Caractérisation acoustico-phonétique de parole provenant de patients atteints de paralysies faciales

National audienceLa caractérisation de la parole pathologique est un problème important pour la détection et le diagnostic précoces. La parole pathologique étudiée dans cet article, provient de patients paralysés faciaux, souffrant notamment de problèmes de prononciation des plosives. Plusieurs paramètres sont extraits d’un détecteur automatique de bursts en vue de caractériser cette altération. L’une des autres hypothèses étudiées ici est que les cibles vocaliques souffrent de la mauvaise prononciation des consonnes, et ont une réalisation approximative. Une analyse des voyelles et des bursts est donc proposée en fonction des différents grades de sévérité de la paralysie des patients. Une diminution significative du nombre de bursts, des écart-type des durées de ceux-ci et du F2 des voyelles /i, e, E, a/ ont été observés pour les patients du corpus. Le F3 des voyelles /i, y/ est affecté, montrant que les patients ont du mal à produire ces voyelles, faisant intervenir les lèvres

Automatic Assessment of Speech Capability Loss in Disordered Speech

International audienceIn this article, we report on the use of an automatic technique to assess pronunciation in the context of several types of speech disorders. Even if such tools already exist, they are more widely used in a different context, namely, Computer-Assisted Language Learning, in which the objective is to assess nonnative pronunciation by detecting learners' mispronunciations at segmental and/or suprasegmental levels. In our work, we sought to determine if the Goodness of Pronunciation (GOP) algorithm, which aims to detect phone-level mispronunciations by means of automatic speech recognition, could also detect segmental deviances in disordered speech. Our main experiment is an analysis of speech from people with unilateral facial palsy. This pathology may impact the realization of certain phonemes such as bilabial plosives and sibilants. Speech read by 32 speakers at four different clinical severity grades was automatically aligned and GOP scores were computed for each phone realization. The highest scores, which indicate large dissimilarities with standard phone realizations, were obtained for the most severely impaired speakers. The corresponding speech subset was manually transcribed at phone level; 8.3% of the phones differed from standard pronunciations extracted from our lexicon. The GOP technique allowed the detection of 70.2% of mispronunciations with an equal rate of about 30% of false rejections and false acceptances. Finally, to broaden the scope of the study, we explored the correlation between GOP values and speech comprehensibility scores on a second corpus, composed of sentences recorded by six people with speech impairments due to cancer surgery or neurological disorders. Strong correlations were achieved between GOP scores and subjective comprehensibility scores (about 0.7 absolute). Results from both experiments tend to validate the use of GOP to measure speech capability loss, a dimension that could be used as a complement to physiological measures in pathologies causing speech disorders

Langage et gliomes de bas grade (étude des modalités d accès lexical en fonction du temps opératoire)

La chirurgie des gliomes, tumeurs cérébrales primitives intra-parenchymateuses, reste controversée, en raison de ses possibles conséquences fonctionnelles lorsque la lésion est située dans des zones dites éloquentes du langage. Les perturbations aphasiques peuvent être dues au développement de la tumeur, et/ou au traitement médical, le manque du mot étant le symptôme le plus fréquent. Nous avons abordé l accès lexical selon plusieurs modalités (visuelle à l oral et à l écrit, auditive et liée à la mémoire à court terme), en analysant sur un mode longitudinal les facteurs susceptibles d influencer la performance de 32 sujets atteints de gliomes de bas grade. Nous leur avons proposé un protocole de dix épreuves à trois reprises : avant, pendant et après l intervention. Nos recherches ont montré : (a) la présence de troubles dès le préopératoire, notamment dans deux épreuves (épreuve de dénomination orale d images et épreuve de fluence sémantique), leur aggravation en postopératoire immédiat quelle que soit la localisation lésionnelle et hémisphérique, et leur récupération progressive ; (b) la grande variabilité interindividuelle des performances, non réductibles à leur localisation. Elles confirment également la nécessité d une évaluation longitudinale visant à adapter les traitements de manière de plus en plus individualisée, pour minimiser les risques d atteinte langagière définitive.PARIS-BIUSJ-Physique recherche (751052113) / SudocSudocFranceF

Functional compensation of the claustrum: lessons from low-grade glioma surgery.

In functional magnetic resonance imaging (fMRI) data analysis, effective connectivity investigates the influence that brain regions exert on one another. Structural equation modeling (SEM) has been the main approach to examine effective connectivity. In this paper, we propose a method that, given a set of regions, performs partial correlation analysis. This method provides an approach to effective connectivity that is data driven, in the sense that it does not require any prior information regarding the anatomical or functional connections. To demonstrate the practical relevance of partial correlation analysis for effective connectivity investigation, we reanalyzed data previously published [Bullmore, Horwitz, Honey, Brammer, Williams, Sharma, 2000. How good is good enough in path analysis of fMRI data? NeuroImage 11, 289-301]. Specifically, we show that partial correlation analysis can serve several purposes. In a pre-processing step, it can hint at which effective connections are structuring the interactions and which have little influence on the pattern of connectivity. As a post-processing step, it can be used both as a simple and visual way to check the validity of SEM optimization algorithms and to show which assumptions made by the model are valid, and which ones should be further modified to better fit the data

Superior longitudinal fasciculus subserves vestibular network in humans.

Vestibular function is known to be represented in a large-scale network within the brain. Although much is known about the topography of this cortical network, the subcortical anatomo-functional connectivity has received less attention. We present three patients operated on while conscious for cerebral low-grade gliomas, in which we elicited vestibular symptoms during subcortical stimulation. Anatomo-functional correlations between postoperative imaging and intraoperative findings suggest the involvement of the superior longitudinal fasciculus in the spreading of the vestibular symptoms. We argue that this fasciculus plays a major role in the functional connectivity of the areas involved in the complex multimodal network that controls vestibular function

The insular lobe and brain plasticity: Lessons from tumor surgery.

OBJECTIVES: Despite recent literature supporting the likely role of the insula in many functions, the actual participation of this multimodal lobe in the brain functioning remains unclear, i.e. has the insula an essential or compensable role? PATIENTS AND METHODS: We surgically resected an insular low-grade glioma, using intraoperative electrical stimulation, in 42 patients who experienced seizures, but who presented no or only a slight neurological deficit. Surgery was performed under local anesthesia in patients with a lesion in the dominant hemisphere. The resection was systematically stopped according to cortico-subcortical functional boundaries. RESULTS: Intraoperative electrical mapping induced language disturbances, pain and vertigo, but no other side effects were observed. Post-operatively, the patients experienced a transient hemiparesis in 21 cases, language disorders in 10 cases, an athymhormic syndrome in 7 cases, a Foix-Chavany-Marie syndrome in 3 cases, and micturition disturbances in one case. Despite this immediate post-surgical worsening, all the patients recovered their preoperative neurological status within 3 months, except in three cases due to a deep stroke. CONCLUSION: These results show that the insula, a complex associative multimodal structure poorly studied until now, can be functionally compensated. Such a plastic potential may have important fundamental and clinical implications, in particular in the field of oncological neurosurgery

Intérêt d’un dispositif pédagogique de type

Contexte : La méthode Jigsaw ou « classe puzzle » est une approche pédagogique développée aux États-Unis qui redéfinit les rôles de chacun, enseignants et apprenants, dans l’apprentissage. Nous l’avons appliquée à la formation à la lecture labiale des étudiantes de troisième année d’orthophonie. But : Le but était d’évaluer l’efficacité en termes d’amélioration des compétences et la perception de l’intérêt pédagogique de cette méthode par les étudiantes de troisième année du premier cycle d’études en orthophonie. Cet enseignement a été proposé en visioconférence pendant la crise sanitaire. Méthodes : Six groupes de 18 étudiantes ont participé aux enseignements sous forme de deux séances de travaux dirigés. L’évaluation et l’auto-évaluation de la lecture labiale, ainsi que le retour sur le procédé pédagogique ont été recueillis de façon anonyme. Résultats : La compétence en lecture labiale et le sentiment d’auto-efficacité s’améliorent après les deux séances de travaux dirigés. Le procédé pédagogique est jugé intéressant, dynamique et concret par les étudiantes. Conclusion : L’approche Jigsaw a permis de rendre l’enseignement de lecture labiale plus vivant et d’améliorer les compétences des étudiantes de troisième année d’orthophonie. Des études ultérieures permettront de comparer l’efficacité de cette approche par rapport aux méthodes pédagogiques traditionnellement utilisées en formation paramédicale, à savoir l’enseignement magistral et les travaux dirigés axés sur la discussion de cas cliniques

A discrete area within the left dorsolateral prefrontal cortex involved in visual-verbal incongruence judgment

The role of the frontal lobe in cross-modal visual--auditory processing has been documented in experiments using incongruent/ congruent paradigms. In this study, 4 patients with left frontal World Health Organization Grade II glioma were assessed during pre-, intra-, and postoperative sessions with picture-naming and verbal--visual task requiring judgment of congruence between pictures and words. During awake brain surgery, the naming and crossmodal tasks were coupled with electrical stimulation inactivating restricted specific regions. For all patients, focal brain stimulation in the dorsolateral prefrontal cortex elicited picture--word matching disturbances but no naming impairment, and the elicited errors exclusively appeared in incongruent and not congruent conditions. The dissociation observed between correct picture naming and disturbed cross-modal judgment shows that electrical stimulation of a discrete cortical area within the left dorsolateral prefrontal cortex can inhibit the simultaneous processing of visual--verbal information without disturbing larger networks involved in the naming process