The phonological representation of [voice] in speech perception

This paper examines to what extent phonological representations affect word identification. The contrast under investigation involves the interaction between voicing and vowel length in Dutch. Dutch has underlying contrasts both in obstruent voicing and in vowel length. The voicing contrast is neutralized on the surface in syllable-final position. Also, both long and short vowels are lengthened by some 25 msec when followed by medial voiced obstruents. The present study investigated whether this vowel length cue influenced listeners when hearing stimuli with ambiguous vowel duration in an identical, neutralized consonantal context in which the underlying representation of the obstruent following the vowel differed in voicing. A vowel length continuum ([at] to [a:t]) was created and appended to initial consonants to make two pairs of real words. Each pair differed in vowel length with opposite underlying final consonant representations: /zat/-/za:d/, and /stad/-/sta:t/. Our question was whether the vowel category boundaries would be different in pairs like /zat/-/za:d/ as compared to /stad/-/sta:t/. Although the underlying consonant is either voiced or voiceless, the surface word-final consonant for both pairs of stimuli is always voiceless ([t]). If the listener uses a surface representation with a voiceless consonant to recognize the words, there should be no difference in categorization of the vowel-length continua. The results of a vowel categorization task, however, showed a significant difference in the location of the phoneme boundaries between the two continua, suggesting that listeners' perception seems to be guided by the underlying phonological representation of words.