Measures of Speech Rhythm in East-Asian Tonal Languages

The most frequently used variables for language rhythm categorisation have been measured for some tonal languages. Cantonese, Mandarin, Thai and Vietnamese are languages which ground their prosodic properties on phonological tones and are supposed to reserve secondary role to stress whose functions are controversially bounded to prominence patterns of constituency. Therefore, a distinctive characterisation in terms of speech rhythm is not usually acknowledged for them. In spite of these phonological expectancies, our results reflect a clear-cut distribution of these languages along timing categories corresponding to languages traditionally considered as stresstimed or syllable-timed (e.g. English vs. Spanish). The differences shown by the speech samples we analysed seem to be due to phenomena related to specific syllable compression patterns and vowel reduction / lengthening strategies affected by tone and more general prosodic rules.