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Artemiadis Panagiotis K - - 2010
Human-robot control interfaces have received increased attention during the past decades. With the introduction of robots in everyday life, especially in providing services to people with special needs (i.e., elderly, people with impairments, or people with disabilities), there is a strong necessity for simple and natural control interfaces. In this ...
van der Meer J N - - 2010
OBJECTIVE: Current template-based artifact reduction methods are inadequate to reduce irregular volume- and slice-artifacts induced by limb motion in combined (surface) EMG-fMRI (electromyography-functional magnetic resonance imaging) studies. In addition, artifacts are not removed adequately for EMG frequencies above 50 Hz. We present a new fMRI artifact reduction algorithm for motion ...
Kallio J - - 2010
Both contraction type and ageing may cause changes in H-reflex excitability. H reflex is partly affected by presynaptic inhibition that may also be an important factor in the control of MU activation. The purpose of the study was to examine age related changes in H-reflex excitability and motor unit activation ...
Zuniga Jorge M - - 2010
The purposes of this study were threefold: (1) to compare the power output related patterns of absolute and normalized MMG amplitude and MPF responses for proximal and distal accelerometer placements on the vastus lateralis (VL) muscle during incremental cycle ergometry; (2) to examine the influence of accelerometer placements on mean ...
Ye-Lin Y - - 2010
Myoelectrical recording could provide an alternative technique for assessing intestinal motility, which is a topic of great interest in gastroenterology since many gastrointestinal disorders are associated with intestinal dysmotility. The pacemaker activity (slow wave, SW) of the electroenterogram (EEnG) has been detected in abdominal surface recordings, although the activity related ...
Watanabe Masato M Department of Computational Intelligence and System Science, Tokyo Institute of Technology, Yokohama, Japan. - - 2010
A motion controller which has an acceleration sensor increases reality and intuitiveness in sports games. But we adjust not only visible posture but also invisible force like stiffness and viscosity when we play sports. We propose a game controller using player's movement and force by using acceleration and electromyogram(EMG). In ...
Kobayashi Yutaro Y Graduate School of Information Science and Technology, the University of Tokyo, Japan. - - 2010
Electromyographic (EMG) signals have been used to control active prosthetic arms for amputees. One of the obstacles in making such prosthetic arms is the timed estimation of posture, because EMG signals and muscle movements are not necessarily synchronized. We estimated the finger motions for trumpet players by using both surface ...
Pérez Rodrigo - - 2010
Here an inertial sensor-based monitoring system for measuring and analyzing upper limb movements is presented. The final goal is the integration of this motion-tracking device within a portable rehabilitation system for brain injury patients. A set of four inertial sensors mounted on a special garment worn by the patient provides ...
Li Guanglin G Institute of Biomedical and Health Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Guangdong 518055 China. - - 2010
Most previous studies of electromyography (EMG) pattern recognition control of multifunctional myoelectric prostheses adopted a conventional sampling rate that is commonly used in EMG research fields. However, it is unknown whether using a lower sampling rate in EMG acquisition still preserves sufficient neural control information for accurate classification of user ...
Vinken Maartje P G C - - 2010
Objective. Evaluating changes in the power spectral density (PSD) peak frequency of the electrohysterogram (EHG) caused by nifedipine in women with preterm contractions. Methods. Calculation of the PSD peak frequency in EHG contraction bursts at different times of nifedipine treatment in women in gestational age 24 to 32 weeks with ...
Neto Osmar Pinto - - 2010
Rectification of EMG signals is a common processing step used when performing electroencephalographic-electromyographic (EEG-EMG) coherence and EMG-EMG coherence. It is well known, however, that EMG rectification alters the power spectrum of the recorded EMG signal (interference EMG). The purpose of this study was to determine whether rectification of the EMG ...
Klein Cliff S - - 2010
Few studies have quantified lower limb muscle activity over 24 h using electromyographic signals (EMG). None have described the changes in EMG duration and intensity when data are analyzed with different thresholds. Continuous bilateral EMG recordings were made from vastus lateralis (VL) in 10 subjects (20-48 yr) for 24 h. ...
Chen Xinpu - - 2010
This paper presents a discriminant bispectrum (DBS) feature extraction approach to surface electromyogram (sEMG) signal classification for prosthetic control. The proposed feature extraction method involves two steps: (1) the bispectrum matrix integration, and (2) the Fisher linear discriminant (FLD) projection. We compare DBS with other conventional features, such as autoregressive ...
Svendsen Jacob H - - 2010
The aim of this study was to investigate the effect of gender differences on force variability as assessed by means of linear and nonlinear estimators during short duration, ramp and sustained isometric elbow flexions. Ten males and ten females performed elbow flexion receiving visual feedback from the direction of force ...
Magalhães Fernando Henrique - - 2009
The main questions addressed in this work were whether and how adaptation to suppression of visual information occurs in a free-fall paradigm, and the extent to which vision availability influences the control of landing movements. The prelanding modulation of EMG timing and amplitude of four lower-limb muscles was investigated. Participants ...
Arabadzhiev Todor I - - 2010
The increase in muscle strength without noticeable hypertrophic adaptations is very important in some sports. Motor unit (MU) synchronisation and higher rate of MU activation are proposed as possible mechanisms for such a strength and electromyogram (EMG) increase in the early phase of a training regimen. Root mean square and/or ...
Arslan Yunus Ziya - - 2010
In this work, a new signal processing method was proposed in order to predict externally applied forces to human hands by deriving a relationship between the surface electromyographic (SEMG) signals and experimentally known forces. This relationship was investigated by analyzing the spectral features of the SEMG signals. SEMG signals were ...
Kamavuako Ernest Nlandu - - 2009
The surface electromyographic (sEMG) signal can be used for force prediction and control in prosthetic devices. Because of technological advances on implantable sensors, the use of intramuscular EMG (iEMG) is becoming a potential alternative to sEMG for the control of multiple degrees-of-freedom (DOF). An invasive system is not affected by ...
Boonstra Tjeerd W - - 2009
Using electroencephalography (EEG) and electromyography (EMG), corticomuscular and bilateral motor unit synchronization have been found in different frequency bands and under different task conditions. These different types of long-range synchrony are hypothesized to originate from distinct mechanisms. We tested this by comparing time-resolved EEG-EMG and EMG-EMG coherence in a bilateral ...
Holtermann A - - 2010
The aim of this study was to investigate the importance of duration of differential activations between the heads of the biceps brachii on local fatigue during prolonged low-level contractions. Fifteen subjects carried out isometric elbow flexion at 5% of maximal voluntary contraction (MVC) for 30 min. MVCs were performed before ...
Pain Matthew T G - - 2009
The origin of the well-documented discrepancy between maximum voluntary and in vitro tetanic eccentric strength has yet to be fully understood. This study aimed to determine whether surface EMG measurements can be used to reproduce the in vitro tetanic force-velocity relationship from maximum voluntary contractions. Five subjects performed maximal knee ...
Altenburg T M - - 2009
Single motor unit electromyographic (EMG) activity of the knee extensors was investigated at different knee angles with subjects (n = 10) exerting the same absolute submaximal isometric torque at each angle. Measurements were made over a 20 degrees range around the optimum angle for torque production (AngleTmax) and, where feasible, ...
Blackburn Marcus K MK Department of Ophthalmology and Visual Sciences, John A. Moran Eye Center, University of Utah Health Sciences Center, 65 Mario Capecchi Drive, Salt Lake City, UT 94132, - - 2009
The objective of these 2 studies was to assess the efficacy of FL-41-tinted lenses in the treatment of benign essential blepharospasm (BEB). A randomized crossover study and a randomized crossover case-control study. The first study included 30 subjects with BEB. The second study included 26 subjects with BEB and 26 ...
Ishida H - - 2009
We often observe when workers lift objects, they tend to move their heads upward and back. Their movement may be an efficient habit, but little is known about control of the head while lifting. Our primary aim was to investigate the hypothesis that several repetitive liftings would lead to an ...
Kamimura Takashi - - 2009
The effects of isometric antagonist conditioning contraction (ACC) at various durations and intensities on the contractile force, electromyographic (EMG) amplitude, and their rates of rise of elbow flexor muscles were examined in healthy participants. In particular, we focused on the change in the maximum rate of initial force development of ...
Eswaran Hari H Department of Obstetrics and Gynecology, University of Arkansas for Medical Sciences, 4301 W. Markham Slot 518, Little Rock, AR 72205, USA. - - 2009
The objective was to extract, quantify and characterize the uterine magnetomyographic (MMG) signals that correspond to the electrophysiological activity of the uterus. Transabdominal MMG recordings with high spatial-temporal resolution were performed with the use of the 151 non-invasive magnetic sensor system. The extraction, quantification and characterization procedures were developed and ...
Beck Travis W - - 2009
The purpose of this study was to compare the monopolar electromyographic (EMG) amplitude versus isometric force relationships from three signal processing methods (raw versus notch filtering versus adaptive filtering). Seventeen healthy subjects (mean+/-SD age=24.6+/-4.3 yr) performed incremental isometric muscle actions of the dominant leg extensors in 10% increments from 10% ...
Pope Kenneth J - - 2009
We recorded scalp electrical activity before and after full neuro-muscular paralysis in 5 volunteers and determined differences due to elimination of muscular activity on several standard applications of EEG. Due to paralysis, there were reductions in 'noisiness' of the standard scalp recordings which were maximal over the peripheral scalp, not ...
Holobar Ales - - 2009
OBJECTIVE: We systematically tested the capability of the Convolution Kernel Compensation (CKC) method to identify motor unit (MU) discharge patterns from the simulated and experimental surface electromyogram (sEMG) during low-force contractions. METHODS: sEMG was detected with a grid of 13 x 5 electrodes. In simulated signals with 20 dB signal-to-noise ...
Xiao Weijun W Department of Electrical, Computer, and Biomedical Engineering, Kingston, RI 02881, - - 2009
Applying electromyographic (EMG) signal pattern recognition to artificial leg control is challenging because leg EMGs are non-stationary. Time-frequency features are suitable for representing non-stationary signals; however, the computational complexity to extract time-frequency features is too high and current embedded systems used for artificial limb control are inadequate for real-time computing. ...
Nawab S Hamid SH Electrical and Computer Engineering and Biomedical Engineering Departments and NeuroMuscular Research Center of Boston University, Boston, MA 02215, USA. - - 2009
We introduce the concept of empirically sustainable principles for biosignal separation as a means of addressing the complexities that are practically encountered in the decomposition of surface electromyographic (sEMG) signals. Recently, we have identified two new principles of this type. The first principle places upper bounds on the inter-firing intervals ...
Tillin Neale Anthony - - 2009
Post-activation potentiation (PAP) is induced by a voluntary conditioning contraction (CC), performed typically at a maximal or near-maximal intensity, and has consistently been shown to increase both peak force and rate of force development during subsequent twitch contractions. The proposed mechanisms underlying PAP are associated with phosphorylation of myosin regulatory ...
Zhang X - - 2009
The onset detection of muscle activation is an essential issue in electromyogram (EMG) control. In this paper, a novel approach based on EMG power with automatic adaptive threshold is proposed to address this issue. The purpose is to develop an effective EMG-controlled meal assistance robot. Taking into account the individual ...
Nielsen Johnny L G JL Center for Sensory-Motor Interaction (SMI), Department of Health Science and Technology, Aalborg University, 9220 Aalborg, - - 2009
A new signal processing scheme is presented for extracting neural control information from the multi-channel surface electromyographic signal (sEMG). The extracted information can be used to proportionally control a multi-degree of freedom (DOF) prosthesis. Four time-domain (TD) features were extracted from the multi-channel sEMG during a series of anisotonic, isometric ...
Kita Kahori K University of Tokyo, Tokyo 1138656, Japan. - - 2009
In order to control a myoelectric hand, it is necessary to discriminate among motions using electromyography (EMG) signals. One of the biggest problems in doing so is that EMG feature patterns of different motions overlap, and a classifier cannot discriminate clearly between them. Therefore, we propose a motion discrimination method ...
Verma P K - - 2009
Acetylcholine is the major endogenous classical neurotransmitter in the central and peripheral nervous system of trematodes and mammals. This study investigates the effects of cholinergic drugs on muscle activity in the amphistome, Gastrothylax crumenifer. In the present investigation, acetylcholine (10- 7-10- 3 m) did not produce any marked effect, whereas ...
Minetto M A - - 2009
OBJECTIVES: To examine if different frequencies of electrical stimulation trigger different sized cramps in the abductor hallucis muscle and to analyze their surface electromyographic (EMG) behaviour in both time and frequency domains. METHODS: Fifteen subjects were studied. Stimulation trains of 150 pulses were applied to the muscle motor point. Frequency ...
Kiemel Tim T Department of Kinesiology, University of Maryland, College Park, MD 20742, USA. - - 2008
We determined properties of the plant during human upright stance using a closed-loop system identification method originally applied to human postural control by another group. To identify the plant, which was operationally defined as the mapping from muscle activation (rectified EMG signals) to body segment angles, we rotated the visual ...
Williams Matthew R - - 2008
We investigated the performance of three user interfaces for restoration of cursor control in individuals with tetraplegia: head orientation, electromyography (EMG) from face and neck muscles, and a standard computer mouse (for comparison). Subjects engaged in a 2-D, center-out, Fitts' Law style task and performance was evaluated using several measures. ...
Fujisawa Takuya - - 2008
Skills in controlling drumsticks correctly and appropriately in drumming are required to play rhythms without mistakes at appropriate dynamic levels of sound. Results obtained by analyzing drummers' movements from visual information, such as motion captures or camera recordings, have been reported in past studies, but analysis using biological information has ...
Kukulka C G CG Program in Physical Therapy, University of Minnesota, Minneapolis, MN, USA. - - 2009
The effects of a cutaneous imperative stimulus trigger cue (sural nerve stimulation) versus visual cuing of rapid step initiation were assessed in young, healthy subjects (n = 18). Two sets of experiments were conducted in which the vertical ground reaction force and EMG in tibialis anterior (TA) and gluteus medius ...
Laufer Yocheved - - 2008
BACKGROUND: Low-frequency pulsed currents (LPCs) and kilohertz-frequency alternating currents (KACs) are used clinically to augment muscle contractions. Treatment effectiveness may be enhanced by selecting stimulation parameters that evoke the strongest contractions with minimal discomfort and fatigue. OBJECTIVE: The objective of this study was to compare maximally induced strength (force-producing capacity) ...
Hug François - - 2008
The aim of this study was to determine whether high inter-individual variability of the electromyographic (EMG) patterns during pedaling is accompanied by variability in the pedal force application patterns. Eleven male experienced cyclists were tested at two submaximal power outputs (150 and 250 W). Pedal force components (effective and total ...
Filho Eddie B L - - 2008
In this paper, the multidimensional multiscale parser (MMP) is employed for encoding electromyographic signals. The experiments were carried out with real signals acquired in laboratory and show that the proposed scheme is effective, outperforming even wavelet-based state-of-the-art schemes present in the literature in terms of percent root mean square difference ...
Kouzaki Motoki - - 2008
The purpose of the present study was to determine whether the frequency features of the MMG signals during quiet standing reflect body sway as well as recurring muscle activity. Twenty healthy men maintained quiet standing in a barefoot position with their eyes open or closed. During quiet standing, MMG detected ...
Riley Zachary A - - 2008
Bursts of activity in the surface electromyogram (EMG) during a sustained contraction have been interpreted as corresponding to the transient recruitment of motor units, but this association has never been confirmed. The current study compared the timing of trains of action potentials discharged by single motor units during a sustained ...
Beck Travis W - - 2009
The purpose of this study was to use a wavelet-based signal processing technique to examine the influence of electrode placement over the innervation zone (IZ) on the shape of the electromyographic (EMG) frequency spectrum. Ten healthy males (mean+/-SD age=23.6+/-3.0 years) performed isometric muscle actions of the dominant leg extensors at ...
Farina Dario - - 2008
The study presents analytical, simulation, and experimental analyses of amplitude cancellation of motor-unit action potentials (APs) in the interference electromyogram (EMG) and its relation to the size of the spike-triggered average (STA) EMG. The amount of cancellation of motor-unit APs decreases monotonically as a function of the ratio between the ...
Kawashima Noritaka - - 2008
Direct evidence supporting the contribution of upper limb motion on the generation of locomotive motor output in humans is still limited. Here, we aimed to examine the effect of upper limb motion on locomotor-like muscle activities in the lower limb in persons with spinal cord injury (SCI). By imposing passive ...
Kaya Motoshi - - 2008
It has been shown that cat soleus (SOL) forces remain nearly constant despite increases in electromyography (EMG) activity for increasing speeds of locomotion, while medial gastrocnemius (MG) forces and EMG activity increase in parallel. Furthermore, during jumping, average cat SOL forces decrease, while average EMG activity increases dramatically compared with ...
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