The quantitative prevalence of creaky voice (vocal fry) in varieties of English: A systematic review of the literature.

BACKGROUND/AIM: It is widely believed that 'creaky voice' ('creak', 'vocal fry', 'glottal fry') is increasingly prevalent among some English speakers, particularly among young American women. Motivated by the widespread and cross-disciplinary interest in the phenomenon, this paper offers a systematic review of peer-reviewed research (up to January 2019) on the prevalence of creaky voice in varieties of English. The review aimed to understand whose and what speech has been studied, how creaky voice prevalence has been measured, and what the findings collectively reveal. METHOD: Literature was located by searching four electronic databases (ProQuest, PubMed, SCOPUS, Web of Science) and the proceedings of two recurrent conferences ('ICPhS' and 'SST'). Studies were included if they reported the prevalence of creaky voice in naturalistic samples of English spoken by vocally-healthy speakers. Reference lists of included studies were cross-checked. RESULTS: Only ten studies meeting inclusion criteria were identified. All studies sampled a small number of speakers and/or short durations of speech. Nine were recent studies of American-English speakers, and many of these sampled young, female, college students. Across the ten studies, creaky voice was detected using three types of methods, and prevalence was calculated using five different formulae. The findings show that prevalence varies across groups, individuals, and contexts. However, the precise nature of this variability remains unclear due to the scarcity and methodological heterogeneity of the research. CONCLUSIONS: This paper illustrated the application of systematic literature review methods in sociophonetic research-a field in which such methods are not common. The review found that creaky voice prevalence in English is not well understood, and that widespread claims of its recent increase among young American women have not been empirically confirmed. A number of specific limitations in the existing research are highlighted, which may serve as a guide for future research design.

Voice Onset Time and beyond: Exploring laryngeal contrast in 19 languages.

In this special collection entitled Marking 50 Years of Research on Voice Onset Time and the Voicing Contrast in the World's Languages, we have compiled eleven studies investigating the voicing contrast in 19 languages. The collection provides extensive data obtained from 270 speakers across those languages, examining VOT and other acoustic, aerodynamic and articulatory measures. The languages studied may be divided into four groups: 'aspirating' languages with a two-way contrast (English, three varieties of German); 'true voicing' languages with a two-way contrast (Russian, Turkish, Brazilian Portuguese, two Iranian languages Pashto and Wakhi); languages with a three-way contrast (Thai, Vietnamese, Khmer, Yerevan Armenia, three Indo-Aryan languages, Dawoodi, Punjabi and Shina, and Burushaki spoken in India); and Indo-Aryan languages with a more than three-way contrast (Jangli and Urdu with a four-way contrast, and Sindhi and Siraiki with a five-way contrast). We discuss the cross-linguistic data, focusing on how much VOT alone tell s us above the voicing contrast in these languages, and what other phonetic dimensions (such as consonant-induced F0 and voice quality) are needed for a complete understanding of laryngeal contrast in these languages. Implications for various issues emerge: universal phonetic feature systems, effects of language contact on linguistic levelling, and the relation between laryngeal contrast and supralaryngeal articulation. The cross-linguistic VOT data also lead us to discuss how the distribution of VOT as measured acoustically may allow us to infer the underlying articulation and how it might be approached in gestural phonologies. The discussion on these multiple issues sparks new questions to be resolved, and provide indications of where the field may be best directed in exploring laryngeal contrast in voicing in the world's languages.

Missed Connections at the Junction of Sociolinguistics and Speech Processing.

In recent years, significant momentum has built up in efforts to integrate the social with the cognitive in theoretical models of speech production/processing and phonological representation. While acknowledging these advances, we argue that what limits our ability to elaborate models of processing and representation in which social-indexical properties of speech are effectively integrated is that we remain some way from fully understanding how these properties are manifested within spoken interaction in the first place. We explore some of these limitations, drawing on data from a study of sociophonetic variability in a population of speakers of Australian English. We discuss issues relating to methods for capturing variability in the realization of vowels and consonants, and we highlight the pivotal role of speech style and the challenges that this raises for models of production and processing.

Cross-language differences in fundamental frequency range: a comparison of English and German.

This paper presents a systematic comparison of various measures of f0 range in female speakers of English and German. F0 range was analyzed along two dimensions, level (i.e., overall f0 height) and span (extent of f0 modulation within a given speech sample). These were examined using two types of measures, one based on "long-term distributional" (LTD) methods, and the other based on specific landmarks in speech that are linguistic in nature ("linguistic" measures). The various methods were used to identify whether and on what basis or bases speakers of these two languages differ in f0 range. Findings yielded significant cross-language differences in both dimensions of f0 range, but effect sizes were found to be larger for span than for level, and for linguistic than for LTD measures. The linguistic measures also uncovered some differences between the two languages in how f0 range varies through an intonation contour. This helps shed light on the relation between intonational structure and f0 range.