An Articulatory Analysis of American English Rhotics in Children With and Without a History of Residual Speech Sound Disorder.

This study investigated articulatory patterns for American English /ɹ/ in children with and without a history of residual speech sound disorder (RSSD). It was hypothesized that children without RSSD would favor bunched tongue shapes, similar to American adults reported in previous literature. Based on clinical cueing practices, it was hypothesized that children with RSSD might produce retroflex tongue shape patterns at a higher relative rate. Finally, it was hypothesized that, among children who use a mixture of bunched and retroflex shapes, phonetic context would impact tongue shape as reported in the adult literature. These hypotheses were tested using ultrasound data from a stimulability task eliciting /ɹ/ in syllabic, postvocalic, and onset contexts. Participants were two groups of children/adolescents aged 9-15 years: 36 with RSSD who completed a study of ultrasound biofeedback treatment and 33 with no history of RSSD. Tongue shapes were qualitatively coded as bunched or retroflex using a flowchart from previous research. Children with no history of RSSD were found to use bunched-only tongue shape patterns at a rate higher than adults, but those who used a mixture of shapes for /ɹ/ followed the expected phonetic contextual patterning. Children with RSSD were found to use retroflex-only patterns at a substantially higher rate than adults, and those using a mixture of shapes did not exhibit the expected patterning by phonetic context. These findings suggest that clients receiving ultrasound biofeedback treatment for /ɹ/ may be most responsive to clinician cueing of retroflex shapes, at least early on. However, retroflex-only cueing may be a limiting and insufficient strategy, particularly in light of our finding of a lack of typical variation across phonetic contexts in children with remediated /ɹ/. Future research should more specifically track cueing strategies to better understand the relationship between clinician cues, tongue shapes, and generalization across a range of contexts. https://doi.org/10.23641/asha.26801050.