Purpose: To assess autonomic arousal associated with speech and nonspeech tasks in school-age children and young adults. Method: Measures of autonomic arousal (electrodermal level, electrodermal response amplitude, blood pulse volume, and heart rate) were recorded prior to, during, and after the performance of speech and nonspeech tasks by twenty…

Purpose: The study was aimed at characterizing age-related changes in speech motor performance on a nonword repetition task as a function of practice and nonword length and complexity. Method: Nonword repetition accuracy, lip aperture coordination, and nonword production durations were assessed on 2 consecutive days for 16 young and 16 elderly…

Purpose: In this study, the authors determined whether basic patterns of muscle activation for speech were similar in preschool children who stutter and in their fluent peers. Method: Right and left lower lip muscle activity were recorded during conversational speech and sentence repetition in 64 preschool children diagnosed as stuttering (CWS)…

Purpose: To investigate the potential effects of increased sentence length and syntactic complexity on the speech motor control of children who stutter (CWS). Method: Participants repeated sentences of varied length and syntactic complexity. Kinematic measures of articulatory coordination variability and movement duration during perceptually…

Purpose: To investigate the effects of increased syntactic complexity and utterance length demands on speech production and comprehension in individuals with Parkinson's disease (PD) using behavioral and physiological measures. Method: Speech response latency, interarticulatory coordinative consistency, accuracy of speech production, and response…

Purpose: To determine whether young children who stutter have a basic motor timing and/or a coordination deficit. Method: Between-hands coordination and variability of rhythmic motor timing were assessed in 17 children who stutter (4-6 years of age) and 13 age-matched controls. Children clapped in rhythm with a metronome with a 600-ms interbeat…

Purpose: To examine how age of immersion and proficiency in a 2nd language influence speech movement variability and speaking rate in both a 1st language and a 2nd language. Method: A group of 21 Bengali-English bilingual speakers participated. Lip and jaw movements were recorded. For all 21 speakers, lip movement variability was assessed based on…

Purpose: To assess, in children and adults, the breadth of coarticulatory movements associated with a single rounded vowel. Method: Upper and lower lip movements were recorded from 8 young adults and 8 children (aged 4-5 years). A single rounded versus unrounded vowel was embedded in the medial position of pairs of 7-word/7-syllable sentences.…

Purpose: The authors examined the effects of utterance length and linguistic complexity on speech movement consistency for 210 participants between the ages of 5 and 22 years. Variability and durational analyses were conducted to (a) determine a more complete picture of the developmental course of earlier observations of the effects of linguistic…

Event-related brain potentials (ERPs), judgment accuracy, and reaction times (RTs) were obtained for 11 adults who stutter and 11 normally fluent speakers as they performed a rhyme judgment task of visually presented word pairs. Half of the word pairs (i.e., prime and target) were phonologically and orthographically congruent across words. That…

This study compared articulatory movements of 30 adolescents (12-16 years) and 30 young adults. Trajectory variability, especially lip trajectories, was higher for the adolescents. Adolescents also had significantly longer movement durations, lower velocities, smaller displacements, and greater variability on these measures than young adults. No…

This study examined possible influences of utterance length and complexity on speech motor performance with eight 5-year-old children and eight young adults using the spatiotemporal index (STI), a measure of stability of lip movement over phrase repetitions. The STI was significantly higher in the complex sentence condition and for the younger…

This study examined whether stuttering speakers (N=10) differed from fluent speakers in relations between the neural control systems for speech and life support. It concluded that in some stuttering speakers the relations between respiratory controllers are atypical, but that high participation by the high frequency oscillation-producing circuitry…

A study of 16 children (ages 4 and 7 years) and 8 young adults used an "Optotrak" system to study patterning and stability of speech movements in developing speech motor systems. Results indicate that nonlinear and nonuniform changes occur in components of the speech motor system during development. (Author/CR)