Search

In Parkinson’s disease (PD), the effects of both Ldopa and subthalamic deep brain stimulation (STN-DBS) are known to change cost-valuation. However, this was mostly studied through reward-effort task involving distal movements, while axial effort, less responsive to treatments, have been barely studied. Thus, our objective was to compare the influence of both Ldopa and STN-DBS on cost-valuation between two efforts modalities: vowel production (as an example of axial movement) and hand squeezing (as an example of distal movement). Twelve PD patients were recruited to participate in this study. The task consisted in deciding whether to accept or reject trials based on a reward-effort trade-off. Participants performed two blocks with hand squeezing, and two with vowel production, in the four treatment conditions (LdopaOn/Off; STN-DBS On/Off). We found that STN-DBS changed the ratio difference between hand and phonation efforts. Vowel production effort was estimated easier to perform with STN-DBS alone, and harder when associated with Ldopa. The difference between hand and phonation efforts was correlated with quality of life in Off/Off and On Ldopa alone conditions, and with impulsive assessment On STN-DBS alone. We highlighted that STN-DBS could introduce an imbalance between the actual motor impairments and their subjective costs. With this finding, we also suggest paying particular attention to the different treatment effects that should be expected for axial and distal movement dysfunctions.

Resume Objectifs Elaborer un protocole experimental permettant d’etudier l’effort vocal genere par l’introduction d’obstacles a la communication et etudier la relation entre celui-ci et certains traits de personnalite. Materiel et methodes Le protocole experimental consistait en un jeu interactif dans lequel le sujet devait donner au premier examinateur des consignes pour qu’il realise differentes positions (situation de communication semi-dirigee). La situation controle etait realisee sans contrainte de communication puis il etait introduit une contrainte de distance (augmentation de la distance interpersonnelle) et une contrainte temporelle (generation d’un stress de performance en placant le sujet en competition avec les autres). Les parametres vocaux etudies comprenaient l’intensite vocale et la frequence fondamentale en milieu de voyelle, sur 3 phonemes cibles. Chaque sujet etait soumis au test de personnalite NEO FFI-R. Resultats L’etude a porte sur 41 femmes âgees de 18 a 52 ans. L’intensite et la frequence fondamentale augmentaient significativement lors de l’introduction des contraintes (p Conclusions Ce protocole ecologique permet d’etudier l’impact d’obstacles physiques mais aussi emotionnels. Le lien entre effort vocal et traits de personnalite n’a pas ete demontre. Une etude avec des effectifs superieurs serait necessaire afin de caracteriser le continuum entre effort vocal et forcage vocal pour une meilleure prise en charge orthophonique des dysphonies dysfonctionnelles.

Facilitated communication (FC) belongs to augmentative and alternative methods of communication. Currently, FC is very rarely and unofficially used with people suffering from verbal/communicative disorders or neurodevelopmental disorders such as intellectual deficiency or autism spectrum disorder (ASD). FC consists of physical support exerted by a facilitator at the hand/wrist/forearm/elbow of a patient/participant, aimed at helping him/her to point at pictures/words, and sometimes to type letters/words on a keyboard. Given most of (but not all) validation studies using control procedures failed to confirm that ASD participants themselves were authoring the messages via FC, this method has been massively disputed and rejected. However, firm and definitive conclusions for/against the validity of FC requires more robust demonstrations, particularly when considering the motor participation of both protagonists. We present here a case report investigating the motor contribution of both protagonists during a typing process using the non-invasive technique of accelerometry. A 17-year-old boy diagnosed with congenital deafness, ASD, and developmental delay, and his facilitator, were equipped with small accelerometers fixed on their index finger, aimed at transforming index acceleration along the three spatial axes into electric signals. Typing on a PC keyboard was performed under three support conditions: hand support, forearm support, elbow support, plus a solo-typing condition. Accelerometric signals and video data were recorded during four FC sessions. We measured and compared the typing speed, the number/percentage of acceleration peaks produced by the participant or by the facilitator first, and those of “signal under detection threshold” in the facilitator, the time offset between acceleration peaks of both protagonists, and the difference of the amount of acceleration between them, across the different support conditions. Results indicate that in the hand support, most of the time, acceleration motions of the participant's index finger preceded those of the facilitator's index finger. Then, the more distal the physical support (i.e., farer from the participant's hand), the slower the speed of typing, the higher the percentage of “signal under detection threshold” in the facilitator, the bigger the motor contribution from the participant. Altogether, in all the support conditions, the participant's authorship or, at least, co-authorship on the messages seems warranted. Finally, accelerometry seems relevant to objectivize authorship or co-authorship in FC and delineate various forms of FC.

International audience; Objective. To analyze the range of values of the contact pressure between the membranous vocal folds with Reinke’s edema and to compare it to those observed in the absence of such a lesion.Methods. Two human larynges were separately tested on the experimental bench, one of them with a bilateral loose swelling of the vocal folds. Once in a glottal prephonatory configuration, airflow was increased until achievement of self-sustained oscillations while recording aerodynamic, acoustic, electroglottographic data, and contact pressure between the folds.Results. We observed well-documented variations in acoustical parameters, as the decrease of the fundamental frequency and the increase of the phonation threshold pressure. The results of the study also point to a significant increase in the amplitude of the contact pressure in presence of the Reinke’s edema, and a lower degree of harmonicity of the produced sounds.Conclusion. This is the first report of ex vivo study of a larynx with Reinke’s edema. It highlights the increase in the contact pressure during phonation, which possibly contributes to sustain the lesion once it appeared.

Preclinical studies of psychiatric disorders use animal models to investigate the impact of environmental factors or genetic mutations on complex traits such as decision-making and social interactions. Here, we introduce a method for the real-time analysis of the behaviour of mice housed in groups of up to four over several days and in enriched environments. The method combines computer vision through a depth-sensing infrared camera, machine learning for animal and posture identification, and radio-frequency identification to monitor the quality of mouse tracking. It tracks multiple mice accurately, extracts a list of behavioural traits of both individuals and the groups of mice, and provides a phenotypic profile for each animal. We used the method to study the impact of Shank2 and Shank3 gene mutations—mutations that are associated with autism—on mouse behaviour. Characterization and integration of data from the behavioural profiles of Shank2 and Shank3 mutant female mice revealed their distinctive activity levels and involvement in complex social interactions. A method that combines a depth-sensing camera and machine learning can track the movements of up to four mice in real time and for several days, extracting both individual and group behavioural traits.

International audience; Objectives To develop an experimental protocol to study the vocal effort generated by introducing barriers to communication, and its relationship with certain personality traits. Material and methods The experimental protocol consisted of an interactive game in which the subject gave an investigator instructions to adopt various body positions (semi-directed communication situation). The Control situation included no constraints on communication. Then a Distance Constraint (increased distance between subject and investigator) and a Time Constraint (generation of performance stress by putting the subject in competition with others) were introduced. The vocal parameters studied comprised vocal intensity and fundamental frequency in the middle of the vowel of 3 target phonemes. Subjects also took the NEO FFI-R personality test. Results The study included 41 women aged between 18 and 52 years. Vocal intensity and fundamental frequency increased significantly with the introduction of the constraints ( P < 0.05), intensity passing from 75.5 dB to 81.8 dB and frequency from 249.4 Hz to 335.8 Hz. No correlations were found between these changes and results for the various personality traits. Conclusions This ecological protocol enables the impact of both physical and emotional obstacles to communication to be studied. No correlations between vocal effort and personality traits emerged. A larger-scale study would be necessary to analyze the continuum between vocal effort and vocal forcing, to improve speech therapy for dysfunctional dysphonia.

L’objectif de ce travail est d’etudier les evenements physiologiques et articulatoires ayant lieu durant les pauses silencieuses dans differents types de discours. Pour ce faire, un enregistrement audio a ete realise a partir d’une locutrice qui avait pour tâche de lire un texte a deux reprises et de decrire une image. Les donnees acoustiques etaient synchronisees avec un articulographe electromagnetique (EMA) afin d’observer les eventuels deplacements des articulateurs dans la cavite buccale durant les pauses et avec une ceinture respiratoire qui permettait de deceler les prises de souffle. Ce dispositif a permis d’observer un certain nombre de mouvements durant les pauses, qui sont notamment dus a la retention des derniers sons de la sequence sonore precedant la pause et/ou a l’anticipation des sons a venir.

International audience; Objective and Hypothesis: Vocal effort in loud voice is produced with increased subglottal pressure during vowels and increased supraglottal pressure during consonants. In the paper, our main objective is to check whether it was supported by a parallel increase in the airflow resistance of the laryngeal articulator and of the supralaryngeal articulator, here the lips. Study Design and Method: For this comparison, our choice fell on the fricative consonants, as their production allows perfectly synchronous air pressure and airflow measurements. Also, the calculation of the real instantaneous aerodynamic resistance is possible with fricatives-as it is with vowels-whereas it is not possible with plosives. The present feasibility study on a healthy subject is based on direct subglottal and intraoral pressures and airflow measured for /f/ or /v/ and from the contiguous vowel produced in VCVCV non sense words at different levels of intensity. Results and Conclusion: The results support that the airflow resistances at the lips and that at the larynx are quite parallel. The airflow resistance at the lips during labial fricative production could provide a good picture of the laryngeal resistance during the production of continuous speech. This suggests clinical applications using both non invasive inferred measurements of subglottal pressure variation and direct non inferred airflow measurements from more natural speech production tasks.

International audience; Introduction: The objective was to study the behavior of the larynx during shouted voice production,when the larynx is exposed to extremely high subglottic pressure. Materials and methods: The study involved electroglottographic, acoustic, and aerodynamic analyses of shouts produced at maximum effort by three male participants. Results and discussion: Under a normal speaking voice, the voice sound pressure level (SPL) is proportional to the subglottic pressure. However, when the subglottic pressure reached high levels, the voice SPL reached a maximum value and then decreased as subglottic pressure increased further. Furthermore, the electroglottographic signal sometimes lost its periodicity during the shout, suggesting irregular vocal fold vibration.

Place: Germany; INTRODUCTION: The objective of this paper was to identify the determining factors of the glottal prephonatory configuration from the point of view of the resulting muscular actions (i.e., arytenoids adduction, membranous vocal fold adduction, and tension). MATERIALS AND METHODS: 21 human non-embalmed excised larynges (12 females and 9 males) were studied. Experiment A (11 larynges) studied four conditions of adduction of the vocal folds and arytenoids. Experiment B (10 larynges) studied the effect of cricothyroid approximation on the vocal fold length and the cricothyroid angle. RESULTS: Experiment A: The mean glottal area significantly decreased from 41.2 mm(2) mean with no adduction, to 10.2 mm(2) mean with arytenoid adduction, to 9.2 mm(2) with membranous vocal fold adduction, and down to 1.1 mm(2) with the combination of arytenoid and membranous adduction. The effect of the task was statistically significant. Experiment B: The length of vocal folds increased from 13.61 mm median to 14.48 mm median, and the cricothyroid angle decreased of 10.05 median along with cricothyroid approximation. DISCUSSION: The results of experiment A emphasize the sub-division of adductor intrinsic muscles in arytenoids adductors (i.e., LCA and IA), and membranous vocal fold adductor (i.e., TA). The results of experiment B quantify the effect of cricothyroid approximation on the vocal folds length. The implications of these results can be useful in both clinical practice and experimental studies.

International audience; This study builds on a specific characteristic of letters of the Roman alphabet-namely, that each letter name is associated with two visual formats, corresponding to their uppercase and lowercase versions. Participants had to read aloud the names of single letters, and event-related potentials (ERPs) for six pairs of visually dissimilar upper- and lowercase letters were recorded. Assuming that the end product of processing is the same for upper- and lowercase letters sharing the same vocal response, ERPs were compared backward, starting from the onset of articulatory responses, and the first significant divergence was observed 120 ms before response onset. Given that naming responses were produced at around 414 ms, on average, these results suggest that letter processing is influenced by visual information until 294 ms after stimulus onset. This therefore provides new empirical evidence regarding the time course and interactive nature of visual letter perception processes.

Since the 19th century, it has been known that response latencies are longer for naming pictures than for reading words aloud. While several interpretations have been proposed, a common general assumption is that this difference stems from cognitive word-selection processes and not from articulatory processes. Here we show that, contrary to this widely accepted view, articulatory processes are also affected by the task performed. To demonstrate this, we used a procedure that to our knowledge had never been used in research on language processing: response-latency fractionating. Along with vocal onsets, we recorded the electromyographic (EMG) activity of facial muscles while participants named pictures or read words aloud. On the basis of these measures, we were able to fractionate the verbal response latencies into two types of time intervals: premotor times (from stimulus presentation to EMG onset), mostly reflecting cognitive processes, and motor times (from EMG onset to vocal onset), related to motor execution processes. We showed that premotor and motor times are both longer in picture naming than in reading, although than in reading, although articulation is already initiated in the latter measure. Future studies based on this new approach should bring valuable clues for a better understanding of the relation between the cognitive and motor processes involved in speech production.

In a previous article, (Ries, Legou, Burle, Alario, & Malfait, 2012), we reported that articulatory processes contribute to the well-established finding that response latencies are longer for picture naming than for word reading. We based this conclusion on the observation that picture naming, as compared with word reading, lengthened not only the interval between stimulus onset and the initiation of lip muscle activation (premotor time), but also the interval between lip muscle activation and vocal response onset (motor time). However, on the basis of our subsequent work in this area, we believe that our original definition of premotor time (and, consequently, of motor time) was suboptimal. On a sizable number of trials, this led to the detection of lip muscle activation (as inferred from surface EMG) that was apparently unrelated to the articulation of the vocal response. Therefore, we believe it is preferable to operationalize premotor time as the interval between stimulus onset and the muscle activation that occurred closest in time to vocal response onset. After reestimating premotor times according to this new definition, we no longer found an effect of our task contrast on the motor time interval. The present article explains the caveats regarding our previous analysis.

International audience; Abstract The glottal geometry is a key factor in the aerosol delivery efficiency for treatment of lung diseases. However, while glottal vibrations were extensively studied during human phonation, the realistic glottal motion during breathing is poorly understood. Therefore, most current studies assume an idealized steady glottis in the context of respiratory dynamics, and thus neglect the flow unsteadiness related to this motion. This is particularly important to assess the aerosol transport mechanisms in upper airways. This article presents a clinical study conducted on 20 volunteers, to examine the realistic glottal motion during several breathing tasks. Nasofibroscopy was used to investigate the glottal geometrical variations simultaneously with accurate airflow rate measurements. In total, 144 breathing sequences of 30s were recorded. Regarding the whole database, two cases of glottal time-variations were found: “static” or “dynamic” ones. Typically, the peak value of glottal area during slow breathing narrowed from 217 ± 54 mm2 (mean ± STD) during inspiration, to 178 ± 35 mm2 during expiration. Considering flow unsteadiness, it is shown that the harmonic approximation of the airflow rate underevaluates the inertial effects as compared to realistic patterns, especially at the onset of the breathing cycle. These measurements provide input data to conduct realistic numerical simulations of laryngeal airflow and particle deposition.

To describe the mental architecture between stimulus and response, cognitive models often divide the stimulus-response (SR) interval into stages or modules. Predictions derived from such models are typically tested by focusing on the moment of response emission, through the analysis of response time (RT) distributions. To go beyond the single response event, we recently proposed a method to fractionate verbal RTs into two physiologically defined intervals that are assumed to reflect different processing stages. The analysis of the durations of these intervals can be used to study the interaction between cognitive and motor processing during speech production. Our method is inspired by studies on decision making that used manual responses, in which RTs were fractionated into a premotor time (PMT), assumed to reflect cognitive processing, and a motor time (MT), assumed to reflect motor processing. In these studies, surface EMG activity was recorded from participants' response fingers. EMG onsets, reflecting the initiation of a motor response, were used as the point of fractionation. We adapted this method to speech-production research by measuring verbal responses in combination with EMG activity from facial muscles involved in articulation. However, in contrast to button-press tasks, the complex task of producing speech often resulted in multiple EMG bursts within the SR interval. This observation forced us to decide how to operationalize the point of fractionation: as the first EMG burst after stimulus onset (the stimulus-locked approach), or as the EMG burst that is coupled to the vocal response (the response-locked approach). The point of fractionation has direct consequences on how much of the overall task effect is captured by either interval. Therefore, the purpose of the current paper was to compare both onset-detection procedures in order to make an informed decision about which of the two is preferable. We concluded in favour or the response-locked approach.

The aim of this study was to rank vocal exercises using semi-occluded vocal tracts (SOVT) as a function of their effect on subglottal pressure (SGP) and on transglottal pressure (TGP). Direct measurements were performed in two healthy females. The correct realization of vocal exercises was controlled by maintaining a constant airflow at the phonation onset. TGP varied from 1.8 to 5.9 hPa among SOVT, in the same range as phonation threshold pressure values. SGP varied among subjects from 19.4 for 2-mm straw to 3.2 hPa for closed vowel. SOVT could be ranked in voice rehabilitation from the greatest to the smallest effects on SGP as following: 1) 2-mm straw; 2) 5-mm straw and fricative /v/; 3) 8-mm straw and nasals /m/ and /n/; 4) vowel /i/.

International audience; Introduction: Postural aspects of vocal effort are unusually described in the literature whereas they are extensively managed in speech therapy. Objectives: This study aims to determine whether body movement is a side-effect of vocal effort or an integrant part of global communication effort behaviour. The answer to this question is mainly based on the correlations between the movement and the phonation.Design: This experimental study involved healthy subjects. They had to communicate to a listener during exposure to three situations where the environmental obstacles were increasing.Results: Vocal parameters such as sound pressure level, fundamental frequency, closed quotient and words duration all increased with increasing difficulty of communication (ie. increasing vocal effort). All body segments movement increased their amplitude and duration with increasing vocal effort. Vocal and kinematic characteristics were significantly correlated.Conclusion: The close correlation of movement and vocal production during vocal effort definitely excludes that the movement is a consequence of the latter. Posture and voice are coordinated in the action of communication and each body segment seems to play a different role in the vocal effort behaviour.

National audience; The aim of this study was (i) to characterise the glottal dynamics during human breathing in vivo using laryngofiberscopy and synchronised airflow recordings and (ii) to quantify the effects of a mobile glottis and unsteady flow conditions on laryngeal jet-flow dynamics using CFD modelling. The in vivo study showed that the glottis can be extremely variable during breathing and hence influence airflow characteristics. A glottal area widening was quantified during inspiration, with a typical ratio of 3:1 as compared to expiration. Airflow rate variations differ from harmonic signal during eupnea as well as tachypnea. The correlation between flow-rate and glottal area will be discussed and compared to previous clinical investigations. Preliminary 2D CFD simulations of the glottal jet were carried out based on the measured flow-rate and glottal changes during eupnea. Impact of unsteady flow conditions on the jet development is demonstrated.