Positional Neutralization - Linguistics - University of California ...

latter case the same feature is implemented in such a way or to such a degree that it can
no longer be considered an automatic consequence of something else in the speech signal.
Rather, it must be realized intentionally, a planned characteristic of the target articulation.
At this point it is necessary to underscore a significant difference in the operation
of the phonologization process as it is conceived here in the window model. In all
previous discussions of the realization of vowel height, with the exception of schwa,
unreduced, gradiently reduced and categorically reduced vowels have all had some target
window specified for the realization of their height features. As proposed by Keating
(1996), the narrowing or widening of target windows allows us to model various degrees
of phonetic underspecification, rather than conceiving of it as the all or nothing presence
or absence of a specified target for a given dimension of a segment’s phonetic realization.
The discussion of vowels herein has thus availed itself of this capacity, assuming in all
cases that vowels, save a putatively-targetless schwa, bear some spectral target
specification or another, whether it be one with a wide window, indicating greater
variation in response to the pressures of duration, or a narrower one, indicating relative
stability despite such pressures. In discussion of the transition from passive (contingent)
devoicing to active (planned) devoicing, the point of phonologization will certainly entail
the addition of a target (i.e. a glottal abduction gesture) where none was previously
found. This is not, however, to suggest that the gradient devoicing in the pre-
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