Why do children’s English /ɹ/ tongue shapes matter?

Research Abstract:

The English “r” sound /ɹ/ has received significant attention in adult and clinical literature with a focus on contrasting tongue shapes termed “bunched” and “retroflex” (Mielke et al., 2016). English /ɹ/ is considered one of the most difficult speech sounds to master, largely due to its articulatory complexity. Several studies have investigated remediation of residual distortions of /ɹ/ using ultrasound biofeedback (Sugden et al., 2019), but few studies have investigated children’s tongue shape patterns for /ɹ/. This study investigates the /ɹ/ articulation patterns in two groups of American English speaking children ages 9-15: 30 children with residual distortions of /ɹ/ who learned to produce perceptually accurate /ɹ/ during 10 weeks of ultrasound biofeedback treatment, and 36 children without residual distortions of /ɹ/. Using ultrasound data, the study explores whether children’s tongue shapes reflect adult patterns and whether the groups differ. The data include 2698 ultrasound images with 1760 images (65.2%) classified as bunched and 783 images (29%) classified as retroflex. For the group of children without residual distortions of /ɹ/, 93.9% of the tokens were bunched. For the group of children who received ultrasound biofeedback treatment, 69.8% of the tokens were retroflex. These images will undergo quantitative image analysis to assess coding reliability. Once complete, mixed logistic regression will be performed to explore interactions between tongue shape classifications, group, and phonetic context. Importantly, these results suggest the groups develop different articulatory patterns and children with residual distortions of /ɹ/ may benefit from retroflex clinician cueing.