The Time Course of Breathiness and Laryngealizationn in Vowels
In a language where breathiness or laryngealization is a contrastive property of vowels, such non-modal phonation lasts longer and may be of greater magnitude than in a language where it is an accident of consonant context. In Tagalog, breathy phonation occurs incidentally on vowels after /h/, and laryngealized phonation occurs after glottal stops. Mazatec, on the other hand, employs breathy and laryngealized vowels as separate phonemes that contrast with modal vowels. Several acoustic measures show that the difference between nonrnodal and modal vowels is stronger and lasts longer in Mazatec than in Tagalog. Contrary to expectations, cross-speaker variation is not greater in Tagalog.
The main experiment examined words from 6 male and 6 female speakers of each language. A second experiment used 4 male and 4 female speakers of Chong, 1 male speaker of Mpi, and 1 male and 10 female speakers of Navajo. Three breathy, 3 laryngealized, and 3 modal vowels from each speaker were analyzed. To determine the time course of phonation effects, measurements were made at 25 ms intervals through each vowel. The measurements were H1-H2 (hypothesized to reflect the open quotient of the glottal vibration), H1-F2 (an approximation of spectral slope, hypothesized to reflect the abruptness of vocal fold closure ), and cepstral peak prominence (a measure of periodicity).