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…

This paper addresses how input variability in the adult phonological system is mastered in the output of young children in Akan, a Kwa language spoken in Ghana, involving variability between labio-palatalized consonants and front rounded vowels. The high-frequency variant involves a complex consonant which is expected to be mastered late, while…

Purpose: We compare teens' and adults' imitation of sentences with shortened and lengthened voice onset time (VOT), in order to test whether purported age-based advantages in phonetic acquisition may be due to differences in imitative ability. Method: Teens (M[subscript age] = 13, n = 39) and adults (n = 31) completed an explicit imitation and…

Purpose: The purpose of this study is to test whether age-related differences in grammatical word production are due to differences in how children and adults chunk speech for output or to immature articulatory timing control in children. Method: Two groups of 12 children, 5 and 8 years old, and 1 group of 12 adults produced sentences with…

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…

Purpose: This study reports on a cross-sectional investigation of lingual coarticulation in 57 typically developing German children (4 cohorts from 3.5 to 7 years of age) as compared with 12 adults. It examines whether the organization of lingual gestures for intrasyllabic coarticulation differs as a function of age and consonantal context.…

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…

This longitudinal study assessed three acoustic components of maternal infant-directed speech (IDS) -- pitch, affect, and vowel hyperarticulation -- in relation to infants' age and their expressive vocabulary size. These three individual components were measured in IDS addressed to infants at 7, 9, 11, 15, and 19 months (N = 18). All three…

Purpose: This study examines the temporal organization of vocalic anticipation in German children from 3 to 7 years of age and adults. The main objective was to test for nonlinear processes in vocalic anticipation, which may result from the interaction between lingual gestural goals for individual vowels and those for their neighbors over time.…

Purpose: The goal of this study was to better understand how and when onset /l/ ("leap") and coda /l/ ("peel") are acquired by children by examining both the articulations involved and adults' perceptions of the produced segments. Method: Twenty-five typically developing Australian English-speaking children aged 3;0…

Seeing articulatory gestures enhances speech perception. Perception of auditory speech can even be changed by incongruent visual gestures, which is known as the McGurk effect (e.g., dubbing a voice saying /mi/ onto a face articulating /ni/, observers often hear /ni/). In children, the McGurk effect is weaker than in adults, but no previous…

Purpose: Although dysarthria affects the large majority of individuals with cerebral palsy (CP) and can substantially complicate everyday communication, previous research has provided an incomplete picture of its clinical features. We aimed to comprehensively describe characteristics of dysarthria in adults with CP and to elucidate the impact of…

Purpose: In this study, the authors compared coarticulation and lingual kinematics in preadolescents and adults in order to establish whether preadolescents had a greater degree of random variability in tongue posture and whether their patterns of lingual coarticulation differed from those of adults. Method: High-speed ultrasound tongue contour…

Purpose: To improve our understanding about the underlying factors of aging-related speaking rate decline, the authors sought to determine if lip and jaw speeds are physiologically constrained in older adults. Method: Thirty-six female--10 young adults (ages 22-27 years), 9 middle-aged adults (ages 45-55 years), 10 young-old adults (65-74 years),…