Correcting the record: Phonetic potential of primate vocal tracts and the legacy of Philip Lieberman (1934-2022).

The phonetic potential of nonhuman primate vocal tracts has been the subject of considerable contention in recent literature. Here, the work of Philip Lieberman (1934-2022) is considered at length, and two research papers-both purported challenges to Lieberman's theoretical work-and a review of Lieberman's scientific legacy are critically examined. I argue that various aspects of Lieberman's research have been consistently misinterpreted in the literature. A paper by Fitch et al. overestimates the would-be "speech-ready" capacities of a rhesus macaque, and the data presented nonetheless supports Lieberman's principal position-that nonhuman primates cannot articulate the full extent of human speech sounds. The suggestion that no vocal anatomical evolution was necessary for the evolution of human speech (as spoken by all normally developing humans) is not supported by phonetic or anatomical data. The second challenge, by Boë et al., attributes vowel-like qualities of baboon calls to articulatory capacities based on audio data; I argue that such "protovocalic" properties likely result from disparate articulatory maneuvers compared to human speakers. A review of Lieberman's scientific legacy by Boë et al. ascribes a view of speech evolution (which the authors term "laryngeal descent theory") to Lieberman, which contradicts his writings. The present article documents a pattern of incorrect interpretations of Lieberman's theoretical work in recent literature. Finally, the apparent trend of vowel-like formant dispersions in great ape vocalization literature is discussed with regard to Lieberman's theoretical work. The review concludes that the "Lieberman account" of primate vocal tract phonetic capacities remains supported by research: the ready articulation of fully human speech reflects species-unique anatomy.

The Mason-Alberta Phonetic Segmenter: a forced alignment system based on deep neural networks and interpolation.

Given an orthographic transcription, forced alignment systems automatically determine boundaries between segments in speech, facilitating the use of large corpora. In the present paper, we introduce a neural network-based forced alignment system, the Mason-Alberta Phonetic Segmenter (MAPS). MAPS serves as a testbed for two possible improvements we pursue for forced alignment systems. The first is treating the acoustic model as a tagger, rather than a classifier, motivated by the common understanding that segments are not truly discrete and often overlap. The second is an interpolation technique to allow more precise boundaries than the typical 10 ms limit in modern systems. During testing, all system configurations we trained significantly outperformed the state-of-the-art Montreal Forced Aligner in the 10 ms boundary placement tolerance threshold. The greatest difference achieved was a 28.13 % relative performance increase. The Montreal Forced Aligner began to slightly outperform our models at around a 30 ms tolerance. We also reflect on the training process for acoustic modeling in forced alignment, highlighting how the output targets for these models do not match phoneticians' conception of similarity between phones and that reconciling this tension may require rethinking the task and output targets or how speech itself should be segmented.

Learning to produce and transcribe cardinal vowels: speech and language therapy students' perception of task difficulty.

Learning vowel transcription skills is crucial to function as a Speech and Language Therapist (SLT). However, vowel transcription is commonly regarded as particularly difficult and therefore often avoided. Despite the importance of accurate transcriptions, little is known about all the factors that influence the process of learning vowel transcription, which usually includes the learning of the Cardinal Vowel (CV) system. There are only a few studies that investigate how CVs are learnt and what factors lead to successful learning. The current study reports students' perceived difficulty of producing and transcribing CVs as a first step to identify how perceived difficulty affects phonetic learning. Perceived difficulty ratings for the production and transcription of 12 CVs collected from 155 students studying towards a qualification as an SLT were analysed. The results show that the classificatory features correlate with the perceived task difficulty of production and transcription. Implications for teaching are outlined.

Development of perceptual similarity and discriminability: the perception of Russian phonemes by Chinese learners.

This study explored the perceptual assimilation and discrimination of Russian phonemes by three groups of Chinese listeners with differing Russian learning experience. A perceptual assimilation task (PAT) and a perceptual discrimination test (PDT) were conducted to investigate if/how L1-L2 perceptual similarity would vary as a function of increased learning experience, and the development of assimilation-discrimination relations. The PAT was analyzed via assimilation rates, dispersion K' values, goodness ratings and assimilation patterns. Results revealed an intriguing phenomenon that the perceived Mandarin-Russian similarity first increased from naïve listeners to intermediate learners and then decreased slightly in relatively advanced learners. This suggests that L1-L2 perceptual similarity is subject to learning experience and could follow a potential "rise and fall" developmental pattern. The PDT results were mostly in line with the assimilation-discrimination correspondence with more experience bringing out better discriminability in general. Yet the overall sensitivity d' values from the Chinese groups were relatively low, implying acoustic/articulatory effects on L2 discriminability aside from perceptual assimilation. The results were discussed under the frameworks of L2 Perceptual Assimilation Model, Speech Learning Model and L2 Linguistic Perception Model.

Implementation of an automated grading tool for phonetic transcription training.

Clinical phonetic transcription is regarded as a highly specialised skill requiring hours of practice for mastery. Although this skill is a critical part of students' clinical preparation to become speech-language pathologists, students often report feeling unprepared to apply the skill in clinical practice. Previous studies suggest that increased opportunities for practice and timely feedback on transcriptions are needed in order to develop skill confidence. However, providing more opportunities for practice can be impeded by the limited resources to manage the grading of additional assignments. The purpose of this study is to show the implementation of a web-based learning management system (LMS) designed in our labs for phonetics instruction. The Automated Phonetic Transcription Grading Tool (APTgt LMS) was developed to provide a platform for assignment delivery and automated grading of transcription assignments. The APTgt LMS has three embedded IPA keyboards (basic, advanced, and full IPA) and an automated edit distance algorithm modified by phonetic alignment principles, which allows for individualised scoring and visual course-level feedback in an interactive online environment. For pilot testing, student confidence was queried before and after practice opportunities using APTgt. A concurrent mixed methods research design was used to analyse four Likert scale and three open-ended questions. Student confidence in transcribing disordered speech was found to significantly increase (p <0.001) following additional practice. Students reported concerns related to accurate transcription of disordered speech and that additional practice is still needed. Tools like APTgt can aid in facilitating student learning and increasing student confidence in applied transcription.

EPG research and therapy: further developments.

Electropalatography (EPG) has been used in the past 50 years for studying the patterns of contact between the tongue and the palate during speech production in typical speakers and those with speech disorders due to different causes. At the 7th EPG Symposium in Japan that was held online on 24 January 2021 (see: https://epg-research.sakura.ne.jp/), a panel of invited experts discussed their views regarding further developments and application of the technique. This paper provides a summary of this discussion. EPG offers information on articulation which cannot be replaced by other instrumental measures of speech. Identified areas for further hardware development are thinner EPG plates, better dental and palatal coverage, wireless connectivity, and sensors that provide additional articulatory information (e.g. tongue pressure, tongue-palate distance). EPG can serve as a resource for teaching speech disorders and phonetics. Furthermore, EPG therapy can be combined with telepractice in the speech therapy of clients with speech disorders.

Intelligibility of pseudo-whispered speech after total laryngectomy.

This study aimed to assess the intelligibility of so-called 'pseudo-whispered speech' (pseudo-WS), as produced without voice nor pulmonic airstream by some alaryngeal patients prior to rehabilitation. Several perception tests were submitted to three experienced clinicians and three naive listeners, relying on the speech samples of 20 French native speakers: 10 alaryngeal speakers, solely using pseudo-WS when starting speech therapy up to six months after total laryngectomy, and 10 control speakers, recorded in the closest speech mode available, whispered speech (WS). Experts were asked to identify consonants (C) in the /a/+C+/a/ context and to rate intelligibility, unintended additive noise, and fluency on a likert-scale, while naive listeners completed a quantitative test of intelligibility. Intelligibility of WS was found to be high, with scores ranging from 46.33/54 to 53.67/54 (median 52.5, interquartile range 2.33) for the quantitative test, and segmental intelligibility ranging from 68.75% to 94.79% (median 87.5, interquartile range 17.71). Segmental confusion affected voicing in favour of unvoiced consonants, as previously reported in the literature. By contrast, intelligibility of pseudo-WS was found to be poor, with scores ranging from 1/54 (unintelligibility) to 28.33/54 (median 8.66, interquartile range 14.67) for the quantitative test, and segmental intelligibility ranging from 3.13% to 28.13% (median 9.24, interquartile range 14.58). Segmental intelligibility was not uniformly affected: stops, labials and unvoiced consonants were better identified than other categories. Finally, a significant correlation was found between global intelligibility and articulatory precision, while unintended additive noise and fluency seemed to play no role.

Nasal patency and mandibular movement: clinical application in prosthodontics.

This case report describes a patient with a primary concern of persistent mandibular deviation during speech who experienced clinically significant improvement (mandibular movement without deviation) after improvements to nasal resistance. At the initial consultation, temporary placement of a nasal valve dilator immediately eliminated the patient's mandibular deviation during speech, indicating the need for referral to an otolaryngologist. The patient was also provided with a dental appliance to address secondary concerns of temporomandibular joint noises and cervicofacial pain. Although the dental treatment provided some relief, resolution of the patient's mandibular deviation during speech did not occur until after nasal surgery was completed. This case illustrates the importance and effects of nasal resistance and nasal patency to obtaining a reproducible mandibular position.

Rethinking the phonetics of baby-talk: Differences across Canada and Vanuatu in the articulation of mothers' speech to infants.

Infant-directed speech (IDS) is phonetically distinct from adult-directed speech (ADS): It is typically considered to have special prosody-like higher pitch and slower speaking rates-as well as unique speech sound properties, for example, more breathy, hyperarticulated, and/or variable consonant and vowel articulation. These phonetic features are widely observed in the IDS of caregivers from urbanized contexts who speak a handful of very well-researched languages. Yet studies with more diverse socio-cultural and linguistic samples show that this "typical" IDS prosody is not consistently observed across cultures. We extended cross-cultural work by examining IDS speech segment articulation, which-like prosody-is also thought to be a characteristic phonetic feature of IDS that might aid speech and language development. Here we asked whether IDS vowels have different articulatory features compared to ADS vowels in two distinct linguistic and socio-cultural contexts: urban English-speaking Canadian mothers, and rural Lenakel- and Southwest Tanna-speaking ni-Vanuatu mothers (n = 57, 20-46 years of age). Replicating prior work, Canadian mothers had more variable vowels in IDS compared to ADS, but also did not show clear register differences for breathiness or hyperarticulation. Vowels spoken by ni-Vanuatu mothers showed very distinct articulatory tendencies, using less variable (and less breathy) IDS vowels. Along with other work showing diversity in IDS phonetics across populations, this paper suggests that any understanding of how IDS might aid speech and language development are best examined through a culturally- and linguistically-specific lens.

Electropalatography (EPG) activities in Japan and the impact of the COVID-19 pandemic on EPG research and therapy: A report of presentations at the 7th EPG Symposium.

BACKGROUND: At the 7th Electropalatography Symposium in Japan, held online on the 24 January 2021, a few speakers were invited to talk about how the COVID-19 pandemic had impacted their research and/or speech therapy that involved the use of electropalatography (EPG) as well as the procedures adopted in order to continue their work in a safe manner. The information on protective measures when using instrumental techniques in speech research and therapy may be useful for colleagues in research and the clinic. AIMS: The primary aims are: (1) to find out whether there are any published recommendations regarding protective measures for using EPG in research and clinic settings; (2) to discuss the impact of the pandemic and the corresponding restrictions and general protective measures directed (or advised) by local government and professional bodies at each stage of EPG work; and (3) to share experiences in using modified procedures for face-to-face EPG therapy sessions and combined EPG teletherapy. In addition, a brief overview of EPG and a summary of EPG research and clinical activities in Japan presented by one of the symposium organizers at the symposium are included. METHODS & PROCEDURES: A review of the literature regarding protective measures recommended for using EPG for speech assessment and treatment or research, supplemented by a discussion of our own experiences. MAIN CONTRIBUTION: The literature review showed that there are no guidelines regarding protective measures for using EPG, but there is some advice regarding speech recording using microphones. Most published articles related to speech and language therapy (SLT) service during COVID-19 are about telepractice or general clinical guidelines for face-to-face speech therapy sessions. The protective measures for using EPG developed based on the general guidelines recommended by local government and professional bodies (e.g., using visors, transparent acrylic board) were described. Using EPG in telepractice was discussed as well. CONCLUSIONS: It has been challenging to continue EPG research and therapy during the pandemic. In order to deal with this crisis, available knowledge regarding infection control and recommendations from local government and professional bodies were applied to design methods and procedures that allowed EPG research and therapy to continue. WHAT THIS PAPER ADDS: What is already known on the subject There are general protective measures recommended by local government and professional bodies regarding speech therapy sessions (e.g., using personal protective equipment (PPE), social distancing), but little is known about the measures for using instrumental techniques in speech research and therapy, particularly EPG. The equipment of each instrumental technique is different, so measures that are appropriate for one may not be suitable for others. Hence, specific recommendations are needed for EPG. What this paper adds to existing knowledge This paper provides pointers to information about recommendations regarding protective measures for speech research and therapy, supplemented with suggestions specific to EPG provided by experienced users based on actual experience. What are the potential or actual clinical implications of this work? In evaluating the impact of the COVID-19 pandemic on EPG research and therapy, an analytical approach was taken to break down the steps involved in carrying out those activities, and the challenges we faced and the possible alternatives for completing the tasks were discussed. A similar approach can be applied to evaluate other aspects of speech therapy service.

The role of f0 shape and phrasal position in Papuan Malay and American English word identification.

The prosodic structure of under-researched languages in the Trade Malay language family is poorly understood. Although boundary marking has been uncontroversially shown as the major prosodic function in these languages, studies on the use of pitch accents to highlight important words in a phrase remain inconclusive. In addition, most knowledge of pitch accents is based on well-researched languages such as the ones from the Western-Germanic language family. This paper reports two word identification experiments comparing Papuan Malay with the pitch accent language American English, in order to investigate the extent to which the demarcating and highlighting function of prosody can be disentangled. To this end, target words were presented to native listeners of both languages and differed with respect to their position in the phrase (medial or final) and the shape of their f0 movement (original or manipulated). Reaction times for the target word identifications revealed overall faster responses for original and final words compared to manipulated and medial ones. The results add to previous findings on the facilitating effect of pitch accents and further improve our prosodic knowledge of underresearched languages.

Vowels in urban and rural Albanian: the case of the Southern Gheg dialect.

Albanian comprises two main dialects, Gheg and Tosk, as well as a Tosk-based standard variety. The study was concerned with the extent to which the vocalic system of Southern Gheg, spoken in the capital city Tirana and surrounding rural area, has been shaped in urban versus rural contexts by extensive contact with Tosk and the standard. Through an apparent-time comparison across two groups of adults and first-grade children, one from Tirana and the other from the nearby village of Bërzhitë, we investigated three vocalic features of Southern Gheg: rounding of /a/, vowel lengthening and monophthongization, all of which were expected to be maintained more in the rural community than in the urban one, and also more by adults than by children. Our results showed that rounding was changing in both locations, monophthongization in the urban setting only, while lengthening was well preserved. In general, the changes found for rounding and monophthongization were more advanced in children than adults. The relative complexity of the features is the main factor explored to account for why some features change faster than others. The reasons for a possible increase in the phonological complexity of Southern Gheg are also discussed.

A Japanese 4-year-old with protracted phonological development: the challenge of coronals.

This study examines the phonology of a Japanese four-year-old with mildly protracted phonological development (PPD) as a contribution to a special crosslinguistic issue presenting individual profiles in PPD within the framework of constraint-based nonlinear phonology. Although the child's word structure and vowels were well-established, certain consonant classes presented challenges. Coronal anterior obstruents often showed posteriorization (backing): dorsal stops replaced coronal stops, and with some exceptions, alveolopalatal affricates replaced anterior fricatives and affricates. The feature [+continuant] was also not yet established: palatal and bilabial fricatives and /h/ were either deleted or replaced with glottal stop; and non-anterior affricates replaced coronal fricatives. If affricates are analyzed as a sequence of [-continuant]-[+continuant], they were possible transitional elements from non-continuants to continuants. The profile culminates with suggestions for intervention based on the nonlinear phonological analysis, consistent with other papers in this special issue.

The Effect of Several Factors on the Patient's Satisfaction with the Complete Dentures and the Correlation with the Adaptation Period.

OBJECTIVE: A great number of patients are completely satisfied with a regular denture, on the other hand, numerous patients are still not satisfied with their denture functions despite proper denture manufacture in relation to prosthetic standards. AIM: To estimate the parameters of satisfaction for patients to improve the health care quality of patients and evaluate the effect of the adaptation period. MATERIALS AND METHODS: A total of 136 patients who participated in this study were patients with complete dentures (CD), after placement of the CD, the patients were asked some questions (about esthetics, phonetics, comfort, quality of fit, and the masticatory efficiency) and the satisfaction of patients was evaluated by using Likert's scale, then recorded four readings, first at the placement visit, second after 1 month, third after 45 days, and last after 2 months. RESULTS: The female patients' satisfaction related to phonetics was about 37.8% at the placement visit, but about 91.2% after 2 months; the male patients' satisfaction related to phonetics was about 44% at the placement visit, then 94.6% after 2 months; the female patients' satisfaction as related to esthetics was about 56.6% at the placement visit, but was about 89.8% after 2 months; the male patients' satisfaction as related to esthetics was about 68% at the placement visit, but about 89.4% after 2 months. CONCLUSION: The satisfaction of the patient with their CD is affected by many factors such as phonetics, esthetics, comfort levels, the quality of fitness of the denture, and the mastication. The differences between gender in satisfaction in all parameters were non-significant, that is, p > 0.001. The adaptation period has an effect on the satisfaction rate of the completely edentulous patient with their CD.

The effects of prematurity and socioeconomic deprivation on early speech perception: A story of two different delays.

There is evidence showing that both maturational and environmental factors can impact on later language development. On the one hand, preterm birth has been found to increase the risk of deficits in the preschool and school years. Preterm children show poorer auditory discrimination, reading difficulties, poor vocabulary, less complex expressive language and lower receptive understanding than their matched controls. On the other hand, socioeconomic status (SES) indicators (i.e., income, education and occupation) have been found to be strongly related to linguistic abilities during the preschool and school years. However, there is very little information about how these factors result in lower linguistic abilities. The present study addresses this issue. To do so, we investigated early speech perception in full and preterm infants from families classed as high or low SES. Seventy-six infants were followed longitudinally at 7.5, 9, 10.5 and 12 months of age. At each test point, three studies explored infants' phonetic, prosodic and phonotactic development respectively. Results showed no significant differences between the phonetic or the phonotactic development of the preterm and the full-term infants. However, a time-lag between preterm and full-term developmental timing for prosody was found. Socioeconomic status did not have a significant effect on prosodic development. Nonetheless, phonetic and phonotactic development was affected by SES, infants from lower SES showed phonetic discrimination of non-native contrast and a preference for high-probability sequences later than their more advantaged peers. Overall these results suggest that different constraints apply to the acquisition of different phonological subcomponents.

Infants' discrimination of consonant contrasts in the presence and absence of talker variability.

To learn speech-sound categories, infants must identify the acoustic dimensions that differentiate categories and selectively attend to them as opposed to irrelevant dimensions. Variability on irrelevant acoustic dimensions can aid formation of robust categories in infants through adults in tasks such as word learning (e.g., Rost and McMurray, 2009) or speech-sound learning (e.g., Lively et al., 1993). At the same time, variability sometimes overwhelms learners, interfering with learning and processing. Two prior studies (Kuhl & Miller, 1982; Jusczyk, Pisoni, & Mullennix, 1992) found that irrelevant variability sometimes impaired early sound discrimination. We asked whether variability would impair or facilitate discrimination for older infants, comparing 7.5-month-old infants' discrimination of an early acquired native contrast, /p/ vs. /b/ (in the word forms /pIm/ vs. /bIm/), in Experiment 1, with an acoustically subtle, non-native contrast, /n/ vs. /ŋ/ (in /nIm/ vs. /ŋIm/), in Experiment 2. Words were spoken by one or four talkers. Infants discriminated the native but not the non-native contrast, and there were no significant effects of talker condition. We discuss implications for theories of phonological learning and avenues for future research.

Lexical analyses of the function and phonology of Papuan Malay word stress.

The existence of word stress in Indonesian languages has been controversial. Recent acoustic analyses of Papuan Malay suggest that this language has word stress, counter to other studies and unlike closely related languages. The current study further investigates Papuan Malay by means of lexical (non-acoustic) analyses of two different aspects of word stress. In particular, this paper reports two distribution analyses of a word corpus, 1) investigating the extent to which stress patterns may help word recognition and 2) exploring the phonological factors that predict the distribution of stress patterns. The facilitating role of stress patterns in word recognition was investigated in a lexical analysis of word embeddings. The results show that Papuan Malay word stress (potentially) helps to disambiguate words. As for stress predictors, a random forest analysis investigated the effect of multiple morpho-phonological factors on stress placement. It was found that the mid vowels /ɛ/ and /ɔ/ play a central role in stress placement, refining the conclusions of previous work that mainly focused on /ɛ/. The current study confirms that non-acoustic research on stress can complement acoustic research in important ways. Crucially, the combined findings on stress in Papuan Malay so far give rise to an integrated perspective to word stress, in which phonetic, phonological and cognitive factors are considered.

Phonetic and phonological vowel reduction in Brazilian Portuguese.

The present study examines the phonetic and phonological status of vowel reduction in Brazilian Portuguese. In order to compare the effects of duration and metrical structure, we tested the influence of duration on the realization of /a/ in five prosodic positions: word-initial pretonic, word-medial pretonic, tonic, word-medial posttonic, and word-final posttonic. The results revealed that, while both phonetic duration and prosodic position had effects on F1 values for /a/, the categorical effect of prosodic position was much stronger and more reliable. In particular, F1 values for /a/ were best predicted by a two-way distinction between posttonic and non-posttonic syllable positions. Correlations between a vowel's duration and its F1 frequency were statistically significant but generally weak in all positions. We argue that these findings suggest that vowel reduction in Brazilian Portuguese primarily reflects phonological patterning rather than phonetic undershoot, although there was also evidence for some amount of undershoot. Brazilian Portuguese can therefore be said to have a mixed system of phonological and phonetic reduction. The present study discusses the results in the context of Brazilian Portuguese metrical organization, sound change, and the relation between phonetics and phonology.

Exploring language dominance through code-switching: intervocalic voiced stop lenition in Afrikaans-Spanish bilinguals.

The present study examines the relationship between the two grammars of bilingual speakers, the linguistic ecologies in which the L1 and L2 become active, and how these topics can be explored in a bilingual community undergoing L1 attrition. Our experiment focused on the production of intervocalic phonemic voiced stops for L1-Afrikaans/L2-Spanish bilinguals in Patagonia, Argentina. While these phonemes undergo systematic intervocalic lenition in Spanish (e.g., /b d É¡/ > [ß ð É£]), they do not in Afrikaans (e.g., /b d/ > [b d]). The bilingual participants in our study produced target Afrikaans and Spanish words in unilingual and code-switched speaking contexts. The results show that: (i) the participants produce separate phonetic categories in Spanish and Afrikaans; (ii) code-switching affects the production of the target sounds asymmetrically, such that L1 Afrikaans influences the production of L2 Spanish sounds but not vice versa; and (iii) this L1-to-L2 influence remains robust despite the instability of the L1 itself. Altogether, our findings speak to the persistence of a bilingual's L1 phonological grammar despite cross-generational L1 attrition.

Prosodic realizations of new, given, and corrective referents in the spontaneous speech of toddlers.

Our motivation was to examine how toddler (2;6) and adult speakers of American English prosodically realize information status categories. The aims were three-fold: 1) to analyze how adults phonologically make information status distinctions; 2) to examine how these same categories are signaled in toddlers' spontaneous speech; and 3) to analyze the three primary acoustic correlates of prosody (F0, intensity, and duration). During a spontaneous speech task designed as an interactive game, a set of target nouns was elicited as one of three types (new, given, corrective). Results show that toddlers primarily used H* across information status categories, with secondary preferences for deaccenting given information and for using L+H* for corrective information. Only duration distinguished information status, and duration, average pitch, and intensity differentiated pitch accent types for both adults and children. Discussion includes how pitch accent selection and input play a role in guiding prosodic realizations of information status.