UNASSIGNED: This study aims at investigating the phonological development of the six guttural consonants of Jordanian Arabic, /χ/, /ʁ/, /ħ/, /ʕ/, /ʔ/, and /h/.
UNASSIGNED: An articulation test is designed to involve two tasks: picture naming and repetition. The test includes 54 words for picture naming and 18 words for repetition, representing all possible positions of the targeted guttural sounds. Samples are collected from 40 typically developing Ammani-Jordanian Arabic-speaking monolingual children, living in Amman, Jordan. Respondents are equally divided into eight age-related trajectories: 2-2;6, 2;6-3, 3-3;6, 3;6-4, 4-4;6, 4;6-5, 5-5;6, and 5;6-6 (years;months). No child with a history of hearing, speech, or vision disorders is included. The data are analyzed using production accuracy, where the three developmental trajectories of production (customary, acquisition, and mastery) are determined for each guttural, and error analysis, addressed based on perceptual judgments, providing details of every mispronounced or deleted guttural.
UNASSIGNED: The results show that /χ/, /ħ/, /ʕ/, and /ʔ/ are acquired before the age of 6 years, while /ʁ/ and /h/ are still not acquired by this age. Respondents use relatively variant alternatives for the mispronounced cognates, including guttural, nonguttural sounds, and vowel substitution. The /ʁ/ is the guttural with the highest number of alternatives, while /ʔ/ gets the least. The analysis also reveals patterns of guttural deletion, with variations across different guttural sounds and positions. Despite errors/deviations made, respondents score accuracy percentages that gradually increase in correlation with age. The guttural /ʁ/ starts with the lowest accuracy percentages, while /ʔ/ and /ħ/ start with the highest.
UNASSIGNED: These findings illuminate on the developmental trajectory of guttural acquisition and enrich our understanding of children\'s evolving perception and production abilities. They offer valuable insights into the patterns of guttural sound production in Jordanian Arabic-speaking children, laying the groundwork for further research and the development of targeted assessment and intervention strategies to support phonological development in this population.

This study examines the lateral biases in tongue movements during speech production. It builds on previous research on asymmetry in various aspects of human biology and behavior, focusing on the tongue\'s asymmetric behavior during speech. The findings reveal that speakers have a pronounced preference toward one side of the tongue during lateral releases with a majority displaying the left-side bias. This lateral bias in tongue speech movements is referred to as tonguedness. This research contributes to our understanding of the articulatory mechanisms involved in tongue movements and underscores the importance of considering lateral biases in speech production research.

Oral diadochokinesis is a useful task in assessment of speech motor function in the context of neurological disease. Remote collection of speech tasks provides a convenient alternative to in-clinic visits, but scoring these assessments can be a laborious process for clinicians. This work describes Wav2DDK, an automated algorithm for estimating the diadochokinetic (DDK) rate on remotely collected audio from healthy participants and participants with amyotrophic lateral sclerosis (ALS).
Wav2DDK was developed using a corpus of 970 DDK assessments from healthy and ALS speakers where ground truth DDK rates were provided manually by trained annotators. The clinical utility of the algorithm was demonstrated on a corpus of 7,919 assessments collected longitudinally from 26 healthy controls and 82 ALS speakers. Corpora were collected via the participants\' own mobile device, and instructions for speech elicitation were provided via a mobile app. DDK rate was estimated by parsing the character transcript from a deep neural network transformer acoustic model trained on healthy and ALS speech.
Algorithm estimated DDK rates are highly accurate, achieving .98 correlation with manual annotation, and an average error of only 0.071 syllables per second. The rate exactly matched ground truth for 83% of files and was within 0.5 syllables per second for 95% of files. Estimated rates achieve a high test-retest reliability (r = .95) and show good correlation with the revised ALS functional rating scale speech subscore (r = .67).
We demonstrate a system for automated DDK estimation that increases efficiency of calculation beyond manual annotation. Thorough analytical and clinical validation demonstrates that the algorithm is not only highly accurate, but also provides a convenient, clinically relevant metric for tracking longitudinal decline in ALS, serving to promote participation and diversity of participants in clinical research.
https://doi.org/10.23641/asha.23787033.

AIMS: To investigate the developmental trajectory of the rate and perceptual assessment of oral diadochokinesis (DDK) in typically developing children compared with adults. Also to examine the characteristics of DDK productions in children with speech sound disorders (SSD) and the relationship between DDK production and percentage of consonants correct (PCC).
Participants were 316 typically developing children and 90 children with SSD from 3 to 9 years old, as well as 20 adults with normal speech. The mono-, bi- and trisyllabic nonsense strings containing Korean tense consonants and the vowel [a] were used for DDK tasks. The number of iterations per s was measured as the DDK rate for each stimulus. The perceptual assessment of DDK productions was also performed for regularity, accuracy and rate.
The DDK rates increased throughout childhood, but the oldest children, 9-year-olds in the current study, did not achieve adult-like rates for all mono- and trisyllabic strings. Children with SSD also did not show significant differences from typically developing children when the DDK productions were analysed using only accurate tokens. The PCC of children with SSD showed higher correlations with regularity, accuracy and rate of perceptual ratings than the timed DDK rate.
This study highlighted the fact that the comprehensive evaluation of DDK productions may provide even more useful information about children\'s oral motor skills.
What is already known on the subject Rates of DDK reflect the motor skills of the articulatory systems independently of phonological skills; therefore, the tasks are widely used in the diagnostic evaluations of speech disorders in both children and adult populations. However, a substantial number of studies have questioned the validity and usefulness of DDK rates for evaluating speech abilities. Also, the literature suggested that the measure of DDK rate alone does not provide a clear and useful indication of children\'s oral motor skills. DDK tasks should be analysed in terms of accuracy and consistency as well as rate. What this paper adds to the existing knowledge The literature reporting normative DDK performance has mainly been based on English speakers. As different consonants have different temporal characteristics, the linguistic and segmental features of DDK tasks can impact the DDK rate. This study established a norm for DDK rate for Korean-speaking children and investigated the developmental trajectory of DDK performance in typically developing children compared with adults. This study suggested that the comprehensive evaluation of DDK productions may provide even more useful information about children\'s oral motor skills by examining the characteristics of DDK productions in children with SSD. What are the potential or actual clinical implications of this work? This study provided normative data of young Korean-speaking children aged 3-9 years. Normative data in children under 5 years of age are valuable given that the majority of children referred for speech difficulty assessments are between 3 and 5 years of age, but only a few studies have provided the normative data in young children. This study showed that many children could not complete DDK tasks correctly and provided additional support for the notion that other aspects of DDK performance, including accuracy and regularity, may yield more useful diagnostic indications than timed DDK rates alone.

A phenomenon called \"repetition reduction\" can increase articulation rate in adults by facilitating phonetic and motor processes, which indicates flexibility in the control of articulation rate. Young children, who speak much slower, may not have the same speech motor flexibility resulting in the absence of the repetition reduction effect. In this study, we tested whether spontaneous repetitions of young children are produced with a faster articulation rate than their original utterances. Twelve monolingual English-speaking children were observed at four time points between 2;0 and 3;0 years of age. A significant increase in articulation rate and syllable count was found using multilevel models for all utterances over the 1-year period. At each time point, however, the repeated utterances were produced significantly faster than the original utterances even though the content and syllable count differed minimally. Our findings conform to the pattern of adult studies suggesting that a \"naturistic\" form of repetition reduction is already present in the speech of children at 2;0 years. Although certain aspects of speech motor control are undergoing rapid development, existing motor capability at 2;0 already supports flexible changes in articulation rate including repetition reduction.

As a class, fricatives are more \"resistant\" to consonant-vowel coarticulation than other English sounds. This study investigates the relative coarticulatory resistance of /θ, s, ʃ/ in child and adult speech to better understand the acquisition of individuated speech sounds.
Ten 5-year-old children, seven 8-year-old children, and nine college-age adults produced [əFV] sequences in carrier phrases, where F was /θ/, /s/, or /ʃ/ and V was /æ/, /i/, or /u/. In Experiment 1, coarticulation was perceptually indexed: 65 adults predicted the target stressed vowel based on forward-gated audiovisual speech samples for a subset of four speakers from each age group. In Experiment 2, dynamic spectral measures of the /əFV/ sequences were analyzed using smoothing spline analysis of variance to again test for vowel effects on fricative articulation across age groups.
The perceptual results indicated that fricatives blocked vowel-vowel coarticulation across speaker age groups. Contrary to expectation, vowels were most accurately predicted when F was /s/ and not when it was /ʃ/ or /θ/ across age groups. Acoustic results indicated the expected biomechanically motivated /ʃ/ > /s/ > /θ/ coarticulatory resistance hierarchy in adults\' speech. By contrast, /ʃ/ > /s/ were similarly influenced by context in 8-year-olds\' speech, and the results from 5-year-olds\' speech suggested an influence of order of acquisition in that /θ/ was surprisingly resistant to coarticulation.
The study results are taken to suggest that a temporal constraint on fricative articulation interacts with biomechanical constraints during development to influence patterns of coarticulation in school-age children\'s speech.

Anticipatory coarticulation is an indispensable feature of speech dynamics contributing to spoken language fluency. Research has shown that children speak with greater degrees of vowel anticipatory coarticulation than adults - that is, greater vocalic influence on previous segments. The present study examined how developmental differences in anticipatory coarticulation transfer to the perceptual domain.Using a gating paradigm, we tested 29 seven-year-olds and 93 German adult listeners with sequences produced by child and adult speakers, hence corresponding to low versus high vocalic anticipatory coarticulation degrees. First, children predicted vowel targets less successfully than adults. Second, greater perceptual accuracy was found for low compared to highly coarticulated speech. We propose that variations in coarticulation degrees reflect perceptually important differences in information dynamics and that listeners are more sensitive to fast changes in information than to a large amount of vocalic information spread across long segmental spans.

BACKGROUND: Diadochokinetic rates tasks are frequently used for the assessment of diadochokinesia (DKK) in young and elderly adults. However, there is scarce research on healthy elderly adults over 65 years old, and little is known about the effect of different types of stimuli (non-words/real words) in this specific population. Furthermore, the current research supports significant language variations, highlighting the need for language-specific norms.
OBJECTIVE: To investigate the effect of age, gender and type of stimuli (non-words versus real words) in DDK rates in healthy elderly adults of over 65 years of age, and to provide normative data for the Greek language.
METHODS: The participants were 791 healthy monolingual Greek-speaking adults (531 adults, aged 20-39 years; 157 participants aged 65-74 years; and 103 participants aged over 75 years). All participants were monolingual speakers of Greek and had normal hearing acuity, which allowed them to understand and follow instructions. Participants with a medical condition, which would affect DDK rates\' performance, were excluded from the study. The time-by-count method was used, and all participants had to repeat as accurately and fast as possible: (1) four disyllabic non-words (/\'gaba/, /\'taka/, /\'kata/, /\'baga/); (2) four disyllabic real words (/\'kapa/, /\'tapa/, /ka\'la/, /\'paka/); and (3) two trisyllabic non-words (/\'pataka/, /\'badaga/). All responses were recorded and the speech samples that did not include at least 5 s of correct repetitions were excluded from the analysis.
RESULTS: Age affected DDK rates significantly, with older adults achieving slower DDK rates for all speech stimuli (non-words/real words). Gender did not have an effect on the performance of DDK rates. The type of speech stimuli affected DDK rates significantly for all age groups. Analytically, trisyllabic non-word stimuli were articulated more slowly than disyllabic non-word stimuli, and real words were produced faster than non-words. A linear regression analysis revealed that only the repetition of non-words predicted 68.4% of the performance on the repetition of trisyllabic non-words.
CONCLUSIONS: The above results complement prior research, which supports that real word stimuli yield faster performance than non-word stimuli. Clinicians should keep in mind that age, language and type of stimuli (non-words/real words) affect significantly the performance of DDK rates, as well as the fact that different types of stimuli tap distinct underlying levels of speech. The current research highlights the need for language-specific norms for different populations.
CONCLUSIONS: What is already known on the subject DDK rates are significantly affected by the types of stimuli and language used. Moreover, the normal ageing process decreases performance in terms of DDK rates, but scarce evidence exists for healthy elderly adults over 65 years old. What this paper adds to existing knowledge Most studies have examined DDK rates in healthy elderly people with restricted samples and using non-word stimuli. The current study administered different types of stimuli (non-words/words) in a large sample of healthy elderly participants. This is also the first study to attempt to provide DDK normative data for this population in the Greek language. What are the potential or actual clinical implications of this work? The results of this study strongly suggest that clinicians should bear in mind the significant impact age and language have on performance in terms of DDK rates, especially when normative data are not available for a certain language or age group. Furthermore, non-word and real-word stimuli cannot be used interchangeably since they tap into distinct underlying levels of speech, thus providing clinicians with useful information about the level of breakdown and the proper treatment plan.

Extensive research has found that the duration of a pause is influenced by the length of an upcoming utterance, suggesting that speakers plan the upcoming utterance during this time. Research has more recently begun to examine articulation during pauses. A specific configuration of the vocal tract during acoustic pauses, termed pause posture (PP), has been identified in Greek and American English. However, the cognitive function giving rise to PPs is not well understood. The present study examines whether PPs are related to speech planning processes, such that they contribute additional planning time for an upcoming utterance. In an articulatory magnetometer study, the hypothesis is tested that an increase in upcoming utterance length leads to more frequent PP occurrence and that PPs are longer in pauses that precede longer phrases. The results indicate that PPs are associated with planning time for longer utterances but that they are associated with a relatively fixed scope of planning for upcoming speech. To further examine the relationship between articulation and speech planning, an additional hypothesis examines whether the first part of the pause predominantly serves to mark prosodic boundaries while the second part serves speech planning purposes. This hypothesis is not supported by the results.

OBJECTIVE: The relationship between ankyloglossia and speech is controversial. The objective of this study was to determine the effect of tongue-tie release on speech articulation and intelligibility.
METHODS: A prospective cohort study was conducted. Pediatric patients (>2 years of age) being referred for speech concerns due to ankyloglossia were assessed by a pediatric otolaryngologist, and speech articulation was formally assessed by a speech language pathologist using the Goldman-Fristoe Test of Articulation 2 (GFTA-2). Patients then underwent a tongue-tie release procedure in clinic. After 1 month, speech articulation was reassessed with GFTA-2. Audio-recordings of sessions were evaluated by independent reviewers to assess speech intelligibility before and after tongue-tie release.
RESULTS: Twenty-five participants were included (mean age 3.7 years; 20 boys). The most common speech errors identified were phonological substitutions (80%) and gliding errors (56%). Seven children (28%) had abnormal lingual-alveolar and interdental sounds. Most speech sound errors (87.9%) were age/developmentally appropriate. GFTA-2 standard scores before and after tongue-tie release were 85.61 (SD 9.75) and 87.54 (SD 10.21), respectively, (P=.5). Mean intelligibility scores before and after tongue-tie release were 3.15 (SD .22) and 3.21 (SD .31), respectively, (P=.43).
CONCLUSIONS: The majority of children being referred for speech concerns thought to be due to ankyloglossia had age-appropriate speech errors at presentation. Ankyloglossia was not associated with isolated tongue mobility related speech articulation errors in a consistent manner, and there was no benefit of tongue-tie release in improving speech articulation or intelligibility.