Effects of consonantal constrictions on voice quality

A speech production experiment with electroglottography investigated how voicing is affected by consonants of differing degrees of constriction. Measures of glottal contact [closed quotient (CQ)] and strength of voicing [strength of excitation (SoE)] were used in conditional inference tree analyses. Broadly, the results show that as the degree of constriction increases, both CQ and SoE values decrease, indicating breathier and weaker voicing. Similar changes in voicing quality are observed throughout the course of the production of a given segment. Implications of these results for a greater understanding of source-tract interactions and for the phonological notion of sonority are discussed

A high-speed laryngoscopic investigation of aryepiglottic trilling

Six aryepiglottic trills with varied laryngeal parameters were recorded using high-speed laryngoscopy to investigate the nature of the oscillatory behavior of the upper margin of the epilaryngeal tube. Image analysis techniques were applied to extract data about the patterns of aryepiglottic fold oscillation, with a focus on the oscillatory frequencies of the folds. The acoustic impact of aryepiglottic trilling is also considered, along with possible interactions between the aryepiglottic vibration and vocal fold vibration during the voiced trill. Overall, aryepiglottic trilling is deemed to be correctly labeled as a trill in phonetic terms, while also acting as a means to alter the quality of voicing to be auditorily harsh. In terms of its characterization, aryepiglottic vibration is considerably irregular, but it shows indications of contributing quasi-harmonic excitation of the vocal tract, particularly noticeable under conditions of glottal voicelessness. Aryepiglottic vibrations appear to be largely independent of glottal vibration in terms of oscillatory frequency but can be increased in frequency by increasing overall laryngeal constriction. There is evidence that aryepiglottic vibration induces an alternating vocal fold vibration pattern. It is concluded that aryepiglottic trilling, like ventricular phonation, should be regarded as a complex, if highly irregular, sound source

Properties of the Anterior and Posterior Click Closures in N|uu

In this dissertation, the phonetic and phonological system of N|uu is described and analyzed. The dissertation is based on original fieldwork by the author. As is shown at the outset in Chapter 2, N|uu is a Tuu (formerly 'Southern Khoisan') language of the Kalahari region of South Africa. It is a severely endangered language on the verge of extinction, spoken at the time of writing by less than ten elderly speakers. At the same time, it is a phonetically and phonologically highly complex language, most notably including a large number of phonologically contrastive click consonants. In Chapter 3, an overview of the entire phoneme inventory is presented for the first time, including not only the click subsystem (here, the terms simultaneous release vs. sequential release are introduced), but also the non-click consonants and vowels, as well as the as yet unanalyzed lexical tone system. Then, in Chapter 4, the phonological structure of N|uu is analyzed qualitatively and quantitatively, and the foot is for the first time identified as a fundamental organizing unit in the prosodic system of the language. Also, the complexity of phonological words in N|uu is shown to be considerably greater than previously thought. Chapter 5 presents two detailed experimental case studies (one on the anterior click closure, one on the posterior click closure) that help to shed some light on our understanding of the underlying representation of clicks. In the first of these studies, the so-called Back Vowel Constraint (BVC; a constraint that states that certain click types only occur before back vowels, while other click types co-occur freely with all vowels) in N|uu is analyzed in terms of differences in tongue shape in the different categories of clicks. In the second study, stiffness is identified as an articulatory parameter in N|uu. Finally, in Chapter 6, a synthesis of the new insights gained in the previous chapters is attempted in the form of a novel scheme for categorizing and transcribing clicks. In this context, the categorical terms deep concave vs. shallow concave are introduced for the systematic tongue shape differences in clicks, and the terms tense vs. lax are proposed to capture the categorical effect of articulatory stiffness in clicks

Pharyngealization in Libyan (Tripoli) Arabic: an instrumental study.

This thesis aims to study the phenomenon of pharyngealization in Arabic, in the dialect of Tripoli, Libya in relation to other dialects of Arabic. The term 'pharyngealization', as used in this study, refers to all the sounds whose main articulatory requisite is a constriction in the pharyngeal cavity. This is a physiological and articulatory study -based primarily on observations made on video-endoscopic and video-fluorographic recordings; spectrographic analysisq palatographic and airflow measurements also contributed. Chapter 1 states the aim and scope of this thesis. It defines the dialect studied and describes some of the main aspects of the sound system of Tripoli Arabic. Chapter 2 gives a description of the main structures and muscles and their actions that are considered to, directly or indirectly, play the major role in the production of these sounds. Chapter 3 describes the experimental techniques used in this study: a) fibreoptic endoscopy with videorecording b) X-ray recording; static, xeroradiography and videofluorography c) airflow recording by pneumotachography d) palatography e) labiography and f) spectrography. Chapter 4 deals with the pharyngeal consonants and studies certain issues related to their phonetic realizations and to the role of the epiglottis in their production. Chapter 5 describes the uvular consonants. Endoscopic observation revealed a great side wall movement of the pharynx occurring during the articulation of the uvular /q/, which takes place at a superior level in the pharynx. Chapter 6 deals with the pharyngealized consonants, divides them into primary and secondary and attempts to show that a large part of the problem in the description of these sounds stems from a phonemic split in the vowel /a:/. Chapter 7 discusses the main findings in this study and shows, among other things, that a great epiglotto-pharyngeal constriction is the main articulatory requisite in the articulation of the pharyngeal sounds in Arabic, irrespective of other factors. It also attempts to determine to what extent soft palate lowering and nasal airflow are coterminous with the articulation of the pharyngeal sounds

Dutch Rhotic Allophony, Coda Weakening, and the Phonetics-Phonology Interface

Evidence is presented that suggests that articulation should be considered separately from acoustics (or the auditory impression) in investigations of the interface between phonetics and phonology. We use Ultrasound Tongue Imaging to show that onset and coda versions of Dutch /r/ can have secondary articulations, categorical allophones, and subtle or covert articulations which have few acoustic implications. Covert rhotic (retroflex) articulation was observed in one speaker, who displayed acoustic derhoticisation. We also consider this finding in relation to ongoing work in Scottish English.caslpub2745pu

An exploration of the rhythm of Malay

In recent years there has been a surge of interest in speech rhythm. However we still lack a clear understanding of the nature of rhythm and rhythmic differences across languages. Various metrics have been proposed as means for measuring rhythm on the phonetic level and making typological comparisons between languages (Ramus et al, 1999; Grabe & Low, 2002; Dellwo, 2006) but the debate is ongoing on the extent to which these metrics capture the rhythmic basis of speech (Arvaniti, 2009; Fletcher, in press). Furthermore, cross linguistic studies of rhythm have covered a relatively small number of languages and research on previously unclassified languages is necessary to fully develop the typology of rhythm. This study examines the rhythmic features of Malay, for which, to date, relatively little work has been carried out on aspects rhythm and timing. The material for the analysis comprised 10 sentences produced by 20 speakers of standard Malay (10 males and 10 females). The recordings were first analysed using rhythm metrics proposed by Ramus et. al (1999) and Grabe & Low (2002). These metrics (∆C, %V, rPVI, nPVI) are based on durational measurements of vocalic and consonantal intervals. The results indicated that Malay clustered with other so-called syllable-timed languages like French and Spanish on the basis of all metrics. However, underlying the overall findings for these metrics there was a large degree of variability in values across speakers and sentences, with some speakers having values in the range typical of stressed-timed languages like English. Further analysis has been carried out in light of Fletcher’s (in press) argument that measurements based on duration do not wholly reflect speech rhythm as there are many other factors that can influence values of consonantal and vocalic intervals, and Arvaniti’s (2009) suggestion that other features of speech should also be considered in description of rhythm to discover what contributes to listeners’ perception of regularity. Spectrographic analysis of the Malay recordings brought to light two parameters that displayed consistency and regularity for all speakers and sentences: the duration of individual vowels and the duration of intervals between intensity minima. This poster presents the results of these investigations and points to connections between the features which seem to be consistently regulated in the timing of Malay connected speech and aspects of Malay phonology. The results are discussed in light of current debate on the descriptions of rhythm