The Control of Vocal Pitch in Human Laryngeal Motor Cortex.

In speech, the highly flexible modulation of vocal pitch creates intonation patterns that speakers use to convey linguistic meaning. This human ability is unique among primates. Here, we used high-density cortical recordings directly from the human brain to determine the encoding of vocal pitch during natural speech. We found neural populations in bilateral dorsal laryngeal motor cortex (dLMC) that selectively encoded produced pitch but not non-laryngeal articulatory movements. This neural population controlled short pitch accents to express prosodic emphasis on a word in a sentence. Other larynx cortical representations controlling voicing and longer pitch phrase contours were found at separate sites. dLMC sites also encoded vocal pitch during a non-speech singing task. Finally, direct focal stimulation of dLMC evoked laryngeal movements and involuntary vocalization, confirming its causal role in feedforward control. Together, these results reveal the neural basis for the voluntary control of vocal pitch in human speech. VIDEO ABSTRACT.

Voice Onset Time of Greek Stops Productions by Greek Children with Cochlear Implants and Normal Hearing.

INTRODUCTION: Research on voice onset time (VOT) production of stops in children with CI versus NH has reported conflicting results. Effects of age and place of articulation on VOT have not been examined for children with CI. The purpose of this study was to examine VOT production by Greek-speaking children with CI in comparison to NH controls, with a focus on the effects of age, type of stimuli, and place of articulation. METHODS: Participants were 24 children with CI aged from 2;8 to 13;3 years and 24 age- and gender-matched children with NH. Words were elicited via a picture-naming task, and nonwords were elicited via a fast mapping procedure. RESULTS: For voiced stops, children with CI showed longer VOT than children with NH, whereas VOT for voiceless stops was similar to that of NH peers. Also, in both voiced and voiceless stops, the VOT differed as a function of age and place of articulation across groups. Differences as a function of stimulus type were only noted for voiced stops across groups. CONCLUSIONS: For the voiced stop consonants, which demand more articulatory effort, VOT production in children with CI was longer than in children with NH. For the voiceless stop consonants, VOT production in children with CI is acquired at a young age.

Stop contrast acquisition in child Kriol: Evidence of stable transmission of phonology post Creole formation.

Many Aboriginal Australian communities are undergoing language shift from traditional Indigenous languages to contact varieties such as Kriol, an English-lexified Creole. Kriol is reportedly characterised by lexical items with highly variable phonological specifications, and variable implementation of voicing and manner contrasts in obstruents (Sandefur, 1986). A language, such as Kriol, characterised by this unusual degree of variability presents Kriol-acquiring children with a potentially difficult language-learning task, and one which challenges the prevalent theories of acquisition. To examine stop consonant acquisition in this unusual language environment, we present a study of Kriol stop and affricate production, followed by a mispronunciation detection study, with Kriol-speaking children (ages 4-7) from a Northern Territory community where Kriol is the lingua franca. In contrast to previous claims, the results suggest that Kriol-speaking children acquire a stable phonology and lexemes with canonical phonemic specifications, and that English experience would not appear to induce this stability.

Substitution voicing index: towards improved speech assessment in patients who have undergone laryngeal oncosurgery.

This study aimed to develop a multidimensional model for the evaluation of substitution voicing (SV) after laryngeal oncosurgery. The study group consisted of 121 adult male individuals: 59 patients with SV after laryngeal oncosurgery (endolaryngeal cordectomy, partial laryngectomy, total laryngectomy with tracheoesophageal prosthesis) and 62 healthy controls. A multidimensional protocol for the assessment of SV included, 1) self-reported speech evaluation with a short version of the Speech Handicap Index, 2) auditory-perceptual assessment, and 3) acoustic speech analysis using AMPEX® (Auditory Model Based Pitch Extractor) software. Moderate correlations were observed between parameters from self-reported auditory-perceptual and acoustic speech analysis domains. The multidimensional Substitution Voicing Index (SVI), including markers from these domains, was elaborated by using linear stepwise regression to determine the optimal set of parameters for categorising SV patients. The lowest mean SVI score was revealed in the control subgroup corresponding to the normal speech, followed by cordectomy subgroup and partial laryngectomy subgroup. The highest mean SVI score was revealed in the total laryngectomy subgroup, reflecting the most severely deteriorated quality of SV. One-way analysis of variance identified statistically significant differences between the mean SVI scores in separate subgroups. The results demonstrated the potential benefits of the SVI for a multidimensional evaluation of SV in patients after laryngeal oncosurgery.

Spasmodic dysphonia: introductory phonetic analyses.

Adductor spasmodic dysphonia (ADSD) is a neurological dystonia characterised by involuntary adductor spasms of the larynx during speech. Spasm frequency is often reported to increase during syllables that begin with voiced speech sounds, especially glottal stops. Because of its underlying physical and acoustic complexities, the voicing contrast in American English (AE) appears unlikely to interact consistently with a singular physical phenomenon like laryngeal spasm. This retrospective study investigated additional phonetic contrasts and their relationship to spasm frequency. Standardised, 144-word recordings of 36 participants with adductor spasmodic dysphonia were analysed. Productions were coded for rater-perceived syllable stress, voiced/voiceless onset, vowel/consonant onset, and word-onset place and manner of production. Phonetic contexts were compared using independent sample t-tests and Kruskal-Wallis statistics. Contexts in which spasm varied significantly included stressed/unstressed syllables, content/function words, and multisyllabic/monosyllabic words. Study results reaffirm the clinical usefulness of standardised ADSD/ABSD sentences during differential diagnosis but conflict with previous studies that report a connection between ADSD spasm and phoneme voicing.

Multi-modal imaging of the auditory-larynx motor network for voicing perception.

Voicing is one of the most important characteristics of phonetic speech sounds. Despite its importance, voicing perception mechanisms remain largely unknown. To explore auditory-motor networks associated with voicing perception, we firstly examined the brain regions that showed common activities for voicing production and perception using functional magnetic resonance imaging. Results indicated that the auditory and speech motor areas were activated with the operculum parietale 4 (OP4) during both voicing production and perception. Secondly, we used a magnetoencephalography and examined the dynamical functional connectivity of the auditory-motor networks during a perceptual categorization task of /da/-/ta/ continuum stimuli varying in voice onset time (VOT) from 0 to 40 ms in 10 ms steps. Significant functional connectivities from the auditory cortical regions to the larynx motor area via OP4 were observed only when perceiving the stimulus with VOT 30 ms. In addition, regional activity analysis showed that the neural representation of VOT in the auditory cortical regions was mostly correlated with categorical perception of voicing but did not reflect the perception of stimulus with VOT 30 ms. We suggest that the larynx motor area, which is considered to play a crucial role in voicing production, contributes to categorical perception of voicing by complementing the temporal processing in the auditory cortical regions.

Northern Raglai voicing and its relation to Southern Raglai register: evidence for early stages of registrogenesis.

Northern and Southern Raglai are two closely related Austronesian dialects (Chamic branch) spoken in south-central Vietnam. Although they are mutually intelligible, Northern Raglai is described as having a voicing contrast in onset stops, while Southern Raglai is assumed to have replaced the Chamic voicing contrast with a register contrast realized on the whole syllable (but primarily on its vowel). A production study of the two dialects confirms that Northern Raglai preserves a voicing contrast, even if most women exhibit partial devoicing of their voiced stops, and that Southern Raglai has developed a register contrast based on F1 and phonation cues at the beginning of vowels. The weights of the acoustic properties of voicing and register are similar across ages and genders, suggesting that the two laryngeal contrasts are phonetically stable. Even if there is little evidence of change in progress, a close inspection of the Northern Raglai voicing contrast reveals voicing-conditioned modulations of F1 and perturbations of phonation after partially devoiced stops that could be precursors of a register system similar to that of Southern Raglai. We argue that this is a pathway to registrogenesis and speculate about the articulatory laryngeal mechanisms that could trigger registrogenetic changes. Our data also show that the Northern Raglai voicing contrast is unstable in aspirated stops and that voiced aspirated stops typically have a partially voiceless and partially voiced aspiration.

Voicing their choices: Advance care planning with adolescents and young adults with cancer and other serious conditions.

OBJECTIVES: To determine whether engaging in advance care planning (ACP) using a formal tool, Voicing My CHOiCES (VMC), would alleviate adolescent and young adults (AYAs) anxiety surrounding ACP and increase social support and communication about end-of-life care preferences with family members and health care providers (HCPs). METHODS: A total of 149 AYAs aged 18-39 years receiving cancer-directed therapy or treatment for another chronic medical illness were enrolled at seven US sites. Baseline data included prior ACP communication with family members and HCPs and measures of generalized anxiety, ACP anxiety, and social support. Participants critically reviewed each page of VMC and then completed three pages of the document. ACP anxiety was measured again immediately after the completion of VMC pages. One month later, participants repeated anxiety and social support measures and were asked if they shared what they had completed in VMC with a family member or HCP. RESULTS: At baseline, 50.3% of participants reported that they previously had a conversation about EoL preferences with a family member; 19.5% with an HCP. One month later, 65.1% had subsequently shared what they wrote in VMC with a family member; 8.9% shared with an HCP. Most (88.6%) reported they would not have had this conversation if not participating in the study. No significant changes occurred in social support. There was an immediate drop in anxiety about EoL planning after reviewing VMC which persisted at 1 month. Generalized anxiety was also significantly lower 1 month after reviewing VMC. SIGNIFICANCE OF RESULTS: Having a document specifically created for AYAs to guide ACP planning can decrease anxiety and increase communication with family members but not necessarily with HCPs. Future research should examine ways ACP can be introduced more consistently to this young population to allow their preferences for care to be heard, respected, and honored, particularly by their healthcare providers.

Idiosyncratic consonant clusters: a Farsi-speaking child with protracted phonological development.

This study presents a nonlinear phonological analysis of speech data from a Farsi-speaking child with protracted phonological development (aged 4;8) with very low accuracy on consonants. Results revealed some common phenomena (fricatives produced as stops; dorsals and non-anterior coronals produced as anterior coronals) and some uncommon phenomena (nasals produced as oral stops; voicing and devoicing of singleton obstruents in all word positions). These phenomena interacted in word-medial clusters to create an unusual sequence of two anterior-coronal or two bilabial stops, with C1 voiced and C2 voiceless, clusters which do not occur in the basic phonology of Farsi spoken by adults. We present a non-linear constraints-based analysis of the child's speech production and a plan for intervention targeting the child's special difficulties.

Effects of Glottalisation, Preceding Vowel Duration, and Coda Closure Duration on the Perception of Coda Stop Voicing.

English has multiple potential acoustic cues to coda stop voicing, including the duration of the preceding vowel, the coda closure duration, and, in some varieties, glottalisation. Glottalisation associated with coda stops appears to be a recent change to Australian English (AusE) with younger speakers using glottalisation more than older speakers in production. Here we report on a study designed to examine AusE-speaking listeners' perception of cues to coda stop voicing. Listeners were presented with audio stimuli in which preceding vowel duration, coda closure duration, and the relative proportions of the rhyme that these occupy were manipulated and co-varied with the presence or absence of glottalisation. The results show that listeners used preceding vowel duration to cue coda stop voicing, and that coda closure duration was a weaker cue to voicing when not varied in conjunction with preceding vowel duration. In addition, glottalisation facilitated increased perception of coda voicelessness, even when paired with very long preceding vowels, which otherwise signal coda voicing. Although age-related differences in production have previously been reported, we found that both older and younger listeners used glottalisation similarly in perception. These results may provide support for a sound change led by a shift in perception.

Acoustic cues to coda stop voicing contrasts in Australian English-speaking children.

While voicing contrasts in word-onset position are acquired relatively early, much less is known about how and when they are acquired in word-coda position, where accurate production of these contrasts is also critical for distinguishing words (e.g., dog vs. dock). This study examined how the acoustic cues to coda voicing contrasts are realized in the speech of 4-year-old Australian English-speaking children. The results showed that children used similar acoustic cues to those of adults, including longer vowel duration and more frequent voice bar for voiced stops, and longer closure and burst durations for voiceless stops along with more frequent irregular pitch periods. This suggests that 4-year-olds have acquired productive use of the acoustic cues to coda voicing contrasts, though implementations are not yet fully adult-like. The findings have implications for understanding the development of phonological contrasts in populations for whom these may be challenging, such as children with hearing loss.

Precision of voicing perceptual identification is altered in association with voice-onset time production changes.

There is ample evidence that motor learning changes the function of perceptual systems. Previous studies examining the interactions between speech production and perception have shown that the discrimination of phonetic contrasts characterized by the difference in articulatory place features is altered following their production changes caused by the perturbation of auditory feedback. The present study focused on a voiced-voiceless contrast in stop consonants, which is characterized by a temporal articulatory parameter, voice-onset time (VOT). In the experiment, we manipulated the participants' motor functions concerning VOT using a cross-categorical auditory feedback (CAF) paradigm (Mitsuya et al. in J Acoust Soc Am 135:2986-2994, 2014), in which a pre-recorded syllable sound starting with a voiced stop consonant (/da/) was fed back simultaneously with the participant's utterance of a voiceless stop consonant (/ta/), and vice versa. The VOT difference between /da/ and /ta/ productions was increased by the CAF, which is consistent with the result of Mitsuya's study. In addition, we conducted perceptual identification tasks of /da/-/ta/ continuum stimuli varying in VOT before and after the CAF task, and found that the identification function became sharper after as compared to before the CAF task. A significant positive correlation between such production and perception changes was also found. On the basis of these results, we consider that the change in motor function concerning VOT affected voiced-voiceless perceptual processing. The present study is the first to show the involvement of the speech production system in the perception of phonetic contrasts characterized by articulatory temporal features.

Temporal control in the voicing contrast: Evidence from surgery-related apraxia of speech.

The goal of this study was to investigate the phonetic realisation of the voicing feature in two tumour resection-related Spanish speakers with apraxia of speech. Temporal parameters related to the phonological contrast of voicing in Spanish have been analysed for intervocalic voiced and voiceless obstruents embedded in isolated words and nonwords, and compared with data collected from healthy speakers. Results indicate that in devoiced productions, where VOT values fitted the 'voiceless stops' category, vowel duration values matched those of voiced stops and suggested the preservation of contextual voicing cues. An attempt at preserving a consonant/vowel duration ratio consistent with aerodynamic predictions for voicing contrast has been observed in apraxic correct production as well as in devoicing errors, but not in the control group, which could be interpreted as a compensatory mechanism.

Phonetic detail and lateralization of reading-related inner speech and of auditory and somatosensory feedback processing during overt reading.

Phonetic detail and lateralization of inner speech during covert sentence reading as well as overt reading in 32 right-handed healthy participants undergoing 3T fMRI were investigated. The number of voiceless and voiced consonants in the processed sentences was systematically varied. Participants listened to sentences, read them covertly, silently mouthed them while reading, and read them overtly. Condition comparisons allowed for the study of effects of externally versus self-generated auditory input and of somatosensory feedback related to or independent of voicing. In every condition, increased voicing modulated bilateral voice-selective regions in the superior temporal sulcus without any lateralization. The enhanced temporal modulation and/or higher spectral frequencies of sentences rich in voiceless consonants induced left-lateralized activation of phonological regions in the posterior temporal lobe, regardless of condition. These results provide evidence that inner speech during reading codes detail as fine as consonant voicing. Our findings suggest that the fronto-temporal internal loops underlying inner speech target different temporal regions. These regions differ in their sensitivity to inner or overt acoustic speech features. More slowly varying acoustic parameters are represented more anteriorly and bilaterally in the temporal lobe while quickly changing acoustic features are processed in more posterior left temporal cortices. Furthermore, processing of external auditory feedback during overt sentence reading was sensitive to consonant voicing only in the left superior temporal cortex. Voicing did not modulate left-lateralized processing of somatosensory feedback during articulation or bilateral motor processing. This suggests voicing is primarily monitored in the auditory rather than in the somatosensory feedback channel. Hum Brain Mapp 38:493-508, 2017. © 2016 Wiley Periodicals, Inc.

A perceptual study of the voicing feature of stop consonants after type II and III laser cordectomies.

This article deals with the intelligibility of stop consonants in onset position (initial and intervocalic) as pronounced by 10 French speakers treated by a type II or III cordectomy. These surgeries cause a less efficient glottal closure and a vibratory asymmetry. The voicing contrast in consonants may be altered. The patients' vocal samples were made up of non-words of the CVCVCVC type, where C = /p, t, k, b, d, g/ and V = /a, i, u/(n = 360), and were given to 22 French listeners for evaluation. Two identification tests were created and the listeners were asked to choose the consonants they thought they recognized (n = 7920). The results were presented in the form of a confusion matrix highlighting possible confusions of voicing and/or places of articulation. We showed high identification rates of consonants, which revealed an intact voicing contrast in this dysphonic population.

Realisation of voicing by French-speaking CI children after long-term implant use: An acoustic study.

Studies of speech production in French-speaking cochlear-implanted (CI) children are very scarce. Yet, difficulties in speech production have been shown to impact the intelligibility of these children. The goal of this study is to understand the effect of long-term use of cochlear implant on speech production, and more precisely on the coordination of laryngeal-oral gestures in stop production. The participants were all monolingual French children: 13 6;6- to 10;7-year-old CI children and 20 age-matched normally hearing (NH) children. We compared /p/, /t/, /k/, /b/, /d/ and /g/ in word-initial consonant-vowel sequences, produced in isolation in two different tasks, and we studied the effects of CI use, vowel context, task and age factors (i.e. chronological age, age at implantation and duration of implant use). Statistical analyses show a difference in voicing production between groups for voiceless consonants (shorter Voice Onset Times for CI children), with significance reached only for /k/, but no difference for voiced consonants. Our study indicates that in the long run, use of CI seems to have limited effects on the acquisition of oro-laryngeal coordination needed to produce voicing, except for specific difficulties located on velars. In a follow-up study, further acoustic analyses on vowel and fricative production by the same children reveal more difficulties, which suggest that cochlear implantation impacts frequency-based features (second formant of vowels and spectral moments of fricatives) more than durational cues (voicing).

Voicing Assimilation in Czech and Slovak Speakers of English: Interactions of Segmental Context, Language and Strength of Foreign Accent.

This study focuses on voicing assimilation across word boundaries in the speech of second language (L2) users. We compare native speakers of British English to speakers of two West Slavic languages, Czech and Slovak, which, despite their many similarities, differ with respect to voicing assimilation rules. Word-final voicing was analysed in 30 speakers, using the static value of voicing percentage and the voicing profile method. The results of linear mixed-effects modelling suggest an effect of first language (L1) transfer in all L2 English speaker groups, with the tendency to assimilate being correlated with the strength of foreign accent. Importantly, the two language groups differed in assimilation strategies before sonorant consonants, as a clear effect of L1-based phonetic influence.

The Effects of Language Experience and Speech Context on the Phonetic Accommodation of English-accented Spanish Voicing.

Native speakers of Spanish with different amounts of experience with English classified stop-consonant voicing (/b/ versus /p/) across different speech accents: English-accented Spanish, native Spanish, and native English. While listeners with little experience with English classified target voicing with an English- or Spanish-like voice onset time (VOT) boundary, predicted by contextual VOT, listeners familiar with English relied on an English-like VOT boundary in an English-accented Spanish context even in the absence of clear contextual cues to English VOT. This indicates that Spanish listeners accommodated English-accented Spanish voicing differently depending on their degree of familiarization with the English norm.

Longitudinal observations of typical English voicing acquisition in a 2-year-old child: Stability of the contrast and considerations for clinical assessment.

Early assessment of phonetic and phonological development requires knowledge of typical versus atypical speech patterns, as well as the range of individual developmental trajectories. The nature of data reporting in previous literature on typical voicing acquisition left aspects of the developmental process unclear and limited clinical applicability. This work extends a previous four-month group study to present data for one child over 12 months. Words containing initial /b p d t/ were elicited from a monolingual English-speaking 2-year-old child biweekly for 25 sessions. Voice onset time (VOT) was measured for each stop. For each consonant and recording session, we measured range as well as accuracy, overshoot and discreteness calculated for means and individual tokens. The results underscore the value of token-by-token analyses. They further reveal that typical development may involve an extended period of fluctuating voicing patterns, suggesting that the voiced/voiceless contrast may take months or years to stabilise.

Does Vocalization Increase the Positive Valence of Emotion?

PURPOSE: This study aims to determine if the act of voicing can have an effect on mood. DESIGN: A within-participant reversal paradigm, where each participant served as their own control. METHODS: Following a baseline condition, 40 participants (8 male, 32 female, none disclosed as other) underwent three experimental conditions: breathing, articulating, and voicing. After each condition, participants underwent a picture-viewing emotion-induction paradigm using the International Affective Picture System followed by rating their current mood and arousal. RESULTS: Immediately following the articulating condition, aversive pictures were rated as less unpleasant compared with the other conditions. Additionally, arousal levels were rated lower immediately following the articulating and voicing conditions in response to the positive pictures. CONCLUSIONS: The findings showed that the act of making speech sounds, not simply voicing by itself, may influence the way we process emotions.