Positional Neutralization - Linguistics - University of California ...

generalization to be made for UVR systems. The two types are named contrast-enhancing
and prominence-reducing UVR.
Contrast-enhancing vowel reduction is a neutralization process whereby
“undesirable or perceptually challenging vowel contrasts are limited to stressed position”
(Crosswhite 2001: 22). In this way it is a direct descendent of Steriade’s Licensing-by-
Cue approach to Positional Neutralization. The idea is that contrasts are deployed by
speakers only in positions in which the phonetic cues which make those contrasts
perceptually robust are present and strong. For vowel-quality contrasts, Steriade (1994)
identifies duration as the phonetic cue most indispensable for accurate perception. In
positions of lesser duration, then, only the most easily perceptible vowel contrasts will be
licensed, while in, e.g., stressed syllables, which are in many languages associated with
additional duration, the entire inventory of contrasts may be realized. Crosswhite follows
Steriade in this, presenting arguments showing why specifically mid vowels are targeted
by so many reduction systems, and why the resulting systems of unstressed vocalism are
so often /i,u,a/. The arguments are familiar from the phonetic literature on crosslinguistic
regularities in the shape of vowel inventories: she cites specifically optimal dispersion in
the vowel space (Liljencrants and Lindblom 1972, Flemming 1995), the quantal stability
of the corner vowels, meaning the tendency to keep stable acoustic realizations even with
a degree of articulatory variation (Stevens 1986), and the tendency for certain pairs of
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