Positional Neutralization - Linguistics - University of California ...

The preceding sections have shown that the only clearly attested patterns of
neutralization involving stressed and unstressed syllables are those affecting primarily
height, nasalization, or quantity. For each of these features, duration is either a well-
known cue for the contrast in question, or in the case of quantity, potentially the only cue
for the contrast in question. Patterns of UVR conspicuously not attested include those
based on contrasts of palatality, roundness, and ATR, all commonly active in harmony
systems (see chapter 4), though not known to be strongly cued by duration. The following
section explores the phonetic basis of UVR in more detail.
2.2. The Phonetics of Vowel Reduction
The fact that unstressed vowel reduction should so definitively prefer targeting
height contrasts is perfectly comprehensible in light of the phonetic environment in which
it generally arises. The correlation between the presence of UVR in a language and
duration as a primary correlate of lexical stress has been widely recognized for decades
(see, e.g. Lehiste 1970). Generally speaking, UVR appears in languages with a large
durational asymmetry between stressed and unstressed syllables, such that unstressed
syllables undergo significant durational contraction relative to a substantially longer
stressed syllable, particularly under increased rate of speech.
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