Purpose: This study investigated articulatory patterns for American English /[Voiced alveolar approximant]/ in children with and without a history of residual speech sound disorder (RSSD). It was hypothesized that children without RSSD would favor bunched tongue shapes, similar to American adults reported in previous literature. Based on clinical…

Purpose: The purpose of the current study was to characterize clear speech production for speakers with and without Parkinson disease (PD) using several measures of working vowel space computed from frequently sampled formant trajectories. Method: The 1st 2 formant frequencies were tracked for a reading passage that was produced using habitual and…

Variability in oral reading fluency (ORF), an indicator of foundational reading skills, has been linked to characteristics of texts. Such "text-based variability" in ORF has been traditionally attributed to text complexity, but substantial text-based variability has still been observed after accounting for text complexity. We consider…

Purpose: A critical component to the development of any type of intervention to improve speech production in individuals with Parkinson's disease (PD) is a complete understanding of the speech impairments present at each stage of the disease and how these impairments change with disease progression. The purpose of this longitudinal study was to…

Across languages, certain syllables are systematically preferred to others (e.g., "plaf > ptaf"). Here, we examine whether these preferences arise from motor simulation. In the simulation account, ill-formed syllables (e.g., "ptaf") are disliked because their motor plans are harder to simulate. Four experiments compared…

Purpose: Delayed auditory feedback (DAF) interferes with speech output. DAF causes distorted and disfluent productions and errors in the serial order of produced sounds. Although DAF has been studied extensively, the specific patterns of elicited speech errors are somewhat obscured by relatively small speech samples, differences across studies,…

Down syndrome is a genetic disorder which is represented by a variety of deficits in all linguistic domains including phonology. Previous research, mainly conducted in the English language, has documented phonological deficits in early childhood in Down syndrome. Given the paucity of research in the area of phonology in the Greek language, the aim…

Background: A promising way to obtain vocal economy and efficiency is by semi-occluding the vocal tract while phonating. Current knowledge about the immediate effects of semi-occluded vocal tract (SOVT) phonation on the laryngeal function and configuration is based mainly on computer modelling or excised larynges studies. In in vivo SOVT studies,…

Purpose: Measures of grammatical accuracy are effective measures of children's language skills. However, many measures, such as percent grammatical utterances, were developed for children who speak General American English (GAE) and, therefore, may not be appropriate for students who speak other dialects. This study examines different scoring…

Background: Publicly available speech corpora facilitate reproducible research by providing open-access data for participants who have consented/assented to data sharing among different research teams. Such corpora can also support clinical education, including perceptual training and training in the use of speech analysis tools. Purpose: In this…

Purpose: Rhythm is one procedural mechanism that underlies language and motor skill acquisition and has been implicated in children with childhood apraxia of speech (CAS). The purpose of this study is to investigate manual rhythmic sequencing skills in children with a history of or current CAS (hx/CAS) compared to children with typical development…

This review describes a computational approach for modeling the development of speech motor control in infants. We address the development of two levels of control: articulation of individual speech sounds (defined here as phonemes, syllables, or words for which there is an optimized motor program) and production of sound sequences such as phrases…

Purpose: People who stutter (PWS) have more unstable speech motor systems than people who are typically fluent (PWTF). Here, we used real-time magnetic resonance imaging (MRI) of the vocal tract to assess variability and duration of movements of different articulators in PWS and PWTF during fluent speech production. Method: The vocal tracts of 28…

Purpose: Children progress from making grapheme-phoneme connections to making grapho-syllabic connections before whole-word connections during reading development (Ehri, 2005a). More is known about the development of grapheme--phoneme connections than is known about grapho-syllabic connections. Therefore, we explored the trajectory of syllable use…

Background: Previous studies on language production in normal ageing have primarily focused on distinct dimensions of older adults' spoken language performance, such as fluency and complexity. However, little attention has been paid to the complex, interconnected relations between these dimensions. Additionally, older adults have been treated as a…