Purpose: Apraxia of speech (AOS) is a motor speech disorder affecting articulatory planning and speech programming. When AOS is the sole manifestation of neurodegeneration, it is termed primary progressive apraxia of speech (PPAOS). Recent work has shown that there are distinct PPAOS subtypes: phonetic, prosodic, and those that do not clearly…

Purpose: Reduced stress commonly occurs in talkers with Parkinson's disease (PD), whereas excessive and equal stress is frequently associated with dysarthria of talkers with amyotrophic lateral sclerosis (ALS) and multiple sclerosis (MS). This study sought to identify articulatory impairment patterns that underlie these two impaired stress…

Purpose: For individuals with Parkinson's disease (PD), conversational interactions can be challenging. Efforts to improve the success of these interactions have largely fallen on the individual with PD. Successful communication, however, involves contributions from both the individual with PD and their communication partner. The current study…

Purpose: This study aimed to (a) relate temporal patterning of articulation to functional speech outcomes in neurologically healthy and impaired speakers, (b) identify changes in temporal patterning of articulation in neurologically impaired speakers, and (c) evaluate how these changes can be modulated by speaking rate manipulation. Method:…

Purpose: This study investigated whether perceptual ratings of speech parameters were predictive of transcription intelligibility in quiet and in noise for speakers with Parkinson's disease (PD). Method: Ten speakers with PD and five healthy controls read 56 sentences. One group of 60 listeners orthographically transcribed the sentences in quiet,…

Purpose: The aim of this study was to determine how the speech disorder profiles in Down syndrome (DS) relate to reduced intelligibility, atypical overall quality, and impairments in the subsystems of speech production (phonation, articulation, resonance, and prosody). Method: Auditory-perceptual ratings of intelligibility, overall quality, and…

Background: With respect to the clinical criteria for diagnosing "childhood apraxia of speech" (commonly defined as a disorder of speech motor planning and/or programming), research has made important progress in recent years. Three segmental and suprasegmental speech characteristics--error inconsistency, lengthened and disrupted…

Purpose: Auditory perceptual judgments are commonly used to diagnose dysarthria and assess treatment progress. The purpose of the study was to examine the acoustic underpinnings of perceptual speech abnormalities in individuals with Parkinson's disease (PD). Method: Auditory perceptual judgments were obtained from sentences produced by 13 speakers…

Background: Stress production is important for effective communication, but this skill is frequently impaired in people with motor speech disorders. The literature reports successful treatment of these deficits in this population, thus highlighting the therapeutic potential of this area. However, no specific guidance is currently available to…

Purpose: This study explored the speech characteristics of Mandarin-speaking children with cerebral palsy (CP) and typically developing (TD) children to determine (a) how children in the 2 groups may differ in their speech patterns and (b) the variables correlated with speech intelligibility for words and sentences. Method: Data from 6 children…

Purpose: This study compared performance on the Syllable Repetition Task (SRT) by preschoolers with diverse speech and language abilities to identify underlying impairments in speech processes. Method: Three groups of 13 children ages 4 and 5 years with (a) typically developing (TD) speech and language, (b) speech sound disorder (SSD), and (c)…

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: The authors investigated how different variants of clear speech affect segmental and suprasegmental acoustic measures of speech in speakers with Parkinson's disease and a healthy control group. Method: A total of 14 participants with Parkinson's disease and 14 control participants served as speakers. Each speaker produced 18 different…

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: This randomized controlled trial compared the experimental Rapid Syllable Transition (ReST) treatment to the Nuffield Dyspraxia Programme-Third Edition (NDP3; Williams & Stephens, 2004), used widely in clinical practice in Australia and the United Kingdom. Both programs aim to improve speech motor planning/programming for children…