Voice Onset Time Data Research Articles

Acoustic Analysis of Voicing Contrast in Malay Word-Initial Plosives Produced by Mandarin-Speaking Children

Voice Onset Time (VOT) is an acoustic measure widely used to measure the characteristics of plosives across various languages. This study investigates the acquisition of voicing contrast in Malay word-initial plosives produced by Mandarin-speaking children. Fifteen subjects between the ages of 3;00 to 7 and 11 were recruited. The children completed a picture-naming task, and the speech samples were audio-recorded and analyzed using PRAAT. Descriptive VOT values (ms) across ages were presented and compared to previous normative findings. Results revealed that children aged 3;00 produced only a short lag, while children aged 4;00 to 6;00 produced short lag-long lag contrast, which is not similar to the expected VOT pattern of Malay plosives. Additionally, with increasing age, children acquired adult-like VOT productions. The VOT distributions follow the developmental path proposed for languages with two-way contracts. This finding is the first VOT data on Malay word-initial plosives by Mandarin-speaking children. Maturity of motor development and coordination, as well as cross-linguistic exposure, influenced productions. Thus, further studies examining cross-linguistic influence, particularly controlling for the duration of exposure to L2 in multilingual language acquisition with a larger sample size, are warranted to validate the findings from this study.

A Bayesian Model for Prediction of Stroke with Voice Onset Time

The purpose of this study was to examine the changes in voice onset time (VOT) of stroke patients (elderly) and healthy elderly, and to compare them. Also, to propose a prediction model by considering speech analysis data. One hundred and fifty-three healthy elderly and fourty six stroke patients participated in this research study. Each group performed a plosive pronunciation of a Korean word 3 times, and voice signals were recorded. The speech analysis calculates probability parameters of speech signals. The parameters were mean, standard deviation, minimum value, and maximum value of the voice onset time. Finally, a Bayesian model was prepared with these parameters as inputs to predict stroke. Both groups’ speech signals were analyzed and confirmed that there were significantly different in their VOT parameters. And with the calculated probability of both stroke and healthy elderly, the Bayesian prediction model was proposed for stroke prediction. This present study shows that the proposed prediction model could assist in classifying whether the person having stroke or not through their voice onset time data.

Parallel adjustment of phonetic targets in L2 English voice onset time

The phonetic realization of any given speech sound varies considerably across speakers and languages. For instance, the voice onset time (VOT) of [kh] can range from ~40 ms to over 100 ms (Cho & Ladefoged, 1999). Within American English, recent research has demonstrated that the VOT of [kh] is also systematically and linearly related to the VOTs of [ph] and [th] (Chodroff & Wilson, 2017). In the present study, we investigated whether these relations were maintained across L2 speakers of English. L2 speech production could arise from independent acquisition (or adjustment) of the phonetic targets for each speech segment. Alternatively, the presence of covariation would indicate that properties of speech sounds may be altered in tandem. To investigate this, VOT data was obtained from a subset of the ALLSSTAR Corpus, which contained matched connected speech data from 26 L1 American English speakers and 114 L2 English speakers (22 unique L1s). Preliminary analysis revealed strong VOT covariation among aspirated stops across L2 speakers (rs = 0.67 to 0.74), and qualitatively equivalent covariation across L1 speakers (rs = 0.57 to 0.75). The observed covariation may arise from a universal principle of uniformity requiring near-identical implementation of the shared laryngeal feature value.The phonetic realization of any given speech sound varies considerably across speakers and languages. For instance, the voice onset time (VOT) of [kh] can range from ~40 ms to over 100 ms (Cho & Ladefoged, 1999). Within American English, recent research has demonstrated that the VOT of [kh] is also systematically and linearly related to the VOTs of [ph] and [th] (Chodroff & Wilson, 2017). In the present study, we investigated whether these relations were maintained across L2 speakers of English. L2 speech production could arise from independent acquisition (or adjustment) of the phonetic targets for each speech segment. Alternatively, the presence of covariation would indicate that properties of speech sounds may be altered in tandem. To investigate this, VOT data was obtained from a subset of the ALLSSTAR Corpus, which contained matched connected speech data from 26 L1 American English speakers and 114 L2 English speakers (22 unique L1s). Preliminary analysis revealed strong VOT covariation among aspirat...

Changes in voice onset time and motor speech skills in children following motor speech therapy: Evidence from /pa/ productions

This study evaluated changes in motor speech control and inter-gestural coordination for children with speech sound disorders (SSD) subsequent to Prompts for Restructuring Oral and Muscular Phonetic Targets (PROMPT) intervention. We measured the distribution patterns of voice onset time (VOT) for a voiceless stop (/p/) to examine the changes in inter-gestural coordination. Two standardized tests were used (Verbal Motor Production Assessment for Children (VMPAC), GFTA-2) to assess the changes in motor speech skills and articulation. Data showed positive changes in patterns of VOT with a lower pattern of variability. All children showed significantly higher scores for VMPAC, but only some children showed higher scores for GFTA-2. Results suggest that the proprioceptive feedback provided through PROMPT had a positive influence on speech motor control and inter-gestural coordination in voicing behavior. This set of VOT data for children with SSD adds to our understanding of the speech characteristics underlying speech motor control. Directions for future studies are discussed.

VOICE ONSET TIME OF INITIAL STOPS IN MANDARIN AND HAKKA: EFFECT OF GENDER

This paper examines the influence of gender upon voice onset time (VOT). VOT values of word-initial stops /p, t, k, p^h, t^h, k^h/ followed by three vowels /i, u, a/ in both Mandarin and Hakka revealed that male speakers produced longer VOTs in unaspirated stops than their female counterparts, but women produced longer VOTs in aspirated stops than male counterparts. In addition, VOT distinction in unaspirated and aspirated stops was greater in female speakers than in male speakers in both languages, perhaps because women tend to have a more careful manner of speech than men (Byrd 1992, 1994; Whiteside 1996). Gender has a statistically significant influence on VOTs in both Mandarin and Hakka. It is thus suggested that VOT data from different genders should be analyzed separately.

Voice onset time in Swedish children and adults

Voice onset time (VOT) is a temporal acoustic parameter, which reflects the timing of speech motor control. The objective of the work was to obtain normative VOT data in Swedish children. Thus, 150 children aged 8–11 years old and 36 adults were audio-recorded when producing the plosives in minimal pairs. Measures were made using waveforms and spectrograms. Results show that Swedish children developed adult-like VOT values between 9 and 10 years. By the age of 10 years prevoicing was also found to be completely adultlike in length. The results indicate that all Swedish adults do not produce voiced plosives with prevoicing. No evident gender differences were found. The obtained VOT values can be used as normative data when assessing children with speech and language disorders.

Hormones and temporal components of speech: sex differences and effects of menstrual cyclicity on speech

Voice onset time (VOT) is a salient acoustic parameter of speech which signals the ‘voiced’ and ‘voiceless’ status of plosives in English (e.g. the initial sound in ‘bat’ versus the initial sound in ‘pat’). As a micro-temporal acoustic parameter, VOT may be sensitive to changes in hormones which may affect the neuromuscular systems involved in speech production. This study adopted a novel approach by investigating the effects of menstrual cycle phase and sex on VOT. VOT data representing the six plosives of English (/p b t d k g/) were examined for seven women (age 20–23 years) at two phases of the menstrual cycle (day 18–25: high estrogen and progesterone; day 2–5: low estrogen and progesterone). Results indicated that menstrual cycle phase had a significant interaction with the identity of the plosive ( F (5,30) = 5.869, P < 0.002). Menstrual cycle phase also had significant effects on the contrasts between cognate voiced and voiceless plosives ( F (1,6) = 11.444, P < 0.02); samples from the high hormone phase displayed an enhanced voiced/voiceless contrast. Subsequently, VOT data samples from the two phases of the menstrual cycle were compared with those from five men in order to explore sex differences at different phases of the menstrual cycle. Low hormone phase samples displayed no significant sex differences for either VOT values ( F (1,10) = 2.085, P > 0.05), or the contrast between voiced and voiceless cognates ( F (1,10) = 0.407, P > 0.05). In contrast, the high hormone phase VOT samples displayed significant plosive by sex interactions ( F (5,50) = 4.442, P < 0.005). In addition, significant sex differences were found for the contrasts between cognate voiced and voiceless plosives ( F (1,10) = 5.019, P < 0.05); the women displayed a more marked voiced/voiceless contrast. The findings suggest that ovarian hormones play some role in shaping some temporal components of speech.

Developmental Trends in Voice Onset Time: Some Evidence for Sex Differences

This study reports on an investigation into the voice onset time (VOT) patterns of the plosives /p b t d/ in a group of 30 children aged 7 (n = 10), 9 (n = 10) and 11 (n = 10) years. Equal numbers of girls and boys participated in the study. Each child named a series of letter objects to elicit /p b t d/ in a syllable onset position with a fixed vowel context. VOT data were examined for age, sex and plosive differences with the following hypotheses: Firstly, that there would be sex differences in the VOT patterns of preadolescent children. Secondly, that the sex differences in VOT patterns would be linked to age and development, and that these would eventually become marked by the age of 11 years, by which time adult-like VOT values should have been achieved. Finally, that the extent of sex and age differences would be dependent upon the plosive being investigated. Results indicated patterns of decrease with age in the VOT values of /p b/ for the boys, with some evidence of increases in the VOT values of /t/ for the girls. In addition, ‘voiced’ and ‘voiceless’ cognates showed a more marked bimodal distribution in the girls‘ VOT patterns. This bimodal distribution was investigated by examining the degree of difference between the VOT values of voiced and voiceless cognate pairs /p b/ and /t d/, and examining the effects of age, sex and cognate pair. These results indicated that more marked sex differences in the ‘voiced’/‘voiceless’ contrast emerged between the data of the 9- and 11-year-olds, a pattern, which was more marked for the alveolar plosives. These preliminary results confirmed all three hypotheses. The findings are presented and discussed both within a developmental and sociophonetic framework.

Voice onset time in aphasia, apraxia of speech and dysarthria: a review

Voice onset time (VOT) is an objective temporal acoustic parameter defined as the time between the release of the oral constriction for plosive production and the onset of vocal fold vibrations. Many researchers consider VOT to be the most reliable acoustic cue for the distinction between voiced and voiceless stops. Previous studies have explored the physiological and linguistic factors underlying VOT production in normal speakers across several languages. A major clinical goal of acoustic analysis in speech disorder is to establish a correlation between the acoustic abnormalities and the phonetic perturbations. VOT could thus be used as an acoustic parameter that indicates the phonetic contrast between voiced and voiceless stops. This paper includes a critical review of the measurement of VOT, factors of VOT variability and the effect of neurogenic communication disorders on VOT. We review the VOT data from subjects who exhibit aphasia, apraxia of speech and dysarthria. These studies reveal that VOT perturbations in aphasia have been interpreted as phonemic or phonetic errors, while VOT abnormalities in apraxia of speech and dysarthria grossly reflect loss of motor control.

Voice onset time in normal-aged population.

Evidence suggests that the fine motor coordinations required to maintain the articulatory-laryngeal adjustments represented by measures of voice onset time (VOT) should change as a function of normal aging. This descriptive study obtained measures of VOT in healthy elderly subjects as a basis for extending the model of temporal speech control to the later years. Three groups of 10 subjects each were used. Group I was composed of subjects 25-39 years old. Groups 2 and 3 included subjects aged 65-74, and over 75, respectively. Subjects produced 30 tokens of three stimulus words, beat, pete, bead, following a carrier phrase. Wide-band spectrograms were prepared and measured, and the VOT data analyzed statistically. The following conclusions were drawn with respect to mean group age. The means of the VOTs did not differ significantly across subject groups. Standard deviations in the means did differ significantly, variability increased with age, both within subjects and between groups. The minimal separation of the phonemic boundaries for /b/ and /p/ decreased significantly as a function of aging, with the /p/ side of the distribution showing the greatest change.

Voice onset time, frication, and aspiration in word-initial consonant clusters.

The voice onset time (VOT) and the duration of the burst of frication noise at the release of a plosive consonant were measured from spectrograms of word-initial consonant clusters. Mean data from three speakers reading English words in a sentence frame indicated that the VOT changed as a function of the place of articulation of the plosive and as a function of the identity of the following vowel or sonorant consonant. Burst durations varied in a similar way such that the remaining interval of aspiration in /p, t, k/ was nearly the same duration in comparable phonetic environments. The VOT was longer before sonorants and high vowels than before mid- and low vowels. Aspiration was also seen in an /s/-sonorant cluster. To explain these regularities, production strategies and perceptual cues to a voicing decision for English plosives are considered. Variations in VOT are explained in terms of articulatory mechanisms, perceptual constraints, and phonological rules. Some VOT data obtained from a connected discourse were also analyzed and organized into a set of rules for predicting voice onset time in any sentence context.