scholarly journals Neuromechanical Modelling of Articulatory Movements from Surface Electromyography and Speech Formants

2019 ◽  
Vol 29 (02) ◽  
pp. 1850039 ◽  
Author(s):  
Pedro Gómez-Vilda ◽  
Andrés Gómez-Rodellar ◽  
José M. Ferrández Vicente ◽  
Jiri Mekyska ◽  
Daniel Palacios-Alonso ◽  
...  
Keyword(s):  
Probability Density Function ◽  
Vertical Velocity ◽  
Surface Electromyography ◽  
Muscular Activity ◽  
Electromyographic Activity ◽  
Acoustic Features ◽  
Articulatory Movements ◽  
Vowel Space ◽  
Preliminary Study ◽  
Derivatives Of

Speech articulation is produced by the movements of muscles in the larynx, pharynx, mouth and face. Therefore speech shows acoustic features as formants which are directly related with neuromotor actions of these muscles. The first two formants are strongly related with jaw and tongue muscular activity. Speech can be used as a simple and ubiquitous signal, easy to record and process, either locally or on e-Health platforms. This fact may open a wide set of applications in the study of functional grading and monitoring neurodegenerative diseases. A relevant question, in this sense, is how far speech correlates and neuromotor actions are related. This preliminary study is intended to find answers to this question by using surface electromyographic recordings on the masseter and the acoustic kinematics related with the first formant. It is shown in the study that relevant correlations can be found among the surface electromyographic activity (dynamic muscle behavior) and the positions and first derivatives of the first formant (kinematic variables related to vertical velocity and acceleration of the joint jaw and tongue biomechanical system). As an application example, it is shown that the probability density function associated to these kinematic variables is more sensitive than classical features as Vowel Space Area (VSA) or Formant Centralization Ratio (FCR) in characterizing neuromotor degeneration in Parkinson’s Disease.

scholarly journals Synchronization of surface electromyography and 3D electromagnetic articulography applied to study the biomechanics of the mandible: proof of concept.

2019 ◽  
Author(s):  
Florencia Lezcano ◽  
Fernando Jose Dias ◽  
Constanza Farfán ◽  
María Cristina Manzanares Céspedes ◽  
Ramon Fuentes
Keyword(s):  
Healthy Volunteer ◽  
Surface Electromyography ◽  
Electromyographic Activity ◽  
Proof Of Concept ◽  
Electromagnetic Articulography ◽  
Articulatory Movements ◽  
Mandibular Movements ◽  
Switch Module ◽  
Standard Components ◽  
Semg Signals

Abstract Background. The aim of this study was to propose and establish the proof of concept of an approach to synchronize 3D Electromagnetic Articulography (3D-EMA) with Surface Electromyography (SEMG) systems based on the standard components of these equipment. Methods. Initially it was planned and obtained the required equipment with the appropriate characteristics required, and them it was created the proper conditions to register the synchronized signals provided by both systems. Thus, we selected a SEMG with a switch module incorporated to be able to achieve synchronization of signals. After the system setup was stablished, chewing tasks were recorded on a healthy volunteer, collecting a proof-of-concept database. The variability among recordings of the database were analyzed in order to detect possible interferences. Results. The analysis of the chewing task recordings obtained with the synchronized 3D EMA and SEMG signals in the present study did not reveal significant distortions, all values were within the informed by the manufacturers of both systems. The method presented the advantage of using only components that are already included with the equipment employed.Conclusion. The method of analysis described in this paper is an effective tool that facilitates the investigation of mandibular movements synchronized in two domains: articulatory movements and electromyographic activity. Thus, it is promising to be applied in different clinical situations to improve the analysis of the complexity of masticatory activity, in addition being able to generate new insights on this topic.

scholarly journals PRELIMINARY STUDY OF HORIZONTAL AND VERTICAL WIND PROFILE OF QUASI-LINEAR CONVECTIVE UTILIZING WEATHER RADAR OVER WESTERN JAVA REGION, INDONESIA

2019 ◽  
Vol 15 (2) ◽  
pp. 177
Author(s):  
Abdullah Ali ◽  
Riris Adrianto ◽  
Miming Saepudin
Keyword(s):  
Velocity Profile ◽  
Vertical Velocity ◽  
Wind Shear ◽  
Vertical Wind Shear ◽  
Convective Cloud ◽  
Vertical Wind ◽  
Squall Line ◽  
Vertical Velocity Profile ◽  
Preliminary Study ◽  
Wind Profiles

One of the weather phenomena that potentially cause extreme weather conditions is the linear-shaped mesoscale convective systems, including squall lines. The phenomenon that can be categorized as a squall line is a convective cloud pair with the linear pattern of more than 100 km length and 6 hours lifetime. The new theory explained that the cloud system with the same morphology as squall line without longevity threshold. Such a cloud system is so-called Quasi-Linear Convective System (QLCS), which strongly influenced by the ambient dynamic processes, include horizontal and vertical wind profiles. This research is intended as a preliminary study for horizontal and vertical wind profiles of QLCS developed over the Western Java region utilizing Doppler weather radar. The following parameters were analyzed in this research, include direction pattern and spatial-temporal significance of wind speed, divergence profile, vertical wind shear (VWS) direction, and intensity profiles, and vertical velocity profile. The subjective and objective analysis was applied to explain the characteristics and effects of those parameters to the orientation of propagation, relative direction, and speed of the cloud system’s movement, and the lifetime of the system. Analysis results showed that the movement of the system was affected by wind direction and velocity patterns. The divergence profile combined with the vertical velocity profile represents the inflow which can supply water vapor for QLCS convective cloud cluster. Vertical wind shear that effect QLCS system is only its direction relative to the QLCS propagation, while the intensity didn’t have a significant effect.

scholarly journals A new subgrid-scale representation of hydrometeor fields using a multivariate PDF

2016 ◽  
Author(s):  
Brian M. Griffin ◽  
Vincent E. Larson
Keyword(s):  
Probability Density Function ◽  
Probability Density ◽  
Density Function ◽  
Vertical Velocity ◽  
Lognormal Distribution ◽  
Large Eddy Simulations ◽  
Subgrid Scale ◽  
Microphysical Process ◽  
Large Eddy ◽  
Probability Density Function Pdf

Abstract. The subgrid-scale representation of hydrometeor fields is important for calculating microphysical process rates. In order to represent subgrid-scale variability, the Cloud Layers Unified By Binormals (CLUBB) parameterization uses a multivariate Probability Density Function (PDF). In addition to vertical velocity, temperature, and moisture fields, the PDF includes hydrometeor fields. Previously, each hydrometeor field was assumed to follow a multivariate single lognormal distribution. Now, in order to better represent the distribution of hydrometeors, two new multivariate PDFs are formulated and introduced. The new PDFs represent hydrometeors using either a delta-lognormal or a delta-double-lognormal shape. The two new PDF distributions, plus the previous single lognormal shape, are compared to histograms of data taken from Large-Eddy Simulations (LES) of a precipitating cumulus case, a drizzling stratocumulus case, and a deep convective case. Finally, the warm microphysical process rates produced by the different hydrometeor PDFs are compared to the same process rates produced by the LES.

Overestimation of Bispectral Index in Sedated Intensive Care Unit Patients Revealed by Administration of Muscle Relaxant

2003 ◽  
Vol 99 (1) ◽  
pp. 9-17 ◽  
Author(s):  
Benoît Vivien ◽  
Sophie Di Maria ◽  
Alexandre Ouattara ◽  
Olivier Langeron ◽  
Pierre Coriat ◽  
...  
Keyword(s):  
Intensive Care Unit ◽  
Intensive Care ◽  
Neuromuscular Blockade ◽  
Bispectral Index ◽  
Muscle Relaxant ◽  
Muscular Activity ◽  
Electromyographic Activity ◽  
Adductor Pollicis Muscle ◽  
Number Of Patients ◽  
Before And After

Background Electromyographic activity has previously been reported to elevate the Bispectral Index (BIS) in patients not receiving neuromuscular blockade while under sedation in the intensive care unit. This study aimed to investigate the magnitude of the decrease of BIS following administration of muscle relaxant in sedated intensive care unit patients. Methods The authors prospectively investigated 45 patients who were continuously sedated with midazolam and sufentanil to achieve a Sedation-Agitation Scale value equal to 1 and who required administration of muscle relaxant. BIS (BIS version 2.10), electromyography, and acceleromyography at the adductor pollicis muscle were recorded simultaneously before and after neuromuscular blockade. Sixteen of these 45 patients were also studied simultaneously with the new BIS XP. Results After administration of a muscle relaxant, BIS (67 +/- 19 vs. 43 +/- 10, P < 0.001) and electromyographic activity (37 +/- 9 vs. 27 +/- 3 dB, P < 0.001) significantly decreased. Multiple regression analysis showed that the decrease of BIS following administration of myorelaxant was significantly correlated to BIS and electromyographic baseline values. Using standard BIS range guidelines, the number of patients under light or deep sedation versus general anesthesia or deep hypnotic state was markedly overestimated before administration of myorelaxant (53 vs. 2%, P < 0.001). Conclusions The BIS in sedated intensive care unit patients may be lower with paralysis for an equivalent degree of sedation because of high muscular activity. The magnitude of BIS overestimation is significantly correlated to both BIS and electromyographic activity before neuromuscular blockade. The authors conclude that clinicians who determine the amount of sedation in intensive care unit patients only from BIS monitoring may expose them to unnecessary oversedation.

scholarly journals Electromyographic activity of the vastus medialis and gastrocnemius implicates a slow stretch-shortening cycle during rowing in the field

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Steffen Held ◽  
Tobias Siebert ◽  
Lars Donath
Keyword(s):  
Performance Enhancement ◽  
Muscular Activity ◽  
Emg Activity ◽  
Electromyographic Activity ◽  
Vastus Medialis ◽  
Leg Muscles ◽  
Rowing Performance ◽  
Specific Muscle ◽  
Two Phases ◽  
Activation Phase

Abstract The consideration of the temporal and electromyographic (EMG) characteristics of stretch-shortening cycles (SSC) are crucial for the conceptualization of discipline-specific testing and training. Since leg muscles are first stretched (eccentric) and then contracted (concentric) during rowing, it can be assumed that the entire muscle tendon complex performs a SSC. Thus, it should be elucidated whether the rowing cycle can be attributed to either a slow or fast SSC. Therefore, EMG of the vastus medialis and gastrocnemius were captured (n = 10, 22.8 ± 3.1 years, 190 ± 6 cm, 82.1 ± 9.8 kg) during (single scull) rowing and subsequently compared to typical slow (countermovement jump, CMJ) and fast (drop jump, DJ) SSCs. The elapsed time between the EMG onset and the start of the eccentric phase was monitored. The pre-activation phase (PRE, before the start of the eccentric phase) and the reflex-induced activation phase (RIA 30–120 ms after the start of the eccentric phase) have been classified. Notable muscular activity was observed during DJ before the start of the eccentric phase (PRE) as well as during RIA. In contrast, neither CMJ nor rowing revealed any EMG-activity in these two phases. Interestingly, CMJ and race-specific rowing showed an EMG-onset during the eccentric phase. We conclude that rowing is more attributable to a slow SSC and implies that fast SSC does not reflect discipline specific muscle action and could hamper rowing-performance-enhancement.

scholarly journals Detection of swallowing disorders using a multiple channel surface electromyography sheet: A preliminary study

2021 ◽  
Vol 16 (1) ◽  
pp. 160-167
Author(s):  
Yoshito Koyama ◽  
Nobuyuki Ohmori ◽  
Hideya Momose ◽  
Eiji Kondo ◽  
Shin-ichi Yamada ◽  
...  
Keyword(s):  
Surface Electromyography ◽  
Swallowing Disorders ◽  
Multiple Channel ◽  
Channel Surface ◽  
Preliminary Study
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