Positional Neutralization - Linguistics - University of California ...

difference in register is one of speech rate, which is to say, the vowels pronounced at the
faster rate have shorter durations. The reduction of [e, o] to [i, u], being duration-
dependent, applies pretonically only when those vowels are shortened sufficiently to
condition it. Posttonic vowels, on the other hand, are routinely short enough, unless
altered by phrase-final lengthening. Other processes are also sensitive to speech rate in
this way: in normal speech, nasalized mid vowels are never reduced, but in fast speech in
posttonic position only they are raised to merge with the high nasalized vowels. Major
attributes their failure to raise in normal speech to the fact that, as is typical
crosslinguistically, the nasalized vowels are phonetically longer than their oral
counterparts all things being equal, such that only a substantially faster speech rate would
contract them sufficiently to begin to challenge the articulation of their target heights.
While degree one reduction is irreversible and categorical, degree two reduction,
the raising of mid vowels clearly demonstrates gradient properties. The duration-
dependence of the process clearly indicates that it is not yet independent of phonetic
factors in the way that degree one reduction appears to be. Approaches treating both
reduction processes in Brazilian Portuguese as equivalently phonological have no means
of characterizing the failure of reduction in phrase-final vowels and the fast-speech
and sloppy” (Major 1985: 265). long. Pretonics in the same experiment were in all cases longer than these
posttonics, but shorter than the tonics.
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