239 research outputs found
Prospective Validation of Motor-Based Intervention with Automated Mispronunciation Detection of Rhotics in Residual Speech Sound Disorders
Because lab accuracy of clinical speech technology systems may be
overoptimistic, clinical validation is vital to demonstrate system
reproducibility - in this case, the ability of the PERCEPT-R Classifier to
predict clinician judgment of American English /r/ during ChainingAI
motor-based speech sound disorder intervention. All five participants
experienced statistically-significant improvement in untreated words following
10 sessions of combined human-ChainingAI treatment. These gains, despite a wide
range of PERCEPT-human and human-human (F1-score) agreement, raise questions
about best measuring classification performance for clinical speech that may be
perceptually ambiguous.Comment: To appear in Proceedings of the Annual Conference of the
International Speech Communication Association, INTERSPEECH 202
Biofeedback interventions
Biofeedback interventions use instrumentation to allow the speaker to visualise and modify their own speech production in real-time. This chapter focuses on three types of biofeedback used for treating children with speech disorders: Electropalatography (EPG), ultrasound, and acoustic biofeedback. EPG and ultrasound show real time articulatory movements while acoustic biofeedback uses either a spectrogram or linear predictive coding spectrum to distinguish speech sounds. All of the techniques are incorporated into a motor-learning paradigm where the visual display provides specific information about the nature of the articulatory or acoustic parameters required to produce accurate speech. Biofeedback is normally used to help school-aged children and adults with a wide variety of different types of speech sound disorders acquire lingual speech sounds which they have not acquired in the course of normal development. There is an emerging evidence base, currently consisting primarily of a large number of case studies and single case experimental designs, pointing towards the effectiveness of biofeedback
Classifying Rhoticity of /r/ in Speech Sound Disorder using Age-and-Sex Normalized Formants
Mispronunciation detection tools could increase treatment access for speech
sound disorders impacting, e.g., /r/. We show age-and-sex normalized formant
estimation outperforms cepstral representation for detection of fully rhotic
vs. derhotic /r/ in the PERCEPT-R Corpus. Gated recurrent neural networks
trained on this feature set achieve a mean test participant-specific F1-score
=.81 ({\sigma}x=.10, med = .83, n = 48), with post hoc modeling showing no
significant effect of child age or sex.Comment: To appear in Proceedings of the Annual Conference of the
International Speech Communication Association, INTERSPEECH 202
Acoustic-to-Articulatory Speech Inversion Features for Mispronunciation Detection of /r/ in Child Speech Sound Disorders
Acoustic-to-articulatory speech inversion could enhance automated clinical
mispronunciation detection to provide detailed articulatory feedback
unattainable by formant-based mispronunciation detection algorithms; however,
it is unclear the extent to which a speech inversion system trained on adult
speech performs in the context of (1) child and (2) clinical speech. In the
absence of an articulatory dataset in children with rhotic speech sound
disorders, we show that classifiers trained on tract variables from
acoustic-to-articulatory speech inversion meet or exceed the performance of
state-of-the-art features when predicting clinician judgment of rhoticity.
Index Terms: rhotic, speech sound disorder, mispronunciation detectionComment: *denotes equal contribution. To appear in Proceedings of the Annual
Conference of the International Speech Communication Association, INTERSPEECH
202
Developing a weighted measure of speech sound accuracy
Purpose: To develop a system for numerically quantifying a speaker's phonetic accuracy through transcription-based measures. With a focus on normal and disordered speech in children, the authors describe a system for differentially weighting speech sound errors on the basis of various levels of phonetic accuracy using a Weighted Speech Sound Accuracy ( WSSA) score. The authors then evaluate the reliability and validity of this measure. Method: Phonetic transcriptions were analyzed from several samples of child speech, including preschoolers and young adolescents with and without speech sound disorders and typically developing toddlers. The new measure of phonetic accuracy was validated against existing measures, was used to discriminate typical and disordered speech production, and was evaluated to examine sensitivity to changes in phonetic accuracy over time. Reliability between transcribers and consistency of scores among different word sets and testing points are compared. Results: Initial psychometric data indicate that WSSA scores correlate with other measures of phonetic accuracy as well as listeners' judgments of the severity of a child's speech disorder. The measure separates children with and without speech sound disorders and captures growth in phonetic accuracy in toddlers' speech over time. The measure correlates highly across transcribers, word lists, and testing points. Conclusion: Results provide preliminary support for the WSSA as a valid and reliable measure of phonetic accuracy in children's speech. O ne of the continuing needs in the fields of developmental phonology and speech-language pathology is for accurate, sensitive, and viable measures of speech production for research and clinical practice Measurement issues are not trivial. A recent study of "independent measures" used to describe the productive phonology of toddlers withou
Evolutionary relationships between Rhynchosporium lolii sp. nov. and other Rhynchosporium species on grass.
Copyright: 2013 King et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are creditedThe fungal genus Rhynchosporium (causative agent of leaf blotch) contains several host-specialised species, including R. commune (colonising barley and brome-grass), R. agropyri (couch-grass), R. secalis (rye and triticale) and the more distantly related R. orthosporum (cocksfoot). This study used molecular fingerprinting, multilocus DNA sequence data, conidial morphology, host range tests and scanning electron microscopy to investigate the relationship between Rhynchosporium species on ryegrasses, both economically important forage grasses and common wild grasses in many cereal growing areas, and other plant species. Two different types of Rhynchosporium were found on ryegrasses in the UK. Firstly, there were isolates of R. commune that were pathogenic to both barley and Italian ryegrass. Secondly, there were isolates of a new species, here named R. lolii, that were pathogenic only to ryegrass species. R. lolii was most closely related to R. orthosporum, but exhibited clear molecular, morphological and host range differences. The species was estimated to have diverged from R. orthosporum ca. 5735 years before the present. The colonisation strategy of all of the different Rhynchosporium species involved extensive hyphal growth in the sub-cuticular regions of the leaves. Finally, new species-specific PCR diagnostic tests were developed that could distinguish between these five closely related Rhynchosporium species.Peer reviewedFinal Published versio
Measurements of the Sensitivity of Aerosol Hygroscopicity and the kappa Parameter to the O/C Ratio
Discovery of a Sub-Parsec Radio Counterjet in the Nucleus of Centaurus A
A sub-parsec scale radio counterjet has been detected in the nucleus of the
closest radio galaxy, Centaurus A (NGC 5128), with VLBI imaging at 2.3 and 8.4
GHz. This is one of the first detections of a VLBI counterjet and provides new
constraints on the kinematics of the radio jets emerging from the nucleus of
Cen A. A bright, compact core is seen at 8.4 GHz, along with a jet extending
along P.A. 51 degrees. The core is completely absorbed at 2.3 GHz. Our images
show a much wider gap between the base of the main jet and the counterjet at
2.3 GHz than at 8.4 GHz and also that the core has an extraordinarily inverted
spectrum. These observations provide evidence that the innermost 0.4-0.8 pc of
the source is seen through a disk or torus of ionized gas which is opaque at
low frequencies due to free-free absorption.Comment: 3 pages, 2 postscript figures, scheduled for publication in August 1,
1996 issue of Ap.J. Letter
Direct magnetic field detection in the innermost regions of an accretion disc
Models predict that magnetic fields play a crucial role in the physics of
astrophysical accretion disks and their associated winds and jets. For example,
the rotation of the disk twists around the rotation axis the initially vertical
magnetic field, which responds by slowing down the plasma in the disk and by
causing it to fall towards the central star. The magnetic energy flux produced
in this process points away from the disk, pushing the surface plasma outwards,
leading to a wind from the disk and sometimes a collimated jet. But these
predictions have hitherto not been supported by observations. Here we report
the direct detection of the magnetic field in the core of the protostellar
accretion disk FU Orionis. The surface field reaches strengths of about 1 kG
close to the centre of the disk, and it includes a significant azimuthal
component, in good agreement with recent models. But we find that the field is
very filamentary and slows down the disk plasma much more than models predict,
which may explain why FU Ori fails to collimate its wind into a jet.Comment: 11 pages, 3 figure
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