Acoustic characteristics of Italian Parkinsonian speech: a study on early-stage patients

Parkinson’s Disease (PD) is a neurological illness which also has effects on speech production, resulting in segmental and suprasegmental abnormalities. The aim of the current study is to test the validity of two acoustic parameters - %V and VtoV - for the detection of rhythmical variation in early-stage PD speech, in comparison to healthy speech. 40 Italian native speakers were enrolled in the research, 20 early-stage PD subjects and 20 neurologically healthy and matched controls, and a corpus of read speech was collected. The results of voice analysis confirmed an alteration of vocalic duration and %V in PD productions. In particular, %V could be a reliable cue for PD speech characterization, even at the very early onset of the disease

Changes in speech intelligibility and acoustic distinctiveness along a speech rate continuum in Parkinson’s disease

Asking a person to speak slowly is a common technique in speech therapy for people with Parkinson’s disease (PD). Slowed speaking rates are thought to bring about changes in speech production that make it easier for people with speech impairments associated with PD to be understood, but this is not always the case. Furthermore, research suggests that using faster speech does not necessarily lead to decreases in speech intelligibility for some people with PD. Most studies of rate modification in PD have only included one or two rate adjustments to investigate the relationship between speech rate, intelligibility, and acoustic aspects of speech production. The present study adds to this literature and expands it by eliciting a broader range of speech rates than has previously been studied in order to provide a comprehensive description of changes along such a continuum. Two groups of people with PD and documented speech changes participated: 22 receiving standard pharmaceutical intervention, and 12 who additionally had undergone deep brain stimulation surgery (DBS), a common surgical treatment for PD. DBS is often associated with further speech impairment, but it is unknown to what extent these individuals may benefit from speech rate adjustments. Younger and older healthy control groups were also included. All participants were asked to modify their speech rate along a seven-step continuum from very slow to very fast while reading words, sentences, and responding to prompts. Naïve listeners later heard these speech samples and were asked to either transcribe or rate what they heard. Results indicated different patterns of speech changes across groups, rates, and tasks. Sentence reading and conversational speech were rated as being more intelligible at slow rates, and less intelligible at fast rates. All modified rates were found to negatively impact speech sound identification during a novel carrier phrase task. Slower speech was overall associated with greater acoustic contrast and variability, lower intensity, and higher voice quality. Differences in acoustic speech adjustments across the groups and speech rates emerged, however, in particular for the DBS group. Findings pointed to a complex relationship between speech rate modifications, acoustic distinctiveness, and intelligibility

Impact de la prise en charge thérapeutique sur les propriétés acoustiques des voyelles dans la maladie de Parkinson

Introduction : La maladie de Parkinson (MP) est généralement considérée comme une maladie dégénérative multisystémique. En parallèle aux symptômes moteurs principaux de la maladie tels que les tremblements, la rigidité et la bradykinésie, plus de 90% des personnes atteintes de la MP développent des troubles de la parole. La phonation, la prosodie et l’articulation sont les trois principales composantes de la parole altérées dans la MP. Ces changements sont regroupés sous le terme « dysarthrie hypokinétique ». La production des voyelles, un élément important pour l’intelligibilité de la parole, est fréquemment atteinte dans la MP. Il existe actuellement plusieurs interventions thérapeutiques visant à réduire les symptômes moteurs de la MP, tels que le traitement pharmacologique et le traitement chirurgical. Des traitements orthophoniques sont également parfois offerts aux patients dans le but de réduire les troubles de la communication secondaires à la dysarthrie. Par contre, l’impact de ces différentes interventions thérapeutiques sur la production des voyelles dans la MP est toujours largement inconnu. Objectifs : Étudier l’impact du traitement pharmacologique (levodopa), chirurgical (stimulation cérébrale profonde du noyau sous-thalamique, SCP-NST) et orthophonique (Lee-Silverman Voice Treatment, LSVT®) sur les propriétés acoustiques des voyelles dans la MP. Résultats : En ce qui concerne l’impact de la levodopa, la prise quotidienne de dose élevée peut mener à une altération de l’articulation des voyelles. À dose réduite, cet effet secondaire de la médication semble disparaitre. En ce qui concerne l’impact de la SCP-NST, l’intervention chirurgicale elle-même peut altérer l’articulation des voyelles, alors que les stimulations électriques peuvent quant à elles l’améliorer. De plus, la SCP-NST peut améliorer indirectement l’articulation des voyelles via réduction de la dose quotidienne de levodopa requise pour adresser les symptômes moteurs de la maladie, réduction secondaire à l’intervention. En ce qui concerne l’impact du LSVT®, ce traitement peut améliorer l’articulation et la coarticulation des voyelles. Conclusions : La production des voyelles est sensible aux différentes interventions thérapeutiques offertes aux personnes atteintes de la MP. La production de la parole et, spécifiquement, l’articulation et la coarticulation des voyelles, devrait faire partie intégrante de l’évaluation des patients lors du choix et de l’optimisation des interventions thérapeutiques qui leur sont offerts.Background: Parkinson’s disease (PD) is commonly viewed as a multi-systemic degenerative disorder. Alongside motor symptoms such as tremor, muscle rigidity and bradykinesia, up to 90% of people with PD develop speech disorders over the course of the disease. Phonation, prosody and articulation are the three main speech components altered in PD. These changes are grouped under the term “hypokinetic dysarthria”. Vowel production, an important aspect of speech for intelligibility, is commonly altered in PD. Various pharmacological and surgical interventions are now available to help manage the different motor symptoms of patients with PD. Speech therapies are also sometimes offered to patients to help manage communication disorders related to dysarthria. The impact of these therapeutic interventions on vowel production is, however, still largely unknown. Purpose: To investigate the impact of pharmacological (levodopa), chirurgical (deep-brain stimulation of the subthalamic nucleus, STN-DBS) and speech (Lee-Silverman Voice Treatment, LSVT®) interventions on the acoustic proprieties of vowels in PD. Results: Regarding the impact of levodopa, high daily doses may lead to vowel articulation impairment. At reduced doses, this adverse effect seems to disappear. As for the impact of STN-DBS, the surgical intervention itself may lead directly to vowel articulation impairment, while the electrical stimulations themselves may improve it. Also, STN-DBS may indirectly improve vowel articulation via the reduction of the daily levodopa dose required to manage the symptoms of PD following the intervention. Regarding the impact of LSVT®, this treatment may lead to an improvement of vowel articulation and coarticulation. Conclusions: Vowel production is modulated by the different therapeutic interventions offered to people with PD. Speech production and, more specifically, vowel articulation and coarticulation should be an integral part of patient evaluation profiles when choosing and optimizing therapeutic management interventions for these patients

More than words: Recognizing speech of people with Parkinson's disease

Parkinson’s disease (PD) is the fastest-growing neurological disorder in the world, with approximately 10 million people currently living with the diagnosis. Hypokinetic dysarthria (HD) is one of the symptoms that appear in early stages of the disease progression. The main aim of this dissertation is to gain insights into listeners’ impressions of dysarthric speech and to uncover acoustic correlates of those impressions. We do this by exploring two sides of communication: speech production of people with PD, and listeners’ recognition of speech of people with PD. Therefore, the studies in this dissertation approach the topic of speech changes in PD from both the speakers' side - via acoustic analysis of speech, and the listeners' side - via experiments exploring the influence of expertise and language background on recognition of speech of people with PD. Moreover, to obtain a more comprehensive picture of these perspectives, the studies of this dissertation are multifaceted, explore cross-linguistic aspects of dysarthric speech recognition and include both cross-sectional and longitudinal designs. The results demonstrate that listeners' ability to recognize speech of people with PD as unhealthy is rooted in the acoustic changes in speech, not in its content. Listeners’ experience in the fields of speech and language therapy or speech sciences affect dysarthric speech recognition. The results also suggest that tracking speech parameters is a useful tool for monitoring the progression and/or development of dysarthria and objectively evaluating long-term effects of speech therapy

Models and Analysis of Vocal Emissions for Biomedical Applications

The International Workshop on Models and Analysis of Vocal Emissions for Biomedical Applications (MAVEBA) came into being in 1999 from the particularly felt need of sharing know-how, objectives and results between areas that until then seemed quite distinct such as bioengineering, medicine and singing. MAVEBA deals with all aspects concerning the study of the human voice with applications ranging from the neonate to the adult and elderly. Over the years the initial issues have grown and spread also in other aspects of research such as occupational voice disorders, neurology, rehabilitation, image and video analysis. MAVEBA takes place every two years always in Firenze, Italy. This edition celebrates twenty years of uninterrupted and succesfully research in the field of voice analysis

Models and Analysis of Vocal Emissions for Biomedical Applications

The MAVEBA Workshop proceedings, held on a biannual basis, collect the scientific papers presented both as oral and poster contributions, during the conference. The main subjects are: development of theoretical and mechanical models as an aid to the study of main phonatory dysfunctions, as well as the biomedical engineering methods for the analysis of voice signals and images, as a support to clinical diagnosis and classification of vocal pathologies

Investigating the motor-sensory learning of foreign speech

This thesis presents an investigation of bilingualism as a motor learning skill, with success ultimately measured in terms of strength of a foreign accent, in contrast to the many studies of bilingualism in terms of linguistic competence. My research used functional magnetic resonance (fMRI) imaging to investigate feedforward (motor) and feedback (auditory and somatosensory) systems involved in the production of foreign speech and how these systems are modulated by proficiency levels. I investigated the function of the frontal operculum and the temporo-parietal junction (TPJ) – planum temporale (posterior auditory association cortex) and parietal operculum (somatosensory association cortex) – during speech. The frontal operculum, strongly lateralised to the left, has been associated with speech since Broca performed his classic post mortem lesion-deficit analysis. Interest in the TPJ has arisen because of recent publications proposing the posterior half of the left planum temporale (± adjacent parietal operculum) as a ‘sensorimotor interface’ for speech production. My research compared activity within the frontal operculum and the TPJ during overt and covert speech. A second fMRI study examined retrospective proficiency based on existing language skills in people with English as a foreign language who were scanned during speech production in their native language and in English. A third fMRI study manipulated proficiency by training monolingual native English participants in the production of foreign speech sounds, with scanning pre- and post-training. This allowed measures of changes in activity (indicating rapid plasticity) following a short period of behavioural training in articulating novel foreign speech sounds. Training effects were observed predominantly in the striatum, and further analyses indicated that striatal activity in vocal learning is modulated by proficiency

Akustische Analyse stimulationsinduzierter Dysarthrie bei Patienten mit essentiellem Tremor und Tiefer Hirnstimulation

Die vorliegende Arbeit beschäftigt sich mit der Frage, inwieweit die Tiefe Hirnstimulation bei Patienten mit Essentiellem Tremor (ET) zu einer Verschlechterung der Sprechmotorik führt. Dabei werden vor allem zwei Konditionen berücksichtigt: (1) Zum einen werden Patienten sowohl prä- als auch postoperativ in die Analyse einbezogen. (2) Zum anderen wird der Einfluss der Stimulation an unterschiedlichen Stimulationsorten untersucht, d.h. die benachbarten Areale Nucleus Ventralis Intermedius (VIM) und Posteriore Subthalamische Area (PSA) werden in die Analyse mit einbezogen. Bei der tieferliegenden PSA verlaufen die Faserbahnen (des dento-thalamischen Traktes) stärker gebündelt als im VIM. Deshalb benötigt die PSA weniger Strom als der VIM, um den Tremor zu unterdrücken, was positiv zu werten ist. Es wurden 13 Patienten in dieser Arbeit eingeschlossen, ebenso eine Gruppe von gesunden, alters- und geschlechts-gematchten Kontrollsprechern. Die Arbeit nutzt einen interdisziplinären Ansatz und kombiniert die Methoden aus Neurologie, funktioneller Neurochirurgie und Phonetik. Die akustischen Aufnahmen werden über phonetische Parameter analysiert, ebenso wurden subjektive Einschätzungen der Sprache durch die Patienten sowie Verständlichkeitsanalysen durch verblindete Hörer durchgeführt. Es werden die Patienten (präoperativ) gegen die Kontrollgruppe, die Patienten prä- und post-operativ (separat für VIM und PSA) und die Sprechmotorik im Direktvergleich zwischen PSA und VIM verglichen. Die Ergebnisse zeigen eine Verschlechterung der Sprechmotorik vor und nach stattgehabter THS, Unterschiede zwischen VIM und PSA sowie präoperativen ET Patienten und Kontrollsprechern finden sich nicht