A cross-linguistic perspective to classification of healthiness of speech in Parkinson's disease

People with Parkinson's disease often experience communication problems. The current cross-linguistic study investigates how listeners' perceptual judgements of speech healthiness are related to the acoustic changes appearing in the speech of people with Parkinson's disease. Accordingly, we report on an online experiment targeting perceived healthiness of speech. We studied the relations between healthiness perceptual judgements and a set of acoustic characteristics of speech in a cross-sectional design. We recruited 169 participants, who performed a classification task judging speech recordings of Dutch speakers with Parkinson's disease and of Dutch control speakers as ‘healthy’ or ‘unhealthy’. The groups of listeners differed in their training and expertise in speech language therapy as well as in their native languages. Such group separation allowed us to investigate the acoustic correlates of speech healthiness without influence of the content of the recordings. We used a Random Forest method to predict listeners' responses. Our findings demonstrate that, independently of expertise and language background, when classifying speech as healthy or unhealthy listeners are more sensitive to speech rate, presence of phonation deficiency reflected by maximum phonation time measurement, and centralization of the vowels. The results indicate that both specifics of the expertise and language background may lead to listeners relying more on the features from either prosody or phonation domains. Our findings demonstrate that more global perceptual judgements of different listeners classifying speech of people with Parkinson's disease may be predicted with sufficient reliability from conventional acoustic features. This suggests universality of acoustic change in speech of people with Parkinson's disease. Therefore, we concluded that certain aspects of phonation and prosody serve as prominent markers of speech healthiness for listeners independent of their first language or expertise. Our findings have outcomes for the clinical practice and real-life implications for subjective perception of speech of people with Parkinson's disease, while information about particular acoustic changes that trigger listeners to classify speech as ‘unhealthy’ can provide specific therapeutic targets in addition to the existing dysarthria treatment in people with Parkinson's disease

Functional data analysis of prosodic prominence in Parkinson's disease: a pilot study

publishedVersionPeer reviewe

Acoustic differences in emotional speech of people with dysarthria

Communicating emotion is essential in building and maintaining relationships. We communicate our emotional state not just with the words we use, but also how we say them. Changes in the rate of speech, short-term energy and intonation all help to convey emotional states like 'angry', 'sad' and 'happy'. People with dysarthria, the most common speech disorder, have reduced articulatory and phonatory control. This can affect the intelligibility of their speech, especially when communicating with unfamiliar conversation partners. However, we know little about how people with dysarthria convey their emotional state, and whether they are having to make changes to their speech to achieve this. In this study, we investigated the ability of people with dysarthria, caused by cerebral palsy and Parkinson's disease, to communicate emotions in their speech, and we compared their speech to that of speakers with typical speech. A parallel database of emotional speech was collected. One female speaker with dysarthria due to cerebral palsy, 3 speakers with dysarthria due to Parkinson's disease (2 female and 1 male), and 21 typical speakers (9 female and 12 male) produced sentences with 'angry', 'happy', 'sad', and 'neutral' emotions. A number of acoustic features were analysed using linear multi-level modeling. The results show that people with dysarthria were able to control some aspects of the suprasegmental and prosodic features when attempting to communicate emotions. For most speakers the changes they made are consistent with the changes made by speakers with typical speech. Even when the changes might be different to that of typical speakers, acoustic analysis shows these were consistent for different emotions. The analysis shows that variation in energy and jitter (local absolute) are major indicators of emotion in the study

The speech intelligibility of English learners of Spanish at Key Stage 4.

PhDThis study offers an assessment of the non-native speech intelligibility of a group of English learners of Spanish at word level and in connected speech. Specifically, we aimed at analysing the impact of certain categories of phonemic errors, as well as three temporal variables of L2 speech (speech rate, pause frequency and pause duration) on intelligibility scores. In addition, the possible correlation between degree of intelligibility and certain individual factors (gender, level of proficiency, motivation, aptitude and L1) was also studied. Sixty evaluators, native speakers of Peninsular Spanish, transcribed different speech samples belonging to a group of 20 Key Stage 4 English learners of Spanish. The transcription of the different speech samples served to assess intelligibility at word level and in connected speech (sentence, passage and semi-spontaneous production). Results revealed an intelligibility loss at all levels of analysis, as well as a high correlation between intelligibility scores in the single word test and those obtained in connected speech. At a segmental level, deviations affecting vowels, especially unstressed vowels, seemed to play a more important role than inaccuracies affecting consonants. Moreover, correlation analyses underscored the importance of speech rate, pause frequency and pause duration for intelligibility loss. The predictability of our multiple-regression models was high for speech samples obtained at sentence and passage levels. However, multiple-regression models for speech samples obtained through the semi-spontaneous production task exhibited a more limited capability in predicting variation in students’ intelligibility scores. Results suggest the existence of additional variables affecting intelligibility at this level of analysis. All individual differences under study, with the exception of gender, were highly correlated with speech intelligibility. From a pedagogical perspective, it is argued here that any successful instructional treatment of speech intelligibility will depend on an appropriate integration of temporal aspects of speech within the time devoted to pronunciation instruction in the foreign language classroom

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

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

Social Aspects of Communication in Parkinson's Disease

Parkinson’s disease is a degenerative neurological condition which affects motor control, in almost all cases involving speech, and is frequently of many years duration. Much is known about speech production but less of the psychosocial consequences of the speech impairment (dysarthria). Accounts of people with dysarthria have shown that its impact on quality of social participation can be varied and profound. However, level of participation has not been investigated. Reduction in social activity and social networks has been found following onset of other neurogenic communication disorders. In Parkinson’s disease there is some evidence of social activity reduction but this has not been studied in relation to severity of dysarthria. Social anxiety has been found to be raised in speakers with other speech production impairments and this may be a contributor to reduction in social engagement. Investigation of social variables is of importance in understanding relationships within a biopsychosocial model of health which underpins intervention for therapies for communication disorders. Aims The study aimed to investigate the impact of dysarthria on social participation and whether presence of dysarthria in Parkinson’s disease (PD) resulted in changes to social anxiety, social networks and social activity. It further sought to investigate whether severity of dysarthria resulted in changes to the same variables. Method A group of 43 mild-moderately dysarthric speakers with PD were recruited. Exclusion criteria were applied to control for cognitive impairment, depression, apathy, movement disability and co-occurring neurological and communication impairment. A group of 30 non-neurologically impaired participants were recruited matched for age, sex, socioeconomic status and educational attainment. Participants with PD were further grouped using measures of sentence intelligibility and motor speech impairment into higher and lower functioning groups. All participants completed a social anxiety questionnaire, a social activity checklist and detailed their social network. Group data were compared to address the research questions. Semi-structured interviews were carried out with all participants to explore change to social life and perceptions of causes of change. Results Participants reported a range of changes to interaction and social engagement arising from speech and other impairments and also from intra and interpersonal contextual factors. Quantitative data showed that presence of dysarthria was associated with social anxiety and avoidance but not changes to social activity level or social network size. Greater severity of dysarthria was associated with deterioration in social activities and social network. There was wide individual variation on these variables. Outcomes Impact of dysarthria may be significant and unrelated to severity of impairment and satisfaction with level of activity is low in dysarthric speakers. Mild - moderately dysarthric speakers with PD may experience social anxiety in particular types of social situation. Moderately dysarthric speakers may experience loss of social capital in terms of quantitative changes in social networks and social activities. Motor speech impairment was a better predictor of social functioning than intelligibility in this sample. It is possible that a threshold for change lies at a more severe level of speech involvement. How speakers with PD perceive and experience their social interactions is discussed and limitations to the research are considered. The implications of the findings are discussed in relation to the ICF framework and the concept of social capita