Impact of Vocal Effort on Respiratory and Articulatory Kinematics

Purpose: The goal of this study was to examine the effects of increases in vocal effort, without changing speech intensity, on respiratory and articulatory kinematics in young adults with typical voices. Method: A total of 10 participants completed a reading task under three speaking conditions: baseline, mild vocal effort, and maximum vocal effort. Respiratory inductance plethysmography bands around the chest and abdomen were used to estimate lung volumes during speech, and sensor coils for electromagnetic articulography were used to transduce articulatory movements, resulting in the following outcome measures: lung volume at speech initiation (LVSI) and at speech termination (LVST), articulatory kinematic vowel space (AKVS) of two points on the tongue dorsum (body and blade), and lip aperture. Results: With increases in vocal effort, and no statistical changes in speech intensity, speakers showed: (a) no statistically significant differences in LVST, (b) statistically significant increases in LVSI, (c) no statistically significant differences in AKVS measures, and (d) statistically significant reductions in lip aperture. Conclusions: Speakers with typical voices exhibited larger lung volumes at speech initiation during increases in vocal effort, paired with reduced lip displacements. To our knowledge, this is the first study to demonstrate evidence that articulatory kinematics are impacted by modulations in vocal effort. However, the mechanisms underlying vocal effort may differ between speakers with and without voice disorders. Thus, future work should examine the relationship between articulatory kinematics, respiratory kinematics, and laryngeal-level changes during vocal effort in speakers with and without voice disorders. Supplemental Material https://doi.org/10.23641/asha.17065457

Vocal size exaggeration may have contributed to the origins of vocalic complexity

Vocal tract elongation, which uniformly lowers vocal tract resonances (formant frequencies) in animal vocalizations, has evolved independently in several vertebrate groups as a means for vocalizers to exaggerate their apparent body size. Here, we propose that smaller speech-like articulatory movements that alter only individual formants can serve a similar yet less energetically costly size-exaggerating function. To test this, we examine whether uneven formant spacing alters the perceived body size of vocalizers in synthesized human vowels and animal calls. Among six synthetic vowel patterns, those characterized by the lowest first and second formant (the vowel /u/ as in ‘boot’) are consistently perceived as produced by the largest vocalizer. Crucially, lowering only one or two formants in animal-like calls also conveys the impression of a larger body size, and lowering the second and third formants simultaneously exaggerates perceived size to a similar extent as rescaling all formants. As the articulatory movements required for individual formant shifts are minor compared to full vocal tract extension, they represent a rapid and energetically efficient mechanism for acoustic size exaggeration. We suggest that, by favouring the evolution of uneven formant patterns in vocal communication, this deceptive strategy may have contributed to the origins of the phonemic diversification required for articulated speech. This article is part of the theme issue ‘Voice modulation: from origin and mechanism to social impact (Part II)’.

A single exposure to altered auditory feedback causes observable sensorimotor adaptation in speech

Sensory errors caused by perturbations to movement-related feedback induce two types of behavioral changes that oppose the perturbation: rapid compensation within a movement, as well as longer-term adaptation of subsequent movements. Although adaptation is hypothesized to occur whenever a sensory error is perceived (including after a single exposure to altered feedback), adaptation of articulatory movements in speech has only been observed after repetitive exposure to auditory perturbations, questioning both current theories of speech sensorimotor adaptation as well as the universality of more general theories of adaptation. Thus, positive evidence for the hypothesized single-exposure or 'one-shot' learning would provide critical support for current theories of speech sensorimotor learning and control and align adaptation in speech more closely with other motor domains. We measured one-shot learning in a large dataset in which participants were exposed to intermittent, unpredictable auditory perturbations to their vowel formants (the resonant frequencies of the vocal tract that distinguish between different vowels). On each trial, participants spoke a word out loud while their first formant was shifted up, shifted down, or remained unshifted. We examined whether the perturbation on a given trial affected speech on the subsequent, unperturbed trial. We found that participants adjusted their first formant in the opposite direction of the preceding shift, demonstrating that learning occurs even after a single auditory perturbation as predicted by current theories of sensorimotor adaptation. While adaptation and the preceding compensation responses were correlated, this was largely due to differences across individuals rather than within-participant variation from trial to trial. These findings are more consistent with theories that hypothesize adaptation is driven directly by updates to internal control models than those that suggest adaptation results from incorporation of feedback responses from previous productions.

PHONETIC AND PSYCHOLINGUISTIC APPROACH TO CONSIDERATION OF SPEECH PATHOLOGY "STUTTER"

Постановка задачи. В статье исследуется явление заикания с фонетической и психолингвистической точки зрения. Речевой ритм сравнительно недавно стал пристальным объектом исследования в фонетике и речеведении. Актуальные данные этих исследований не проникли в значительной степени в область логопедии. Рассматривается речевой ритм с точки зрения физиологии, нейролингвистики, психолингвистики. Данные о первичном усвоении параметров речевого ритма родного языка создают с точки зрения фонетики представление о «вписывании» артикуляционных движений в ритмическую матрицу слова и фразы. Нарушения же в реализации этой матрицы дают возможность проследить поведение артикуляционных комплексов при сбое ритмической основы. В работе описывается экспериментальное исследование нарушения речевого ритма как причина речевых ошибок (патологий). Результаты и выводы. Вербальные и невербальные компоненты используются при ритмизации речевой деятельности. Используются коррекционные приёмы, в результате которых возникает пролонгированное эмоционально положительное состояние и начинается произвольное использование новой речевой программы. Данное состояние вводится в процессе аутотренинга. Эмоционально комфортное состояние при использовании ритмизированной речи закрепляется на функциональных речевых тренировках. Речь идет об усилении речевого ритма родного языка без искажения его параметров. Problem statement. The article examines the phenomenon of stuttering from a phonetic and psycholinguistic point of view. Speech rhythm has recently become a close object of research in phonetics and speech. The actual data from these studies have not penetrated significantly into the field of speech therapy. The speech rhythm is considered from the point of view of physiology, neurolinguistics, psycholinguistics. Data on the primary assimilation of the parameters of the speech rhythm of the native language from the point of view of phonetics create the idea of "inscribing" articulatory movements into the rhythmic matrix of words and phrases. Violations in the implementation of this matrix make it possible to trace the behavior of articulatory complexes when the rhythmic basis fails. The paper describes an experimental study of speech rhythm disturbance as the cause of speech errors (pathologies). Results and conclusion. Verbal and non-verbal components are used to rhythmize speech activity. Corrective techniques are used, because of which a prolonged emotionally positive state arises, and the voluntary use of a new speech program begins. This state is introduced in the process of auto-training. Emotionally comfortable state when using rhythmized speech is fixed on functional speech training. We are talking about strengthening the speech rhythm of the native language without distorting its parameters.

The Effects of Symptom Onset Location on Automatic Amyotrophic Lateral Sclerosis Detection Using the Correlation Structure of Articulatory Movements

Purpose Kinematic measurements of speech have demonstrated some success in automatic detection of early symptoms of amyotrophic lateral sclerosis (ALS). In this study, we examined how the region of symptom onset (bulbar vs. spinal) affects the ability of data-driven models to detect ALS. Method We used a correlation structure of articulatory movements combined with a machine learning model (i.e., artificial neural network) to detect differences between people with ALS and healthy controls. The performance of this system was evaluated separately for participants with bulbar onset and spinal onset to examine how region of onset affects classification performance. We then performed a regression analysis to examine how different severity measures and region of onset affects model performance. Results The proposed model was significantly more accurate in classifying the bulbar-onset participants, achieving an area under the curve of 0.809 relative to the 0.674 achieved for spinal-onset participants. The regression analysis, however, found that differences in classifier performance across participants were better explained by their speech performance (intelligible speaking rate), and no significant differences were observed based on region of onset when intelligible speaking rate was accounted for. Conclusions Although we found a significant difference in the model's ability to detect ALS depending on the region of onset, this disparity can be primarily explained by observable differences in speech motor symptoms. Thus, when the severity of speech symptoms (e.g., intelligible speaking rate) was accounted for, symptom onset location did not affect the proposed computational model's ability to detect ALS.

Unilateral opercular lesion mimicking opercular syndrome

Introduction: Foix-Chavany-Marie syndrome, also known as opercular syndrome, consists of voluntary orofacial muscle paralysis due to bilateral lesions in the anterior frontotemporal operculum. Classically, there is an automatic-voluntary dissociation, with impairment of speech and chewing. We present a case of a patient who had a similar presentation to opercular syndrome, secondary to unilateral ischemic lesion in the right frontal operculum. Case report: A 55-year-old, right-handed, black woman with history of arterial hypertension was admitted to the emergency department presenting left-sided weakness and inability to speak, noticed upon waking. When approached, the patient was unable to produce sounds but managed to communicate through articulatory movements of lips and was able to write correctly without signs of aphasia. On examination, there was left central facial paralysis, marked reduction in mouth opening amplitude, inability to perform tongue protrusion without lateral deviation and bilateral reduction in palate elevation. There was also a mild left brachial- predominant hemiparesis (grade IV). A cranial computed tomography scan exhibited an acute ischemic lesion of the right frontal opercular region, without other lesions in the homologous contralateral area. The etiological investigation with electrocardiogram, echocardiogram and carotid doppler ultrasound had no significant abnormalities. Conclusion: We reported a case of a patient presenting with aphonia and bulbar musculature paresis due to a right unilateral frontal opercular lesion, mimicking the opercular syndrome presentation.

Microstate ERP Analyses to Pinpoint the Articulatory Onset in Speech Production

The use of electroencephalography (EEG) to study overt speech production has increased substantially in the past 15 years and the alignment of evoked potential (ERPs) on the response onset has become an extremely useful method to target “latest” stages of speech production. Yet, response-locked ERPs raise a methodological issue: on which event should the point of alignment be placed? Response-locked ERPs are usually aligned to the vocal (acoustic) onset, although it is well known that articulatory movements may start up to a hundred milliseconds prior to the acoustic onset and that this “articulatory onset to acoustic onset interval” (AAI) depends on the phoneme properties. Given the previously reported difficulties to measure the AAI, the purpose of this study was to determine if the AAI could be reliably detected with EEG-microstates. High-density EEG was recorded during delayed speech production of monosyllabic pseudowords with four different onset consonants. Whereas the acoustic response onsets varied depending on the onset consonant, the response-locked spatiotemporal EEG analysis revealed a clear asynchrony of the same sequence of microstates across onset consonants. A specific microstate, the latest observed in the ERPs locked to the vocal onset, presented longer duration for phonemes with longer acoustic response onsets. Converging evidences seemed to confirm that this microstate may be related to the articulatory onset of motor execution: its scalp topography corresponded to those previously associated with muscle activity and source localization highlighted the involvement of motor areas. Finally, the analyses on the duration of such microstate in single trials further fit with the AAI intervals for specific phonemes reported in previous studies. These results thus suggest that a particular ERP-microstate is a reliable index of articulation onset and of the AAI.