Acoustic analysis of the unvoiced stop consonants for detecting hypernasal speech

Speakers having evidence of a defective velopharyngeal mechanism produce speech with inappropriate nasal resonance (hypernasal speech). Voice analysis methods for the detection of hypernasality commonly use vowels and nasalized vowels. However, to obtain a more general assessment of this abnormality it is necessary to analyze stops and fricatives. This study describes a method for hipernasality detection analyzing the unvoiced Spanish stop consonants /k/ and /p/, as well. The importance of phonemeby- phoneme analysis is shown, in contrast with whole word parametrization which may include irrelevant segments from the classification point of view. Parameters that correlate the imprints of Velopharyngeal Incompetence (VPI) over voiceless stop consonants were used in the feature estimation stage. Classification was carried out using a Support Vector Machine (SVM), obtaining a performance of 74% for a repeated cross-validation strategy evaluation

Articulation therapy for children with cleft palate using visual articulatory models and ultrasound biofeedback

Visual 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

DIA : a tool for objective intelligibility assessment of pathological speech

Intelligibility is generally accepted to be a very relevant measure in the assessment of pathological speech. In clinical practice, intelligibility is measured using one of the many existing perceptual tests. These tests usually have the drawback that they employ unnatural speech material (e.g. nonsense words) and that they cannot fully exclude errors due to the listener's bias. This raises the need for an objective and automated tool to measure intelligibility. Here, we present the Dutch Intelligibility Assessment (DIA), an objective tool that aids the speech therapist in evaluating the intelligibility of persons with pathological speech. This tool will soon be made publicly available

Comparison of motor-phonetic versus phonetic-phonological speech therapy approaches in patients with a cleft (lip and) palate : a study in Uganda

INTRODUCTION : At present, there is growing interest in combined phonetic-phonological approaches to treat active speech errors in children with a cleft (lip and) palate (CP ± L). Unfortunately, evidence for these type of speech interventions in this population is lacking. Therefore, the present study investigated the effectiveness of speech intervention in Ugandan patients with CP ± L. Moreover, a comparison was made between a motor-phonetic and a phonetic-phonological speech intervention. METHODS : Eight patients (median age: 11.26y) with an isolated CP ± L were assigned into a group receiving motor-phonetic treatment (n = 4) or a group receiving combined phonetic-phonological treatment (n = 4). The participants received 6h of individual speech therapy. In both groups, perceptual and instrumental speech evaluations were performed to evaluate the patients' speech before and after the intervention. RESULTS : Speech therapy (irrespective of the used approach) was found to be effective in increasing consonant proficiency and in decreasing the occurrence of non-oral and passive CSCs. No statistically significant differences in outcome variables were found when comparing the two groups pre- and post-treatment. The descriptive results, however, revealed a larger increase in % correctly produced consonants, places and manners after the intervention in the group receiving a combined phonetic-phonological treatment compared to the group receiving a motor-phonetic treatment. CONCLUSION : This study took a first step in providing evidence concerning the effectiveness of different speech therapy approaches in children with CP ± L. The present study holds some important implications for clinical practice suggesting that an additional phonological approach may be beneficial for the patients with CP ± L. Further research including randomized controlled trials with larger sample sizes is necessary to provide further evidence.A PhD grant of the Research Fund Flanders (1120919N).https://www.elsevier.com/locate/ijporl2021-04-01hj2020Speech-Language Pathology and Audiolog

Automatic analysis of pathological speech

De ernst van een spraakstoornis wordt vaak gemeten a.d.h.v. spraakverstaanbaarheid. Deze maat wordt in de klinische praktijk vaak bepaald met een perceptuele test. Zo’n test is van nature subjectief vermits de therapeut die de test afneemt de (stoornis van de) patiënt vaak kent en ook vertrouwd is met het gebruikte testmateriaal. Daarom is het interessant te onderzoeken of men met spraakherkenning een objectieve beoordelaar van verstaanbaarheid kan creëren. In deze thesis wordt een methodologie uitgewerkt om een gestandaardiseerde perceptuele test, het Nederlandstalig Spraakverstaanbaarheidsonderzoek (NSVO), te automatiseren. Hiervoor wordt gebruik gemaakt van spraakherkenning om de patiënt fonologisch en fonemisch te karakteriseren en uit deze karakterisering een spraakverstaanbaarheidsscore af te leiden. Experimenten hebben aangetoond dat de berekende scores zeer betrouwbaar zijn. Vermits het NSVO met nonsenswoorden werkt, kunnen vooral kinderen hierdoor leesfouten maken. Daarom werden nieuwe methodes ontwikkeld, gebaseerd op betekenisdragende lopende spraak, die hiertegen robuust zijn en tegelijk ook in verschillende talen gebruikt kunnen worden. Met deze nieuwe modellen bleek het mogelijk te zijn om betrouwbare verstaanbaarheidsscores te berekenen voor Vlaamse, Nederlandse en Duitse spraak. Tenslotte heeft het onderzoek ook belangrijke stappen gezet in de richting van een automatische karakterisering van andere aspecten van de spraakstoornis, zoals articulatie en stemgeving

Automatic Screening of Childhood Speech Sound Disorders and Detection of Associated Pronunciation Errors

Speech disorders in children can affect their fluency and intelligibility. Delay in their diagnosis and treatment increases the risk of social impairment and learning disabilities. With the significant shortage of Speech and Language Pathologists (SLPs), there is an increasing interest in Computer-Aided Speech Therapy tools with automatic detection and diagnosis capability. However, the scarcity and unreliable annotation of disordered child speech corpora along with the high acoustic variations in the child speech data has impeded the development of reliable automatic detection and diagnosis of childhood speech sound disorders. Therefore, this thesis investigates two types of detection systems that can be achieved with minimum dependency on annotated mispronounced speech data. First, a novel approach that adopts paralinguistic features which represent the prosodic, spectral, and voice quality characteristics of the speech was proposed to perform segment- and subject-level classification of Typically Developing (TD) and Speech Sound Disordered (SSD) child speech using a binary Support Vector Machine (SVM) classifier. As paralinguistic features are both language- and content-independent, they can be extracted from an unannotated speech signal. Second, a novel Mispronunciation Detection and Diagnosis (MDD) approach was introduced to detect the pronunciation errors made due to SSDs and provide low-level diagnostic information that can be used in constructing formative feedback and a detailed diagnostic report. Unlike existing MDD methods where detection and diagnosis are performed at the phoneme level, the proposed method achieved MDD at the speech attribute level, namely the manners and places of articulations. The speech attribute features describe the involved articulators and their interactions when making a speech sound allowing a low-level description of the pronunciation error to be provided. Two novel methods to model speech attributes are further proposed in this thesis, a frame-based (phoneme-alignment) method leveraging the Multi-Task Learning (MTL) criterion and training a separate model for each attribute, and an alignment-free jointly-learnt method based on the Connectionist Temporal Classification (CTC) sequence to sequence criterion. The proposed techniques have been evaluated using standard and publicly accessible adult and child speech corpora, while the MDD method has been validated using L2 speech corpora

Speech in Sri Lankan cleft palate subjects with delayed palatoplasty.

This investigation was undertaken within the context of the Sri Lankan Cleft Up and Palate Project, probably the largest surgical and research programme to date concerned with the late operated cleft lip and/or palate subject (Mars et al., 1990). This study examines the speech results of88 patients who received palatal surgery by a visiting British surgical team. The main cohort, consisting of 67 nonsyndromic cleft lip and/or palate Sinh ala speaking patients over the age of eight years at palate repair, have been studied longitudinally. All these patients have pre-operative, post-operative, and post-therapy speech recordings. In addition, 21 similar patients below the age of eight years at surgery have been partially examined. 51 patients have further speech recordings at 4 or 5 years post-operatively. Investigations of velopharyngeal function were undertaken using lateral skull X-rays of patients phonating "ee', nasopharyngoscopy, and a perceptual assessment. Post-operative intra-oral examinations were also carried out. A unique method of speech analysis has been devised, and is used to describe the speech results. The results have shown that patients who have established their speech with an unrepaired palate usually have severely disordered speech, with the exception of some patients with less severe clefts. Post-operatively, many patients retain these poor speech patterns, even with some speech therapy support. Post-therapy, only one third of the cohort had normal or near-normal speech, none of whom were adults. The value of palatal closure is very limited if regular speech therapy is not available as a follow-up to surgery. Only 20% of the cohort achieved post-operative velopharyngeal closure, suggesting that palatoplasty is an inadequate surgical procedure for the majority of patients, in particular those who present with major clefts and are older than eight years of age at surgery. The important variables affecting outcome are palatal repair, speech therapy intervention, age, cleft type, nature of pre-operative speech, and nature of surgery. Structural factors in particular velopharyngeal function and also possibly fistulae, in the adult group, are further relevant variables. Criteria for selecting patients for surgery within this type of environment are proposed

The Relationship between the Type of Cleft and Nasal Air Emission in Speech of Children with Cleft Palate or Cleft Lip and Palate

BACKGROUND: Cleft palate, due to damage of the soft palate, leads to dysfunction, i.e., inappropriate closure of the velopharynx during speech production, thus resulting in velopharyngeal insufficiency which characterises with hypernasal speech and nasal air loss/emission during speech production. AIM: To establish the relationship between the type of cleft according to the Veau classification and the degree of nasal air emission in the speech of patients with cleft using auditory-visual perceptual assessment procedures. MATERIAL AND METHODS: A group of 40 patients with irregular speech aged 4 to 7, out of which 20 with cleft palate or cleft lip and palate, participated in the research. The Veau classification was used to classify the cleft severity, while an indirect instrumental examination was conducted with the See-Scape instrument to detect nasal air emission during the speech. RESULTS: The respondents with cleft palate or cleft lip and palate of higher Veau class had a greater degree of nasal air emission during the speech. There is a positive, statistically significant correlation between the results obtained with the Veau classification of cleft lip and palate, and the degree of nasal air emission. The value of Spearman’s coefficient of correlation is R = 0.46, and the calculated p-value is p = 0.04. CONCLUSION: A more severe cleft type is associated with an increased degree of nasal air emission during the speech, and vice versa