Three-dimensional printable ultrasound transducer stabilization system

Reliability of Measuring Geniohyoid Cross-Sectional Area with B-Mode Ultrasound

B-mode ultrasound is a safe noninvasive procedure that has been used to characterize aspects of the oropharyngeal swallow. The submental suprahyoid muscles are often investigated with ultrasound because of their contributions to hyolaryngeal elevation. There are several techniques for positioning the ultrasound transducer in the coronal plane, however, there is limited research on how reliability of measurement of the cross-sectional area (CSA) of the geniohyoid differs across transducer placement technique. This study examined three methods of transducer placement in the coronal plane by two examiners to determine the reliability of measurement of CSA of the geniohyoid muscle. Forty healthy adults participated in the study. Each participant's geniohyoid muscles were imaged using B-mode ultrasound under three transducer placement conditions in the coronal plane by two examiners. Geniohyoid CSA was measured from each ultrasound image. A three-way mixed-methods ANOVA was used to determine whether there were significant differences in geniohyoid CSA among transducer position conditions, trials, and examiners. There were significant differences among the transducer placement conditions, indicating that each condition was measuring a different portion of the muscle. There were no significant differences among repeated trials nor between examiners within each method of transducer placement. All three conditions of transducer placement were reliable at measuring geniohyoid CSA across trials and examiners. This study emphasizes the need for consistency of placement, whichever method is selected. It also highlights the need for researchers to provide a precise description of methods for positioning the transducer so that placement is reproducible.

Effects of Production Training With Ultrasound Biofeedback on Production and Perception of Second-Language English Tense-Lax Vowel Contrasts

PURPOSE

This study investigated the efficacy of ultrasound biofeedback compared to a traditional acoustic input-only method in the second-language (L2) production training of English tense-lax vowel contrasts (/i-ɪ/ and /e-ɛ/). The relationship between the degrees of production and perception learning was also examined to explore a potential L2 production-perception link.

METHOD

Using a pretest/training/posttest paradigm, two groups of native Mandarin speakers received three sessions of training, one with ultrasound and one with audio only. Perception performance was measured by accuracy in AX discrimination. Production performance was measured in terms of accuracy in repetition production and Euclidean distance between contrasting vowels.

RESULTS

Both groups showed significant improvements in posttest production and perception tasks. Additionally, the training benefits were retained 6 weeks after training. The two groups, however, did not differ significantly in training gains; nor was there a significant correlation between training-induced changes in perception and production performance.

CONCLUSIONS

The results indicate that ultrasound feedback is similarly effective as the audio-only training in improving the L2 production of English tense-lax contrasts and the benefits transferred to perception. The lack of correlation between production and perception gains suggests that the two modalities need to be separately trained to achieve desired L2 learning outcomes.

Comparing metrics for quantification of children's tongue shape complexity using ultrasound imaging

Speech sound disorders can pose a challenge to communication in children that may persist into adulthood. As some speech sounds are known to require differential control of anterior versus posterior regions of the tongue body, valid measurement of the degree of differentiation of a given tongue shape has the potential to shed light on development of motor skill in typical and disordered speakers. The current study sought to compare the success of multiple techniques in quantifying tongue shape complexity as an index of degree of lingual differentiation in child and adult speakers. Using a pre-existing data set of ultrasound images of tongue shapes from adult speakers producing a variety of phonemes, we compared the extent to which three metrics of tongue shape complexity differed across phonemes/phoneme classes that were expected to differ in articulatory complexity. We then repeated this process with ultrasound tongue shapes produced by a sample of young children. The results of these comparisons suggested that a modified curvature index and a metric representing the number of inflection points best reflected small changes in tongue shapes across individuals differing in vocal tract size. Ultimately, these metrics have the potential to reveal delays in motor skill in young children, which could inform assessment procedures and treatment decisions for children with speech delays and disorders.