Purpose: We proposed and tested a causal instantiation of the World Health Organization's International Classification of Functioning, Disability and Health (ICF) framework, linking acoustics, intelligibility, and communicative participation in the context of dysarthria. Method: Speech samples and communicative participation scores were collected…

Purpose: As a class, fricatives are more "resistant" to consonant-vowel coarticulation than other English sounds. This study investigates the relative coarticulatory resistance of /[voiceless dental fricative], s, [voiceless palato-alveolar fricative]/ in child and adult speech to better understand the acquisition of individuated speech…

The study shows that there are two distinct lateral phonemes in Turkish with a minimal pair example. 20 male native speakers of Turkish, aged 20-26, were asked to read six short phrases and a minimal pair which contained laterals. The spectrograms were examined by PRAAT to determine whether it is possible to identify the laterals with regard to…

Purpose: Phonetic variation due to domain initial strengthening was investigated with respect to the acoustic and articulatory distinctiveness of vowels within a subset of the French oral vowel system /i, e, ?, a, o, u/, organized along 4 degrees of height for the front vowels and 2 degrees of backness at the close and midclose height levels.…

The purpose of this exploratory study was to examine speech characteristics in individuals with Parkinson's disease (PD) before and after participation in an 11-week choral singing intervention. Speech characteristics were analyzed using an acoustic measure of vowel space area (VSA) and a standardized speech intelligibility metric. Participants…

Purpose: Individuals with primary progressive apraxia of speech (PPAOS) have apraxia of speech (AOS) in which disruptions in articulation or prosody predominate the speech pattern, referred to, respectively, as phonetic or prosodic subtypes. Many develop aphasia and/or dysarthria. Past research has demonstrated that simple temporal acoustic…

Purpose: Most acoustic and articulatory studies on /l/ have focused on either duration, formant frequencies, or tongue shape during the constriction interval. Only a limited set of data exists for the transition characteristics of /l/ to and from surrounding vowels. The aim of this study was to examine second formant (F2) transition…

Purpose: This study investigated the impact of lexical characteristics on the intelligibility of speakers with Parkinson's disease (PD). Intelligibility was compared for listening in a quiet versus a noisy environment. Method: A total of 192 young listeners participated in the study, with 96 listeners listening in quiet and 96 listening in noise…

Purpose: Liquids are among the last sounds to be acquired by English-speaking children. The current study considers their acquisition from an articulatory timing perspective by investigating anticipatory posturing for /l/ versus /[voiced alveolar approximant]/ in child and adult speech. Method: In Experiment 1, twelve 5-year-old, twelve…

Compared to low-variability training, high-variability training leads to better learning outcomes and supports generalization of learning. However, it is unclear whether the learning advantage is driven by multiple talkers or by enhanced acoustic variability across target sounds. The current study addressed this issue in nonnative production…

Purpose: The aim of this study was to provide a systematic review of the aspects of verbal communication contributing to listener perceptions of speaker gender with a view to providing clinicians with guidance for the selection of the training goals when working with transsexual individuals. Method: Preferred reporting items for systematic review…

This study investigated the role of cross-linguistic similarity in the acquisition of Russian initial stop contrasts by Chinese learners, addressing two specific research questions: (1) How similar are Russian voiced stops to Mandarin stops for Chinese learners?; and (2) How can the speech learning model (SLM) be applied to account for the…

Purpose: This study aimed to identify predictors of response to treatment for residual speech sound disorder (RSSD) affecting English rhotics. Progress was tracked during an initial phase of traditional motor-based treatment and a longer phase of treatment incorporating ultrasound biofeedback. Based on previous literature, we focused on baseline…

This dissertation investigates language-specific acoustic and aerodynamic phenomena in language contact situations. Whereas most work on second language and bilingual phonology has focused on individual consonants and vowels, this project examines patterns of coarticulation in the two languages of Spanish-English and French-English bilingual…

The study analysed spectral and tongue shape dynamics of voiceless alveolar and postalveolar fricatives produced by ten children learning Scottish English. Synchronised ultrasound tongue imaging data and acoustic data were used to characterise children's productions of the phonemic contrast. Six children had consistently accurate productions of…