Phonetic information is integrated across intervening nonlinguistic sounds.

Abstract

When the fricative noise of a fricative-vowel syllable is replaced by a noise from a different vocalic context, listeners experience delays in identifying both the fricative and the vowel (Whalen, 1984): mismatching the information in the fricative noise for vowel and consonant identity with the information in the vocalic segment appears to hamper processing. This effect was argued to be due to integration of the information relevant to phonetic categorization. The present study was intended to eliminate an alternative explanation based on acoustic discontinuities. Noises and vowels were again cross-spliced, but, in addition, the first 60 msec of the vocalic segment (which comprised the consonant-vowel transitions) either had a nonlinguistic noise added to it or was replaced by that noise. The fricative noise and the majority of the vocalic segment were left intact, and both were quite identifiable. Mismatched consonant information caused delays both for original stimuli and for ones with the noise added to the transitions. Mismatched vowel information caused delays for all stimuli, both originals and ones with the noise. Additionally, syllables with a portion replaced by noise took longer to identify than those that had the noise added to them. When asked explicitly to tell the added versions from the replaced, subjects were unable to do so. The results indicate that listeners integrate all relevant information, even across a nonlinguistic noise. Completely replacing the signal delayed identifications more than did adding the noise to the original signal. This was true despite the fact that the subjects were not aware of any difference.