Methodologies of speech analysis for neurodegenerative diseases evaluation

Chronic respiratory failure negatively affects speech function in patients with bulbar and spinal onset amyotrophic lateral sclerosis: retrospective data from a tertiary referral center

Background: Although dysarthria and respiratory failure are widely described in literature as part of the natural history of Amyotrophic lateral sclerosis (ALS), the specific interaction between them has been little explored.Aim: To investigate the relationship between chronic respiratory failure and the speech of ALS patients.Materials and methods: In this cross-sectional retrospective study we reviewed the medical records of all patients diagnosed with ALS that were accompanied by a tertiary referral center. In order to determine the presence and degree of speech impairment, the Amyotrophic Lateral Sclerosis Functional Rating Scale-revised (ALSFRS-R) speech sub-scale was used. Respiratory function was assessed through spirometry and through venous blood gasometry obtained from a morning peripheral venous sample. To determine whether differences among groups classified by speech function were significant, maximum and mean spirometry values of participants were compared using multivariate analysis of variance (MANOVA) with Tukey's post hoc test.Results: Seventy-five cases were selected, of which 73.3% presented speech impairment and 70.7% respiratory impairment. Respiratory and speech functions were moderately correlated (seated FVC r = 0.64; supine FVC r = 0.60; seated FEV1 r = 0.59 and supine FEV1 r = 0.54, p < .001). Multivariable logistic regression revealed that the following variables were significantly associated with the presence of speech impairment after adjusting for other risk factors: seated FVC (odds ratio [OR] = 0.862) and seated FEV1 (OR = 1.106). The final model was 81.1% predictive of speech impairment. The presence of daytime hypercapnia was not correlated to increasing speech impairment.Conclusion: The restrictive pattern developed by ALS patients negatively influences speech function. Speech is a complex and multifactorial process, and lung volume presents a pivotal role in its function. Thus, we were able to find that lung volumes presented a significant correlation to speech function, especially in those with bulbar onset and respiratory impairment. Neurobiological and physiological aspects of this relationship should be explored in further studies with the ALS population.

Patient-specific game-based transfer method for Parkinson's disease severity prediction

Dysphonia is one of the early symptoms of Parkinson's disease (PD). Most existing methods use feature selection methods to find the optimal subset of voice features for all PD patients. Few have considered the heterogeneity between patients, which implies the need to provide specific prediction models for different patients. However, building the specific model faces the challenge of small sample size, which makes it lack generalization ability. Instance transfer is an effective way to solve this problem. Therefore, this paper proposes a patient-specific game-based transfer (PSGT) method for PD severity prediction. First, a selection mechanism is used to select PD patients with similar disease trends to the target patient from the source domain, which reduces the risk of negative transfer. Then, the contribution of the transferred subjects and their instances to the disease estimation of the target subject is fairly evaluated by the Shapley value, which improves the interpretability of the method. Next, the proportion of valid instances in the transferred subjects is determined, and the instances with higher contribution are transferred to further reduce the difference between the transferred instance subset and the target subject. Finally, the selected subset of instances is added to the training set of the target subject, and the extended data is fed into the random forest to improve the performance of the method. Parkinson's telemonitoring dataset is used to evaluate the feasibility and effectiveness. The mean values of mean absolute error, root mean square error, and volatility obtained by predicting motor-UPDRS and total-UPDRS for target patients are 1.59, 1.95, 1.56 and 1.98, 2.54, 1.94, respectively. Experiment results show that the PSGT has better performance in both prediction error and stability over compared methods.

Subclinical articulatory changes of vowel parameters in Korean amyotrophic lateral sclerosis patients with perceptually normal voices

The available quantitative methods for evaluating bulbar dysfunction in patients with amyotrophic lateral sclerosis (ALS) are limited. We aimed to characterize vowel properties in Korean ALS patients, investigate associations between vowel parameters and clinical features of ALS, and analyze subclinical articulatory changes of vowel parameters in those with perceptually normal voices. Forty-three patients with ALS (27 with dysarthria and 16 without dysarthria) and 20 healthy controls were prospectively collected in the study. Dysarthria was assessed using the ALS Functional Rating Scale-Revised (ALSFRS-R) speech subscores, with any loss of 4 points indicating the presence of dysarthria. The structured speech samples were recorded and analyzed using Praat software. For three corner vowels (/a/, /i/, and /u/), data on the vowel duration, fundamental frequency, frequencies of the first two formants (F1 and F2), harmonics-to-noise ratio, vowel space area (VSA), and vowel articulation index (VAI) were extracted from the speech samples. Corner vowel durations were significantly longer in ALS patients with dysarthria than in healthy controls. The F1 frequency of /a/, F2 frequencies of /i/ and /u/, the VSA, and the VAI showed significant differences between ALS patients with dysarthria and healthy controls. The area under the curve (AUC) was 0.912. The F1 frequency of /a/ and the VSA were the major determinants for differentiating ALS patients who had not yet developed apparent dysarthria from healthy controls (AUC 0.887). In linear regression analyses, as the ALSFRS-R speech subscore decreased, both the VSA and VAI were reduced. In contrast, vowel durations were found to be rather prolonged. The analyses of vowel parameters provided a useful metric correlated with disease severity for detecting subclinical bulbar dysfunction in ALS patients.

Acoustic Voice Analysis as a Useful Tool to Discriminate Different ALS Phenotypes

Approximately 80-96% of people with amyotrophic lateral sclerosis (ALS) become unable to speak during the disease progression. Assessing upper and lower motor neuron impairment in bulbar regions of ALS patients remains challenging, particularly in distinguishing spastic and flaccid dysarthria. This study aimed to evaluate acoustic voice parameters as useful biomarkers to discriminate ALS clinical phenotypes. Triangular vowel space area (tVSA), alternating motion rates (AMRs), and sequential motion rates (SMRs) were analyzed in 36 ALS patients and 20 sex/age-matched healthy controls (HCs). tVSA, AMR, and SMR values significantly differed between ALS and HCs, and between ALS with prevalent upper (pUMN) and lower motor neuron (pLMN) impairment. tVSA showed higher accuracy in discriminating pUMN from pLMN patients. AMR and SMR were significantly lower in patients with bulbar onset than those with spinal onset, both with and without bulbar symptoms. Furthermore, these values were also lower in patients with spinal onset associated with bulbar symptoms than in those with spinal onset alone. Additionally, AMR and SMR values correlated with the degree of dysphagia. Acoustic voice analysis may be considered a useful prognostic tool to differentiate spastic and flaccid dysarthria and to assess the degree of bulbar involvement in ALS.

Extracting Phonetic Posterior-Based Features for Detecting Multiple Sclerosis From Speech

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system which, in addition to affecting motor and cognitive functions, may also lead to specific changes in the speech of patients. Speech production, comprehension, repetition and naming tasks, as well as structural and content changes in narratives, might indicate a limitation of executive functions. In this study we present a speech-based machine learning technique to distinguish speakers with relapsing-remitting subtype MS and healthy controls (HC). We exploit the fact that MS might cause a motor speech disorder similar to dysarthria, which, with our hypothesis, might affect the phonetic posterior estimates supplied by a Deep Neural Network acoustic model. From our experimental results, the proposed posterior posteriorgram-based feature extraction approach is useful for detecting MS: depending on the actual speech task, we obtained Equal Error Rate values as low as 13.3%, and AUC scores up to 0.891, indicating a competitive and more consistent classification performance compared to both the x-vector and the openSMILE 'ComParE functionals' attributes. Besides this discrimination performance, the interpretable nature of the phonetic posterior features might also make our method suitable for automatic MS screening or monitoring the progression of the disease. Furthermore, by examining which specific phonetic groups are the most useful for this feature extraction process, the potential utility of the proposed phonetic features could also be utilized in the speech therapy of MS patients.

Biomechanical Parameters of Voice in Parkinson's Disease Patients

INTRODUCTION

Previous research on voice in Parkinson's disease (PD) has consistently demonstrated alterations in acoustic parameters, including fundamental frequency (F0), maximum phonation time, Shimmer, and Jitter. However, investigations into acoustic parameter alterations in individuals with PD are limited.

METHODS

We conducted an experimental study involving 20 PD patients (six women and fourteen men). Subjective measures of voice (VHI-30 scale and GRBAS) and objective measures using the OnlineLAB App tool for analyzing biomechanical correlates of voice were recorded. The app analyzed a total of 22 biomechanical parameters of voice.

RESULTS

The results of subjective measures were consistent with findings from previous studies. However, the results of objective measures did not align with studies that employed acoustic measures.

CONCLUSIONS

The biomechanical analysis revealed alterations in various parameters according to gender. These findings open up a new avenue of research in voice analysis for patients with PD, whether through acoustic or biomechanical analysis, aiming to determine whether the observed changes in these patients' voices are attributable to age or disease progression. This line of investigation will help elucidate the relative contribution of these factors to vocal alterations in PD patients and provide a more comprehensive understanding of the underlying mechanisms.

Articulatory speech measures can be related to the severity of multiple sclerosis

Background

Dysarthria is one of the most frequent communication disorders in patients with Multiple Sclerosis (MS), with an estimated prevalence of around 50%. However, it is unclear if there is a relationship between dysarthria and the severity or duration of the disease.

Objective

Describe the speech pattern in MS, correlate with clinical data, and compare with controls.

Methods

A group of MS patients (n = 73) matched to healthy controls (n = 37) by sex and age. Individuals with neurological and/or systemic conditions that could interfere with speech were excluded. MS group clinical data were obtained through the analysis of medical records. The speech assessment consisted of auditory-perceptual and speech acoustic analysis, from recording the following speech tasks: phonation and breathing (sustained vowel/a/); prosody (sentences with different intonation patterns) and articulation (diadochokinesis; spontaneous speech; diphthong/iu/repeatedly).

Results

In MS, 72.6% of the individuals presented mild dysarthria, with alterations in speech subsystems: phonation, breathing, resonance, and articulation. In the acoustic analysis, individuals with MS were significantly worse than the control group (CG) in the variables: standard deviation of the fundamental frequency (p = 0.001) and maximum phonation time (p = 0.041). In diadochokinesis, individuals with MS had a lower number of syllables, duration, and phonation time, but larger pauses per seconds, and in spontaneous speech, a high number of pauses were evidenced as compared to CG. Correlations were found between phonation time in spontaneous speech and the Expanded Disability Status Scale (EDSS) (r = - 0.238, p = 0.043) and phonation ratio in spontaneous speech and EDSS (r = -0.265, p = 0.023), which indicates a correlation between the number of pauses during spontaneous speech and the severity of the disease.

Conclusion

The speech profile in MS patients was mild dysarthria, with a decline in the phonatory, respiratory, resonant, and articulatory subsystems of speech, respectively, in order of prevalence. The increased number of pauses during speech and lower rates of phonation ratio can reflect the severity of MS.

Speech disorders in patients with Tongue squamous cell carcinoma: A longitudinal observational study based on a questionnaire and acoustic analysis

BACKGROUND

Speech disorders are common dysfunctions in patients with tongue squamous cell carcinoma (TSCC) that can diminish their quality of life. There are few studies with multidimensional and longitudinal assessments of speech function in TSCC patients.

METHODS

This longitudinal observational study was conducted at the Hospital of Stomatology, Sun Yat-sen University, China, from January 2018 to March 2021. A cohort of 92 patients (53 males, age range: 24-77 years) diagnosed with TSCC participated in this study. Speech function was assessed from preoperatively to one year postoperatively using the Speech Handicap Index questionnaire and acoustic parameters. The risk factors for postoperative speech disorder were analyzed by a linear mixed-effects model. A t test or Mann‒Whitney U test was applied to analyze the differences in acoustic parameters under the influence of risk factors to determine the pathophysiological mechanisms of speech disorders in patients with TSCC.

RESULTS

The incidence of preoperative speech disorders was 58.7%, which increased up to 91.4% after surgery. Higher T stage (P＜0.001) and larger range of tongue resection (P = 0.002) were risk factors for postoperative speech disorders. Among the acoustic parameters, F2/i/decreased remarkably with higher T stage (P = 0.021) and larger range of tongue resection (P = 0.009), indicating restricted tongue movement in the anterior-posterior direction. The acoustic parameters analysis during the follow-up period showed that F1 and F2 were not significantly different of the patients with subtotal or total glossectomy over time.

CONCLUSIONS

Speech disorders in TSCC patients is common and persistent. Less residual tongue volume led to worse speech-related QoL, indicating that surgically restoring the length of the tongue and strengthening tongue extension postoperatively may be important.

Perceptual and qualitative voice alterations detected by GIRBAS in patients with Parkinson's disease: is there a relation with lung function and oxygenation?

BACKGROUND

Impairments in respiration, voice and speech are common in people with Parkinson's disease (PD).

AIMS

To evaluate the prevalence of dysphonia, assessed by a specific acoustic evaluation and description of the voice by the speech therapist (GIRBAS), and its relation with lung function and oxygenation, in particular cough ability and during the night or exercise desaturation.

METHODS

This is a posthoc analysis of a prospective cross-sectional observational study on PD patients collecting anthropometric and clinical data, comorbidities, PD severity, motor function and balance, respiratory function at rest, during exercise and at night, voice function with acoustic analysis and presence of speech disorders, in addition to the GIRBAS scale. Based on GIRBAS Global dysphonia ('G') score, we divided patients into dysphonic (moderate-to-severe deviance from the euphonic condition) vs. no/mild dysphonic and analyzed the relations with respiratory impairments.

RESULTS

We analyzed 55 patients and found significant impairments in both respiratory and voice/speech functions. Most patients (85.5%) presented mild-to-severe deviance from the euphonic condition in at least one GIRBAS perceptual element (80% of cases for Global dysphonia) and only 14.5% did not show deviance in all elements simultaneously. At Odds Ratio analysis, the risk of presenting nocturnal desaturation and reduced peak cough expiratory flow was approximately 24 and 8 times higher, respectively, in dysphonic patients vs. those with no/mild dysphonia.

CONCLUSION

Perceptual and qualitative evaluation of the voice with GIRBAS showed that mild-to-severe dysphonia was highly prevalent in PD patients, and associated with nocturnal oxygen desaturation and poor cough ability.

Computational analysis of the sequence-structure relation in SARS-CoV-2 spike protein using protein contact networks

The structure of proteins impacts directly on the function they perform. Mutations in the primary sequence can provoke structural changes with consequent modification of functional properties. SARS-CoV-2 proteins have been extensively studied during the pandemic. This wide dataset, related to sequence and structure, has enabled joint sequence-structure analysis. In this work, we focus on the SARS-CoV-2 S (Spike) protein and the relations between sequence mutations and structure variations, in order to shed light on the structural changes stemming from the position of mutated amino acid residues in three different SARS-CoV-2 strains. We propose the use of protein contact network (PCN) formalism to: (i) obtain a global metric space and compare various molecular entities, (ii) give a structural explanation of the observed phenotype, and (iii) provide context dependent descriptors of single mutations. PCNs have been used to compare sequence and structure of the Alpha, Delta, and Omicron SARS-CoV-2 variants, and we found that omicron has a unique mutational pattern leading to different structural consequences from mutations of other strains. The non-random distribution of changes in network centrality along the chain has allowed to shed light on the structural (and functional) consequences of mutations.

Synthesis, characterization, and in silico studies of 1,8-naphthyridine derivatives as potential anti-Parkinson's agents

1,8-Naphthyridine scaffold is a nitrogen-containing heterocyclic compound known for its versatile biological activities. The structure-activity relationship (SAR) has shown that modification at the 3rd position of the nucleus with various secondary amines enhances the binding efficiency and potency towards the Adenosine receptor (A2A type). In this paper, we have reported some newly synthesized derivatives of 1,8- Naphthyridine, and the prepared compounds were assessed for their potential to constrain A2A receptors through molecular docking. Based on the SAR studies, modifications were done at the 3rd position of the nucleus by incorporating secondary amines. The synthesized compounds were characterized by FT-IR, ¹H and ¹³C NMR. All the synthesized compounds 10a-f and 13a-e showed good binding efficiency towards the A2A receptors and might act as an A2A receptor antagonist, as predicted by in-silico studies. 1-Ethyl-7-methyl-3-(pyrrolidine-1-carbonyl)-1,8-naphthyridine-4(1H)-one (10c) in first series showed the highest docking score of -8.407 and binding energy (MMGBSA dG bind) of -56.60 kcal/mol and N-(4-2-diethylaminoethoxyphenyl)-1-ethyl-7-methyl-4-oxo-1, 4, 4a, 8a- tetrahydro-1,8-naphthyridine-3-carboxamide (13b) showed the highest docking score of -8.562 and free binding energy (MMGBSA dG bind) score of -64.13 kcal/mol which was comparable to the bound ligand. MD simulations study also suggested that compounds 10c and 13b would form stable complex human A2A receptor. These findings need to be validated by further in vitro assays.Communicated by Ramaswamy H. Sarma.

Wearable sensors and features for diagnosis of neurodegenerative diseases: A systematic review

Objective

Neurodegenerative diseases affect millions of families around the world, while various wearable sensors and corresponding data analysis can be of great support for clinical diagnosis and health assessment. This systematic review aims to provide a comprehensive overview of the existing research that uses wearable sensors and features for the diagnosis of neurodegenerative diseases.

Methods

A systematic review was conducted of studies published between 2015 and 2022 in major scientific databases such as Web of Science, Google Scholar, PubMed, and Scopes. The obtained studies were analyzed and organized into the process of diagnosis: wearable sensors, feature extraction, and feature selection.

Results

The search led to 171 eligible studies included in this overview. Wearable sensors such as force sensors, inertial sensors, electromyography, electroencephalography, acoustic sensors, optical fiber sensors, and global positioning systems were employed to monitor and diagnose neurodegenerative diseases. Various features including physical features, statistical features, nonlinear features, and features from the network can be extracted from these wearable sensors, and the alteration of features toward neurodegenerative diseases was illustrated. Moreover, different kinds of feature selection methods such as filter, wrapper, and embedded methods help to find the distinctive indicator of the diseases and benefit to a better diagnosis performance.

Conclusions

This systematic review enables a comprehensive understanding of wearable sensors and features for the diagnosis of neurodegenerative diseases.

Desempeño fonético-acústico de vocales en hablantes del español chileno con enfermedad de Parkinson en estadios iniciales

La articulación de los sonidos lingüísticos consonánticos y vocálicos se afecta en la enfermedad de Parkinson (EP). En el caso de las vocales, esta alteración se manifiesta acústicamente en la estructura formántica y en el área de espacio vocálico. Debido a que no se ha explorado esta temática en Chile, la investigación tuvo por objetivo contrastar el desempeño fonético-acústico de vocales entre hablantes del español chileno con EP inicial y sin la enfermedad. Se efectuó un estudio cuantitativo, cuasiexperimental y correlacional. 15 hablantes con EP (M=69.6 años, DE=7.46) y 15 sin EP (M=70.07 años, DE=7.75) leyeron 30 frases que contenían las cinco vocales del español de Chile. Se analizaron los centros de frecuencia (F1 y F2) y los anchos de banda (B1 y B2) de los formantes vocálicos, y cinco índices del área de espacio vocálico. Se evidenciaron diferencias en el B2 de /i/ y /u/ entre personas con y sin EP; en el F1 de /e/ y /u/, el F2 de /u/, el B1 de /e/ y el B2 de /o/ entre hombres con y sin EP; y en el B2 de /i/ entre mujeres con y sin EP (p<.05). De esta forma, se reporta el desempeño acústico de las vocales en hablantes del español chileno con enfermedad de Parkinson.

Effect of Resonance Tube Technique on Oropharyngeal Geometry and Voice in Individuals with Parkinson's Disease

OBJECTIVE

To verify the immediate effect of the flexible resonance tube vocal technique on the oropharyngeal geometry and vocal acoustic parameters of individuals with Parkinson's disease (PD) and to study the correlation between oropharyngeal geometry and the intensity and fundamental frequency (f0) parameters of the voice.

METHODS

Forty individuals participated-20 with PD and 20 healthy individuals, with a mean age of 60.95 (± 5.69) years. There were 10 men and 10 women in each group. All underwent pharyngometric analysis of the vocal tract and voice acoustics parameters before and after use of the vocal technique with a flexible resonance tube.

RESULTS

After the technique, there was a reduction in pharyngeal cavity volume only in females in the healthy group, a reduction in shimmer values in females in both groups and males in PD group and an improvement in noise parameters in females in the PD group. There was a negative correlation between vocal tract volume and intensity, between f0 and vocal tract volume, between f0 and oropharyngeal junction area, between f0 and oral cavity volume as well as a positive correlation between oral cavity length and f0.

CONCLUSION

The vocal technique with the flexible resonance tube applied to individuals with PD improved the subjects' voice quality in the perceptual and acoustic voice parameters. Regarding the oropharyngeal geometry, it was possible to observe its correlation with the parameters of vocal intensity and frequency in the studied population.