Acoustic and articulatory studies demonstrate covert contrast in perceptually neutralised phonemic contrasts in both typical children and children with speech disorders. These covert contrasts are thought to be relatively common and symptomatic of phonetic speech disorders. However, clinicians in the speech therapy clinic have had no easy way of identifying this covertness. This study uses ultrasound tongue imaging to compare tongue contours for /t/ and /k/ in seven children with persistent velar fronting. We present a method of overlaying tongue contours to identify covert contrast at the articulatory level. Results show that all seven children, contrary to expectations, produced both /t/ and /k/ with near-identical tongue shapes showing no evidence of covert contrast. However, further analysis of one of the participants showed highly variable tongue shapes for /t/ and /k/, including retroflex productions of both. Although not phonologically conditioned, this covert error is evidence of speech disorder at the phonetic level.

We introduce UltraSuite, a curated repository of ultrasound and acoustic data, collected from recordings of child speech therapy sessions. This release includes three data collections, one from typically developing children and two from children with speech sound disorders. In addition, it includes a set of annotations, some manual and some automatically produced, and software tools to process, transform and visualise the data.

Purpose This study evaluated ultrasound visual biofeedback treatment for teaching new articulations to children with a wide variety of speech sound disorders. It was hypothesized that motor-based intervention incorporating ultrasound would lead to rapid acquisition of a range of target lingual gestures with generalization to untreated words. Method Twenty children aged 6–15 years with a range of mild to severe speech disorders affecting a variety of lingual targets enrolled in a case series with replication. Of these, 15 children completed the intervention. All of the children presented with a variety of errors. We therefore employed a target selection strategy to treat the most frequent lingual error. These individual speech targets were treated using ultrasound visual biofeedback as part of ten to twelve 1-hr intervention sessions. The primary outcome measure was percentage of target segments correct in untreated wordlists. Results Six children were treated for velar fronting; 3 children, for postalveolar fronting; 2 children, for backing alveolars to pharyngeal or glottal place; 1 child, for debuccalization (production of all onsets as [h]); 1 child, for vowel merger; and 2 children, for lateralized sibilants. Ten achieved the new articulation in the 1st or 2nd session of intervention, despite no children being readily stimulable for their target articulation before intervention. In terms of generalization, effect sizes for percentage of target segments correct ranged from no effect (5 children), small effect (1 child), medium effect (4 children), and large effect (5 children). Conclusions Ultrasound visual biofeedback can be used to treat a wide range of lingual errors in children with various speech sound disorders, from mild to severe. Visual feedback may be useful for establishing new articulations; however, generalization is more variable.

In Cleft Palate (CP) assessments based on phonetic transcription are the "gold standard" therapy outcome measure, despite reliability difficulties. Here we propose a novel perceptual evaluation, applied to ultrasound-visual biofeedback (U-VBF) therapy and therapy using visual articulatory models (VAMs) for two children with repaired submucous CP.Three comparisons were made: post VAM, post U-VBF and overall pre-and post-therapy. Twentytwo phonetically-trained listeners were asked to determine whether pre-or post-therapy recordings sounded "closer to the English target", using their own implicit stored knowledge (prompted via orthographic representation) as a comparison. Results are compared with segment-oriented percent target consonant correct (PTCC) derived from phonetic transcriptions by the authors.Listener judgements and PTCC suggest that both children made improvements using both VAM and U-VBF. Statistical analysis showed listener agreement across all three comparisons, despite agreement being poor. This perceptual evaluation offers a straightforward method of evaluating the effectiveness of interventions and can be used by phonetically trained or lay listeners.

Ultrasound Tongue Imaging is increasingly used during assessment and treatment of speech sound disorders. Recent literature has shown that ultrasound is also useful for the quantitative analysis of a wide range of speech errors. So far, the compensatory articulations of speakers with cleft palate have only been analysed qualitatively. This study provides a pilot quantitative ultrasound analysis, drawing on longitudinal intervention data from a child with submucous cleft palate. Two key ultrasound metrics were used: 1. articulatory t-tests were used to compare tongue-shapes for perceptually collapsed phonemes on a radial measurement grid and 2. the Mean Radial Difference was reported to quantify the extent to which the two tongue shapes differ, overall. This articulatory analysis supplemented impressionistic phonetic transcriptions and identified covert contrasts. Articulatory errors identified in this study using ultrasound were in line with errors identified in the speech of children with cleft palate in previous literature. While compensatory error patterns commonly found in speakers with cleft palate have been argued to facilitate functional phonological development, the nature of our findings suggest that the compensatory articulations uncovered are articulatory in nature.