Speech and motor speech disorders and intelligibility in adolescents with Down syndrome

Abstract

The goal of this research was to assess the support for motor speech disorders as explanatory constructs to guide research and treatment of reduced intelligibility in persons with Down syndrome (DS). Participants were the 45 adolescents with DS in the prior paper who were classified into five mutually-exclusive motor speech classifications using the Speech Disorders Classification System. An ordinal index classified participants’ percentage of intelligible words in conversation as High (≥ 85%), Moderate (80% – 84.9%), or Low (< 80%). Statistical analyses tested for significant differences in intelligibility status associated with demographic, intelligence, and language variables, and intelligibility status associated with motor speech classifications and speech, prosody, and voice variables. For the 10 participants who met criteria for concurrent Childhood Dysarthria and Childhood Apraxia of Speech at assessment, 80% had reduced (Moderate or Low) intelligibility and 20% had High intelligibility (significant effect size: 0.644). Proportionally more of the 32 participants who met criteria for either dysarthria or apraxia had reduced intelligibility (significant effect size: 0.318). Low intelligibility was significantly associated with across-the-board reductions in phonemic and phonetic accuracy and with inappropriate prosody and voice. Findings are interpreted as support for motor speech disorders in adolescents with DS as explanatory constructs for their reduced intelligibility. Pending cross-validation of findings in diverse samples of persons with DS, studies are needed to assess the efficacy of motor speech classification status to guide selection of treatment methods and intelligibility targets.

Estimates of the prevalence of speech and motor speech disorders in adolescents with Down syndrome

“…Notably for the present context, some of the current participants had lower than typical speech scores on the Percentage of Consonants Correct (59.3%−93.3%), Percentage of Vowels Correct (77.7%−96.7%), and Percentage of Intelligible Words (50.1%−99%). The reduced intelligibility findings in Table 2 are the focus of research reported with the present participants in Wilson, Abbeduto, Camarata, and Shriberg (2019).…”

Estimates of the prevalence of speech and motor speech disorders in persons with complex neurodevelopmental disorders

“…As indicated in Table 3, ataxic dysarthria is associated with deficits in cerebellar processes (e.g., Kent & Vorperian, 2013; Nadel, 2003), with implications for genomic and speech treatment research for persons with DS (cf. Wilson, Abbeduto, Camarata, & Shriberg, 2019a, 2019b).…”

“…The Simons VIP Consortium (2012).22q11.2 Deletion Syndrome22q1817Inclusionary criteria included: (a) diagnosis of 22q11.2 deletion syndrome by Fluorescence In Situ Hybridization (FISH) testing or microarray, (b) 6–18 years of age, (c) English as the participant’s primary language, and (d) no history of permanent bilateral hearing loss.Baylis and Shriberg (2018)Autism Spectrum DisorderASD4242Inclusionary criteria included: (a) a previous diagnosis of autism, PDD-NOS, ASD, or Asperger syndrome from a qualified clinician; (b) full scale IQ ≥ 70; (c) mean length of utterance of at least 3.0, based on transcription of a 3–5 min conversational sample; (d) > 70% of words intelligible in the language sample; and (e) normal hearing and vision (or corrected with glasses) on standard screening. Exclusionary criteria included known craniofacial or neurological impairment or bilingual background.Shriberg, Paul, Black, and van Santen (2011)Down syndromeDS5045Three samples of participants: (1) 29 participants, 10–18 years of age with a confirmed diagnosis of Trisomy 21 and no diagnosis of autism spectrum disorders; (2) 17 participants, 8–18 years of age, with a confirmed diagnosis of Trisomy 21 and no diagnosis of autism spectrum disorders; (3) 4 male participants, ages 13–20 years, with a confirmed diagnosis of Trisomy 21.Wilson, Abbeduto, Camarata, and Shriberg (2019a; 2019b); Camarata, Yoder, and Camarata (2006);Davis, Camarata, and Camarata (2016)fragile X syndromeFXS3028Males ranging in age from 11–22 yrs.Inclusionary criteria: (a) DNA or cytogenetic confirmation of the syndrome; (b) speech as the primary means of communication; (c) no more than a mild hearing loss per Chapman, Schwartz, and Kay-Raining Bird (1991) criterion; (d) ability to complete all tests; (e) nonverbal IQs <70; (f) passed screening and follow-up psychologist assessment for ASD.Abbeduto, Murphy, Cawthon, Richmond, Weissman, Karadottir, and O’Brien (2003);Abbeduto, Murphy, Kover, Giles, Karadottir, Amman, Bruno, Kim, Schroeder, Anderson, and Nollin (2008); Keller-Bell and Abbeduto (2007)Galactosemia…”

Análise da intervenção fonoaudiológica em apraxia de fala na síndrome de Down: um estudo de caso

“…Estudo realizado com 45 adolescentes com SD mostrou associação entre baixa inteligibilidade de fala e redução na precisão fonêmica e fonética, bem como inadequação de prosódia e voz. Os resultados apontaram que a disartria e a apraxia apresentaram um impacto significativo na redução da inteligibilidade de fala 18 .…”