Automatic voice disorder recognition using acoustic amplitude modulation features

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2004.Includes bibliographical references (p. 114-117).An automatic dysphonia recognition system is designed that exploits amplitude modulations (AM) in voice using biologically-inspired models. This system recognizes general dysphonia and four subclasses: hyperfunction, A-P squeezing, paralysis, and vocal fold lesions. The models developed represent processing in the auditory system at the level of the cochlea, auditory nerve, and inferior colliculus. Recognition experiments using dysphonic sentence data obtained from the Kay Elemetrics Disordered Voice Database suggest that our system provides complementary information to state-of-the-art mel-cepstral features. A model for analyzing AM in dysphonic speech is also developed from a traditional communications engineering perspective. Through a case study of seven disordered voices, we show that different AM patterns occur in different frequency bands. This perspective challenges current dysphonia analysis methods that analyze AM in the time-domain signal.by Nicolas Malyska.S.M

Prosodically Conditioned Realization of Voiced Stops and Vowels in Yucatecan Spanish

This dissertation investigates the acoustic nature and distribution of prosodic strengthening in relation to the Prosodic Word domain and prosodic prominence in Yucatecan Spanish. In order to do so, phonologically voiced stops and word-initial vowels were examined in a corpus of sociolinguistic interviews and a read speech task with 16–21 speakers of the variety. The results provide evidence for prosodic strengthening of both voiced stops and word-initial vowels. The acoustic manifestations of prosodic strengthening of voiced stops are (i) longer duration, (ii) greater change in intensity, and, in extreme cases of strengthening, (iii) presence of a release burst. Strengthening of word-initial vowels is manifested through glottalization, which is present in the first portion of the vowel. Prosodic strengthening occurs in PW-initial position and especially under lexical stress, although accentuation may also play a role. Thus, prosodic strengthening is used to indicate (post)lexical prominence and boundaries at the PW level. In terms of speaker-specific variation, Yucatec Maya language dominance does not appear to favor more strengthened realizations either of voiced stops or word-initial vowels, while gender has no effect on the distribution of strengthened realizations. Finally, a proposal is made for the strengthening of voiced stops and glottalization of word-initial vowels being used to mark the left edges of a recursive PW in Yucatecan Spanish

Effects of tone on the three-way laryngeal distinction in Korean: An acoustic and aerodynamic comparison of the Seoul and South Kyungsang dialects

This is the publisher's version, made available with the permission of the publisher.The three-way laryngeal distinction among voiceless Korean stops has been well documented for the Seoul dialect. The present study compares the acoustic and aerodynamic properties of this stop series between two dialects, non-tonal Seoul and tonal South Kyungsang Korean. Sixteen male Korean speakers (eight from Seoul and eight from Kyungsang) participated. Measures collected included VOT, f0 at vowel onset, H1-H2, and air pressure and airflow. The presence versus absence of lexical pitch accent affects both the acoustic and aerodynamic properties. First, Seoul speakers use a combination of f0 and VOT to distinguish the three-way contrast of Korean stops, while Kyungsang speakers mainly use VOT. Second, the presence of lexical pitch for Kyungsang speakers makes f0 an unreliable acoustic cue for the three Korean stops. Third, dialectal differences in VOT to mark the three-way distinction support the notion of a diachronic transition whereby VOT differences between the lenis and aspirated stops in Seoul Korean have been decreasing over the past 50 years. Finally, the aerodynamic results make it possible to postulate the articulatory state of the glottis, indicating a positive correlation with acoustic parameters. Based on the acoustic and aerodynamic results, phonological representations of Korean stops for the tonal and non-tonal dialects are suggested

Vocal fold vibratory patterns in tense versus lax phonation contrasts

This study explores the vocal fold contact patterns of one type of phonation contrast--the tense vs lax phonation contrasts of three Yi (Loloish) languages. These contrasts are interesting because neither phonation category is very different from modal voice, and because both phonations are largely independent of the languages' tonal contrasts. Electroglottographic (EGG) recordings were made in the field, and traditional EGG measures were derived. These showed many small but significant differences between the phonations, with tense phonation having greater contact quotients and briefer but slower changes in contact. Functional data analysis was then applied to entire EGG pulse shapes. The resulting first principal component was found to be mostly strongly related to the phonation contrasts, and correlated with almost all the traditional EGG measures. Unlike the traditional measures, however, this component also seems to capture differences in abruptness of contact. Furthermore, previously collected perceptual responses from native speakers of one of the languages correlated better with this component than with any other EGG measure or any acoustic measure. The differences between these tense and lax phonations are not large, but apparently they are consistent enough, and perceptually robust enough, to support this linguistic contrast

AFLA 21: The Proceedings of the 21st Meeting of the Austronesian Formal Linguistics Association

The 21st annual meeting of the Austronesian Formal Linguistics Association (AFLA 21) was held on 23-25 May, 2014 at the University of Hawai‘i at Mānoa. The program consisted of 28 presentations, including three plenary talks by Diane Massam, Yuko Otsuka, and Kie Zuraw. This volume includes 17 papers presented at the conference