Purpose: In this study, we examined the utility of vowel intelligibility testing for assessing the impact of dysarthria on speech characteristics in people with amyotrophic lateral sclerosis (ALS). We tested the sensitivity and specificity of overall vowel identification, as well as that of vowel-specific identification, to dysarthria presence and…

This study examines the effects of task complexity on second language (L2) pronunciation accuracy and global pronunciation measures in pronunciation-unfocused tasks and assesses the relationship between acoustic and listener-based pronunciation measures. Eighty-two Catalan/Spanish learners of English performed simple and complex versions of a…

Background: Previous research has found that high-frequency energy of speech signals decreased while wearing face masks. However, no study has examined the specific spectral characteristics of fricative consonants and vowels and the perception of clarity of speech in mask wearing. Aims: To investigate acoustic-phonetic characteristics of fricative…

A growing body of research finds that neurotypical autistic traits are predictive of speech perception and language comprehension patterns, but considerably less is known about the influence of these traits on speech production. In this brief report, we present an analysis of vowel productions from 74 American English speakers who participated in…

Although intelligibility is a core concept in second language (L2) speech assessment and teaching research, the vast majority of previous work relies on audio-only stimuli. The current study set out to examine how linguistic and visual information jointly interact to determine the degree of speech intelligibility. Both first language (L1) and L2…

Intelligibility is a critically important aspect for effective oral communication. This study explored salient (important) pronunciation errors and their relative roles in the intelligibility of nonnative speech based on listener judgments. Speech samples, collected from speakers with a Turkish as a native language (L1) background, were presented…

Background: Developmental dysarthria is a motor speech impairment commonly characterized by varying levels of reduced speech intelligibility. The relationship between intelligibility deficits and acoustic vowel space among these individuals has long been noted in the literature, with evidence of vowel centralization (e.g., in English and…

Purpose: The purpose of this study was to characterize the acoustic profile and to evaluate the intelligibility of vowel productions in prelingually deafened, Mandarin-speaking children with cochlear implants (CIs). Method: Twenty-five children with CIs and 20 age-matched children with normal hearing (NH) were recorded producing a list of Mandarin…

Purpose: This study examined the acoustic properties of Taiwanese (Southern Min) lexical tones produced in esophageal speech (ES) and pneumatic artificial laryngeal speech (PAL), including onset fundamental frequency (F0), slope of F0 contour, duration, and amplitude (intensity) of the vowel portion of syllables carrying seven Taiwanese tones.…

Purpose: It is generally accepted that adults use visual cues to improve speech intelligibility in noisy environments, but findings regarding visual speech benefit in children are mixed. We explored factors that contribute to audiovisual (AV) gain in young children's speech understanding. We examined whether there is an AV benefit to…

This study investigates how second language (L2) listeners' perception is affected by two factors: the listeners' experience with the target dialect -- North American English (NAE) vs. Standard Southern British English (SSBE) -- and talkers' language background: native vs. non-native talkers; i.e. interlanguage speech intelligibility benefit…

Purpose: In this study, the authors proposed and tested a preliminary speech and language classification system for children with cerebral palsy. Method: Speech and language assessment data were collected in a laboratory setting from 34 children with cerebral palsy (CP; 18 male, 16 female) with a mean age of 54 months (SD = 1.8). Measures of…

This study investigated the impact of a well-defined behavioral dysarthria treatment on acoustic and perceptual measures of speech in four adults with dysarthria secondary to stroke. A single-subject A-B-A experimental design was used to measure the effects of the Lee Silverman Voice Treatment (LSVT[R]LOUD) on the speech of individual…

Purpose: This study examined the effect of alphabet supplementation (AS) on temporal and spectral features of speech production in individuals with cerebral palsy and dysarthria. Method: Twelve speakers with dysarthria contributed speech samples using habitual speech and while using AS. One hundred twenty listeners orthographically transcribed…

This study examined the acoustic characteristics of vowels produced by speakers with partial glossectomy. Acoustic variables investigated included first formant (F1) frequency, second formant (F2) frequency, F1 range, F2 range and vowel space area. Data from the speakers with partial glossectomy were compared with age- and gender-matched controls.…