The Roles of Tone and Syllable Structure in Mandarin Spoken Word Recognition
We used a gating paradigm to investigate the roles of tone, onset sonorancy, and nasal coda in Mandarin spoken word recognition. Our results showed that Mandarin Tone 1 (55) has an earlier Isolation Point (IP) than Tone 4 (51), which in turn has an earlier IP than Tone 2 (35) and Tone 3 (213), but the confidence ratings for Tone 1 are the lowest. We deduced that the high Tone 1 responses associated with low confidence ratings at early gates were due to an inherent Tone 1 bias. Based on the confusion analysis before the IP, a hierarchy of cues at the onset of tonal identification was also found: high > contour > low. High-onset tones, regardless of contours, were not misidentified as low-onset tones; but low-onset tones were sometimes misidentified as high-onset tones due to their contour shapes. Sonorant-initial syllables have an earlier IP than obstruent-initial syllables, but further analyses of covariance indicated that this is due to the fact that IP covariates with the duration of the initial consonant. Syllables without a nasal coda have an earlier IP than syllables with a nasal coda. This effect might be due to the interference of nasalization on tone perception or the delayed tonal contour realization due to the nasal coda (Xu 1998, Phonetica). A portion of these results can be found in Lai and Zhang (2007), and the entire results were presented at the 157th meeting of the Acoustical Society of America in 2009.