Plosive Voicing Research Articles

Laryngeal contrast and sound change: The production and perception of plosive voicing and co-intrinsic pitch

Abstract: Inspired by Beddor 2009, this article explores whether and how trading relations between coarticulatory source and effect may serve as a precursor for sound change. It aims at extending the case of vowel nasalization examined by Beddor to the relationship between closure voicing (source) and co-intrinsic pitch (effect). Through four production and perception studies, we show that the inverse source-effect relation observed for vowel nasalization is not found in the voicing contrast of French, a true-voicing language. Instead, we propose that the phonologization of co-intrinsic pitch (a.k.a. tonogenesis) originates from spontaneous devoicing (a production bias), which subsequently triggers an upweighting of pitch (a perceptual adaptation strategy).*

Laryngeal contrast and sound change: The production and perception of plosive voicing and co-intrinsic pitch: Supplementary material

Laryngeal contrast and sound change: The production and perception of plosive voicing and co-intrinsic pitch: Supplementary material

Flexibility and evolution of cue weighting after a tonal split: an experimental field study on Tamang

Abstract We conducted a perception experiment in the field to examine the synchronic consequences of a tonal split in Risiangku Tamang (Tibeto-Burman). Proto-Tamang was a two-tone language with three series of plosives and two series of continuants. The merger of its continuants provoked a split of the original two tones into four, two high and two low, which combine pitch and phonation features. The quasi-merger of the voiced and voiceless plosives left sporadic remnants of initial plosive voicing in low tone syllables. A previous production study has shown that speakers use pitch and phonation features concomitantly to distinguish high from low tones, while producing initial plosive voicing only marginally with low tones. The present perception study establishes the preeminence of the pitch cue, but also confirms the effective use of the two older cues in tone identification. An apparent-time analysis shows the phonation cue to be less used by younger speakers, in keeping with the historical evolution. The use of the residual voicing of plosives, instead of decreasing with younger speakers, is shown to increase. This result could be explained by an increased contact of the young generation with Nepali, a toneless Indo-Aryan language with a four-way initial plosive contrast.

Acoustic correlates of plosive voicing in Madurese.

Madurese, a Malayo-Polynesian language of Indonesia, is of interest both areally and typologically: it is described as having a three-way laryngeal contrast between voiced, voiceless unaspirated, and voiceless aspirated plosives, along with a strict phonotactic restriction on consonant voicing-vowel height sequences. An acoustic analysis of Madurese consonants and vowels obtained from the recordings of 15 speakers is presented to assess whether its voiced and aspirated plosives might share acoustic properties indicative of a shared articulatory gesture. Although voiced and voiceless aspirated plosives in word-initial position pattern together in terms of several spectral balance measures, these are most likely due to the following vowel quality, rather than aspects of a shared laryngeal configuration. Conversely, the voiceless (aspirated and unaspirated) plosives share multiple acoustic properties, including F0 trajectories and overlapping voicing lag time distributions, suggesting that they share a glottal aperture target. The implications of these findings for the typology of laryngeal contrasts and the historical evolution of the Madurese consonant-vowel co-occurrence restriction are discussed.

Young vs. old Koreans’ vowel insertion after word-final English and French postvocalic plosives: A case of contact-induced borrowing change

This paper explores whether young vs. old Koreans’ vowel insertion after word-final English and French postvocalic plosives has changed or not. For this purpose, we conducted a perception experiment wherein 40 Koreans who were born before 1960 and another 40 Koreans who were born after 1989 were recruited with 20 male and 20 female subjects in each group. The results show that the release of plosives and the voicing of unreleased plosives are key variables for vowel insertion in both age groups. In addition, our young Koreans have no significant difference in vowel insertion after word-final English and French plosives, regardless of whether the plosives are released or unreleased, regardless of whether they are voiceless or voiced and regardless of whether they are preceded by the tense vowel [aI], as in English stimuli, or by the non-tense vowel [a], as in the French stimuli. On the other hand, our old Koreans have differences in vowel insertion after the non-native plosives in the examined contexts, depending on whether the plosives are English or French.Based on the results, we propose that vowel insertion in accordance with the plosive release and the voicing of unreleased plosives in the two groups is accounted for by Korean syllable structure with generational differences made by how two effects – the plosive voicing effect and the vowel-tenseness effect – are involved. We also propose that no significant difference in vowel insertion after word-final English and French plosives in the young group is a case of contact-induced borrowing change resulting from the English/French contact differences over time in Korean society.

Plosive (de-)voicing and f0 perturbations in Tokyo Japanese: Positional variation, cue enhancement, and contrast recovery

This study addresses the two-way laryngeal contrast of plosives in Tokyo Japanese, which is commonly analyzed as a “true voicing” language. We examine how voicing-related properties of the plosive and f0 of the following vowel varied with the position in the word and in the sentence. We compare word-initial with word-medial positions for words in citation (between two pauses) and for two prosodic conditions in a carrier sentence: with vs. without a preceding pause. In word-initial position, unlike in a typical “true-voicing” language such as French, voiced plosives in Tokyo Japanese show a high devoicing rate, while voiceless plosives are moderately aspirated. A combination of VOT and f0 of the following vowel is used to distinguish the two plosive series. In word-medial position, voiced plosives are frequently prevoiced and voiceless plosives are unaspirated, while f0 does not differ after the two plosive series. This positional variation suggests that the onset-induced f0 effect is enhanced in word-initial position, where the VOT cue is not sufficient, but not in word-medial position, where the plosive voicing contrast is robustly marked by presence vs. absence of phonetic voicing. The differential use of cues in different environments in Tokyo Japanese provides another piece of evidence for the complexity of phonetic implementations of the voicing contrast. Finally, we discuss the enhancement of f0 perturbations as a source of a potential tonal development and ask whether such a development would take place in Tokyo Japanese.

Plosive voicing acoustics and voice quality in Yerevan Armenian

Yerevan Armenian is a variety of Eastern Armenian with a three-way voicing contrast that includes voiced, voiceless unaspirated, and voiceless aspirated stops, but previous work has not converged on a description of how voice quality is involved in the contrast. We demonstrate how voice quality can be assessed in a two-dimensional acoustic space using a spectral tilt measure in conjunction with a measure of spectral noise. Eight speakers produced a list of words with prevocalic word-initial and postvocalic word-final plosives. The results suggest that Yerevan Armenian has breathy-voiced plosives which are produced with closure voicing and a relatively spread glottis that is maintained into a following vowel. These qualitatively differ from some Indic ones in that they do not have an extended interval of voiced aspiration after the closure. For the voiceless unaspirated plosives, most speakers produced acoustically modal voiceless plosives, although two showed evidence for some glottal constriction and tensing. Many acoustic cues contribute to overall reliable discriminability of the three-way contrast in both initial and final position. Nevertheless, closure voicing intensity and aspiration duration together provide a robust separation of the three categories in both positions. We also find that back vowels are fronted after the breathy-voiced plosives, which supports a historical analysis in which early Armenian voiced stops were also breathy, rather than plain voiced.

Prosodic Contrasts and Segmental Analysis in Himalayan Languages

The connection between pitch, phonation and plosive voicing has been observed in many of the languages of the world, including those of the Himalayas. The paper examines different analyses of largely phonetically similar data from various Tibetan and Tamangic languages, comparing and evaluating the substantially different analyses offered in different descriptive traditions, arguing that principles of economy and descriptive adequacy allow us to choose between alternative analyses for many languages that have been described with different types of contrasts involving plosive manner and pitch height.

Plosive voicing in Afrikaans: Differential cue weighting and tonogenesis

This study documents the relation between f0 and prevoicing in the production and perception of plosive voicing in Afrikaans. Acoustic data show that Afrikaans speakers differed in how likely they were to produce prevoicing to mark phonologically voiced plosives, but that all speakers produced large and systematic f0 differences after phonologically voiced and voiceless plosives to convey the contrast between the voicing categories. This pattern is mirrored in these same participants’ perception: although some listeners relied more than others on prevoicing as a perceptual cue, all listeners used f0 (especially in the absence of prevoicing) to perceptually differentiate historically voiced and voiceless plosives. This variation in the speech community is shown to be generationally structured such that older speakers were more likely than younger speakers to produce prevoicing, and to rely on prevoicing perceptually. These patterns are consistent with generationally determined differential cue weighting in the speech community and with an ongoing sound change in which the original consonantal voicing contrast is being replaced by a tonal contrast on the following vowel.

F0 and plosive voicing in Afrikaans

Afrikaans plosives are traditionally described as contrasting in voicing ([b d] vs. [p t]). Coetzee et al. (2014, J. Acoust. Soc. Am. 135, 2421), however, showed that the voicing contrast is collapsing word-initially, with voiced plosives merging with voiceless plosives. They also found that voicing loss does not result in loss of lexical contrast, which is preserved on the following vowel (high f0 after historically voiceless and low f0 after historically voiced plosives). That study investigated word-initial plosives, leaving unanswered whether word-medial plosives are also devoicing. The current study addresses this question. Acoustic analysis of data collected from nine Afrikaans speakers replicated the results of Coetzee et al. for word-initial plosives. For word-medial plosives, a robust voicing contrast was found along with a post-plosive f0 difference. The f0 difference in medial position was comparable to that in initial position in both magnitude and duration, and extended throughout the vowel. While lexical contrasts are hence cued by only f0 word initially, they are differentiated by both plosive voicing and the f0 of the following vowel word medially. The relevance of these results for theories of sound change and theories of phonological contrast will be discussed. [Work supported by NSF.]

Perception Abilities of L1 Cypriot Greek Listeners - Types of Errors Involving Plosive Consonants in L2 English.

This paper investigates the difficulties adult second language (L2) users of English encounter with plosive consonants in the L2. It presents the results of a task examining the acquisition of plosive voicing contrasts by college students with Cypriot Greek (CG) linguistic background. The task focused on the types of errors involving plosive consonants indicating that performance was significantly better in the voiceless plosive category. Participants were able to perceive voiced plosives but they treated such instances as a /nasal+voiced plosive/ sequence. Therefore, the question raised concerns different phonological contrasts realised through similar phonetic cues. The patterns observed suggested that this gap between phonetic cues and phonological contrast might explain why CG users have difficulties perceiving voiced English plosives. In this context, voice onset time (VOT) differences between the L1 and L2 are of crucial importance. In English, voiced plosives are characterised by short lag VOT while their voiceless counterparts fall within the long lag VOT continuum. The same phonetic contrast is used in CG to differentiate between single and geminate voiceless plosives. The results are discussed in relation to the frameworks of second language phonology and speech perception suggesting that the difficulties faced by the L2 listeners support the operation of a phonetic-phonological challenge.

Exploring dyslexics' phonological deficit III: foreign speech perception and production

This study investigates French dyslexic and control adult participants' ability to perceive and produce two different non-native contrasts (one segmental and one prosodic), across several conditions varying short-term memory load. For this purpose, we selected Korean plosive voicing (whose categories conflict with French ones) as the segmental contrast and lexical stress as the prosodic contrast (French does not use contrastive lexical stress). We also used a French (native) segmental contrast as a control. Tasks were either auditory discrimination or repetition of CVCV nonsense words. Short-term memory load was varied by presenting the stimuli either in isolation, in sequences of two, or in sequences of three. Our results show overall few differences between dyslexic and control participants. In particular, dyslexic participants performed similarly to controls in all tasks involving Korean plosives, whether in discrimination or in production, and regardless of short-term memory load. However, some group differences emerged with respect to lexical stress, in the discrimination task at greater short-term memory load. Various analyses suggest that dyslexic participants' difficulties are due to the meta-phonological nature of the task and to short-term memory load.

Dysarthria and Friedreich's ataxia: what can intelligibility assessment tell us?

Friedreich's ataxia is one of the most common hereditary disorders of the nervous system. Dysarthria is a pervasive symptom of Friedreich's ataxia, yet the clinical presentation of speech symptoms remains poorly understood, leaving clinicians without the evidence required to develop therapy interventions. The research reported herein had three aims: the first was to document the severity of the intelligibility deficit associated with Friedreich's ataxia dysarthria; the second was to document the phonetic profile of the intelligibility deficit; and the third was to use the results of the phonetic profile to estimate the motor control mechanisms and neurological substrates implicated in Friedreich's ataxia dysarthria. Eleven adult males with Friedreich's ataxia were recruited. Intelligibility was assessed using a single-word multiple-choice task completed by ten listeners. Intelligibility severity ratings ranged from mild to severe. The majority of subjects fell into the mild category. The phonetic errors revealed a distinctive profile, with word-final plosive voicing contrast representing the highest source of error. Involvement of cerebro-cerebellar loops was considered to be compatible with the profile results. Friedreich's ataxia dysarthria has a distinctive phonetic profile and contains subgroups of different severity. High sources of error identified in the phonetic profile should be considered when developing targets for therapy intervention. Neurological substrates are considered to vary across individuals and to include involvement of cerebro-cerebellar loops. Further research involving acoustic analysis of final plosive voicing contrasts would provide further insights into the neurological substrates involved.

Voicing status of word final plosives in Friedreich's Ataxia dysarthria

In a previous study, the authors identified final plosive voicing contrast as the highest single error source in dysarthria associated with Friedreich's Ataxia in a group of Irish English‐speaking participants. This study aimed to determine the acoustic features underlying misperceptions of voicing status and implications for clinical management. Words with final plosives were extracted from recordings of ten speakers with Friedreich's Ataxia. Various measures of the syllable rhyme were compared with intelligibility scores. Vowel duration, voicing in the closure, F1 frequency at mid‐vowel and a drop in F1 at vowel termination accounted for 58% of the variance in the relevant intelligibility scores, with vowel duration being most heavily implicated. While inappropriate vowel duration is the factor most likely to lead to misperceptions of final plosive voicing status, other factors may overcome its effect. Therapeutic intervention with this population should be based on a comparison of intelligibility assessment with acoustic measurement.

An exploratory study into perception of acoustic speech cues by hearing-impaired adults.

The aims of the present study were to assess discrimination and identification based on two classes of acoustic cue by adults with acquired sensorineural hearing impairment. Eight hearing-impaired and eight normally hearing adults were asked to identify and discriminate two different sets of speech stimuli. A plosive voicing continuum (coat/goat) varied in voice onset time. The plosive place of articulation continuum (date/gate) varied in burst spectra and second formant transition. Subjects were tested in the unaided condition with the exception of one hearing-impaired subject for whom speech was completely inaudible without a hearing aid. There was no significant between-group difference in discrimination or identification of the voicing contrast. There was no significant between-group difference in identification of stimuli varying by place of articulation. However, three of the eight hearing-impaired subjects were very poor at identification. The hearing-impaired subjects also showed significantly impaired place of articulation discrimination. Both measures were significantly correlated with threshold at 2000 Hz. The results support the view that hearing impairment can have different effects on perception of different acoustic contrasts and on different psychophysical tasks.