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Permanent URI for this collectionhttps://eresearch.qmu.ac.uk/handle/20.500.12289/22
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Item Improving ultrasound post estimation accuracy by training on co-registered EMA data(University of Aizu, 2024-06-28) Balch-Tomes, Jonathan; Wrench, Alan A.; Scobbie, James M.; Macmartin, C.; Turk, A.This study aims to assess how accurately DeepLabCut [1], when applied to ultrasound tongue images, can estimate Electromagnetic Articulography (EMA) sensor positions. EMA provides objective measures of anterior tongue, jaw, and lip kinematics. DeepLabCut pose estimation is a powerful method of extracting keypoint positions from midsagittal ultrasound images of the tongue. It has an advantage over EMA in that it can be applied to the whole of the tongue from tip to root as well as the jaw and the hyoid. After correction for probe translation standard error in the estimation of keypoint positions compared to the corresponding EMA sensor positions was 1.2-1.5mm along the tongue contour and 0.5-0.9mm perpendicular to the tongue contour.Item Similar and different tongue surface contours: intra-speaker controls in ultrasound analysis(2023-08) Scobbie, James M.Ultrasound studies of speech production analyse differences in dependent variables reflecting the tongue surface’s location and shape. Inferential statistics distinguish theoretically-relevant from random effects, somewhat independently of the descriptive size of significant effects. Experimental designs induce measurable dependent changes by manipulating independent variables such as prosody, phonemic target, etc. This paper presents descriptive statistics quantifying holistically all 15 pairwise differences between six monophthongal long vowel phonemes of one variety of English, comparing these to experimental noise differences attributable to the use of two identical blocks of data collection in sequence. Eight speakers were recorded, using two different ultrasound systems, and analysed in AAA using both edge-tracking and DeepLabCut pose estimation. The smallest phonemic contrast (~2mm) was greater than the experimental noise (~1mm), and was well evidenced by AAA’s t-test of radial difference.Item Say again? Individual articulatory strategies for producing a clearly-spoken minimal pair wordlist(International Phonetic Association, 2019-08-10) Scobbie, James M.; Ma, Joan K-YWe describe articulatory differences (lingual and labial) between two versions (neutral and clear) of a CVC wordlist of 12 targets (V = /ieaɔoʉ/; C_C = /p_p/ or /m_m/). A companion paper describes the background; the participants, materials and tasks; the impressionistic and acoustic results. Labial measures reflect vowel opening (and edge-spreading) and consonant compression using fleshpoint markers captured by head-mounted video. Consonant closure and total word duration are based on visual judgement of complete closure. Ultrasound data provides the absolute area between neutral and clear mid-sagittal tongue-surface splines at the maximum of each vowel target, and a qualitative description of tongue shape and location. Strong and systematic interspeaker variation was evident in how articulation, acoustics and functional clarity were enhanced. Some large phonologically motivated segmental hyperspeech enhancements were observed, but they were not related straightforwardly to the phonological oppositions in the material nor consistently used by all speakers. Differences in utterance initiation are also discussed.Item Tongue shape dynamics in swallowing using sagittal ultrasound(Springer, 2018-06-28) Ohkubo, Mai; Scobbie, James M.Ultrasound imaging is simple, repeatable, gives real-time feedback, and its dynamic soft tissue imaging may make it superior to other modalities for swallowing research. We tested this hypothesis and measured certain spatial and dynamic aspects of the swallowing to investigate its efficacy. Eleven healthy adults wearing a headset to stabilize the probe participated in the study. Both thickened and thin liquids were used, and liquid bolus volumes of 10 and 25 ml were administered to the subjects by using a cup. The tongue's surface was traced as a spline superimposed on a fan-shaped measurement space for every image from the time at which the tongue blade started moving up toward the palate at the start of swallowing to the time when the entire tongue was in contact with the palate. To measure depression depth, the distance (in mm) was measured along each radial fan line from the location at which the tongue's surface spline intersected the fan line to the point where the hard palate intersected the fan line at each timepoint. There were differences between individual participants in the imageability of the swallow, and so we defined quantitatively "measureable" and "unmeasurable" types. The most common type was measureable, in which we could find a clear bolus depression in the cupped tongue's surface. Indeed, with 10 ml of thin liquids, we were able to find and measure the depression depth for all participants. The average maximum radial distance from the palate to the tongue's surface was 20.9 mm (median) (IQR: 4.3 mm) for swallowing 10 ml of thin liquid compared to 24.6 mm (IQR: 3.3 mm) for 25 ml of thin liquid swallow (p < 0.001). We conclude that it is possible to use ultrasound imaging of the tongue to capture spatial aspects of swallowing.Item Biological and social grounding of phonology : variation as a research tool(2007-08) Scobbie, James M.; Acknowledgements. Financial support from ESRC (RES-000-22-2032).Phonological-phonetic sound systems are abstractions away from substance, so while they are grounded in biological capacity, they also reflect phonetically un-natural relationships arising from a variety of linguistic factors. Sociolinguistic variation is one of these non-biological factors. Pilot articulatory results are presented from derhoticised Scottish English. It can have onset/ coda allophony far more radical than the systems that are normally examined in articulatory research. Ultrasound analysis shows acoustic rhoticity in codas may have a post-alveolar constriction so delayed that acoustic rhoticity is covert. Perceptual recoverability of social identity has to be considered in addition to plain phonetic factors.Item Articulation therapy for children with cleft palate using visual articulatory models and ultrasound biofeedback(International Phonetic Association, 2015-08-15) Roxburgh, Zoe; Scobbie, James M.; Cleland, JoanneVisual biofeedback tools, such as Electropalatography (EPG), are recommended for assessing and treating speech sound disorders (SSDs) associated with Cleft Palate (CP). However, EPG is not suitable for all clients, due to dependencies on stable dentition and timing of palatal repair. Ultrasound is becoming increasingly popular for its use in treating SSDs, with no reports on its dependency on structure of the vocal tract. However its clinical application in the CP population remains to be tested. We compared Visual Articulatory Models (VAMs) with Ultrasound for the treatment of SSDs in two children with repaired submucous CP. Both children received two blocks of therapy each with eight sessions, with the first block using VAMs and the second using ultrasound. Results showed that both children improved overall, with more improvement found in the first block of therapy using VAMs.Item The role of anterior lingual gesture delay in coda /r/ lenition: An ultrasound tongue imaging study(International Phonetic Association, 2015-08-15) Lawson, Eleanor; Scobbie, James M.; Stuart-Smith, JaneWe investigate the contribution that lingual gesture delay makes to lenition of postvocalic /r/. This study uses a socially-stratified, audio-ultrasound corpus of Scottish English containing recordings from two sociolects; one with postvocalic /r/ weakening and the other with strengthening. We quantify auditory strength of rhoticity and the timing of the anterior lingual gesture relative to the offset of voicing in CVr words: bar, bore, fur, or onset of a following consonant in CVrC words: farm, herb, burp, in order to show that there is a statistically significant correlation between weak rhoticity and a late articulatory gesture. Our ultrasound data also show that during the process of final consonant vocalization/deletion, underlying articulatory gestures may persist.Item Morphological effects on pronunciation(International Phonetic Association, 2015-08-15) Mousikou, P.; Strycharczuk, Patrycja; Turk, Alice; Rastle, K.; Scobbie, James M.Converging, albeit inconsistent, empirical evidence suggests that the morphological structure of a word influences its pronunciation. We investigated this issue using Ultrasound Tongue Imaging in the context of an experimental cognitive psychology paradigm. Scottish speakers were trained on apparently homophonous monomorphemic and bimorphemic novel words (e.g. zord, zorred), and tested on speech production tasks. Monomorphemic items were realised acoustically with shorter durations than bimorphemic items; however, this difference was not statistically significant. Progressive coarticulatory effects were also observed in the monomorphemic condition for some speakers. A dynamic analysis of the articulatory data revealed that the observed differences in the pronunciations of the two types of items could be due to factors other than morphological structure. Our results, albeit inconclusive, make a significant contribution to the literature in this research domain insofar as the presence or absence of morphological effects on pronunciation has important implications for extant theories of speech production.Item Helping children learn non-native articulations: The implications for ultrasound-based clinical intervention(International Phonetic Association, 2015-08-15) Cleland, Joanne; Scobbie, James M.; Nakai, Satsuki; Wrench, Alan A.An increasing number of studies are examining the effectiveness of ultrasound as a visual biofeedback device for speech production training or therapy. However, no randomised control trials exist. We compared the success of typically-developing children learning new articulations with and without ultrasound biofeedback. Thirty children aged 6-12 were randomly assigned to 2 groups: Group U were taught novel (non-English) consonants and vowels using ultrasound in addition to imitation, modelling, articulatory descriptions and feedback on performance. Group A were taught the same speech sounds, using the same methods but in the absence of ultrasound visual biofeedback. Results showed that both groups of children improved in their production of the novel sounds with the exception of the high back vowels [u,]. No advantage for Group U was found, except for the palatal stop [c].Item Velocity measures in ultrasound data. Gestural timing of post-vocalic /l/ in English(International Phonetic Association, 2015-08-15) Strycharczuk, Patrycja; Scobbie, James M.We propose a new method for extracting dynamic information from midsagittal ultrasound images of tongue shape and location. The method is based on analysing parts of the tongue contour as they appear to travel up and down fan lines at key articulatory locations, representing velar and alveolar constrictions. The tongue displacement in these dimensions serves as the basis for calculating instantaneous velocity, whose maxima and minima help to define articulatory events. We validate the proposed method using data on /l/-darkening in Standard Southern British English. Our analysis extracts systematic information about the relative timing of gestures involved in the articulation of post-vocalic /l/, and it provides the basis for selecting representative images of consonantal constriction.