An exploratory study of the influence of load and practice on segmental and articulatory variability in children with speech sound disorders

Abstract

This exploratory treatment study used phonetic transcription and speech kinematics to examine changes in segmental and articulatory variability. Nine children, ages 4- to 8-years-old, served as participants, including two with childhood apraxia of speech (CAS), five with speech sound disorder (SSD), and two who were typically developing (TD). Children practised producing agent + action phrases in an imitation task (low linguistic load) and a retrieval task (high linguistic load) over five sessions. In the imitation task in session one, both participants with CAS showed high degrees of segmental and articulatory variability. After five sessions, imitation practice resulted in increased articulatory variability for five participants. Retrieval practice resulted in decreased articulatory variability in three participants with SSD. These results suggest that short-term speech production practice in rote imitation disrupts articulatory control in children with and without CAS. In contrast, tasks that require linguistic processing may scaffold learning for children with SSD but not CAS.

Speech articulation in children with Williams syndrome or 7q11.23 duplication syndrome.

“…However, articulatory variability does not equate with articulatory inaccuracy (Fowler & Saltzman, 1993;Kelso, Vatikiotis-Bateson, Saltzman, & Kay, 1985;Smith & Goffman, 1998;Vuolo & Goffman, 2017). Researchers have shown that when speaking in short phrases, the spatiotemporal characteristics of children's speech are both wider and slower than adult speech (Smith & Zelaznik, 2004;Walsh & Smith, 2002) and children make larger displacements of the articulatory organs relative to the size of their faces (Riley & Smith, 2003).…”

“…For some children, accuracy pronouncing speech sounds might develop slowly or with disorder (Velleman, 2016). The particular causes for difficulty might be associated with trouble (a) perceiving the sounds (Liu, Kuhl, & Tsao, 2003;Yoshinaga-Itano, Coulter, & Thomson, 2000;Velleman, 1988), (b) cognitively processing speech sounds in association with linguistic information (Jusczyk, 1999), and/or (c) executing the speech movements (Bauman-Waengler, 2012;Caruso & Strand, 1999;Kent, 2000;Ozanne, 2013;Smith, 2010;Vuolo & Goffman, 2017). For children with WS or Dup7, reports suggest many have difficulty learning to speak clearly (Gosch, Städing, & Pankau, 1994;Semel & Rosner, 2003;Udwin & Yule, 1990;.…”

Changes in movement transitions across a practice period in childhood apraxia of speech

“…There is also evidence that children with CAS produce more variable articulator movements than children with other speech sound disorders (Grigos et al, 2015; Moss & Grigos, 2012). Two studies have built upon past research to examine the impact of practice on sound production and articulatory control in children with CAS (Case & Grigos, 2016; Vuolo & Goffman, 2016). Vuolo and Goffman (2016) examined changes in speech production and movement variability in nine children (5–6 years of age), two of which were diagnosed with CAS, within the context of an imitation and retrieval task.…”

“…Two studies have built upon past research to examine the impact of practice on sound production and articulatory control in children with CAS (Case & Grigos, 2016; Vuolo & Goffman, 2016). Vuolo and Goffman (2016) examined changes in speech production and movement variability in nine children (5–6 years of age), two of which were diagnosed with CAS, within the context of an imitation and retrieval task. Children tended to demonstrate an increase in spatial and temporal variability across a period of five practice periods.…”

“…In the CAS group, we predict that the movement from consonant to vowel will be refined with practice and characterized by decreased movement duration, displacement and variability over time. These kinematic parameters are selected as prior research involving children with CAS has shown that they are sensitive to change (Grigos et al, 2015; Terband et al, 2011; Vuolo & Goffman, 2016). Further, we hypothesize that changes seen in practiced tokens will not generalize to unpracticed tokens given the speech motor deficits associated with CAS.…”