the vocal tract, supporting the multidimensional phonation model proposed by Edmondson & Esling (2006). Such a supraglottal effect is similar to that in ATR (Advanced Tongue Root) languages, related to a change in pharyngeal size, though in Yi the direction is RTR (Retracted Tongue Root). With more detailed discussion about variations in the tense vs. lax contrast across speakers as well as across languages, the relativity of phonation contrasts is highlighted. The perception experiment looks at the effectiveness of voice quality, F0 and F1 for the perception of phonation categories by Yi listeners. We draw a perception map from a perceptual confusion matrix and then compare that with a production map. It is found that listeners heavily rely on F1 for the perception of the tense vs. lax contrast, though it is a secondary cue in production. However, the perception map generally agrees with the production map, though the perception map varies across listeners. The variation found in the production experiment suggests a possible sound change in the phonation contrast. The variation in the perception map further indicates the future direction of the sound change: Vowel quality might eventually take over as the distinctive feature of the tense vs. lax contrast.