The research in Clinical Phonetics aims to improve our knowledge of speech pathologies by comparing phonetic methods and research with clinical data and clinicians’ diagnoses. In France, Clinical Phonetics has developed over the last thirty years bringing together phoneticians, linguists, computer scientists, engineers, physicians, speech therapists and clinicians.The “Laboratoire Parole et Langage” (LPL) has a long experience in this field through many collaborations with local hospitals and other partners at the national level. These collaborations have led to the development of several projects dealing with a wide variety of pathologies (dysphonia, Parkinson’s disease, ALS, multiple sclerosis, cancers of the oral cavity and oropharynx, apraxia, etc.). Traditional phonetic methodologies (analysis of speech production and perception) have been adapted to the specific constraints of pathological speech. In particular, the LPL has strongly questioned and improved aerophonometry, speech intelligibility measurements, transcription of pathological speech, and acoustic analysis.There are many research questions in clinical phonetics, but they can be structured around two main axis: (1) what are the contributions of phonetics research to the assessment of speech pathologies?; (2) how can speech pathologies deepen our understanding of the complex mechanisms underlying speech production and perception? The goal of this work is twofold: first, to assist clinicians in the evaluation of the severity of a disorder, either for a punctual assessment or in a therapeutic evaluation (rehabilitation, surgical, pharmacological, electrophysiological treatment); secondly, to improve our knowledge on speech by characterizing the productions considered as “atypical”.Without being exhaustive, this chapter offers an overview of research in clinical phonetics at the LPL. After a brief history recalling the emergence of clinical phonetics at the LPL, we organized the chapter around the current work carried out at the LPL on laryngeal pathologies, motor disturbances, speech intelligibility and speech planning disorders.The first studies at LPL combining phonetics and clinical studies date back to the mid-1970s–1980s. These studies became a research focus at the LPL in the 1990s, thanks to formal collaborations with the ENT department of the Timone University Hospital in Marseilles. At that time, the main research interest for the ENT department was voice disorders analysis. This first research has continued to develop and the field of investigation has been extended to speech disorders, particularly those of neurological origin, such as motor or speech planning disorders, in which collaborations with the neurology department of the Pays d’Aix Hospital have been decisive. These clinical collaborations have also supported the valorization and dissemination of this research in the socio-economic world, in particular with the invention, manufacture and marketing of the Assisted Voice Evaluation (EVA) device.Laryngeal pathologies were the first area explored and have led to many publications. The establishment of vocal assessment, both at perceptual and instrumental level, has monopolized most of the efforts. Nevertheless, and in spite of the contribution of automatic speech processing, the instrumental approach derived from phonetics remains little applied in clinical practice for various reasons discussed in the chapter. Some perspectives are proposed and may open new horizons for clinical phonetics. Laryngeal pathologies have also addressed questions to the linguistic functioning and the phonological representation of language units, in particular with regard to the voicing feature, which is the basis of a basic and almost universal lexical contrast in the languages of the world.Motor disturbances whose symptoms on speech are grouped under the term dysarthria have also been the object of important studies at the laboratory, particularly in the context of Parkinson’s disease. These studies have contributed to the pathophysiological model of the disease by measuring various parameters of speech in the context of monitoring the disease. For example, the therapeutic effects (drug or electrophysiological) were studied via acoustic and physiological (aerodynamic) instrumental analyses. The prosodic dimension was also given an important place. This work has allowed us to highlight the characteristics of the speech of Parkinson’s patients by integrating the interactions between the pathological disorders and the linguistic structure at different levels of organization.The measurement of speech intelligibility, which is a recurrent theme in the laboratory’s research, as developed strongly and has been integrated into a clinical perspective, first with the work on Parkinson’s disease, then in the context of the after-effects of cancers of the oral cavity and oropharynx. Biases related to speech perception have led to various alternatives to intelligibility test batteries allowing to propose linguistically justified solutions adapted to clinical practice. They have also made it possible to study more precisely the articulation between the various perceptual levels involved in decoding and understanding speech.More recently, questions about the planning of speech production have emerged in the laboratory. Speech pathology and clinical phonetics provide a framework for testing these questions. Research comparing healthy subjects vs. those with cognitive deficits related to multiple sclerosis is being conducted at LPL to explore how cognitive constraints influence speech parameters of planning. Finally, we think that an epistemological and multidisciplinary challenge is now facing clinical phonetics. Clinicians and phoneticians have learned to research and work together on complex problems that have a fundamental research issue but also a societal and public health issue. The challenge is therefore to promote interaction and understanding of the issues that move these two communities. Phoneticians must be able to propose fields of application of their knowledge adapted to the real and practical problems of clinicians; and conversely, clinicians must be able to better propose observations that question and nourish reflections on the models of production, perception and understanding of speech and language.

We examined the effect of linguistic factors on the perceptual identification of intervocalic consonants produced by speakers with Parkinson's Diseases (PD). To neutralize the effect of preceding and following contexts, all the intervocalic consonants were excised with half the preceding and following vowels.We recorded 10 PD and 10 healthy speakers reading a text. An average of 114 VCV sequences per speaker was obtained. In total, our corpus consisted of 2280 stimuli. For the perception test, 20 adults native speakers of French were instructed that they would be presented utterances produced by different speakers and that they were to identify the sequences and write what they heard. No information was given on the sequence type (VCV).The reported consonant was examined in relation to the intended consonant; the score of distorsion was the number of phonetic features differing from the prototypical consonant. The results were examined as a function of the following/or preceding linguistic factors: consonant nature, oral/nasal vocalic context, class of word (function or content) and prosodic position within sentences.Consonant imprecision was confirmed in the speech of PD speakers. Two groups of patients were observed: the former with a low degree of dysarthria severity and scores of consonant identification close to that of healthy speakers; the latter with a high degree of dysarthria severity and a low identification score.Linguistic factors were shown to affect consonant production and perception. In both normal and PD speech, consonants had more features identified when they belonged to content words, word-initial syllables or final-phrase syllables. This suggests that in Parkinson's disease speech disorders relate to motor control and not to a loss of the linguistic knowledge.

Les patients atteints de la maladie de Parkinson (MDP) presentent generalement des deficits dans la production de la parole. Nous avons examine l’identification perceptive des consonnes intervocaliques produites par 10 locuteurs avec MDP et 10 locuteurs sains en lecture de texte. Pour neutraliser le contenu semantique, toutes les consonnes intervocaliques ont ete isolees avec la moitie des voyelles precedente et suivante. 20 adultes natifs francophones ont ete charges de transcrire les sequences du corpus. La consonne rapportee a ete examinee par rapport a la consonne prototypique; le score de distorsion est le nombre de traits phonetiques differents par rapport a la consonne prototypique. Les resultats ont ete examines en fonction des facteurs linguistiques suivants: nature de la consonne, contexte vocalique oral / nasal, classe de mot (fonction ou contenu) et position dans les syntagmes. L’imprecision de la consonne a ete confirmee dans la parole des locuteurs MDP. MOTS-CLES : perception, dysarthrie parkinsonienne, phonetique clinique, traits phonetiques

Cette etude porte sur l'intensite relative des consonnes intervocaliques produites par dix personnes souffrant de la maladie de Parkinson et traitees par stimulation subthalamique profonde (STN). L'objectif est double :1) examiner la maniere dont la maladie de Parkinson affecte l'intensite des consonnes du francais, l'imprecision des consonnes etant l'une des caracteristiques de la dysarthrie parkinsonienne et 2) verifier l'impact de la STN sur la parole, ce traitement chirurgical ayant des effets variables sur la parole. Le corpus est un extrait de la chevre de Monsieur Seguin lu a voix haute par dix malades sevres de L-dopa pour la nuit mais sous STN active et 30 mn plus tard avec STN arretee et par dix lecteurs referents. La distance au microphone (AKG) est constante pendant les seances d'enregistrement en chambre sourde a l'hopital d'Aix. Le signal est enregistre directement sur PC a une vitesse d'echantillonnage de 20Khz. Le signal est analyse a l'aide de PRAAT, l'etiquetage de toutes les consonnes est fait a partir des oscillogrammes et spectrogrammes presentes sur l'ecran. L'intensite moyenne de chaque consonne est obtenue automatiquement (programme de C.Gendrot) et l'intensite relative est calculee : (IMV1 + IMV2)/2 –IMC), V1 est la voyelle precedente, V2 la voyelle suivante (IM= l'intensite moyenne). Les resultats sont examines en relation avec le mode et le voisement de la consonne et avec la position dans le syntagme (consonne dans syllabe non finale/syllabe finale suivie ou non d'une pause). Les resultats montrent un effet de la maladie sur l'intensite de toutes les consonnes : l'intensite moyenne des consonnes des patients est inferieure a celle des controles Dans les deux groupes, il y a tendance a preserver les differences d'intensite en fonction du mode et du voisement. La hierarchie de valeurs obtenues pour les deux groupes est tout a fait en accord avec la hierarchie de sonorite proposee dans la litterature avec en ordre decroissant 1) occlusives non voisees, 2) constrictives non voisees, 3) occlusives voisees, 4) constrictives voisees, 5) sonorantes. L'effet de la STN est peu marque : valeurs similaires pour les occlusives et les constrictives non voisees, moindres pour les constrictives voisees et les sonorantes. La hierarchie des valeurs est la meme dans les deux conditions. L'analyse par sujet confirme ces tendances : Les differences sont significativement inferieures pour un seul patient en situation de STN active. L'intensite des consonnes varie avec la position dans le syntagme et la condition : elle est plus elevee dans la parole normale et cette difference est plus accusee pour les consonnes situees en syllabes finales prepausales. Aucune difference significative entre les deux conditions de stimulation.

The main goal of the present study was to examine the impact of Parkinson’s disease (PD) and bilateral STN stimulation on prosodic aspects of speech. This was accomplished by comparing temporal variables and F0 in the speech produced by ten patients in the “Off” and “On” conditions and ten healthy controls. Several tendencies emerged. Concerning temporal variables, there was no significant impact on articulation rate, pause ratio and pause time in the stim-off group. Furthermore, there was a strong congruence between pause pattern and syntactic structure which suggests that the syntactic function of prosody is preserved in PD speech. In contrast, the analysis of F0 revealed significant differences between controls and stim-off patients. Concerning bilateral STN stimulation, there were no group differences with respect to temporal variables and F0 values; however, closer examination of the data revealed individual differences in articulation rate, F0 mean, ranges and maxima.

Objectif: Dans les dysarthries cérébelleuses, la perte de la précision des mouvements articulatoires de la parole induit une dysrégulation temporelle avec un allongement irrégulier des durées contribuant globalement au ralentissement du débit de la parole. Ainsi, nous supposons que les distorsions du signal de parole sont largement influencées par le ralentissement et que la correction de ce ralentissement, par accélération du signal de parole, peut améliorer l’intelligibilité. Patientes et méthode: Deux patientes avec une dysarthrie ataxique ont été étudiées. L’intelligibilité de la parole a été évaluée subjectivement avec une échelle visuelle analogique et objectivement par la méthode des stimuli constants associée à une tâche d’identification d’un phonème cible en temps réel. L’accélération temporelle des stimuli est effectuée par l’algorithme SOLA. Un total de 144 stimuli a été créé à 3 vitesses différentes: 48 phrases à «vitesse naturelle» (sans accélération, VN), 48 phrases à «vitesse intermédiaire» (50% de l’accélération maximale, VI) et 48 phrases à «vitesse maximale» (vitesse moyenne des locuteurs témoins, VM). Les 144 phrases, dans les 3 présentations expérimentales, ont été réparties en 3 listes, chaque auditeur entendant une seule fois chaque phrase. Chaque liste est écoutée par 8 auditeurs. Les phrases sont présentées dans un ordre randomisé. Pour estimer l’effet de l’accélération, nous avons utilisé un modèle logit mixte pour le score de l’épreuve subjectif et les temps de réaction, un test de χ2 pour le nombre des erreurs. Résultats: Pour les 2 locutrices, la probabilité d’une meilleure intelligibilité à l’épreuve subjective est significativement plus grande pour la condition VI ou VM que pour la condition VN. Le passage de la condition VN à la condition VI augmente le taux de satisfaction des auditeurs quant à l’intelligibilité de 78 à 87% pour Mme B et de 46 à 63% pour Mme Z. Les erreurs sont moins fréquentes avec la compression pour Mme Z. L’effet de l’accélération n’est jamais significatif sur les temps de réaction (F2, 1024 = 2,14, p = 0,12). Conclusions: Cette étude est la première à analyser l’effet d’une accélération temporelle uniforme sur de la parole pathologique. Elle montre que chez 2 patientes présentant une dysarthrie ataxique, le niveau perçu de l’intelligibilité est amélioré.

Une premiere partie du projet est donc consacree a la mise en place et a la structuration d'une base de donnees informatisee de parole pathologique. Actuellement, celle- ci est alimentee par les enregistrements de plus de mille patients dysarthriques collectes par C. Chevrie-Muller entre 1965 et 1997. A terme, la structure de cette base de donnees, permettant un acces securise a differentes informations sur les locuteurs et les types de materiaux linguistiques, sera un outil extremement utile pour toute etude sur les dysfonctionnements de la parole et de la voix, et facilitera ainsi le controle de l'homogeneite/heterogeneite clinique des locuteurs qui est central dans ce type d'etude.

Objectives: The present study had 2 main objectives: (1) examine the effect of Parkinson’s disease (PD) on vowel and consonant duration in French read speech and (2) investigate whether the durational contrasts of consonants and vowels are maintained or compromised. Results: The data indicated that the consonant durations were shortened in Parkinsonian speech (PS), compared to control speech (CS). However, this shortening was consonant dependent: unvoiced occlusives and fricatives were significantly shortened compared to other consonant categories. All vowels were slightly longer in PS than in CS, however, the observed differences were below the level of significance. Despite significant shortening of some consonant categories, the general pattern of intrinsic duration was maintained in PS. There was slightly less agreement for vowels with the normal contrast of intrinsic durations, possibly because vowel durational contrasts are more sensitive to PD disorders. Conclusion: Most PD patients tended to maintain the intrinsic duration contrasts of both vowels and consonants, suggesting that low-level articulatory constraints operate in a similar way and with the same weight in PS and CS.

This study had two objectives. The first was to analyse the impact of Parkinson's disease (PD) on the duration of CV syllables and their components in different positions within phrases in French; the second was to examine the distribution of final lengthening (FL) on syllable sub-components. Two main tendencies emerged: (1) PD patients produced normal FL, and (2) FL influenced vowels more than consonants. These findings suggest that PD speakers had no difficulty with FL and that there is a progressive lengthening across the sub-constituents of the final syllable. More fundamentally, these results indicate that the syntactic function of prosody is intact in PD patients, at least during the early and mild stages of the disease.

The current study investigated selected acoustic characteristics of the weakening of occlusives (O's) in French Parkinsonian Speech (PS). The results confirm an increase in the reduction of O's in PS compared to control speech (CS). In PS, O's have a significantly decreased intervocalic energy level, slightly shorter realisations and a higher number of visible formants and noise; the number of burstless and omitted O's is also higher. However, weakening patterns vary between different consonants and are strongly dependent on voicing and place. Occlusive weakening, a consequence of Parksinson's disease production deficits, appears to be influenced by the inherent- articulatory characteristics of consonants.

The ensuing study examined the impact of Parkinson disease (PD) on the duration of CV syllables in different positions within phrases and the distribution of final lengthening (FL) on syllable subcomponents. Two main tendenciess emerged:1) PD patients produced normal FL and 2) FL effects can be attributed primarily to vowels. These findings suggest that PD speakers had no difficulty with FL and that there is a progressive lengthening across the subconstituents of the final syllable. More fundamentally, these results indicate that the syntactic function of prosody is intact in PD patients at least at the early and mild stages of the disease.