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C A Fowler

Publications and source records attributed to C A Fowler.

46 records · Page 3Linked to original sources
PubMed1983

Converging sources of evidence on spoken and perceived rhythms of speech: cyclic production of vowels in monosyllabic stress feet.

The article reviews the literature from psychology, phonetics, and phonology bearing on production and perception of syllable timing in speech. A review of the psychological and phonetics literature suggests that production of vowels and consonants are interleaved in syllable sequences in such a way that vowel production is continuous or nearly so. Based on that literature, a hypothesis is developed concerning the perception of syllable timing assuming that vowel production is continuous. The hypothesis is that perceived syllable timing corresponds to the times sequencing of the vowels as produced and not to the timing either of vowel onsets as conventionally measured or of syllable-initial consonants. Three experiments support the hypothesis. One shows that information present during the portion of an acoustic signal in which a syllable-initial consonant predominates is used by listeners to identify the vowel. Compatibly, this information for the vowel contributes to the vowel's perceived duration. Finally, a measure of the perceived timing of a syllable correlates significantly with the time required to identify syllable-medial vowels but not with time to identify the syllable-initial consonants. Further support for the proposed mode of vowel-consonant production and perception is derived from the literature on phonology. Language-specific phonological conventions can be identified that may reflect exaggerations and conventionalizations of the articulatory tendency for vowels to be produced continuously in speech.

Humans↗
PubMed1981

Production and perception of coarticulation among stressed and unstressed vowels.

A pair of experiments examines first the coarticulatory relations among certain stressed and unstressed vowels, and next the perception of coarticulated unstressed vowels. The first study finds the acoustic properties of unstressed medial and, to a substantially lesser extent, of stressed medial, to be assimilated to the properties of their flanking vocalic contexts. Both initial and final flanking vowels coarticulate with medial, but carryover coarticulatory effects tend to exceed anticipatory effects. In a secondary experiment, listeners' manners of perceiving the coarticulated unstressed vowels of the first experiment are shown to be coupled to, or to be compatible with, the talkers' coarticulatory strategies. In particular, perceivers hear acoustically identical vowels to be different when the vowels appear in different contexts of flanking vowels. Similarly, instances of that are acoustically different due to different coarticulatory influences on them sound the same to listeners as long as each appears in its appropriate context of flanking vowels.

Humans↗
PubMed1981

Immediate compensation in bite-block speech.

An experiment was conducted to examine whether a bite block affects the latency and/or the quality of spoken vowels. The results suggest that vowels spoken with the bite block and vowels spoken normally were (1) of the same latency, that is, the same time elapsed between visual presentation and initiation of response; and (2) of the same quality, and that is, the acoustic measures of the vowels did not differ substantially. Moreover, there was minimal evidence of improvement in either latency or quality with practice, and minimal evidence of an effect of time pressure on the quality of bite-block vowels. A detailed consideration is given to the implications of these and other findings for two recent perspectives on vowel production.

Humans↗
PubMed1981

A relationship between coarticulation and compensatory shortening.

A comparison of the literatures on coarticulatory influences of a stressed vowel on consonants and unstressed vowels and on 'compensatory shortening' of stressed vowels in the contexts of consonants and unstressed vowels suggests that the two timing effects may be related. An experiment was conducted to provide an explicit comparison and to test a hypothesis that compensatory shortening and coarticulation are not separate timing phenomenona. The two timing effects were found to pattern very similarly and both to be predicted by Lindblom and Rapp's compensatory shortening formula. 5 of 6 subjects showed significant correlations between coarticulation and shortening.

Humans↗
PubMedDate not supplied

Coordination and coarticulation in speech production.

In this article, we consider the concepts of coordination and coarticulation in speech production in the context of a task-dynamic model. Coordination reflects the transient establishment of constrained relationships among articulators that jointly produce linguistically significant actions of the vocal tract--that is phonetic gestures--in a flexible, context-sensitive manner. We ascribe the need for these constraints in part to the requirement of coarticulatory overlap in speech production. Coarticulation reflects temporally staggered activation of coordinative constraints for different phonetic gestures. We suggest that the anticipatory coarticulatory field for a gesture is more limited than look-ahead models have suggested, consistent with the idea that anticipatory coarticulation is the onset of activation of coordinative constraints for a forthcoming gesture. Finally, we ascribe much of the context-sensitivity in the anticipatory or carryover fields of a gesture (variation due to "coarticulation resistance") to low-level (below the speech plan) interactions among the coordinative constraints for temporally overlapping gestures.

Female↗