Shorter Voice Onset Time Values Research Articles

The Effect of Tonal Changes on Voice Onset Time in Mandarin Esophageal Speech

The present study investigated the effect of tonal changes on voice onset time (VOT) between normal laryngeal (NL) and superior esophageal (SE) speakers of Mandarin Chinese. VOT values were measured from the syllables /pha/, /tha/, and /kha/ produced at four tone levels by eight NL and seven SE speakers who were native speakers of Mandarin. Results indicated that Mandarin tones were associated with significantly different VOT values for NL speakers, in which high-falling tone was associated with significantly shorter VOT values than mid-rising tone and falling-rising tone. Regarding speaker group, SE speakers showed significantly shorter VOT values than NL speakers across all tone levels. This may be related to their use of pharyngoesophageal (PE) segment as another sound source. SE speakers appear to take a shorter time to start PE segment vibration compared to NL speakers using the vocal folds for vibration.

Place of articulation and first formant transition pattern both affect perception of voicing in English

Voice onset time (VOT) and first-formant (F1) transition characteristics are both important phonetic cues for voicing categorization of pretonic stops in English. These cues also covary with place of articulation in production, such that bilabials are produced with shorter VOT values, and velars are produced with longer VOT values. This study investigated the effects of place of articulation and F1transition pattern on voicing categorization of VOT continua. Listeners categorized for voicing and place of articulation the stop consonant in VCV and CV stimuli for which the variables F1transition pattern, place of articulation (bilabial, alveolar, and velar), and VOT were fully crossed. A logistic regression analysis shows that bilabial and alveolar stimuli were more likely than velar stimuli to be classified as voiceless, largely independent of F1transition pattern. Increasing F1onset frequency and shortening transition duration also made voiceless judgments more likely. The magnitude of theF1 transition effects was considerably larger than the place of articulation effect. The results are inconsistent with models of consonant classification in which acoustic–phonetic cues for place of articulation are not involved in the perception of the voicing contrast. However, the observed perceptual interaction between place of articulation and voicing may be consistent with either a feature- or segment-based model of consonant classification.

LEXICAL FACTORS AND SEGMENTAL ACCURACY IN SECOND LANGUAGE SPEECH PRODUCTION

Voice onset time (VOT) was measured in the production of /t/ in the initial position of 60 English words spoken by native English (NE) speakers and native Spanish (NS) speakers who began learning English before or after the age of 21 years. The subjects rated the words for familiarity, age of acquisition, imageability, and relatedness to word(s) in the Spanish lexicon. The subjects in all three groups showed two well-known phonetic effects: They produced longer VOT values in the context of high than nonhigh vowels, and longer VOT in one- than in two-syllable words. As expected, the NS subjects who learned English prior to the age of 21 years judged the English words to be more familiar and more like a Spanish word than did the subjects who began learning English later in life. Also, many but not all of the NS subjects produced /t/ with shorter VOT values than did the NE subjects. However, regression analyses showed that none of the lexical factors mentioned above or the text frequency of the 60 English words examined affected the NS subjects' VOT values. Thus, variation in the accuracy with which NS subjects produce English /t/ must be accounted for by factors other than the lexical status of the words in which /t/ occurs.

Differences in Susceptibility to the “Blending Illusion” Among Native Hebrew and English Speakers

This study was designed to explore whether native Hebrew and English speakers differ in their susceptibility to the blend illusion and in their lip-reading of words and cliché sentences. Four lip-reading tests, designed to assess recognition of syllables, words, and overlearned sentences, were administered to two groups of subjects who were matched for age, sex, and educational level. The English-speaking group showed significantly higher susceptibility to the blending illusion. The source of the effect was in the enhanced sensitivity to the auditory input in males along with reduced number of auditory biases in females. No sex differences in lip-reading of any item of the lip-reading battery was obtained in native Hebrew speakers. Subjects in both groups performed at the same level in recognizing the words and overlearned sentences. The result is attributed to the shorter Voice Onset Time values of Hebrew when native listeners would hear acoustic messages prior to discernable lip movements.

Age of learning affects the authenticity of voice-onset time (VOT) in stop consonants produced in a second language

This study examined whether Spanish-English bilinguals are able to fully differentiate Spanish and English /t/ according to voice-onset time (VOT) if they learn English as a second language (L2) in early childhood. In experiment 1, VOT was measured in Spanish words spoken by Spanish monolinguals, in English words spoken by English monolinguals, and in Spanish and English words spoken by bilinguals who learned English either as young children or as adults. As expected, the Spanish monolinguals produced /t/ with considerably shorter VOT values than the English monolinguals. Also as expected, the late L2 learners produced English /t/ with "compromise" VOT values that were intermediate to the short-lag values observed for Spanish monolinguals and the long-lag values observed for English monolinguals. The early learners' VOT values for English /t/, on the other hand, did not differ from English monolinguals' VOT. The same pattern of results was obtained for stops in utterance-medial position and in absolute utterance-initial position. The results of experiment 1 were replicated in experiment 2, where bilingual subjects were required to produce Spanish and English utterances (sentences, phrases, words) in alteration. The results are interpreted to mean that individuals who learn an L2 in early childhood, but not those who learn an L2 later in life, are able to establish phonetic categories for sounds in the L2 that differ acoustically from corresponding sounds in the native language. It is hypothesized that the late L2 learners produced /t/ with slightly longer VOT values in English than Spanish by applying different realization rules to a single phonetic category.

Cross-language switching in stop consonant perception and production by Dutch speakers of english

Voiceless /p,t,k/ are implemented as aspirated stops in English, but as unaspirated stops in Dutch. We examined identification of a voice onset time (VOT) continuum ranging from /da/ to /ta/ in two language “sets” designed to induce native Dutch subjects to perceive the stimuli as if they were listening to Dutch or English. The effect of language set was highly significant, but the boundary shift was very small (2.1 ms longer in English than in Dutch) for three groups of subjects differing widely in English language proficiency. It nevertheless showed the subjects were aware of acoustic differences distinguishing Dutch and English /t/ and that the procedures were effective in creating differing language sets. Nearly every subject produced a longer mean VOT in English than Dutch /t/. The magnitude of the production shift was significantly greater for proficient than non-proficient subjects. Proficient Dutch speakers of English produced Dutch /t/ with shorter VOT values than non-proficient subjects, suggesting they formed a new category for English /t/. We speculate that the language set effect was small because subjects used their English /t/ category to identify stops in both sets. This was probably due to the fact that the synthetic stimuli, which were modeled on the English /t/-/d/ contrast, differed substantially from their Dutch /t/ category.

Speech perception and language acquisition

Voice onset time (VOT) and first-formant (F1) transition characteristics are both important phonetic cues for voicing categorization of pretonic stops in English. These cues also covary with place of articulation in production, such that bilabials are produced with shorter VOT values, and velars are produced with longer VOT values. This study investigated the effects of place of articulation and F1transition pattern on voicing categorization of VOT continua. Listeners categorized for voicing and place of articulation the stop consonant in VCV and CV stimuli for which the variables F1transition pattern, place of articulation (bilabial, alveolar, and velar), and VOT were fully crossed. A logistic regression analysis shows that bilabial and alveolar stimuli were more likely than velar stimuli to be classified as voiceless, largely independent of F1transition pattern. Increasing F1onset frequency and shortening transition duration also made voiceless judgments more likely. The magnitude of theF1 transition effects was considerably larger than the place of articulation effect. The results are inconsistent with models of consonant classification in which acoustic–phonetic cues for place of articulation are not involved in the perception of the voicing contrast. However, the observed perceptual interaction between place of articulation and voicing may be consistent with either a feature- or segment-based model of consonant classification.

Phonological performance in gerontological speech.

The older speaker's production of phonology is affected by physiological and anatomic changes that occur with age. The differences in phonatory performance between a group of 20 young adults (aged 21 to 32) and 20 older adults (aged 68 to 82) were measured in the articulatory rate dimension. Spectrographic measurement revealed that older adults produced significantly longer vowels, longer silent intervals of stop consonants, and shorter voice onset time values than young adult speakers.

An Instrumental Analysis of the Voicing Contrast in Word-Initial Stops in the Speech of Four-Year-Old English-Speaking Children

This paper reports on an investigation of the voice-onset-time (VOT) characteristics of word-initial stops produced by four four-year-old children. Instrumental analysis of the children's spontaneous speech showed that they had distinct distributions for voiced and voiceless stops at all three places of articulation and that there was very little overlap between voiced and voiceless cognates. Comparison of words uttered in isolation with words uttered in a sentence context revealed that these children had shorter VOT values in running speech. Reanalysis of data from younger children showed evidence of such modification according to context at age 1;9. However, even at age 4 the data were not completely adult-like: Compared with adults, the four-year-olds had longer mean VOT values, there was a greater range of values and there was less modification according to sentence context. The four-year-olds' data were interpreted as further evidence for the position that in producing voiceless stops in terms of mean VOT values, children first overshoot adult values and then only gradually draw them back towards adult values.