Positional Neutralization - Linguistics - University of California ...

In other words, the creak appears on the vowel by all accounts least likely to host
it, and fails to do so on its far more appropriate stressed counterpart. It is also not at all
clear in light of the foregoing how to explain the properties of the final vowel in (29),
[rnat] above, in which amplitude declines gradually to the end of the vowel, first with
creakiness, apparently easing into voicelessness at the end (with no evidence of an actual
glottal occlusion in the area).
Silverman (1997) recognizes these contradictions in the context of the appearance
of creakiness on low tones in Chong and Mandarin. As a solution, he proposes that the
creakiness occurring in the low tone environment actually has a different source and
mode of production than the creaky voice described articulatorily in most studies.
Specifically, he hypothesizes that low-tone creakiness is in fact a consequence of the
lowering of subglottal pressure (and hence airflow across the glottis) needed for the F0
drop, such that “the vocal folds may more readily seal the subglottal chamber, and thus
are only intermittently blown apart by eventual subglottal pressure increases. This slow
and irregular glottal pulse may give rise to creakiness” (1997: 151). He hypothesizes
further that this may be the case with phrase-final glottalization as well.
Silverman’s hypothesis is largely confirmed by the work of Slifka, reported in
Hanson, Stevens, Kuo, Chen and Slifka (2001). Slifka shows that in periods of phrase-
final “glottalization”, subglottal pressure is in fact gradually falling, while airflow is
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