WorldWideScience

Sample records for electric stimulation accelerates

  1. Transcutaneous electrical nerve stimulation (TENS) accelerates cutaneous wound healing and inhibits pro-inflammatory cytokines.

    Science.gov (United States)

    Gürgen, Seren Gülşen; Sayın, Oya; Cetin, Ferihan; Tuç Yücel, Ayşe

    2014-06-01

    The purpose of this study was to evaluate transcutaneous electrical nerve stimulation (TENS) and other common treatment methods used in the process of wound healing in terms of the expression levels of pro-inflammatory cytokines. In the study, 24 female and 24 male adult Wistar-Albino rats were divided into five groups: (1) the non-wounded group having no incision wounds, (2) the control group having incision wounds, (3) the TENS (2 Hz, 15 min) group, (4) the physiological saline (PS) group and (5) the povidone iodine (PI) group. In the skin sections, interleukin-1 beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-α (TNF-α) were assessed with enzyme-linked immunosorbent assay and immunohistochemical methods. In the non-wounded group, the expression of IL-1β, IL-6, and TNF-α signaling molecules was weaker in the whole tissue; however, in the control group, significant inflammatory response occurred, and strong cytokine expression was observed in the dermis, granulation tissue, hair follicles, and sebaceous glands (P TENS group, the decrease in TNF-α, IL-1β, and IL-6 immunoreaction in the skin was significant compared to the other forms of treatment (P TENS group suggest that TENS shortened the healing process by inhibating the inflammation phase.

  2. Electrical stimulation accelerates nerve regeneration and functional recovery in delayed peripheral nerve injury in rats.

    Science.gov (United States)

    Huang, Jinghui; Zhang, Yongguang; Lu, Lei; Hu, Xueyu; Luo, Zhuojing

    2013-12-01

    The present study aims to investigate the potential of brief electrical stimulation (ES; 3 V, 20 Hz, 20 min) in improving functional recovery in delayed nerve injury repair (DNIR). The sciatic nerve of Sprague Dawley rats was transected, and the repair of nerve injury was delayed for different time durations (2, 4, 12 and 24 weeks). Brief depolarizing ES was applied to the proximal nerve stump when the transected nerve stumps were bridged with a hollow nerve conduit (5 mm in length) after delayed periods. We found that the diameter and number of regenerated axons, the thickness of myelin sheath, as well as the number of Fluoro-Gold retrograde-labeled motoneurons and sensory neurons were significantly increased by ES, suggesting that brief ES to proximal nerve stumps is capable of promoting nerve regeneration in DNIR with different delayed durations, with the longest duration of 24 weeks. In addition, the amplitude of compound muscle action potential (gastrocnemius muscle) and nerve conduction velocity were also enhanced, and gastrocnemius muscle atrophy was partially reversed by brief ES, indicating that brief ES to proximal nerve stump was able to improve functional recovery in DNIR. Furthermore, brief ES was capable of increasing brain-derived neurotrophic factor (BDNF) expression in the spinal cord in DNIR, suggesting that BDNF-mediated neurotrophin signaling might be one of the contributing factors to the beneficial effect of brief ES on DNIR. In conclusion, the present findings indicate the potential of using brief ES as a useful method to improve functional recovery for delayed repair of peripheral nerve lesions. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  3. Patient-Specific Electric Field Simulations and Acceleration Measurements for Objective Analysis of Intraoperative Stimulation Tests in the Thalamus.

    Science.gov (United States)

    Hemm, Simone; Pison, Daniela; Alonso, Fabiola; Shah, Ashesh; Coste, Jérôme; Lemaire, Jean-Jacques; Wårdell, Karin

    2016-01-01

    Despite an increasing use of deep brain stimulation (DBS) the fundamental mechanisms of action remain largely unknown. Simulation of electric entities has previously been proposed for chronic DBS combined with subjective symptom evaluations, but not for intraoperative stimulation tests. The present paper introduces a method for an objective exploitation of intraoperative stimulation test data to identify the optimal implant position of the chronic DBS lead by relating the electric field (EF) simulations to the patient-specific anatomy and the clinical effects quantified by accelerometry. To illustrate the feasibility of this approach, it was applied to five patients with essential tremor bilaterally implanted in the ventral intermediate nucleus (VIM). The VIM and its neighborhood structures were preoperatively outlined in 3D on white matter attenuated inversion recovery MR images. Quantitative intraoperative clinical assessments were performed using accelerometry. EF simulations (n = 272) for intraoperative stimulation test data performed along two trajectories per side were set-up using the finite element method for 143 stimulation test positions. The resulting EF isosurface of 0.2 V/mm was superimposed to the outlined anatomical structures. The percentage of volume of each structure's overlap was calculated and related to the corresponding clinical improvement. The proposed concept has been successfully applied to the five patients. For higher clinical improvements, not only the VIM but as well other neighboring structures were covered by the EF isosurfaces. The percentage of the volumes of the VIM, of the nucleus intermediate lateral of the thalamus and the prelemniscal radiations within the prerubral field of Forel increased for clinical improvements higher than 50% compared to improvements lower than 50%. The presented new concept allows a detailed and objective analysis of a high amount of intraoperative data to identify the optimal stimulation target. First

  4. Brief post-surgical electrical stimulation accelerates axon regeneration and muscle reinnervation without affecting the functional measures in carpal tunnel syndrome patients.

    Science.gov (United States)

    Gordon, Tessa; Amirjani, Nasim; Edwards, David C; Chan, K Ming

    2010-05-01

    Electrical stimulation (ES) of injured peripheral nerves accelerates axonal regeneration in laboratory animals. However, clinical applicability of this intervention has never been investigated in human subjects. The aim of this pilot study was to determine the effect of ES on axonal regeneration after surgery in patients with median nerve compression in the carpal tunnel causing marked motor axonal loss. A randomized control trial was conducted to provide proof of principle for ES-induced acceleration of axon regeneration in human patients. Carpel tunnel release surgery (CTRS) was performed and in the stimulation group of patients, stainless steel electrode wires placed alongside the median nerve proximal to the surgical decompression site for immediate 1 h 20 Hz bipolar ES. Subjects were followed for a year at regular intervals. Axonal regeneration was quantified using motor unit number estimation (MUNE) and sensory and motor nerve conduction studies. Purdue Pegboard Test, Semmes Weinstein Monofilaments, and Levine's Self-Assessment Questionnaire were used to assess functional recovery. The stimulation group had significant axonal regeneration 6-8 months after the CTRS when the MUNE increased to 290+/-140 (mean+/-SD) motor units (MU) from 150+/-62 MU at baseline (p0.2). Terminal motor latency significantly accelerated in the stimulation group but not the control group (p>0.1). Sensory nerve conduction values significantly improved in the stimulation group earlier than the controls. Other outcome measures showed a significant improvement in both patient groups. We conclude that brief low frequency ES accelerates axonal regeneration and target reinnervation in humans. Copyright 2009 Elsevier Inc. All rights reserved.

  5. Electrical stimulation in exercise training

    Science.gov (United States)

    Kroll, Walter

    1994-01-01

    Electrical stimulation has a long history of use in medicine dating back to 46 A.D. when the Roman physician Largus found the electrical discharge of torpedo fishes useful in the treatment of pain produced by headache and gout. A rival Greek physician, Dioscorides, discounted the value of the torpedo fish for headache relief but did recommend its use in the treatment of hemorrhoids. In 1745, the Leyden jar and various sized electrostatic generators were used to treat angina pectoris, epilepsy, hemiplegia, kidney stones, and sciatica. Benjamin Franklin used an electrical device to treat successfully a young woman suffering from convulsive fits. In the late 1800's battery powered hydroelectric baths were used to treat chronic inflammation of the uterus while electrified athletic supporters were advertised for the treatment of male problems. Fortunately, such an amusing early history of the simple beginnings of electrical stimulation did not prevent eventual development of a variety of useful therapeutic and rehabilitative applications of electrical stimulation. Over the centuries electrical stimulation has survived as a modality in the treatment of various medical disorders with its primary application being in the rehabilitation area. Recently, a surge of new interest in electrical stimulation has been kindled by the work of a Russian sport scientist who reported remarkable muscle strength and endurance improvements in elite athletes. Yakov Kots reported his research on electric stimulation and strength improvements in 1977 at a Canadian-Soviet Exchange Symposium held at Concordia University in Montreal. Since then an explosion of new studies has been seen in both sport science and in medicine. Based upon the reported works of Kots and the present surge of new investigations, one could be misled as to the origin of electrical stimulation as a technique to increase muscle strength. As a matter of fact, electric stimulation has been used as a technique to improve

  6. Transcranial electrical stimulation: An introduction

    CERN Document Server

    Tarazona, Carlos G; Chávez, Laura; Andrade, Sebastián

    2015-01-01

    The main objective of the electrical stimulation of the brain is to generate action potentials from the application of electromagnetic fields. Among the available techniques, transcranial electrical stimulation (TES) represents a popular method of administration that has the advantage of being non-invasive and economically more affordable. This article aims to briefly introduce the reader into the understanding of TES in terms of the physics involved as well as for some of the relevant results of studies applying this technique.

  7. Gastric Electrical Stimulation

    Science.gov (United States)

    2006-01-01

    Executive Summary Objective The objective of this analysis was to assess the effectiveness, safety and cost-effectiveness of gastric electrical stimulation (GES) for the treatment of chronic, symptomatic refractory gastroparesis and morbid obesity. Background Gastroparesis - Epidemiology Gastroparesis (GP) broadly refers to impaired gastric emptying in the absence of obstruction. Clinically, this can range from the incidental detection of delayed gastric emptying in an asymptomatic person to patients with severe nausea, vomiting and malnutrition. Symptoms of GP are nonspecific and may mimic structural disorders such as ulcer disease, partial gastric or small bowel obstruction, gastric cancer, and pancreaticobiliary disorders. Gastroparesis may occur in association with diabetes, gastric surgery (consequence of peptic ulcer surgery and vagotomy) or for unknown reasons (idiopathic gastroparesis). Symptoms include early satiety, nausea, vomiting, abdominal pain and weight loss. The majority of patients with GP are women. The relationship between upper gastrointestinal symptoms and the rate of gastric emptying is considered to be weak. Some patients with markedly delayed gastric emptying are asymptomatic and sometimes, severe symptoms may remit spontaneously. Idiopathic GP may represent the most common form of GP. In one tertiary referral retrospective series, the etiologies in 146 GP patients were 36% idiopathic, 29% diabetic, 13% postgastric surgery, 7.5% Parkinson’s disease, 4.8% collagen vascular disorders, 4.1% intestinal pseudoobstruction and 6% miscellaneous causes. The true prevalence of digestive symptoms in patients with diabetes and the relationship of these symptoms to delayed gastric emptying are unknown. Delayed gastric emptying is present in 27% to 58% of patients with type 1 diabetes and 30% with type 2 diabetes. However, highly variable rates of gastric emptying have been reported in type 1 and 2 diabetes, suggesting that development of GP in

  8. Evoked Electromyographically Controlled Electrical Stimulation

    Directory of Open Access Journals (Sweden)

    Mitsuhiro Hayashibe

    2016-07-01

    Full Text Available Time-variant muscle responses under electrical stimulation (ES are often problematic for all the applications of neuroprosthetic muscle control. This situation limits the range of ES usage in relevant areas, mainly due to muscle fatigue and also to changes in stimulation electrode contact conditions, especially in transcutaneous ES. Surface electrodes are still the most widely used in noninvasive applications.Electrical field variations caused by changes in the stimulation contact condition markedly affect the resulting total muscle activation levels. Fatigue phenomena under functional electrical stimulation (FES are also well known source of time-varying characteristics coming from muscle response under ES. Therefore it is essential to monitor the actual muscle state and assess the expected muscle response by ES so as to improve the current ES system in favour of adaptive muscle-response-aware FES control. To deal with this issue, we have been studying a novel control technique using evoked electromyography (eEMG signals to compensate for these muscle time-variances under ES for stable neuroprosthetic muscle control. In this perspective article, I overview the background of this topic and highlight important points to be aware of when using ES to induce the desired muscle activation regardless of the time-variance. I also demonstrate how to deal with the common critical problem of ES to move toward robust neuroprosthetic muscle control with the Evoked Electromyographically Controlled Electrical Stimulation paradigm.

  9. Low intensity transcranial electric stimulation

    DEFF Research Database (Denmark)

    Antal, A.; Alekseichuk, I.; Bikson, M.

    2017-01-01

    Low intensity transcranial electrical stimulation (TES) in humans, encompassing transcranial direct current (tDCS), transcutaneous spinal Direct Current Stimulation (tsDCS), transcranial alternating current (tACS), and transcranial random noise (tRNS) stimulation or their combinations, appears...... to suboptimal electrode-skin contact. Very rarely mania or hypomania was induced in patients with depression (11 documented cases), yet a causal relationship is difficult to prove because of the low incidence rate and limited numbers of subjects in controlled trials. Mild AEs (MAEs) include headache and fatigue...

  10. Influence of electrical stimulation on carcass and meat quality of ...

    African Journals Online (AJOL)

    Agbeniga

    2014-08-24

    Aug 24, 2014 ... In addition to the accelerated glycolysis caused by electrical stimulation to lower the. pH of carcasses after slaughter, stress before or at slaughter could also play a part in lowering the pH and stimulating proteolysis and gluconeogenesis by the secretion of corticosteroid hormones. Carcasses from ...

  11. Braille line using electrical stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Puertas, A; Pures, P; Echenique, A M; Ensinck, J P Graffigna y G [Gabinete de TecnologIa Medica. Universidad N. de San Juan (Argentina)

    2007-11-15

    Conceived within the field of Rehabilitation Technologies for visually impaired persons, the present work aims at enabling the blind user to read written material by means of a tactile display. Once he is familiarized to operate this system, the user will be able to achieve greater performance in study, academic and job activities, thus achieving a rapid and easier social inclusion. The devise accepts any kind of text that is computer-loadable (documents, books, Internet information, and the like) which, through digital means, can be read as Braille text on the pad. This tactile display is composed of an electrodes platform that simulate, through stimulation the writing/reading Braille characters. In order to perceive said characters in similar way to the tactile feeling from paper material, the skin receptor of fingers are stimulated electrically so as to simulate the same pressure and depressions as those of the paper-based counterpart information. Once designed and developed, the display was tested with blind subjects, with relatively satisfactory results. As a continuing project, this prototype is currently being improved as regards.

  12. Braille line using electrical stimulation

    Science.gov (United States)

    Puertas, A.; Purés, P.; Echenique, A. M.; Ensinck, J. P. Graffigna y. G.

    2007-11-01

    Conceived within the field of Rehabilitation Technologies for visually impaired persons, the present work aims at enabling the blind user to read written material by means of a tactile display. Once he is familiarized to operate this system, the user will be able to achieve greater performance in study, academic and job activities, thus achieving a rapid and easier social inclusion. The devise accepts any kind of text that is computer-loadable (documents, books, Internet information, and the like) which, through digital means, can be read as Braille text on the pad. This tactile display is composed of an electrodes platform that simulate, through stimulation the writing/reading Braille characters. In order to perceive said characters in similar way to the tactile feeling from paper material, the skin receptor of fingers are stimulated electrically so as to simulate the same pressure and depressions as those of the paper-based counterpart information. Once designed and developed, the display was tested with blind subjects, with relatively satisfactory results. As a continuing project, this prototype is currently being improved as regards.

  13. Does electrical stimulation enhance post-exercise performance recovery?

    Science.gov (United States)

    Babault, Nicolas; Cometti, Carole; Maffiuletti, Nicola A; Deley, Gaëlle

    2011-10-01

    Elite sport requires high-volume and high-intensity training that inevitably induces neuromuscular fatigue detrimental for physical performance. Improving recovery processes is, therefore, fundamental and to this, a wide variety of recovery modalities could be proposed. Among them, neuromuscular electrical stimulation is largely adopted particularly by endurance-type and team sport athletes. This type of solicitation, when used with low stimulation frequencies, induces contractions of short duration and low intensity comparable to active recovery. This might be of interest to favour muscle blood flow and therefore metabolites washout to accelerate recovery kinetics during and after fatiguing exercises, training sessions or competition. However, although electrical stimulation is often used for recovery, limited evidence exists regarding its effects for an improvement of most physiological variables or reduced subjective rating of muscle soreness. Therefore, the main aim of this brief review is to present recent results from the literature to clarify the effectiveness of electrical stimulation as a recovery modality.

  14. Classification of electrical discharges in DC Accelerators

    Energy Technology Data Exchange (ETDEWEB)

    Banerjee, Srutarshi, E-mail: sruban.stephens@gmail.com [Accelerator and Pulse Power Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Deb, A.K. [Department of Electrical Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India); Rajan, Rehim N. [Accelerator and Pulse Power Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India); Kishore, N.K. [Department of Electrical Engineering, Indian Institute of Technology Kharagpur, Kharagpur 721302 (India)

    2016-08-11

    Controlled electrical discharge aids in conditioning of the system while uncontrolled discharges damage its electronic components. DC Accelerator being a high voltage system is no exception. It is useful to classify electrical discharges according to the severity. Experimental prototypes of the accelerator discharges are developed. Photomultiplier Tubes (PMTs) are used to detect the signals from these discharges. Time and Frequency domain characteristics of the detected discharges are used to extract features. Machine Learning approaches like Fuzzy Logic, Neural Network and Least Squares Support Vector Machine (LSSVM) are employed to classify the discharges. This aids in detecting the severity of the discharges.

  15. Classification of electrical discharges in DC Accelerators

    Science.gov (United States)

    Banerjee, Srutarshi; Deb, A. K.; Rajan, Rehim N.; Kishore, N. K.

    2016-08-01

    Controlled electrical discharge aids in conditioning of the system while uncontrolled discharges damage its electronic components. DC Accelerator being a high voltage system is no exception. It is useful to classify electrical discharges according to the severity. Experimental prototypes of the accelerator discharges are developed. Photomultiplier Tubes (PMTs) are used to detect the signals from these discharges. Time and Frequency domain characteristics of the detected discharges are used to extract features. Machine Learning approaches like Fuzzy Logic, Neural Network and Least Squares Support Vector Machine (LSSVM) are employed to classify the discharges. This aids in detecting the severity of the discharges.

  16. [Apparatus "Stimul-1" foe electric stimulation of muscles].

    Science.gov (United States)

    Andrianova, G G; Prokopenko, G I; Shabashevich, L B; Khvostov, L N

    1977-01-01

    The apparatus "Stimul-1" has been designed and recommended for batch production, its purpose being broad application in the medical practice of electrical stimulation of the muscles. For stimulation is used sinusoidal a.c. current with frequency of 2 kHz, which produces and effective contraction of the muscles without causing any sensation of pain. The unit is constructed by using up-to-date components, including microminiature logic circuits, operational amplifiers and field-effect transistors.

  17. Mimicking muscle activity with electrical stimulation

    Science.gov (United States)

    Johnson, Lise A.; Fuglevand, Andrew J.

    2011-02-01

    Functional electrical stimulation is a rehabilitation technology that can restore some degree of motor function in individuals who have sustained a spinal cord injury or stroke. One way to identify the spatio-temporal patterns of muscle stimulation needed to elicit complex upper limb movements is to use electromyographic (EMG) activity recorded from able-bodied subjects as a template for electrical stimulation. However, this requires a transfer function to convert the recorded (or predicted) EMG signals into an appropriate pattern of electrical stimulation. Here we develop a generalized transfer function that maps EMG activity into a stimulation pattern that modulates muscle output by varying both the pulse frequency and the pulse amplitude. We show that the stimulation patterns produced by this transfer function mimic the active state measured by EMG insofar as they reproduce with good fidelity the complex patterns of joint torque and joint displacement.

  18. Neural adaptations to electrical stimulation strength training

    NARCIS (Netherlands)

    Hortobagyi, Tibor; Maffiuletti, Nicola A.

    2011-01-01

    This review provides evidence for the hypothesis that electrostimulation strength training (EST) increases the force of a maximal voluntary contraction (MVC) through neural adaptations in healthy skeletal muscle. Although electrical stimulation and voluntary effort activate muscle differently, there

  19. [Novel functional electrical stimulation for neurorehabilitation].

    Science.gov (United States)

    Hara, Yukihiro

    2010-02-01

    Our understanding of motor learning, neuroplasticity, and functional recovery after the occurrence of brain lesions has increased considerably. New findings in basic neuroscience have provided an impetus for research in motor rehabilitation. Several prospective studies have shown that repeated motor practice and motor activity in a real world environment have a favorable effect on motor recovery in stroke patients. Electrical stimulation can be applied in a variety of ways to the hemiparetic upper extremity following a stroke. In particular, electromyography (EMG)-triggered electrical muscle stimulation improves the motor function of the hemiparetic arm and hand. Triggered electrical stimulation is reported to be more effective than non-triggered electrical stimulation in facilitating upper extremity motor recovery after stroke. Power-assisted functional electrical stimulation (FES) induces greater muscle contraction by electrical stimulation that is in proportion to voluntary integrated EMG signals. Daily power-assisted FES home-program therapy with novel equipment has been shown to effectively improve wrist, finger extension, and shoulder flexion. Combined modulation of voluntary movement, proprioceptive sensory feedback, and electrical stimulation might play an important role in improving impaired sensory-motor integration by power-assisted FES therapy. A multi-channel near-infrared spectroscopy (NIRS) studies in which the hemoglobin levels in the brain were non-invasively and dynamically measured during functional activity found that the cerebral blood flow in the injured sensory-motor cortex area is greater during a power-assisted FES session than during simple active movement or simple electrical stimulation. A novel power-assisted FES sleeve (Cyberhand) has been developed for the rehabilitation of hemiplegic upper extremities.

  20. Gastric applications of electrical field stimulation.

    LENUS (Irish Health Repository)

    Hogan, Aisling M

    2012-02-01

    Advances in clinical applications of electricity have been vast since the launch of Hayman\\'s first cardiac pacemaker more than 70 years ago. Gastric electrical stimulation devices have been recently licensed for treatment of gastroparesis and preliminary studies examining their potential for use in refractory obesity yield promising results.

  1. Cortical excitability changes following grasping exercise augmented with electrical stimulation

    DEFF Research Database (Denmark)

    Barsi, Gergely Istvan; Popovic, Dejan B.; Tarkka, Ina M.

    2008-01-01

    ) functional electrical stimulation (FES) of the finger flexors and extensors, (2) voluntary movement (VOL) with sensory stimulation, and (3) therapeutic FES (TFES) where the electrical stimulation augmented voluntary activation. TFES training produced a significant increase in MEP magnitude throughout...

  2. The Accelerated Procedure for Electrical Work (TPA)

    CERN Document Server

    Coelingh, G J

    2000-01-01

    The accelerated procedure for electrical work [in French: Travaux électriques selon Procédure Accélérée (TPA)] was introduced in October 1996. It allows the contractor to carry out minor electrical installation jobs (about 350 a year) independently. The special features of the TPA are that the number of hours to be worked is limited to 16 and the cost to less than 1000 CHF. This procedure has substantial advantages for both the requesters and ST division. Firstly, the requester benefits from direct contact with the contractor, prompt action and simplified invoicing. In addition, ST division, relieved of ordinary minor work, can concentrate on larger-scale projects and can take advantage of a simplified system of administration. The author sets out the course of the procedure, its advantages and drawbacks, the statistics and the results of a satisfaction questionnaire. This procedure could be adapted and extended to other operations linked to future contracts.

  3. Binaural hearing with electrical stimulation.

    Science.gov (United States)

    Kan, Alan; Litovsky, Ruth Y

    2015-04-01

    Bilateral cochlear implantation is becoming a standard of care in many clinics. While much benefit has been shown through bilateral implantation, patients who have bilateral cochlear implants (CIs) still do not perform as well as normal hearing listeners in sound localization and understanding speech in noisy environments. This difference in performance can arise from a number of different factors, including the areas of hardware and engineering, surgical precision and pathology of the auditory system in deaf persons. While surgical precision and individual pathology are factors that are beyond careful control, improvements can be made in the areas of clinical practice and the engineering of binaural speech processors. These improvements should be grounded in a good understanding of the sensitivities of bilateral CI patients to the acoustic binaural cues that are important to normal hearing listeners for sound localization and speech in noise understanding. To this end, we review the current state-of-the-art in the understanding of the sensitivities of bilateral CI patients to binaural cues in electric hearing, and highlight the important issues and challenges as they relate to clinical practice and the development of new binaural processing strategies. This article is part of a Special Issue entitled . Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Binaural hearing with electrical stimulation

    Science.gov (United States)

    Kan, Alan; Litovsky, Ruth Y.

    2014-01-01

    Bilateral cochlear implantation is becoming a standard of care in many clinics. While much benefit has been shown through bilateral implantation, patients who have bilateral cochlear implants (CIs) still do not perform as well as normal hearing listeners in sound localization and understanding speech in noisy environments. This difference in performance can arise from a number of different factors, including the areas of hardware and engineering, surgical precision and pathology of the auditory system in deaf persons. While surgical precision and individual pathology are factors that are beyond careful control, improvements can be made in the areas of clinical practice and the engineering of binaural speech processors. These improvements should be grounded in a good understanding of the sensitivities of bilateral CI patients to the acoustic binaural cues that are important to normal hearing listeners for sound localization and speech in noise understanding. To this end, we review the current state-of-the-art in the understanding of the sensitivities of bilateral CI patients to binaural cues in electric hearing, and highlight the important issues and challenges as they relate to clinical practice and the development of new binaural processing strategies. PMID:25193553

  5. Wireless control of functional electrical stimulation systems.

    Science.gov (United States)

    Matjacić, Z; Munih, M; Bajd, T; Kralj, A; Benko, H; Obreza, P

    1997-03-01

    With the assistance of crutches and functional electrical stimulation (FES), we are able to restore standing and simple gait in some spinal cord injured (SCI) patients. In present rehabilitative systems, the patient divides the gait cycle into stance and swing phases via pushbuttons mounted on the handles of the crutches, which are hardwired to the functional electrical stimulator. The surface-mount technology based telemetry system, which makes use of the radiofrequency medium at 40 MHz, was developed to provide wireless control of the FES system. Signals from crutch pushbuttons were coded and transferred from the transmitter to the receiver. The receiver was firmly attached to the patient's waist and was connected to the stimulator.

  6. An electrical stimulator for sensory substitution.

    Science.gov (United States)

    Pereira, Mauro C; Kassab, Fuad

    2006-01-01

    This work presents an electrical stimulator system for use in sensory substitution (SS), as a mobility aid for visually handicapped people. The whole system passes visual information via cutaneous stimulation, and consists of a webcam, a PC, dedicated hardware to generate stimuli and a 15 x 20 electrode matrix. The same system can also be used in psycophysical and somesthesic research, or even for SS of deaf people, by changing the input signal from a camera to a microphone, and adapting its control software. Circuits for pixel addressing, for signal generation and for switching are described, as well as the software involved in generating a pulse train, which configures the stimuli patterns.

  7. Tissue damage thresholds during therapeutic electrical stimulation

    Science.gov (United States)

    Cogan, Stuart F.; Ludwig, Kip A.; Welle, Cristin G.; Takmakov, Pavel

    2016-04-01

    Objective. Recent initiatives in bioelectronic modulation of the nervous system by the NIH (SPARC), DARPA (ElectRx, SUBNETS) and the GlaxoSmithKline Bioelectronic Medicines effort are ushering in a new era of therapeutic electrical stimulation. These novel therapies are prompting a re-evaluation of established electrical thresholds for stimulation-induced tissue damage. Approach. In this review, we explore what is known and unknown in published literature regarding tissue damage from electrical stimulation. Main results. For macroelectrodes, the potential for tissue damage is often assessed by comparing the intensity of stimulation, characterized by the charge density and charge per phase of a stimulus pulse, with a damage threshold identified through histological evidence from in vivo experiments as described by the Shannon equation. While the Shannon equation has proved useful in assessing the likely occurrence of tissue damage, the analysis is limited by the experimental parameters of the original studies. Tissue damage is influenced by factors not explicitly incorporated into the Shannon equation, including pulse frequency, duty cycle, current density, and electrode size. Microelectrodes in particular do not follow the charge per phase and charge density co-dependence reflected in the Shannon equation. The relevance of these factors to tissue damage is framed in the context of available reports from modeling and in vivo studies. Significance. It is apparent that emerging applications, especially with microelectrodes, will require clinical charge densities that exceed traditional damage thresholds. Experimental data show that stimulation at higher charge densities can be achieved without causing tissue damage, suggesting that safety parameters for microelectrodes might be distinct from those defined for macroelectrodes. However, these increased charge densities may need to be justified by bench, non-clinical or clinical testing to provide evidence of device

  8. Electric Brain Stimulation No Better Than Meds for Depression: Study

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_166920.html Electric Brain Stimulation No Better Than Meds For Depression: ... can't find relief, stimulating the brain with electric impulses may help. But a new study by ...

  9. Electrical stimulation in dysphagia treatment: a justified controversy?

    NARCIS (Netherlands)

    Bogaardt, H. C. A.

    2008-01-01

    Electrical stimulation in dysphagia treatment: a justified controversy? Neuromuscular electrostimulation (LAMES) is a method for stimulating muscles with short electrical pulses. Neuromuscular electrostimulation is frequently used in physiotherapy to strengthen healthy muscles (as in sports

  10. Low voltage electrical stimulation of lamb carcasses: effects on meat quality.

    Science.gov (United States)

    Polidori, P; Lee, S; Kauffman, R G; Marsh, B B

    1999-11-01

    The effects of an early post mortem low voltage electrical stimulation (28 V, 60 Hz) on biochemical changes and on final tenderness in muscles Longissimus thoracis et lumborum and Semimembranosus from lamb carcasses were studied. It was shown that electrical stimulation accelerated the glycolytic process resulting in a significant fall in pH during the first 6 h post mortem in both muscles examined and in a significant reduction in adenosine triphosphate (ATP) content in muscle Longissimus thoracis et lumborum. The effect of electrical stimulation on tenderness was recorded by measuring shear force values 2 and 7 days post mortem. Tenderness was significantly improved by electrical stimulation for the Longissimus thoracis et lumborum both at 2 and at 7 days post mortem, while for Semimembranosus electrical stimulation significantly increased tenderness just at 7 days post mortem.

  11. Functional Electrical Stimulation in Children and Adolescents with Cerebral Palsy

    Science.gov (United States)

    van der Linden, Marietta

    2012-01-01

    In this article, the author talks about functional electrical stimulation in children and adolescents with cerebral palsy. Functional electrical stimulation (FES) is defined as the electrical stimulation of muscles that have impaired motor control, in order to produce a contraction to obtain functionally useful movement. It was first proposed in…

  12. Medical back belt with integrated neuromuscular electrical stimulation

    NARCIS (Netherlands)

    Bottenberg, E. (Eliza); Brinks, G.J. (Ger); Hesse, J. (Jenny)

    2014-01-01

    The medical back belt with integrated neuromuscular electrical stimulation is anorthopedic device, which has two main functions. The first function is to stimulate the backmuscles by using a neuromuscular electrical stimulation device that releases regular,electrical impulses. The second function of

  13. Effect of bleeding method and low voltage electrical stimulation on ...

    African Journals Online (AJOL)

    An early post mortem low voltage electrical stimulation (ES) of the carcasses also had no influence on the cooking loss, drip loss and colour of these muscles. Electrical stimulation did result in a lower pH45 in both the fillet and big drum muscles. However, after 24 h the pH of the muscles did not differ. Electrical stimulation ...

  14. Electrical stimulation superimposed onto voluntary muscular contraction.

    Science.gov (United States)

    Paillard, Thierry; Noé, Frédéric; Passelergue, Philippe; Dupui, Philippe

    2005-01-01

    Electrical stimulation (ES) reverses the order of recruitment of motor units (MU) observed with voluntary muscular contraction (VOL) since under ES, large MU are recruited before small MU. The superimposition of ES onto VOL (superimposed technique: application of an electrical stimulus during a voluntary muscle action) can theoretically activate more motor units than VOL performed alone, which can engender an increase of the contraction force. Two superimposed techniques can be used: (i) the twitch interpolation technique (ITT), which consists of interjecting an electrical stimulus onto the muscle nerve; and (ii) the percutaneous superimposed electrical stimulation technique (PST), where the stimulation is applied to the muscle belly. These two superimposed techniques can be used to evaluate the ability to fully activate a muscle. They can thus be employed to distinguish the central or peripheral nature of fatigue after exhausting exercise. In general, whatever the technique employed, the superimposition of ES onto volitional exercise does not recruit more MU than VOL, except with eccentric actions. Nevertheless, the neuromuscular response associated with the use of the superimposed technique (ITT and PST) depends on the parameter of the superimposed current. The sex and the training level of the subjects can also modify the physiological impact of the superimposed technique. Although the motor control differs drastically between training with ES and VOL, the integration of the superimposed technique in training programmes with healthy subjects does not reveal significant benefits compared with programmes performed only with voluntary exercises. Nevertheless, in a therapeutic context, training programmes using ES superimposition compensate volume and muscle strength deficit with more efficiency than programmes using VOL or ES separately.

  15. Smart control for functional electrical stimulation with optimal pulse intensity

    Directory of Open Access Journals (Sweden)

    Reinert Aljoscha

    2016-09-01

    Full Text Available Transcutaneous electrical stimulation is a common treatment option for patients suffering from spinal cord injury or stroke. Two major difficulties arise when employing electrical stimulation in patients: Accurate stimulation electrode placement and configuration of optimal stimulation parameters. Optimizing the stimulation parameters has the advantage to reduce muscle fatigue after repetitive stimulation. Here we present a newly developed system which is able to automatically find the optimal individual stimulation intensity by varying the pulse length. The effectiveness is measured with flex sensors. By adapting the stimulation parameters, the effect of muscle fatigue can be compensated, allowing for a more stable movement upon stimulation over time.

  16. Anal sphincter responses after perianal electrical stimulation

    DEFF Research Database (Denmark)

    Pedersen, Ejnar; Klemar, B; Schrøder, H D

    1982-01-01

    By perianal electrical stimulation and EMG recording from the external anal sphincter three responses were found with latencies of 2-8, 13-18 and 30-60 ms, respectively. The two first responses were recorded in most cases. They were characterised by constant latency and uniform pattern, were...... stimulation to a minimum of 30-60 ms. This response represented the clinical observable spinal reflex, "the classical anal reflex". The latencies of the two first responses were so short that they probably do not represent spinal reflexes. This was further supported by the effect of epidural anaesthesia which...... left the first responses unaffected but abolished the classical anal reflex. The origin of the two first responses is discussed and models involving antidromal impulse propagation in the efferent fibre as the afferent limbs of the responses are proposed....

  17. Functional electrical stimulation and spinal cord injury.

    Science.gov (United States)

    Ho, Chester H; Triolo, Ronald J; Elias, Anastasia L; Kilgore, Kevin L; DiMarco, Anthony F; Bogie, Kath; Vette, Albert H; Audu, Musa L; Kobetic, Rudi; Chang, Sarah R; Chan, K Ming; Dukelow, Sean; Bourbeau, Dennis J; Brose, Steven W; Gustafson, Kenneth J; Kiss, Zelma H T; Mushahwar, Vivian K

    2014-08-01

    Spinal cord injuries (SCI) can disrupt communications between the brain and the body, resulting in loss of control over otherwise intact neuromuscular systems. Functional electrical stimulation (FES) of the central and peripheral nervous system can use these intact neuromuscular systems to provide therapeutic exercise options to allow functional restoration and to manage medical complications following SCI. The use of FES for the restoration of muscular and organ functions may significantly decrease the morbidity and mortality following SCI. Many FES devices are commercially available and should be considered as part of the lifelong rehabilitation care plan for all eligible persons with SCI. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. A Systematic Review of Electric-Acoustic Stimulation

    Science.gov (United States)

    Ching, Teresa Y. C.; Cowan, Robert

    2013-01-01

    Cochlear implant systems that combine electric and acoustic stimulation in the same ear are now commercially available and the number of patients using these devices is steadily increasing. In particular, electric-acoustic stimulation is an option for patients with severe, high frequency sensorineural hearing impairment. There have been a range of approaches to combining electric stimulation and acoustic hearing in the same ear. To develop a better understanding of fitting practices for devices that combine electric and acoustic stimulation, we conducted a systematic review addressing three clinical questions: what is the range of acoustic hearing in the implanted ear that can be effectively preserved for an electric-acoustic fitting?; what benefits are provided by combining acoustic stimulation with electric stimulation?; and what clinical fitting practices have been developed for devices that combine electric and acoustic stimulation? A search of the literature was conducted and 27 articles that met the strict evaluation criteria adopted for the review were identified for detailed analysis. The range of auditory thresholds in the implanted ear that can be successfully used for an electric-acoustic application is quite broad. The effectiveness of combined electric and acoustic stimulation as compared with electric stimulation alone was consistently demonstrated, highlighting the potential value of preservation and utilization of low frequency hearing in the implanted ear. However, clinical procedures for best fitting of electric-acoustic devices were varied. This clearly identified a need for further investigation of fitting procedures aimed at maximizing outcomes for recipients of electric-acoustic devices. PMID:23539259

  19. Pitch matching psychometrics in electric acoustic stimulation.

    Science.gov (United States)

    Baumann, Uwe; Rader, Tobias; Helbig, Silke; Bahmer, Andreas

    2011-01-01

    Combined electric-acoustic stimulation (EAS) is a therapeutic option for patients with severe to profound mid- and high-frequency hearing loss while low-frequency hearing is mostly unaffected. The present study investigates bimodal pitch matching in EAS users as a function of the angular placement of electrodes. Results are compared with data obtained from previous pitch matching studies. Knowledge of electric and acoustic pitch mapping may be important for effective fitting to control the frequency range of acoustic and electric processing. Pitch adjustment experiments were conducted in eight subjects with residual hearing in the opposite ear as well as in the implanted ear. Four subjects received a standard 31.5-mm electrode array and four subjects received the shorter, more flexible 24-mm FLEX electrode array (PULSARCI100 or SONATATI100 stimulator, MED-EL, Innsbruck, Austria). The subjects' task was to listen to single-electrode stimuli presented at a fixed rate (800 pulses per second) via the cochlear implant and to adjust the frequency of the acoustic stimulus until the perceived pitch matched the perception of the electrically conveyed stimulus. Two to four of the most apical electrodes were tested depending on the range of the individual's residual hearing. Postoperative x rays (modified Stenver's view) were analyzed to compare individual pitch matching data in terms of the electrode arrays' insertion angle. The average mean frequency match for the most apical electrode 1 in EAS subjects implanted with the FLEX array was 583 Hz, while for the two subjects with a deep insertion of the 31.5-mm standard electrode array, the matches were 128 and 223 Hz. Because the residual hearing in the EAS subgroup was rather limited in the high-frequency range, a limited number of basal electrodes were assessed to determine the slope of the electric place/pitch function. A considerable variation in terms of the individual pitch function was observed. The slope of the pitch

  20. The Effect of Electrical Stimulation in Improving Muscle Tone (Clinical)

    Science.gov (United States)

    Azman, M. F.; Azman, A. W.

    2017-11-01

    Electrical stimulation (ES) and also known as neuromuscular electrical stimulation (NMES) and transcutaneous electrical stimulation (TES) involves the use of electrical current to stimulate the nerves or nerve endings that innervate muscle beneath the skin. Electrical stimulation may be applied superficially on the skin (transcutaneously) or directly into a muscle or muscles (intramuscularly) for the primary purpose of enhancing muscle function. The basic theoretical premise is that if the peripheral nerve can be stimulated, the resulting excitation impulse will be transmitted along the nerve to the motor endplates in the muscle, producing a muscle contraction. In this work, the effect of mere electrical stimulation to the muscle bulk and strength are tested. This paper explains how electrical stimulation can affect the muscle bulk, muscle size, muscle tone, muscle atrophy and muscle strength. The experiment and data collection are performed on 5 subjects and the results obtained are analyzed. This research aims to understand the full potential of electrical stimulation and identifying its possible benefits or disadvantages to the muscle properties. The results indicated that electrical stimulation alone able to improve muscle properties but with certain limits and precautions which might be useful in rehabilitation programme.

  1. Effect of electrical stimulation on consumer acceptance of mutton ...

    African Journals Online (AJOL)

    MarianaD

    Animal history influences meat tenderness. LVES – low-voltage electrical stimulation, HVES – high-voltage electrical stimulation, ES – electrically stimulation, .... Overall acceptance. 4.1± 0.65. 4.1 ± 0.64. 0.372. Shear force value. (Newton). 37.7 ± 10.57. 32.6 ± 5.04. 0.168. Total cooking loss (%). 20.2 ± 2.54. 18.1 ± 2.78.

  2. Noninvasive Deep Brain Stimulation via Temporally Interfering Electric Fields

    OpenAIRE

    Grossman, Nir; De Bono, David; Dedic, Nina; Kodandaramaiah, Suhasa B.; Rudenko, Andrii; Suk, Ho-Jun; Cassara, Antonio M.; Neufeld, Esra; Kuster, Niels; Tsai, Li-Huei; Pascual-Leone, Alvaro; Boyden, Edward S.

    2017-01-01

    We report a noninvasive strategy for electrically stimulating neurons at depth. By delivering to the brain multiple electric fields at frequencies too high to recruit neural firing, but which differ by a frequency within the dynamic range of neural firing, we can electrically stimulate neurons throughout a region where interference between the multiple fields results in a prominent electric field envelope modulated at the difference frequency. We validated this temporal interference (TI) conc...

  3. Torque-based optimal acceleration control for electric vehicle

    Science.gov (United States)

    Lu, Dongbin; Ouyang, Minggao

    2014-03-01

    The existing research of the acceleration control mainly focuses on an optimization of the velocity trajectory with respect to a criterion formulation that weights acceleration time and fuel consumption. The minimum-fuel acceleration problem in conventional vehicle has been solved by Pontryagin's maximum principle and dynamic programming algorithm, respectively. The acceleration control with minimum energy consumption for battery electric vehicle(EV) has not been reported. In this paper, the permanent magnet synchronous motor(PMSM) is controlled by the field oriented control(FOC) method and the electric drive system for the EV(including the PMSM, the inverter and the battery) is modeled to favor over a detailed consumption map. The analytical algorithm is proposed to analyze the optimal acceleration control and the optimal torque versus speed curve in the acceleration process is obtained. Considering the acceleration time, a penalty function is introduced to realize a fast vehicle speed tracking. The optimal acceleration control is also addressed with dynamic programming(DP). This method can solve the optimal acceleration problem with precise time constraint, but it consumes a large amount of computation time. The EV used in simulation and experiment is a four-wheel hub motor drive electric vehicle. The simulation and experimental results show that the required battery energy has little difference between the acceleration control solved by analytical algorithm and that solved by DP, and is greatly reduced comparing with the constant pedal opening acceleration. The proposed analytical and DP algorithms can minimize the energy consumption in EV's acceleration process and the analytical algorithm is easy to be implemented in real-time control.

  4. Wireless distributed functional electrical stimulation system

    Directory of Open Access Journals (Sweden)

    Jovičić Nenad S

    2012-08-01

    Full Text Available Abstract Background The control of movement in humans is hierarchical and distributed and uses feedback. An assistive system could be best integrated into the therapy of a human with a central nervous system lesion if the system is controlled in a similar manner. Here, we present a novel wireless architecture and routing protocol for a distributed functional electrical stimulation system that enables control of movement. Methods The new system comprises a set of miniature battery-powered devices with stimulating and sensing functionality mounted on the body of the subject. The devices communicate wirelessly with one coordinator device, which is connected to a host computer. The control algorithm runs on the computer in open- or closed-loop form. A prototype of the system was designed using commercial, off-the-shelf components. The propagation characteristics of electromagnetic waves and the distributed nature of the system were considered during the development of a two-hop routing protocol, which was implemented in the prototype’s software. Results The outcomes of this research include a novel system architecture and routing protocol and a functional prototype based on commercial, off-the-shelf components. A proof-of-concept study was performed on a hemiplegic subject with paresis of the right arm. The subject was tasked with generating a fully functional palmar grasp (closing of the fingers. One node was used to provide this movement, while a second node controlled the activation of extensor muscles to eliminate undesired wrist flexion. The system was tested with the open- and closed-loop control algorithms. Conclusions The system fulfilled technical and application requirements. The novel communication protocol enabled reliable real-time use of the system in both closed- and open-loop forms. The testing on a patient showed that the multi-node system could operate effectively to generate functional movement.

  5. Wireless distributed functional electrical stimulation system.

    Science.gov (United States)

    Jovičić, Nenad S; Saranovac, Lazar V; Popović, Dejan B

    2012-08-09

    The control of movement in humans is hierarchical and distributed and uses feedback. An assistive system could be best integrated into the therapy of a human with a central nervous system lesion if the system is controlled in a similar manner. Here, we present a novel wireless architecture and routing protocol for a distributed functional electrical stimulation system that enables control of movement. The new system comprises a set of miniature battery-powered devices with stimulating and sensing functionality mounted on the body of the subject. The devices communicate wirelessly with one coordinator device, which is connected to a host computer. The control algorithm runs on the computer in open- or closed-loop form. A prototype of the system was designed using commercial, off-the-shelf components. The propagation characteristics of electromagnetic waves and the distributed nature of the system were considered during the development of a two-hop routing protocol, which was implemented in the prototype's software. The outcomes of this research include a novel system architecture and routing protocol and a functional prototype based on commercial, off-the-shelf components. A proof-of-concept study was performed on a hemiplegic subject with paresis of the right arm. The subject was tasked with generating a fully functional palmar grasp (closing of the fingers). One node was used to provide this movement, while a second node controlled the activation of extensor muscles to eliminate undesired wrist flexion. The system was tested with the open- and closed-loop control algorithms. The system fulfilled technical and application requirements. The novel communication protocol enabled reliable real-time use of the system in both closed- and open-loop forms. The testing on a patient showed that the multi-node system could operate effectively to generate functional movement.

  6. Dynamic electrical muscle stimulation (EMS) training of the ...

    African Journals Online (AJOL)

    Previous research on muscle strengthening using electrical stimulation has mainly focused on isometric training. Thus, the aim of the study was to investigate the effect of isokinetic and isotonic electrical muscle stimulation training on the strength of the quadriceps femoris muscle group. A quantitative, experimental ...

  7. Influence of electrical stimulation on carcass and meat quality of ...

    African Journals Online (AJOL)

    In a previous study regarding the effects of Kosher and conventional slaughter techniques on carcass and meat quality of cattle, it was speculated that electrical stimulation may have affected some of the meat qualities. Therefore, the objective of this study was to investigate the effects of electrical stimulation (ES) and ...

  8. Physiological Mechanisms in Combined Electric-Acoustic Stimulation.

    Science.gov (United States)

    Sato, Mika; Baumhoff, Peter; Tillein, Jochen; Kral, Andrej

    2017-09-01

    Electrical stimulation is normally performed on ears that have no hearing function, i.e., lack functional hair cells. The properties of electrically-evoked responses in these cochleae were investigated in several previous studies. Recent clinical developments have introduced cochlear implantation (CI) in residually-hearing ears to improve speech understanding in noise. The present study documents the known physiological differences between electrical stimulation of hair cells and of spiral ganglion cells, respectively, and reviews the mechanisms of combined electric and acoustic stimulation in the hearing ears. Literature review from 1971 to 2016. Compared with pure electrical stimulation the combined electroacoustic stimulation provides additional low-frequency information and expands the dynamic range of the input. Physiological studies document a weaker synchronization of the evoked activity in electrically stimulated hearing ears compared with deaf ears that reduces the hypersynchronization of electrically-evoked activity. The findings suggest the possibility of balancing the information provided by acoustic and electric input using stimulus intensity. Absence of distorting acoustic-electric interactions allows exploiting these clinical benefits of electroacoustic stimulation.

  9. FUNCTIONAL ELECTRICAL STIMULATION FOR CONTROL OF EPILEPTIC SEIZURES

    DEFF Research Database (Denmark)

    Jiao, Jianhang

    stimulation therapies as alternative antiepileptic treatments. In spite of these developments, the antiepileptic efficacy of such electrical stimulation therapies is still relatively low. One reason for not being able to increase this efficacy is the limited knowledge about the effect of the stimulation...

  10. A model of auditory nerve responses to electrical stimulation

    DEFF Research Database (Denmark)

    Joshi, Suyash Narendra; Dau, Torsten; Epp, Bastian

    , fail to correctly predict responses to anodic stimulation. This study presents a model that simulates AN responses to anodic and cathodic stimulation. The main goal was to account for the data obtained with monophasic electrical stimulation in cat AN. The model is based on an exponential integrate...... to neutralize the charge induced during the cathodic phase. Single-neuron recordings in cat auditory nerve using monophasic electrical stimulation show, however, that both phases in isolation can generate an AP. The site of AP generation differs for both phases, being more central for the anodic phase and more...... perception of CI listeners, a model needs to incorporate the correct responsiveness of the AN to anodic and cathodic polarity. Previous models of electrical stimulation have been developed based on AN responses to symmetric biphasic stimulation or to monophasic cathodic stimulation. These models, however...

  11. Electrical stimulation for urinary incontinence in women: a systematic review.

    Science.gov (United States)

    Schreiner, Lucas; Santos, Thais Guimarães dos; Souza, Alessandra Borba Anton de; Nygaard, Christiana Campani; Silva Filho, Irenio Gomes da

    2013-01-01

    Electrical stimulation is commonly recommended to treat urinary incontinence in women. It includes several techniques that can be used to improve stress, urge, and mixed symptoms. However, the magnitude of the alleged benefits is not completely established. To determine the effects of electrical stimulation in women with symptoms or urodynamic diagnoses of stress, urge, and mixed incontinence. Our review included articles published between January 1980 and January 2012. We used the search terms ″urinary incontinence″, ″electrical stimulation ″, ″ intravaginal ″, ″ tibial nerve ″ and ″ neuromodulation ″ for studies including female patients. We evaluated randomized trials that included electrical stimulation in at least one arm of the trial, to treat women with urinary incontinence. Two reviewers independently assessed the data from the trials, for inclusion or exclusion, and methodological analysis. A total of 30 randomized clinical trials were included. Most of the trials involved intravaginal electrical stimulation. Intravaginal electrical stimulation showed effectiveness in treating urge urinary incontinence, but reported contradictory data regarding stress and mixed incontinence. Tibial-nerve stimulation showed promising results in randomized trials with a short follow-up period. Sacral-nerve stimulation yielded interesting results in refractory patients. Tibial-nerve and intravaginal stimulation have shown effectiveness in treating urge urinary incontinence. Sacral-nerve stimulation provided benefits in refractory cases. Presently available data provide no support for the use of intravaginal electrical stimulation to treat stress urinary incontinence in women. Further randomized trials are necessary to determine the magnitude of benefits, with long-term follow-up, and the effectiveness of other electrical-stimulation therapies.

  12. Wireless electrical stimulation: an innovative powerful tool for the treatment of a complicated chronic ulcer.

    Science.gov (United States)

    Castana, Ourania; Dimitrouli, Aekaterini; Argyrakos, Theodoros; Theodorakopoulou, Emilia; Stampolidis, Nektarios; Papadopoulos, Emmanouil; Pallantzas, Athanasios; Stasinopoulos, Ioannis; Poulas, Konstantinos

    2013-03-01

    High-voltage electrical stimulation has been long proposed as a method of accelerating the wound healing process. Its beneficial effect has been successfully evaluated in the treatment of a number of chronic ulcers and burns. We present here the implementation of a new wireless electrical stimulation technique for the treatment of a complicated chronic ulcer of the lower limb. The device is transferring charges to the wound, without any contact with it, creating a microcurrent that is able to generate the current of injury. The results suggest that this easy-to-use method is an effective therapeutic option for chronic ulcers.

  13. Electrical Stimulation for Urinary Incontinence in Women: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Lucas Schreiner

    2013-07-01

    Full Text Available Background Electrical stimulation is commonly recommended to treat urinary incontinence in women. It includes several techniques that can be used to improve stress, urge, and mixed symptoms. However, the magnitude of the alleged benefits is not completely established. Objectives To determine the effects of electrical stimulation in women with symptoms or urodynamic diagnoses of stress, urge, and mixed incontinence. Search Strategy: Our review included articles published between January 1980 and January 2012. We used the search terms “urinary incontinence”, “electrical stimulation”, “intravaginal”, “tibial nerve” and “neuromodulation” for studies including female patients. Selection Criteria We evaluated randomized trials that included electrical stimulation in at least one arm of the trial, to treat women with urinary incontinence. Data Collection and Analysis Two reviewers independently assessed the data from the trials, for inclusion or exclusion, and methodological analysis. Main Results A total of 30 randomized clinical trials were included. Most of the trials involved intravaginal electrical stimulation. Intravaginal electrical stimulation showed effectiveness in treating urge urinary incontinence, but reported contradictory data regarding stress and mixed incontinence. Tibial-nerve stimulation showed promising results in randomized trials with a short follow-up period. Sacral-nerve stimulation yielded interesting results in refractory patients. Conclusions Tibial-nerve and intravaginal stimulation have shown effectiveness in treating urge urinary incontinence. Sacral-nerve stimulation provided benefits in refractory cases. Presently available data provide no support for the use of intravaginal electrical stimulation to treat stress urinary incontinence in women. Further randomized trials are necessary to determine the magnitude of benefits, with long-term follow-up, and the effectiveness of other electrical-stimulation

  14. Transcutaneous electrical nerve stimulation in dysphonic women.

    Science.gov (United States)

    Guirro, Rinaldo Roberto de Jesus; Bigaton, Delaine Rodrigues; Silvério, Kelly Cristina Alves; Berni, Kelly Cristina dos Santos; Distéfano, Giovanna; Santos, Fernanda Lopes dos; Forti, Fabiana

    2008-01-01

    studies indicate correlation between dysphonia and muscle tension. to evaluate bilaterally the electrical activity of the suprahyoid muscles (SH), sternocleidomastoid (SCM), and trapezius (T), the presence of pain and the voice, after applying transcutaneous electrical nerve stimulation (TENS). ten (10) women with nodules or bilateral mucus thickening, and phonation fissure. Volunteers were submitted to 10 TENS sessions (200 micros and 10 Hz) for 30 minutes. Pain was evaluated using an analogical visual scale; the voice was evaluated through laryngoscopy and through a perceptive-auditory and acoustic analysis; and the myoelectric signal was converted using the Root Media Square (RMS). Voice and EMG data gathering was performed during the production of the E/vowel and during spontaneous speech (SS). Shapiro-Wilk Test followed by the Wilcoxon Test, or t Student, or Friedman Test (p readings, pre and pos treatment, for the Right T (RT) (2.80 +/- 1.36 to 1.77 +/- 0.93), the Left T (LT) (3.62 +/- 2.10 to 2.10 +/- 1.06), the Left SCM (LSCM) (2.64 +/- 0.69 to 1.94 +/- 0.95), and the SH (11.59 +/- 7.72 to 7.82 +/- 5.95) during the production of the E/vowel; and for the RT (3.56 +/- 2.77 to 1.93 +/- 1.13), the LT (4.68 +/- 2.56 to 3.09 +/- 2.31), the Right SCM (RSCM) (3.94 +/- 2.04 to 2.51 +/- 1.87), and the LSCM (3.54 +/- 1.04 to 3.12 +/- 3.00) during SS. A relieve in pain was also observed. Regarding the voice analysis, there was a decrease in level of laryngeal injuries; no difference was observed during the production of the E/vowel in the perceptive-auditory analysis; there was a decrease in the level of dysphonia and hoarseness during SS. TENS is effective in improving the clinical and functional signs of dysphonic women.

  15. Toward rational design of electrical stimulation strategies for epilepsy control

    Science.gov (United States)

    Sunderam, Sridhar; Gluckman, Bruce; Reato, Davide; Bikson, Marom

    2009-01-01

    Electrical stimulation is emerging as a viable alternative for epilepsy patients whose seizures are not alleviated by drugs or surgery. Its attractions are temporal and spatial specificity of action, flexibility of waveform parameters and timing, and the perception that its effects are reversible unlike resective surgery. However, despite significant advances in our understanding of mechanisms of neural electrical stimulation, clinical electrotherapy for seizures relies heavily on empirical tuning of parameters and protocols. We highlight concurrent treatment goals with potentially conflicting design constraints that must be resolved when formulating rational strategies for epilepsy electrotherapy: namely seizure reduction versus cognitive impairment, stimulation efficacy versus tissue safety, and mechanistic insight versus clinical pragmatism. First, treatment markers, objectives, and metrics relevant to electrical stimulation for epilepsy are discussed from a clinical perspective. Then the experimental perspective is presented, with the biophysical mechanisms and modalities of open-loop electrical stimulation, and the potential benefits of closed-loop control for epilepsy. PMID:19926525

  16. Electrical carotid sinus stimulation in treatment resistant arterial hypertension.

    Science.gov (United States)

    Jordan, Jens; Heusser, Karsten; Brinkmann, Julia; Tank, Jens

    2012-12-24

    Treatment resistant arterial hypertension is commonly defined as blood pressure that remains above goal in spite of the concurrent use of three antihypertensive agents of different classes. The sympathetic nervous system promotes arterial hypertension and cardiovascular as well as renal damage, thus, providing a logical treatment target in these patients. Recent physiological studies suggest that baroreflex mechanisms contribute to long-term control of sympathetic activity and blood pressure providing an impetus for the development of electrical carotid sinus stimulators. The concept behind electrical stimulation of baroreceptors or baroreflex afferent nerves is that the stimulus is sensed by the brain as blood pressure increase. Then, baroreflex efferent structures are adjusted to counteract the perceived blood pressure increase. Electrical stimulators directly activating afferent baroreflex nerves were developed years earlier but failed for technical reasons. Recently, a novel implantable device was developed that produces an electrical field stimulation of the carotid sinus wall. Carefully conducted experiments in dogs provided important insight in mechanisms mediating the depressor response to electrical carotid sinus stimulation. Moreover, these studies showed that the treatment success may depend on the underlying pathophysiology of the hypertension. Clinical studies suggest that electrical carotid sinus stimulation attenuates sympathetic activation of vasculature, heart, and kidney while augmenting cardiac vagal regulation, thus lowering blood pressure. Yet, not all patients respond to treatment. Additional clinical trials are required. Patients equipped with an electrical carotid sinus stimulator provide a unique opportunity gaining insight in human baroreflex physiology. Copyright © 2012. Published by Elsevier B.V.

  17. Noninvasive Deep Brain Stimulation via Temporally Interfering Electric Fields.

    Science.gov (United States)

    Grossman, Nir; Bono, David; Dedic, Nina; Kodandaramaiah, Suhasa B; Rudenko, Andrii; Suk, Ho-Jun; Cassara, Antonino M; Neufeld, Esra; Kuster, Niels; Tsai, Li-Huei; Pascual-Leone, Alvaro; Boyden, Edward S

    2017-06-01

    We report a noninvasive strategy for electrically stimulating neurons at depth. By delivering to the brain multiple electric fields at frequencies too high to recruit neural firing, but which differ by a frequency within the dynamic range of neural firing, we can electrically stimulate neurons throughout a region where interference between the multiple fields results in a prominent electric field envelope modulated at the difference frequency. We validated this temporal interference (TI) concept via modeling and physics experiments, and verified that neurons in the living mouse brain could follow the electric field envelope. We demonstrate the utility of TI stimulation by stimulating neurons in the hippocampus of living mice without recruiting neurons of the overlying cortex. Finally, we show that by altering the currents delivered to a set of immobile electrodes, we can steerably evoke different motor patterns in living mice. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Electrical Stimulation for Pressure Injuries: A Health Technology Assessment

    Science.gov (United States)

    Lambrinos, Anna; Falk, Lindsey; Ali, Arshia; Holubowich, Corinne; Walter, Melissa

    2017-01-01

    Background Pressure injuries (bedsores) are common and reduce quality of life. They are also costly and difficult to treat. This health technology assessment evaluates the effectiveness, cost-effectiveness, budget impact, and lived experience of adding electrical stimulation to standard wound care for pressure injuries. Methods We conducted a systematic search for studies published to December 7, 2016, limited to randomized and non–randomized controlled trials examining the effectiveness of electrical stimulation plus standard wound care versus standard wound care alone for patients with pressure injuries. We assessed the quality of evidence through Grading of Recommendations Assessment, Development, and Evaluation (GRADE). In addition, we conducted an economic literature review and a budget impact analysis to assess the cost-effectiveness and affordability of electrical stimulation for treatment of pressure ulcers in Ontario. Given uncertainties in clinical evidence and resource use, we did not conduct a primary economic evaluation. Finally, we conducted qualitative interviews with patients and caregivers about their experiences with pressure injuries, currently available treatments, and (if applicable) electrical stimulation. Results Nine randomized controlled trials and two non–randomized controlled trials were found from the systematic search. There was no significant difference in complete pressure injury healing between adjunct electrical stimulation and standard wound care. There was a significant difference in wound surface area reduction favouring electrical stimulation compared with standard wound care. The only study on cost-effectiveness of electrical stimulation was partially applicable to the patient population of interest. Therefore, the cost-effectiveness of electrical stimulation cannot be determined. We estimate that the cost of publicly funding electrical stimulation for pressure injuries would be $0.77 to $3.85 million yearly for the next 5

  19. Electrical Stimulation of the Heart: Pacing, Arrhythmias, and Defibrillation

    Science.gov (United States)

    Roth, Bradley J.

    2000-03-01

    Electrical stimulation of the heart underlies cardiac pacing and defibrillation. The "bidomain model" describes the anisotropic electrical properties of cardiac tissue. In particular, this model predicts mechanisms by which applied electric fields change the transmembrane potential of the myocardial cells. During unipolar stimulation, the bidomain model can explain "make" and "break" stimulation. Furthermore, it elucidates the cause of the "dip" in the anodal strength-interval curve, and predicts the initiation of novel quatrefoil reentry patterns. These results are beginning to shed light on the mechanisms of arrhythmia induction and defibrillation.

  20. Design of electrical stimulation bioreactors for cardiac tissue engineering.

    Science.gov (United States)

    Tandon, N; Marsano, A; Cannizzaro, C; Voldman, J; Vunjak-Novakovic, G

    2008-01-01

    Electrical stimulation has been shown to improve functional assembly of cardiomyocytes in vitro for cardiac tissue engineering. Carbon electrodes were found in past studies to have the best current injection characteristics. The goal of this study was to develop rational experimental design principles for the electrodes and stimulation regime, in particular electrode configuration, electrode ageing, and stimulation amplitude. Carbon rod electrodes were compared via electrochemical impedance spectroscopy (EIS) and we identified a safety range of 0 to 8 V/cm by comparing excitation thresholds and maximum capture rates for neonatal rat cardiomyocytes cultured with electrical stimulation. We conclude with recommendations for studies involving carbon electrodes for cardiac tissue engineering.

  1. Particle acceleration by stimulated emission of radiation in cylindrical waveguide

    Science.gov (United States)

    Tian, Xiu-Fang; Wu, Cong-Feng; Jia, Qi-Ka

    2015-07-01

    In particle acceleration by stimulated emission of radiation (PASER), efficient interaction occurs when a train of micro-bunches has periodicity identical to the resonance frequency of the medium. Previous theoretical calculations based on the simplified model have only considered the energy exchange in the boundless condition. Under experimental conditions, however, the gas active medium must be guided by the metal waveguide. In this paper, we have developed a model of the energy exchange between a train of micro-bunches and a gas mixture active medium in a waveguide boundary for the first time, based on the theory of electromagnetic fields, and made detailed analysis and calculations with MathCAD. The results show that energy density can be optimized to a certain value to get the maximum energy exchange. Supported by National Natural Science Foundation of China (10675116) and Major State Basic Research Development Programme of China (2011CB808301)

  2. Effect of abdominal vibroacoustic stimulation on sound and acceleration levels at the head of the fetal sheep.

    Science.gov (United States)

    Abrams, R M; Peters, A J; Gerhardt, K J

    1997-08-01

    To measure the vibratory response of the fetal head and abdominal wall in sheep during vibroacoustic stimulation. A piezoresistive accelerometer was attached to the skulls of seven sheep fetuses (128-134 days' gestational age), and a miniature hydrophone was attached to the skin overlying the fetal temporal bone. During fetal preparation and vibroacoustic stimulation procedures, ewes were anesthetized and supine. Vibroacoustic stimulation of the maternal abdomen was produced by each of two clinical devices that differed in spectral content, and an electric toothbrush. The approximate fundamental frequencies (f0) and first overtones (f1), as determined by both recordings of intrauterine sound pressure level and fetal head acceleration, were as follows: fetal acoustic stimulator, 75 and 150 Hz; electronic larynx, 150 and 300 Hz; and electric toothbrush, 25 and 50 Hz, respectively. At fundamental frequencies and first overtones, the ranges of fetal head accelerations (expressed in 1/12-octave bands) were as follows: fetal acoustic stimulator, 10-53 and 25-224 mm/sec2; electronic larynx, 10-53 and 18-114 mm/sec2; and electric toothbrush, 33-792 and 8-116 mm/sec2, respectively. Sound pressure levels exceeded 110 dB in all cases. High sound pressure levels in the uterus were proportional to fetal head vibration levels. Vibroacoustic stimulation of the surface of the abdomen of pregnant sheep is accompanied by both acoustic and vibratory exposure of the fetus.

  3. Optimization of Electrical Stimulation Parameters for Cardiac Tissue Engineering

    Science.gov (United States)

    Tandon, Nina; Marsano, Anna; Maidhof, Robert; Wan, Leo; Park, Hyoungshin; Vunjak-Novakovic, Gordana

    2010-01-01

    In vitro application of pulsatile electrical stimulation to neonatal rat cardiomyocytes cultured on polymer scaffolds has been shown to improve the functional assembly of cells into contractile cardiac tissue constrcuts. However, to date, the conditions of electrical stimulation have not been optimized. We have systematically varied the electrode material, amplitude and frequency of stimulation, to determine the conditions that are optimal for cardiac tissue engineering. Carbon electrodes, exhibiting the highest charge-injection capacity and producing cardiac tissues with the best structural and contractile properties, and were thus used in tissue engineering studies. Cardiac tissues stimulated at 3V/cm amplitude and 3Hz frequency had the highest tissue density, the highest concentrations of cardiac troponin-I and connexin-43, and the best developed contractile behavior. These findings contribute to defining bioreactor design specifications and electrical stimulation regime for cardiac tissue engineering. PMID:21604379

  4. Differential stimulation of the retina with subretinally injected exogenous neurotransmitter: A biomimetic alternative to electrical stimulation

    Science.gov (United States)

    Rountree, Corey M.; Inayat, Samsoon; Troy, John B.; Saggere, Laxman

    2016-12-01

    Subretinal stimulation of the retina with neurotransmitters, the normal means of conveying visual information, is a potentially better alternative to electrical stimulation widely used in current retinal prostheses for treating blindness from photoreceptor degenerative diseases. Yet, no subretinal electrical or chemical stimulation study has stimulated the OFF and ON pathways differentially through inner retinal activation. Here, we demonstrate the feasibility of differentially stimulating retinal ganglion cells (RGCs) through the inner nuclear layer of the retina with glutamate, a primary neurotransmitter chemical, in a biomimetic way. We show that controlled pulsatile delivery of glutamate into the subsurface of explanted wild-type rat retinas elicits highly localized simultaneous inhibitory and excitatory spike rate responses in OFF and ON RGCs. We also present the spatiotemporal characteristics of RGC responses to subretinally injected glutamate and the therapeutic stimulation parameters. Our findings could pave the way for future development of a neurotransmitter-based subretinal prosthesis offering more naturalistic vision and better visual acuity than electrical prostheses.

  5. Non-invasive neuromuscular electrical stimulation in patients with central nervous system lesions: an educational review

    National Research Council Canada - National Science Library

    Schuhfried, Othmar; Crevenna, Richard; Fialka-Moser, Veronika; Paternostro-Sluga, Tatjana

    2012-01-01

    ...) functional electrical stimulation. Therapeutic electrical stimulation improves neuromuscular functional condition by strengthening muscles, increasing motor control, reducing spasticity, decreasing pain and increasing range of motion...

  6. Effect of electrical stimulation of carcasses from Dorper sheep with ...

    African Journals Online (AJOL)

    Samples of the left M. longissimus thoracis et lumborum of both groups were oven roasted and a consumer panel evaluated the acceptability of the mutton regarding ... Moreover, the variation in shear force values of meat samples from the electrically stimulated group was less compared to that of the non-stimulated group, ...

  7. Electrical muscle stimulation (EMS) training of the hamstrings ...

    African Journals Online (AJOL)

    The aim of this study was to investigate the effects of electrical muscle stimulation (EMS) training on hamstring muscle strength. The study utilised a quantitative experimental research design. The intervention was assessed using a Humac Norm 7000 Dynamometer. A Chattanooga Intelect Mobile Combo muscle stimulator ...

  8. Design of Electrical Stimulation Bioreactors for Cardiac Tissue Engineering

    OpenAIRE

    Tandon, N.; Marsano, A.; Cannizzaro, C.; Voldman, J.; Vunjak-Novakovic, G.

    2008-01-01

    Electrical stimulation has been shown to improve functional assembly of cardiomyocytes in vitro for cardiac tissue engineering. Carbon electrodes were found in past studies to have the best current injection characteristics. The goal of this study was to develop rational experimental design principles for the electrodes and stimulation regime, in particular electrode configuration, electrode ageing, and stimulation amplitude. Carbon rod electrodes were compared via electrochemical impedance s...

  9. Ocular torsion responses to sinusoidal electrical vestibular stimulation.

    Science.gov (United States)

    Mackenzie, Stuart W; Reynolds, Raymond F

    2017-11-21

    Eye movements evoked by electrical vestibular stimulation (EVS) offer potential for diagnosing vestibular dysfunction. However, ocular recording techniques are often too invasive or impractical for routine clinical use. Furthermore, the kinematic nature of the EVS signal is not fully understood in terms of movement sensations. We apply sinusoidal EVS stimuli varying from 0.05 to 20Hz, and record the eye in darkness using an infrared camera. Eye movement was measured offline using commercially available software to track iris striations. Response gain and phase were calculated separately for eye position, velocity and acceleration across all frequencies, to determine how the brain interprets the EVS signal. Ocular torsion responses were observed at the same frequency as the stimulus, for all frequencies, while lateral/vertical responses were minimal or absent. Response gain and phase resembled previously reported responses to natural rotation, but only when analysing eye velocity, not position or acceleration. Our method offers a simple, affordable, reliable and non-invasive method for tracking the ocular response to EVS. It is more convenient than scleral coil recordings, or marking the sclera to aid video tracking. It also allows us to assess the torsional VOR at frequencies not possible with natural stimuli. Ocular torsion responses to EVS can be readily assessed using sinusoidal stimuli combined with an infrared camera. Gain and phase analysis suggests that the central nervous system interprets the stimulus as head roll velocity. Future work will assess the diagnostic potential for patients with vestibular disorders. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

  10. Electrical Engineering in Los Alamos Neutron Science Center Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Michael James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-11-30

    The field of electrical engineering plays a significant role in particle accelerator design and operations. Los Alamos National Laboratories LANSCE facility utilizes the electrical energy concepts of power distribution, plasma generation, radio frequency energy, electrostatic acceleration, signals and diagnostics. The culmination of these fields produces a machine of incredible potential with uses such as isotope production, neutron spallation, neutron imaging and particle analysis. The key isotope produced in LANSCE isotope production facility is Strontium-82 which is utilized for medical uses such as cancer treatment and positron emission tomography also known as PET scans. Neutron spallation is one of the very few methods used to produce neutrons for scientific research the other methods are natural decay of transuranic elements from nuclear reactors. Accelerator produce neutrons by accelerating charged particles into neutron dense elements such as tungsten imparting a neutral particle with kinetic energy, this has the benefit of producing a large number of neutrons as well as minimizing the waste generated. Utilizing the accelerator scientist can gain an understanding of how various particles behave and interact with matter to better understand the natural laws of physics and the universe around us.

  11. [Impact of the Overlap Region Between Acoustic and Electric Stimulation].

    Science.gov (United States)

    Baumann, Uwe; Mocka, Moritz

    2017-06-01

    Patients with residual hearing in the low frequencies and ski-slope hearing loss with partial deafness at medium and high frequencies receive a cochlear implant treatment with electric-acoustic stimulation (EAS, "hybrid" stimulation). In the border region between electric and acoustic stimulation a superposition of the 2 types of stimulation is expected. The area of overlap is determined by the insertion depth of the stimulating electrode and the lower starting point of signal transmission provided by the CI speech processor. The study examined the influence of the variation of the electric-acoustic overlap area on speech perception in noise, whereby the width of the "transmission gap" between the 2 different stimulus modalities was varied by 2 different methods. The results derived from 9 experienced users of the MED-EL Duet 2 speech processor show that the electric-acoustic overlapping area and with it the crossover frequency between the acoustic part and the CI should be adjusted individually. Overall, speech reception thresholds (SRT) showed a wide variation of results in between subjects. Further studies shall investigate whether generalized procedures about the setting of the overlap between electric and acoustic stimulation are reasonable, whereby an increased number of subjects and a longer period of acclimatization prior to the conduction of hearing tests deemed necessary. © Georg Thieme Verlag KG Stuttgart · New York.

  12. Therapeutic electrical stimulation for spasticity: quantitative gait analysis.

    Science.gov (United States)

    Pease, W S

    1998-01-01

    Improvement in motor function following electrical stimulation is related to strengthening of the stimulated spastic muscle and inhibition of the antagonist. A 26-year-old man with familial spastic paraparesis presented with gait dysfunction and bilateral lower limb spastic muscle tone. Clinically, muscle strength and sensation were normal. He was considered appropriate for a trial of therapeutic electrical stimulation following failed trials of physical therapy and baclofen. No other treatment was used concurrent with the electrical stimulation. Before treatment, quantitative gait analysis revealed 63% of normal velocity and a crouched gait pattern, associated with excessive electromyographic activity in the hamstrings and gastrocnemius muscles. Based on these findings, bilateral stimulation of the quadriceps and anterior compartment musculature was performed two to three times per week for three months. Repeat gait analysis was conducted three weeks after the cessation of stimulation treatment. A 27% increase in velocity was noted associated with an increase in both cadence and right step length. Right hip and bilateral knee stance motion returned to normal (rather than "crouched"). No change in the timing of dynamic electromyographic activity was seen. These findings suggest a role for the use of electrical stimulation for rehabilitation of spasticity. The specific mechanism of this improvement remains uncertain.

  13. Electrical stimulation promotes regeneration of injured oculomotor nerves in dogs

    Directory of Open Access Journals (Sweden)

    Lei Du

    2016-01-01

    Full Text Available Functional recovery after oculomotor nerve injury is very poor. Electrical stimulation has been shown to promote regeneration of injured nerves. We hypothesized that electrical stimulation would improve the functional recovery of injured oculomotor nerves. Oculomotor nerve injury models were created by crushing the right oculomotor nerves of adult dogs. Stimulating electrodes were positioned in both proximal and distal locations of the lesion, and non-continuous rectangular, biphasic current pulses (0.7 V, 5 Hz were administered 1 hour daily for 2 consecutive weeks. Analysis of the results showed that electrophysiological and morphological recovery of the injured oculomotor nerve was enhanced, indicating that electrical stimulation improved neural regeneration. Thus, this therapy has the potential to promote the recovery of oculomotor nerve dysfunction.

  14. Approximating transcranial magnetic stimulation with electric stimulation in mouse: a simulation study.

    Science.gov (United States)

    Barnes, Walter L; Lee, Won Hee; Peterchev, Angel V

    2014-01-01

    Rodent models are valuable for preclinical examination of novel therapeutic techniques, including transcranial magnetic stimulation (TMS). However, comparison of TMS effects in rodents and humans is confounded by inaccurate scaling of the spatial extent of the induced electric field in rodents. The electric field is substantially less focal in rodent models of TMS due to the technical restrictions of making very small coils that can handle the currents required for TMS. We examine the electric field distributions generated by various electrode configurations of electric stimulation in an inhomogeneous high-resolution finite element mouse model, and show that the electric field distributions produced by human TMS can be approximated by electric stimulation in mouse. Based on these results and the limits of magnetic stimulation in mice, we argue that the most practical and accurate way to model focal TMS in mice is electric stimulation through either cortical surface electrodes or electrodes implanted halfway through the mouse cranium. This approach could allow much more accurate approximation of the human TMS electric field focality and strength than that offered by TMS in mouse, enabling, for example, focal targeting of specific cortical regions, which is common in human TMS paradigms.

  15. Electrical stimulation of the upper extremity in stroke: cyclic versus EMG-triggered stimulation

    NARCIS (Netherlands)

    de Kroon, Joke R.; IJzerman, Maarten Joost

    2008-01-01

    Objective: To compare the effect of cyclic and electromyography (EMG)-triggered electrical stimulation on motor impairment and function of the affected upper extremity in chronic stroke. Design: Randomized controlled trial. Setting: Outpatient clinic of a rehabilitation centre. Subjects and

  16. Comparative Evaluation of Tactile Sensation by Electrical and Mechanical Stimulation.

    Science.gov (United States)

    Yem, Vibol; Kajimoto, Hiroyuki

    2017-01-01

    An electrotactile display is a tactile interface that provides tactile perception by passing electrical current through the surface of the skin. It is actively used instead of mechanical tactile displays for tactile feedback because of several advantages such as its small and thin size, light weight, and high responsiveness. However, the similarities and differences between these sensations is still not clear. This study directly compares the intensity sensation of electrotactile stimulation to that of mechanical stimulation, and investigates the characteristic sensation of anodic and cathodic stimulation. In the experiment, participants underwent a 30 pps electrotactile stimulus every one second to their middle finger, and were asked to match this intensity by adjusting the intensity of a mechanical tactile stimulus to an index finger. The results showed that anodic stimulation mainly produced vibration sensation, whereas cathodic sensation produced both vibration and pressure sensations. Relatively low pressure sensation was also observed for anodic stimulation but it remains low, regardless of the increasing of electrical intensity.

  17. Electric-field-stimulated protein mechanics.

    Science.gov (United States)

    Hekstra, Doeke R; White, K Ian; Socolich, Michael A; Henning, Robert W; Šrajer, Vukica; Ranganathan, Rama

    2016-12-15

    The internal mechanics of proteins-the coordinated motions of amino acids and the pattern of forces constraining these motions-connects protein structure to function. Here we describe a new method combining the application of strong electric field pulses to protein crystals with time-resolved X-ray crystallography to observe conformational changes in spatial and temporal detail. Using a human PDZ domain (LNX2PDZ2) as a model system, we show that protein crystals tolerate electric field pulses strong enough to drive concerted motions on the sub-microsecond timescale. The induced motions are subtle, involve diverse physical mechanisms, and occur throughout the protein structure. The global pattern of electric-field-induced motions is consistent with both local and allosteric conformational changes naturally induced by ligand binding, including at conserved functional sites in the PDZ domain family. This work lays the foundation for comprehensive experimental study of the mechanical basis of protein function.

  18. Efficacy of Electrical Pudendal Nerve Stimulation versus Transvaginal Electrical Stimulation in Treating Female Idiopathic Urgency Urinary Incontinence.

    Science.gov (United States)

    Wang, Siyou; Lv, Jianwei; Feng, Xiaoming; Lv, Tingting

    2017-06-01

    We compared the efficacy of electrical pudendal nerve stimulation vs transvaginal electrical stimulation to treat female idiopathic urgency urinary incontinence. A total of 120 female patients with idiopathic urgency urinary incontinence refractory to medication were randomized at a ratio of 2:1 to group 1 of 80 patients and group 2 of 40. Groups 1 and 2 were treated with electrical pudendal nerve stimulation and transvaginal electrical stimulation, respectively. To perform electrical pudendal nerve stimulation long acupuncture needles were deeply inserted into 4 sacrococcygeal points and electrified to stimulate pudendal nerves. Outcome measures were the 24-hour pad test and a questionnaire to measure the severity of symptoms and quality of life in women with urgency urinary incontinence. The median severity of symptoms and quality of life score on the urgency urinary incontinence questionnaire (urgency urinary incontinence total score) was 13 (range 7 to 18.75) in group 1 and 11 (range 8 to 16) in group 2 before treatment, which decreased to 2 (range 0 to 6.75) in group 1 and 6.5 (range 3.25 to 10.75) in group 2 (both p incontinence total score was lower and the therapeutic effect was better in group 1 than in group 2 (both p incontinence. Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  19. Accelerated Aging with Electrical Overstress and Prognostics for Power MOSFETs

    Science.gov (United States)

    Saha, Sankalita; Celaya, Jose Ramon; Vashchenko, Vladislav; Mahiuddin, Shompa; Goebel, Kai F.

    2011-01-01

    Power electronics play an increasingly important role in energy applications as part of their power converter circuits. Understanding the behavior of these devices, especially their failure modes as they age with nominal usage or sudden fault development is critical in ensuring efficiency. In this paper, a prognostics based health management of power MOSFETs undergoing accelerated aging through electrical overstress at the gate area is presented. Details of the accelerated aging methodology, modeling of the degradation process of the device and prognostics algorithm for prediction of the future state of health of the device are presented. Experiments with multiple devices demonstrate the performance of the model and the prognostics algorithm as well as the scope of application. Index Terms Power MOSFET, accelerated aging, prognostics

  20. Fully regenerative braking and improved acceleration for electrical vehicles

    OpenAIRE

    Melis, Wim J.C.; Chishty, Owais

    2013-01-01

    Generally, car brake systems use hydraulic brake technology, which converts the excess of kinetic energy into heat, effectively resulting in an energy loss. Regenerative braking technology focuses on converting this kinetic energy of the decelerating vehicle back into electrical energy that can then be reused for example during acceleration. Current hybrid vehicles are equipped with such regenerative braking technology, which makes them particularly interesting for situations with frequent de...

  1. Stimulating the Comfort of Textile Electrodes in Wearable Neuromuscular Electrical Stimulation

    Directory of Open Access Journals (Sweden)

    Hui Zhou

    2015-07-01

    Full Text Available Textile electrodes are becoming an attractive means in the facilitation of surface electrical stimulation. However, the stimulation comfort of textile electrodes and the mechanism behind stimulation discomfort is still unknown. In this study, a textile stimulation electrode was developed using conductive fabrics and then its impedance spectroscopy, stimulation thresholds, and stimulation comfort were quantitatively assessed and compared with those of a wet textile electrode and a hydrogel electrode on healthy subjects. The equivalent circuit models and the finite element models of different types of electrode were built based on the measured impedance data of the electrodes to reveal the possible mechanism of electrical stimulation pain. Our results showed that the wet textile electrode could achieve similar stimulation performance as the hydrogel electrode in motor threshold and stimulation comfort. However, the dry textile electrode was found to have very low pain threshold and induced obvious cutaneous painful sensations during stimulation, in comparison to the wet and hydrogel electrodes. Indeed, the finite element modeling results showed that the activation function along the z direction at the depth of dermis epidermis junction of the dry textile electrode was significantly larger than that of the wet and hydrogel electrodes, thus resulting in stronger activation of pain sensing fibers. Future work will be done to make textile electrodes have similar stimulation performance and comfort as hydrogel electrodes.

  2. Stimulating the Comfort of Textile Electrodes in Wearable Neuromuscular Electrical Stimulation.

    Science.gov (United States)

    Zhou, Hui; Lu, Yi; Chen, Wanzhen; Wu, Zhen; Zou, Haiqing; Krundel, Ludovic; Li, Guanglin

    2015-07-16

    Textile electrodes are becoming an attractive means in the facilitation of surface electrical stimulation. However, the stimulation comfort of textile electrodes and the mechanism behind stimulation discomfort is still unknown. In this study, a textile stimulation electrode was developed using conductive fabrics and then its impedance spectroscopy, stimulation thresholds, and stimulation comfort were quantitatively assessed and compared with those of a wet textile electrode and a hydrogel electrode on healthy subjects. The equivalent circuit models and the finite element models of different types of electrode were built based on the measured impedance data of the electrodes to reveal the possible mechanism of electrical stimulation pain. Our results showed that the wet textile electrode could achieve similar stimulation performance as the hydrogel electrode in motor threshold and stimulation comfort. However, the dry textile electrode was found to have very low pain threshold and induced obvious cutaneous painful sensations during stimulation, in comparison to the wet and hydrogel electrodes. Indeed, the finite element modeling results showed that the activation function along the z direction at the depth of dermis epidermis junction of the dry textile electrode was significantly larger than that of the wet and hydrogel electrodes, thus resulting in stronger activation of pain sensing fibers. Future work will be done to make textile electrodes have similar stimulation performance and comfort as hydrogel electrodes.

  3. Gastric Electrical Stimulation with the Enterra System: A Systematic Review.

    Science.gov (United States)

    Lal, Nikhil; Livemore, Sam; Dunne, Declan; Khan, Iftikhar

    2015-01-01

    Background. Gastric electrical stimulation (GES) is a surgically implanted treatment option for refractory gastroparesis. Aim. To systematically appraise the current evidence for the use of gastric electrical stimulation and suggest a method of standardisation of assessment and follow-up in these patients. Methods. A systematic review of PubMed, Web of Science, DISCOVER, and Cochrane Library was conducted using the keywords including gastric electrical stimulation, gastroparesis, nausea, and vomiting and neuromodulation, stomach, central nervous system, gastric pacing, electrical stimulation, and gastrointestinal. Results. 1139 potentially relevant articles were identified, of which 21 met the inclusion criteria and were included. The quality of studies was variable. There was a variation in outcome measures and follow-up methodology. Included studies suggested significant reductions in symptom severity reporting over the study period, but improvements in gastric emptying time were variable and rarely correlated with symptom improvement. Conclusion. The evidence in support of gastric electrical stimulation is limited and heterogeneous in quality. While current evidence has shown a degree of efficacy in these patients, high-quality, large clinical trials are needed to establish the efficacy of this therapy and to identify the patients for whom this therapy is inappropriate. A consensus view on essential preoperative assessment and postoperative measurement is needed.

  4. Gastric Electrical Stimulation with the Enterra System: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Nikhil Lal

    2015-01-01

    Full Text Available Background. Gastric electrical stimulation (GES is a surgically implanted treatment option for refractory gastroparesis. Aim. To systematically appraise the current evidence for the use of gastric electrical stimulation and suggest a method of standardisation of assessment and follow-up in these patients. Methods. A systematic review of PubMed, Web of Science, DISCOVER, and Cochrane Library was conducted using the keywords including gastric electrical stimulation, gastroparesis, nausea, and vomiting and neuromodulation, stomach, central nervous system, gastric pacing, electrical stimulation, and gastrointestinal. Results. 1139 potentially relevant articles were identified, of which 21 met the inclusion criteria and were included. The quality of studies was variable. There was a variation in outcome measures and follow-up methodology. Included studies suggested significant reductions in symptom severity reporting over the study period, but improvements in gastric emptying time were variable and rarely correlated with symptom improvement. Conclusion. The evidence in support of gastric electrical stimulation is limited and heterogeneous in quality. While current evidence has shown a degree of efficacy in these patients, high-quality, large clinical trials are needed to establish the efficacy of this therapy and to identify the patients for whom this therapy is inappropriate. A consensus view on essential preoperative assessment and postoperative measurement is needed.

  5. Intracavitary electrical stimulation as treatment for overactive bladder: systematic review

    Directory of Open Access Journals (Sweden)

    Rafaela Fintelman Rodrigues

    Full Text Available Abstract Introduction: Overactive bladder (OAB is a clinical diagnosis of irritating urinary symptoms that influence on sufferers' life quality. There are effective treatments described in literature, but most of them present adverse effects. One way of treatment is the use of electrical stimulation, which has been widely used, but studies show varying results. Objective: To verify if intracavitary electrical stimulation can be effective in patients with OAB. Methods: online databases were searched with specific descriptors to find randomized clinical trials on overactive bladder treated with intracavitary electrical stimulation. Only articles with score equal or higher than 5 in methodological PEDro scale were used and those that described intra and / or inter-group P-value. Results: 217 articles were found, but only 6 were analyzed by the selection criteria. The studies show that electrical stimulation promotes the reduction of urinary frequency, urinary incontinence, nocturia, urgency and the number of protectors used, and improvements in maximum cystometric bladder capacity, symptoms of OAB and quality of life. Conclusion: Electrical stimulation was effective in patients with OAB and can be used before any invasive treatment due to none side effects.

  6. Non-invasive neuromuscular electrical stimulation in patients with central nervous system lesions: an educational review.

    Science.gov (United States)

    Schuhfried, Othmar; Crevenna, Richard; Fialka-Moser, Veronika; Paternostro-Sluga, Tatjana

    2012-02-01

    The aim of this educational review is to provide an overview of the clinical application of transcutaneous electrical stimulation of the extremities in patients with upper motor neurone lesions. In general two methods of electrical stimulation can be distinguished: (i) therapeutic electrical stimulation, and (ii) functional electrical stimulation. Therapeutic electrical stimulation improves neuromuscular functional condition by strengthening muscles, increasing motor control, reducing spasticity, decreasing pain and increasing range of motion. Transcutaneous electrical stimulation may be used for neuromuscular electrical stimulation inducing repetitive muscle contraction, electromyography-triggered neuromuscular electrical stimulation, position-triggered electrical stimulation and subsensory or sensory transcutaneous electric stimulation. Functional electrical stimulation provokes muscle contraction and thereby produces a functionally useful movement during stimulation. In patients with spinal cord injuries or stroke, electrical upper limb neuroprostheses are applied to enhance upper limb and hand function, and electrical lower limb neuroprostheses are applied for restoration of standing and walking. For example, a dropped foot stimulator is used to trigger ankle dorsiflexion to restore gait function. A review of the literature and clinical experience of the use of therapeutic electrical stimulation as well as of functional electrical stimulation in combination with botulinum toxin, exercise therapy and/or splinting are presented. Although the evidence is limited we conclude that neuromuscular electrical stimulation in patients with central nervous system lesions can be an effective modality to improve function, and that combination with other treatments has an additive therapeutic effect.

  7. Higher-order power harmonics of pulsed electrical stimulation modulates corticospinal contribution of peripheral nerve stimulation.

    Science.gov (United States)

    Chen, Chiun-Fan; Bikson, Marom; Chou, Li-Wei; Shan, Chunlei; Khadka, Niranjan; Chen, Wen-Shiang; Fregni, Felipe

    2017-03-03

    It is well established that electrical-stimulation frequency is crucial to determining the scale of induced neuromodulation, particularly when attempting to modulate corticospinal excitability. However, the modulatory effects of stimulation frequency are not only determined by its absolute value but also by other parameters such as power at harmonics. The stimulus pulse shape further influences parameters such as excitation threshold and fiber selectivity. The explicit role of the power in these harmonics in determining the outcome of stimulation has not previously been analyzed. In this study, we adopted an animal model of peripheral electrical stimulation that includes an amplitude-adapted pulse train which induces force enhancements with a corticospinal contribution. We report that the electrical-stimulation-induced force enhancements were correlated with the amplitude of stimulation power harmonics during the amplitude-adapted pulse train. In an exploratory analysis, different levels of correlation were observed between force enhancement and power harmonics of 20-80 Hz (r = 0.4247, p = 0.0243), 100-180 Hz (r = 0.5894, p = 0.0001), 200-280 Hz (r = 0.7002, p power harmonics. This is a pilot, but important first demonstration that power at high order harmonics in the frequency spectrum of electrical stimulation pulses may contribute to neuromodulation, thus warrant explicit attention in therapy design and analysis.

  8. Soft Encapsulation of Flexible Electrical Stimulation Implant: Challenges and Innovations

    Directory of Open Access Journals (Sweden)

    Adrien Debelle

    2016-11-01

    Full Text Available In this document we discuss the main challenges encountered when producing flexible electrical stimulation implants, and present our approach to solving them for prototype production. We include a study of the optimization of the flexible PCB design, the selection of additive manufacturing materials for the mold, and the chemical compatibility of the different materials. Our approach was tested on a flexible gastro-stimulator as part of the ENDOGES research program.

  9. Prediction and control of neural responses to pulsatile electrical stimulation

    Science.gov (United States)

    Campbell, Luke J.; Sly, David James; O'Leary, Stephen John

    2012-04-01

    This paper aims to predict and control the probability of firing of a neuron in response to pulsatile electrical stimulation of the type delivered by neural prostheses such as the cochlear implant, bionic eye or in deep brain stimulation. Using the cochlear implant as a model, we developed an efficient computational model that predicts the responses of auditory nerve fibers to electrical stimulation and evaluated the model's accuracy by comparing the model output with pooled responses from a group of guinea pig auditory nerve fibers. It was found that the model accurately predicted the changes in neural firing probability over time to constant and variable amplitude electrical pulse trains, including speech-derived signals, delivered at rates up to 889 pulses s-1. A simplified version of the model that did not incorporate adaptation was used to adaptively predict, within its limitations, the pulsatile electrical stimulus required to cause a desired response from neurons up to 250 pulses s-1. Future stimulation strategies for cochlear implants and other neural prostheses may be enhanced using similar models that account for the way that neural responses are altered by previous stimulation.

  10. Ownership of an artificial limb induced by electrical brain stimulation.

    Science.gov (United States)

    Collins, Kelly L; Guterstam, Arvid; Cronin, Jeneva; Olson, Jared D; Ehrsson, H Henrik; Ojemann, Jeffrey G

    2017-01-03

    Replacing the function of a missing or paralyzed limb with a prosthetic device that acts and feels like one's own limb is a major goal in applied neuroscience. Recent studies in nonhuman primates have shown that motor control and sensory feedback can be achieved by connecting sensors in a robotic arm to electrodes implanted in the brain. However, it remains unknown whether electrical brain stimulation can be used to create a sense of ownership of an artificial limb. In this study on two human subjects, we show that ownership of an artificial hand can be induced via the electrical stimulation of the hand section of the somatosensory (SI) cortex in synchrony with touches applied to a rubber hand. Importantly, the illusion was not elicited when the electrical stimulation was delivered asynchronously or to a portion of the SI cortex representing a body part other than the hand, suggesting that multisensory integration according to basic spatial and temporal congruence rules is the underlying mechanism of the illusion. These findings show that the brain is capable of integrating "natural" visual input and direct cortical-somatosensory stimulation to create the multisensory perception that an artificial limb belongs to one's own body. Thus, they serve as a proof of concept that electrical brain stimulation can be used to "bypass" the peripheral nervous system to induce multisensory illusions and ownership of artificial body parts, which has important implications for patients who lack peripheral sensory input due to spinal cord or nerve lesions.

  11. Mapping of electrical muscle stimulation using MRI

    Science.gov (United States)

    Adams, Gregory R.; Harris, Robert T.; Woodard, Daniel; Dudley, Gary A.

    1993-01-01

    The pattern of muscle contractile activity elicited by electromyostimulation (EMS) was mapped and compared to the contractile-activity pattern produced by voluntary effort. This was done by examining the patterns and the extent of contrast shift, as indicated by T2 values, im magnetic resonance (MR) images after isometric activity of the left m. quadriceps of human subjects was elicited by EMS (1-sec train of 500-microsec sine wave pulses at 50 Hz) or voluntary effort. The results suggest that, whereas EMS stimulates the same fibers repeatedly, thereby increasing the metabolic demand and T2 values, the voluntary efforts are performed by more diffuse asynchronous activation of skeletal muscle even at forces up to 75 percent of maximal to maintain performance.

  12. Electrical stimulation counteracts muscle atrophy associated with aging in humans

    Directory of Open Access Journals (Sweden)

    Helmut Kern

    2013-07-01

    Full Text Available Functional and structural muscle decline is a major problem during aging. Our goal was to improve in old subjects quadriceps m. force and mobility functional performances (stair test, chair rise test, timed up and go test with neuromuscular electrical stimulation (9 weeks, 2-3times/week, 20-30 minutes per session. Furthermore we performed histological and biological molecular analyses of vastus lateralis m. biopsies. Our findings demonstrate that electrical stimulation significantly improved mobility functional performancies and muscle histological characteristics and molecular markers.

  13. Determinants of the electric field during transcranial direct current stimulation

    DEFF Research Database (Denmark)

    Opitz, Alexander; Paulus, Walter; Will, Susanne

    2015-01-01

    Transcranial direct current stimulation (tDCS) causes a complex spatial distribution of the electric current flow in the head which hampers the accurate localization of the stimulated brain areas. In this study we show how various anatomical features systematically shape the electric field...... over the motor cortex in small steps to examine the resulting changes of the electric field distribution in the underlying cortex. We examined the effect of skull thickness and composition on the passing currents showing that thinner skull regions lead to higher electric field strengths. This effect...... is counteracted by a larger proportion of higher conducting spongy bone in thicker regions leading to a more homogenous current over the skull. Using a multiple regression model we could identify key factors that determine the field distribution to a significant extent, namely the thicknesses of the cerebrospinal...

  14. Hearing suppression induced by electrical stimulation of human auditory cortex.

    Science.gov (United States)

    Fenoy, Albert J; Severson, Meryl A; Volkov, Igor O; Brugge, John F; Howard, Matthew A

    2006-11-06

    In the course of performing electrical stimulation functional mapping (ESFM) in neurosurgery patients, we identified three subjects who experienced hearing suppression during stimulation of sites within the superior temporal gyrus (STG). One of these patients had long standing tinnitus that affected both ears. In all subjects, auditory event related potentials (ERPs) were recorded from chronically implanted intracranial electrodes and the results were used to localize auditory cortical fields within the STG. Hearing suppression sites were identified within anterior lateral Heschl's gyrus (HG) and posterior lateral STG, in what may be auditory belt and parabelt fields. Cortical stimulation suppressed hearing in both ears, which persisted beyond the period of electrical stimulation. Subjects experienced other stimulation-evoked perceptions at some of these same sites, including symptoms of vestibular activation and alteration of audio-visual speech processing. In contrast, stimulation of presumed core auditory cortex within posterior medial HG evoked sound perceptions, or in one case an increase in tinnitus intensity, that affected the contralateral ear and did not persist beyond the period of stimulation. The current results confirm a rarely reported experimental observation, and correlate the cortical sites associated with hearing suppression with physiologically identified auditory cortical fields.

  15. Investigation of electrical responses to acupuncture stimulation: the effect of electrical grounding and insulation conditions.

    Science.gov (United States)

    Lee, Yong-Heum; Ryu, Yeon-Hang; Jung, Byungjo

    2009-03-01

    Acupuncture in Oriental medicine has been widely used as a core therapeutic method due to its minimal side-effects and therapeutic efficacy. However, the electrical response to acupuncture stimulation (ERAS) has not been clearly studied under acupuncture conditions that might affect the efficacy of acupuncture therapy. In this study, the ERAS was objectively investigated by measuring meridian electric potentials (MEPs) when the electrical grounding conditions of the operator and subject were varied, and when the insulation conditions of acupuncture needle were varied. MEPs between Sang-geoheo (ST37) and Ha-geoheo (ST39) of the Stomach Meridian (ST) were measured by stimulating Jok-samni (ST36) with an acupuncture needle. For non-insulated acupuncture stimulation (NIAS), the average MEP peak was 148.6 +/- 20.6 when neither the operator nor the subject were electrically grounded, 23.1 +/- 8.8 when the subject only was electrically grounded, 348 +/- 76.8 when the operator only was electrically grounded, and 19.9 +/- 4.7 when both the operator and the subject were electrically grounded. The MEPs presented various magnitudes and patterns depending on the electrical grounding conditions. The MEP pattern was very similar to that of the charge and discharge of a capacitor. For insulated acupuncture stimulation (IAS), the average MEP peak was 20 +/- 4 in all electrical grounding conditions, which is not a significant electric response for acupuncture stimulation. In terms of electricity, this study verified that acupuncture therapy might be affected by acupuncture conditions such as (1) the electrical grounding condition of the operator and the subject and (2) the insulation condition of the acupuncture needle.

  16. Motor unit recruitment during neuromuscular electrical stimulation: a critical appraisal.

    Science.gov (United States)

    Bickel, C Scott; Gregory, Chris M; Dean, Jesse C

    2011-10-01

    Neuromuscular electrical stimulation (NMES) is commonly used in clinical settings to activate skeletal muscle in an effort to mimic voluntary contractions and enhance the rehabilitation of human skeletal muscles. It is also used as a tool in research to assess muscle performance and/or neuromuscular activation levels. However, there are fundamental differences between voluntary- and artificial-activation of motor units that need to be appreciated before NMES protocol design can be most effective. The unique effects of NMES have been attributed to several mechanisms, most notably, a reversal of the voluntary recruitment pattern that is known to occur during voluntary muscle contractions. This review outlines the assertion that electrical stimulation recruits motor units in a nonselective, spatially fixed, and temporally synchronous pattern. Additionally, it synthesizes the evidence that supports the contention that this recruitment pattern contributes to increased muscle fatigue when compared with voluntary actions and provides some commentary on the parameters of electrical stimulation as well as emerging technologies being developed to facilitate NMES implementation. A greater understanding of how electrical stimulation recruits motor units, as well as the benefits and limitations of its use, is highly relevant when using this tool for testing and training in rehabilitation, exercise, and/or research.

  17. Electrical stimulation to increase lower esophageal sphincter pressure after POEM.

    Science.gov (United States)

    Ciotola, Franco; Ditaranto, Andres; Bilder, Claudio; Badaloni, Adolfo; Lowenstein, Daniel; Riganti, Juan Martin; Hoppo, Toshitaka; Jobe, Blair; Nachman, Fabio; Nieponice, Alejandro

    2015-01-01

    Postoperative reflux remains to be a challenge for patients with achalasia undergoing Heller myotomy. Similarly, per-oral endoscopic myotomy (POEM) is gaining rapid acceptance but the impossibility of adding a fundoplication is questioned as the main pitfall to control reflux. Electrical stimulation of the lower esophageal sphincter (LES) has emerged as a new alternative for the treatment of reflux disease. The objective of this study was to evaluate the potential benefits of combining electrical stimulation with endoscopic esophageal myotomy to prevent post procedural reflux. Five pigs were subjected to POEM. After myotomy was completed, two electrical leads were implanted at the LES level and electrical stimulation was applied with the Endostim system with a regimen of 215 μs (5 mA amplitude), at 20 Hz for 25 min. LES pressures were recorded with manometry at pre and post-myotomy and after LES stimulation. Myotomy was completed successfully in all cases. Mean pre-myotomy LES pressure was 35.99 ± 8.08 mmHg. After myotomy, the LES pressure significantly dropped to 10.60 ± 3.24 mmHg (p = 0.03). Subsequent to LES-EST, LES pressure significantly increased to 21.74 ± 4.65 mmHg (p = 0.01). The findings of this study show that LES-EST in healthy animals increases LES pressure after POEM procedure, and could be useful tool to minimize gastroesophageal reflux.

  18. Spectral loudness summation for electrical stimulation in cochlear implant users

    NARCIS (Netherlands)

    Theelen-van den Hoek, Femke L.; Boymans, Monique; Dreschler, Wouter A.

    2015-01-01

    This study investigates the effect of spectral loudness summation (SLS) in the electrical domain as perceived by cochlear implant (CI) users. Analogous to SLS in the acoustical domain, SLS was defined as the effect of electrode separation at a fixed overall stimulation rate. Categorical loudness

  19. Modeling auditory-nerve responses to electrical stimulation

    DEFF Research Database (Denmark)

    Joshi, Suyash Narendra; Dau, Torsten; Epp, Bastian

    Cochlear implants (CI) directly stimulate the auditory nerve (AN), bypassing the mechano-electrical transduction in the inner ear. Trains of biphasic, charge balanced pulses (anodic and cathodic) are used as stimuli to avoid damage of the tissue. The pulses of either polarity are capable of produ......Cochlear implants (CI) directly stimulate the auditory nerve (AN), bypassing the mechano-electrical transduction in the inner ear. Trains of biphasic, charge balanced pulses (anodic and cathodic) are used as stimuli to avoid damage of the tissue. The pulses of either polarity are capable......μs, which is large enough to affect the temporal coding of sounds and hence, potentially, the communication abilities of the CI listener. In the present study, two recently proposed models of electric stimulation of the AN [1,2] were considered in terms of their efficacy to predict the spike timing...... for anodic and cathodic stimulation of the AN of cat [3]. The models’ responses to the electrical pulses of various shapes [4,5,6] were also analyzed. It was found that, while the models can account for the firing rates in response to various biphasic pulse shapes, they fail to correctly describe the timing...

  20. Pharyngeal Electrical Stimulation for Treatment of Dysphagia in Subacute Stroke

    DEFF Research Database (Denmark)

    Bath, Philip M W; Scutt, Polly; Love, Jo

    2016-01-01

    BACKGROUND AND PURPOSE: Dysphagia is common after stroke, associated with increased death and dependency, and treatment options are limited. Pharyngeal electric stimulation (PES) is a novel treatment for poststroke dysphagia that has shown promise in 3 pilot randomized controlled trials. METHODS:...

  1. Effects of Electrical Vagal Stimulation and Bilateral Vagotomy on ...

    African Journals Online (AJOL)

    Effect of electrical vagal stimulation and bilateral vagotomy on the flow and electrolyte composition of bile was studied in fasted and anaesthetized male albino Wistar Rats. Entero-hepatic circulation was maintained artificially by continuous infusion of 1% sodium teurocholate. In each experiment, bile was collected at 15 ...

  2. Electrical and mechanical stimulation of cardiac cells and tissue constructs.

    Science.gov (United States)

    Stoppel, Whitney L; Kaplan, David L; Black, Lauren D

    2016-01-15

    The field of cardiac tissue engineering has made significant strides over the last few decades, highlighted by the development of human cell derived constructs that have shown increasing functional maturity over time, particularly using bioreactor systems to stimulate the constructs. However, the functionality of these tissues is still unable to match that of native cardiac tissue and many of the stem-cell derived cardiomyocytes display an immature, fetal like phenotype. In this review, we seek to elucidate the biological underpinnings of both mechanical and electrical signaling, as identified via studies related to cardiac development and those related to an evaluation of cardiac disease progression. Next, we review the different types of bioreactors developed to individually deliver electrical and mechanical stimulation to cardiomyocytes in vitro in both two and three-dimensional tissue platforms. Reactors and culture conditions that promote functional cardiomyogenesis in vitro are also highlighted. We then cover the more recent work in the development of bioreactors that combine electrical and mechanical stimulation in order to mimic the complex signaling environment present in vivo. We conclude by offering our impressions on the important next steps for physiologically relevant mechanical and electrical stimulation of cardiac cells and engineered tissue in vitro. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Comparison of the Effect of Neuromuscular Electrical Stimulation ...

    African Journals Online (AJOL)

    Children with cerebral palsy (CP) often demonstrate poor hand function due to spasticity. Thus spasticity in the wrist and finger flexors poses a great deal of functional limitations. This study was therefore designed to compare the effectiveness of Cryotherapy and Neuromuscular Electrical Stimulation (NMES) on spasticity ...

  4. Electrical field stimulation-induced excitatory responses of ...

    African Journals Online (AJOL)

    The aim of the present study was to investigate the effect of the endothelium on electrical field stimulation (EFS)-induced excitatory responses of pulmonary artery segments from pulmonary hypertensive rats. Methods: Pulmonary hypertension was induced in rats with a single dose of monocrotaline (60 mg/kg) and 21 days ...

  5. Electrical stimulation using kilohertz-frequency alternating current.

    Science.gov (United States)

    Ward, Alex R

    2009-02-01

    Transcutaneous electrical stimulation using kilohertz-frequency alternating current (AC) became popular in the 1950s with the introduction of "interferential currents," promoted as a means of producing depth-efficient stimulation of nerve and muscle. Later, "Russian current" was adopted as a means of muscle strengthening. This article reviews some clinically relevant, laboratory-based studies that offer an insight into the mechanism of action of kilohertz-frequency AC. It provides some answers to the question: "What are the optimal stimulus parameters for eliciting forceful, yet comfortable, electrically induced muscle contractions?" It is concluded that the stimulation parameters commonly used clinically (Russian and interferential currents) are suboptimal for achieving their stated goals and that greater benefit would be obtained using short-duration (2-4 millisecond), rectangular bursts of kilohertz-frequency AC with a frequency chosen to maximize the desired outcome.

  6. Electric stimulation with sinusoids and white noise for neural prostheses

    Directory of Open Access Journals (Sweden)

    Daniel K Freeman

    2010-02-01

    Full Text Available We are investigating the use of novel stimulus waveforms in neural prostheses to determine whether they can provide more precise control over the temporal and spatial pattern of elicited activity as compared to conventional pulsatile stimulation. To study this, we measured the response of retinal ganglion cells to both sinusoidal and white noise waveforms. The use of cell-attached and whole cell patch clamp recordings allowed the responses to be observed without significant obstruction from the stimulus artifact. Electric stimulation with sinusoids elicited robust responses. White noise analysis was used to derive the linear kernel for the ganglion cell’s spiking response as well as for the underlying excitatory currents. These results suggest that in response to electric stimulation, presynaptic retinal neurons exhibit bandpass filtering characteristics with peak response that occur 25ms after onset. The experimental approach demonstrated here may be useful for studying the temporal response properties of other neurons in the CNS.

  7. Power amplifier circuits for functional electrical stimulation systems

    Directory of Open Access Journals (Sweden)

    Delmar Carvalho de Souza

    Full Text Available Abstract Introduction: Functional electrical stimulation (FES is a technique that has been successfully employed in rehabilitation treatment to mitigate problems after spinal cord injury (SCI. One of the most relevant modules in a typical FES system is the power or output amplifier stage, which is responsible for the application of voltage or current pulses of proper intensity to the biological tissue, applied noninvasively via electrodes, placed on the skin surface or inside the muscular tissue, closer to the nervous fibers. The goals of this paper are to describe and discuss about the main power output designs usually employed in transcutaneous functional electrical stimulators as well as safety precautions taken to protect patients. Methods A systematic review investigated the circuits of papers published in IEEE Xplore and ScienceDirect databases from 2000 to 2016. The query terms were “((FES or Functional electric stimulator and (circuit or design” with 274 papers retrieved from IEEE Xplore and 29 from ScienceDirect. After the application of exclusion criteria the amount of papers decreased to 9 and 2 from IEEE Xplore and ScienceDirect, respectively. One paper was inserted in the results as a technological contribution to the field. Therefore, 12 papers presented power stage circuits suitable to stimulate great muscles. Discussion The retrieved results presented relevant circuits with different electronic strategies and circuit components. Some of them considered patient safety strategies or aimed to preserve muscle homeostasis such as biphasic current application, which prevents charge accumulation in stimulated tissues as well as circuits that dealt with electrical impedance variation to keep the electrode-tissue interface within an electrochemical safe regime. The investigation revealed a predominance of design strategies using operational amplifiers in power circuits, current outputs, and safety methods to reduce risks of electrical

  8. Electrical Stimulation of the Retina to Produce Artificial Vision.

    Science.gov (United States)

    Weiland, James D; Walston, Steven T; Humayun, Mark S

    2016-10-14

    Retinal prostheses aim to restore vision to blind individuals suffering from retinal diseases such as retinitis pigmentosa and age-related macular degeneration. These devices function by electrically stimulating surviving retinal neurons, whose activation is interpreted by the brain as a visual percept. Many prostheses are currently under development. They are categorized as epiretinal, subretinal, and suprachoroidal prostheses on the basis of the placement of the stimulating microelectrode array. Each can activate ganglion cells through direct or indirect stimulation. The response of retinal neurons to these modes of stimulation are discussed in detail and are placed in context of the visual percept they are likely to evoke. This article further reviews challenges faced by retinal prosthesis and discusses potential solutions to address them.

  9. Coherent anti-Stokes Raman scattering under electric field stimulation

    Science.gov (United States)

    Capitaine, Erwan; Ould Moussa, Nawel; Louot, Christophe; Lefort, Claire; Pagnoux, Dominique; Duclère, Jean-René; Kaneyasu, Junya F.; Kano, Hideaki; Duponchel, Ludovic; Couderc, Vincent; Leproux, Philippe

    2016-12-01

    We introduce an experiment using electro-CARS, an electro-optical method based on the combination of ultrabroadband multiplex coherent anti-Stokes Raman scattering (M-CARS) spectroscopy and electric field stimulation. We demonstrate that this method can effectively discriminate the resonant CARS signal from the nonresonant background owing to a phenomenon of molecular orientation in the sample medium. Such molecular orientation is intrinsically related to the induction of an electric dipole moment by the applied static electric field. Evidence of the electro-CARS effect is obtained with a solution of n -alkanes (CnH2 n +2 , 15 ≤n ≤40 ), for which an enhancement of the CARS signal-to-noise ratio is achieved in the case of CH2 and CH3 symmetric/asymmetric stretching vibrations. Additionally, an electric-field-induced second-harmonic generation experiment is performed in order to corroborate the orientational organization of molecules due to the electric field excitation. Finally, we use a simple mathematical approach to compare the vibrational information extracted from electro-CARS measurements with spontaneous Raman data and to highlight the impact of electric stimulation on the vibrational signal.

  10. Assessment of Neuromuscular Function Using Percutaneous Electrical Nerve Stimulation.

    Science.gov (United States)

    Rozand, Vianney; Grosprêtre, Sidney; Stapley, Paul J; Lepers, Romuald

    2015-09-13

    Percutaneous electrical nerve stimulation is a non-invasive method commonly used to evaluate neuromuscular function from brain to muscle (supra-spinal, spinal and peripheral levels). The present protocol describes how this method can be used to stimulate the posterior tibial nerve that activates plantar flexor muscles. Percutaneous electrical nerve stimulation consists of inducing an electrical stimulus to a motor nerve to evoke a muscular response. Direct (M-wave) and/or indirect (H-reflex) electrophysiological responses can be recorded at rest using surface electromyography. Mechanical (twitch torque) responses can be quantified with a force/torque ergometer. M-wave and twitch torque reflect neuromuscular transmission and excitation-contraction coupling, whereas H-reflex provides an index of spinal excitability. EMG activity and mechanical (superimposed twitch) responses can also be recorded during maximal voluntary contractions to evaluate voluntary activation level. Percutaneous nerve stimulation provides an assessment of neuromuscular function in humans, and is highly beneficial especially for studies evaluating neuromuscular plasticity following acute (fatigue) or chronic (training/detraining) exercise.

  11. Measurements and models of electric fields in the in vivo human brain during transcranial electric stimulation.

    Science.gov (United States)

    Huang, Yu; Liu, Anli A; Lafon, Belen; Friedman, Daniel; Dayan, Michael; Wang, Xiuyuan; Bikson, Marom; Doyle, Werner K; Devinsky, Orrin; Parra, Lucas C

    2017-02-07

    Transcranial electric stimulation aims to stimulate the brain by applying weak electrical currents at the scalp. However, the magnitude and spatial distribution of electric fields in the human brain are unknown. We measured electric potentials intracranially in ten epilepsy patients and estimated electric fields across the entire brain by leveraging calibrated current-flow models. When stimulating at 2 mA, cortical electric fields reach 0.4 V/m, the lower limit of effectiveness in animal studies. When individual whole-head anatomy is considered, the predicted electric field magnitudes correlate with the recorded values in cortical (r = 0.89) and depth (r = 0.84) electrodes. Accurate models require adjustment of tissue conductivity values reported in the literature, but accuracy is not improved when incorporating white matter anisotropy or different skull compartments. This is the first study to validate and calibrate current-flow models with in vivo intracranial recordings in humans, providing a solid foundation to target stimulation and interpret clinical trials.

  12. Determinants of the electric field during transcranial direct current stimulation.

    Science.gov (United States)

    Opitz, Alexander; Paulus, Walter; Will, Susanne; Antunes, Andre; Thielscher, Axel

    2015-04-01

    Transcranial direct current stimulation (tDCS) causes a complex spatial distribution of the electric current flow in the head which hampers the accurate localization of the stimulated brain areas. In this study we show how various anatomical features systematically shape the electric field distribution in the brain during tDCS. We constructed anatomically realistic finite element (FEM) models of two individual heads including conductivity anisotropy and different skull layers. We simulated a widely employed electrode montage to induce motor cortex plasticity and moved the stimulating electrode over the motor cortex in small steps to examine the resulting changes of the electric field distribution in the underlying cortex. We examined the effect of skull thickness and composition on the passing currents showing that thinner skull regions lead to higher electric field strengths. This effect is counteracted by a larger proportion of higher conducting spongy bone in thicker regions leading to a more homogenous current over the skull. Using a multiple regression model we could identify key factors that determine the field distribution to a significant extent, namely the thicknesses of the cerebrospinal fluid and the skull, the gyral depth and the distance to the anode and cathode. These factors account for up to 50% of the spatial variation of the electric field strength. Further, we demonstrate that individual anatomical factors can lead to stimulation "hotspots" which are partly resistant to electrode positioning. Our results give valuable novel insights in the biophysical foundation of tDCS and highlight the importance to account for individual anatomical factors when choosing an electrode montage. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. A distributed transducer system for functional electrical stimulation

    DEFF Research Database (Denmark)

    Gudnason, Gunnar; Nielsen, Jannik Hammel; Bruun, Erik

    2001-01-01

    Implanted transducers for functional electrical stimulation (FES) powered by inductive links are subject to conflicting requirements arising from low link efficiency, a low power budget and the need for protection of the weak signals against strong RF electromagnetic fields. We propose a solution...... to be affected by the inductive link. Neural stimulators are affected to a lesser degree, but still benefit from the partitioning. As a test case, we have designed a transceiver and a sensor chip which implement this partitioning policy. The transceiver is designed to operate in the 6.78 MHz ISM band...

  14. Modeling auditory-nerve responses to electrical stimulation

    DEFF Research Database (Denmark)

    Joshi, Suyash Narendra; Dau, Torsten; Epp, Bastian

    2014-01-01

    large enough to affect the temporal coding of sounds and hence, potentially, the communication abilities of the CI listener. In the present study, two recently proposed models of electric stimulationof the AN [1, 2, 3] were considered in terms of their efficacy to predict the spike timing for anodic...... andcathodic stimulation of the AN of cat [4]. The models' responses to the electrical pulses of variousshapes [5] were also analyzed. It was found that, while the models can account for the ring rates inresponse to various biphasic pulse shapes, they fail to correctly describe the timing of AP in response...

  15. Surgical approaches to treatment of gastroparesis: gastric electrical stimulation, pyloroplasty, total gastrectomy and enteral feeding tubes.

    Science.gov (United States)

    Sarosiek, Irene; Davis, Brian; Eichler, Evelin; McCallum, Richard W

    2015-03-01

    Gastric electrical stimulation (GES) is neurostimulation; its mechanism of action is affecting central control of nausea and vomiting and enhancing vagal function. GES is a powerful antiemetic available for patients with refractory symptoms of nausea and vomiting from gastroparesis of idiopathic and diabetic causes. GES is not indicated as a way of reducing abdominal pain in gastroparetic patients. The need for introducing a jejunal feeding tube means intensive medical therapies are failing, and is an indication for the implantation of the GES system, which should always be accompanied by a pyloroplasty to guarantee accelerated gastric emptying. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Electrical stimulation affects metabolic enzyme phosphorylation, protease activation and meat tenderization in beef

    DEFF Research Database (Denmark)

    Li, C.B.; Li, J.; Zhou, G.H.

    2012-01-01

    The objective of this study was to investigate the response of sarcoplasmic proteins in bovine longissimus muscle to low-voltage electrical stimulation (ES, 80 V, 35 s) after dressing and its contribution to meat tenderization at early postmortem time. Proteome analysis showed that ES resulted......, as well as pH decline and more preferred pH/temperature decline mode. Finally, ES accelerated meat tenderization with lower (P ... tenderization of beef. Our results suggested the possible importance of activation of µ-calpain, phosphorylation of sarcoplasmic proteins and release of lysosomal enzymes for ES-induced tenderization of beef muscle....

  17. Determination of the threshold acceleration for the gravitropic stimulation of cress roots and hypocotyls

    Science.gov (United States)

    Laurinavičius, R.; Švegždiene, D.; Buchen, B.; Sievers, A.

    To determine the range of the threshold acceleration (a-threshold) for the gravitropic stimulation of Lepidium sativum L. roots and hypocotyls, experiments were performed on a centrifuge-clinostat with two-orthogonal axes. The rotation rate of the clinostat was 4 rpm (centrifuge was from 3 to 17 rpm (3 x 10^-3 to 10^-1 g). The gravitropic response was determined: (i) after growth of roots and hypocotyls in their normal vertical position and subsequent gravitropic stimulation for 3 h by accelerations of 4 x 10^-3 to 10^-1 g, and (ii) after continuous stimulation in the lateral direction by centripetal accelerations of 4 x 10^-3 to 10^-1 g. The a-threshold was defined by an extrapolation of the regression line of R = p + rx, where x was either 1n a or 1/a for 3 h or a continuous stimulation, respectively. The a-threshold estimated after 3 h stimulation was equal to 2.6 x 10^-3 g for roots and 3.1 x 10^-3 g for hypocotyls. The threshold accelerations that were unable to evoke a gravitropic response even with continuous stimulation of cress roots and hypocotyls were approximately 3.1 x 10^-3 g and 3.6 x 10^-3 g, respectively. Increasing the stimulation acceleration up to 4.1 x 10^-3 g led to a statistically confirmed gravitropic response of a definite proportion of both the root and hypocotyl populations. In the experiments where acceleration and stimulation time were variable, the threshold dose (D-threshold) for roots was determined to be about 14 to 22 g x s, depending on the stimulation duration and the range of accelerations. The kinetics of gravitropic response at a near-threshold acceleration (4 x 10^-3 to 1.9 x 10^-2 g) differed from that at 1 g (horizontal stimulation). At low forces, the maximal response dependent on the magnitude of acceleration could not be enhanced by increasing the stimulation time up to at least 210 min.

  18. Neuromuscular electrical stimulation for mobility support of elderly

    Directory of Open Access Journals (Sweden)

    Winfried Mayr

    2015-10-01

    Full Text Available The stimulator for neuromuscular electrical stimulation for mobility support of elderly is not very complicated, but for application within "MOBIL" we have some additional demands to fulfill. First we have specific safety issues for this user group. A powerful compliance management system is crucial not only to guide daily application, but for creating hard data for the scientific outcome. We also need to assure easy handling of the stimulator, because the subjects are generally not able to cope with too difficult and complex motor skills. So, we developed five generations of stimulators and optimizing solutions after field tests. We are already planning the sixth generation with wireless control of the stimulation units by the central main handheld control unit. In a prototype, we have implemented a newly available high capacity memory, a breakthrough in “compliance data storage” as they offer the necessary high storage capacity and fast data handling for an affordable prize. The circuit also contains a 3D accelerometer sensor which acts as a further important safety features: if the control unit drops, this event is detected automatically by the sensor and activates an emergency switch-off that disables the stimulation to avoid associated risks. Further, we have implemented a hardware emergence shutdown and other safety measures. Finally, in the last example muscle torque measurements are referenced with compliance data. In the study normalized maximum voluntary contraction (MVC and maximum stimulation induced contraction (MSC were assessed in regular check-ups along the training period. With additional consideration of adjusted stimulation intensity for training out of the compliance data records we are able to estimate the induced contraction strength, which turned out to amount in average 11% of MVC. This value may seem on a first sight rather low, and ought to be considered in relation to the results at the end of the training period

  19. Neuromuscular Electrical Stimulation for Motor Restoration in Hemiplegia.

    Science.gov (United States)

    Knutson, Jayme S; Fu, Michael J; Sheffler, Lynne R; Chae, John

    2015-11-01

    This article reviews the most common therapeutic and neuroprosthetic applications of neuromuscular electrical stimulation (NMES) for upper and lower extremity stroke rehabilitation. Fundamental NMES principles and purposes in stroke rehabilitation are explained. NMES modalities used for upper and lower limb rehabilitation are described, and efficacy studies are summarized. The evidence for peripheral and central mechanisms of action is also summarized. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Electric field calculations in brain stimulation based on finite elements

    DEFF Research Database (Denmark)

    Windhoff, Mirko; Opitz, Alexander; Thielscher, Axel

    2013-01-01

    The need for realistic electric field calculations in human noninvasive brain stimulation is undisputed to more accurately determine the affected brain areas. However, using numerical techniques such as the finite element method (FEM) is methodologically complex, starting with the creation...... elements. The latter is crucial to guarantee the numerical robustness of the FEM calculations. The pipeline will be released as open-source, allowing for the first time to perform realistic field calculations at an acceptable methodological complexity and moderate costs....

  1. Power amplifier circuits for functional electrical stimulation systems

    OpenAIRE

    Souza, Delmar Carvalho de; Gaiotto, Marcelo do Carmo; Nogueira Neto,Guilherme Nunes; Castro,Maria Claudia Ferrari de; Nohama, Percy

    2017-01-01

    Abstract Introduction: Functional electrical stimulation (FES) is a technique that has been successfully employed in rehabilitation treatment to mitigate problems after spinal cord injury (SCI). One of the most relevant modules in a typical FES system is the power or output amplifier stage, which is responsible for the application of voltage or current pulses of proper intensity to the biological tissue, applied noninvasively via electrodes, placed on the skin surface or inside the muscular ...

  2. Multi-Scale Computational Models for Electrical Brain Stimulation

    Science.gov (United States)

    Seo, Hyeon; Jun, Sung C.

    2017-01-01

    Electrical brain stimulation (EBS) is an appealing method to treat neurological disorders. To achieve optimal stimulation effects and a better understanding of the underlying brain mechanisms, neuroscientists have proposed computational modeling studies for a decade. Recently, multi-scale models that combine a volume conductor head model and multi-compartmental models of cortical neurons have been developed to predict stimulation effects on the macroscopic and microscopic levels more precisely. As the need for better computational models continues to increase, we overview here recent multi-scale modeling studies; we focused on approaches that coupled a simplified or high-resolution volume conductor head model and multi-compartmental models of cortical neurons, and constructed realistic fiber models using diffusion tensor imaging (DTI). Further implications for achieving better precision in estimating cellular responses are discussed. PMID:29123476

  3. Right Median Nerve Electrical Stimulation for Acute Traumatic Coma Patients.

    Science.gov (United States)

    Lei, Jin; Wang, Lei; Gao, Guoyi; Cooper, Edwin; Jiang, Jiyao

    2015-10-15

    The right median nerve as a peripheral portal to the central nervous system can be electrically stimulated to help coma arousal after traumatic brain injury (TBI). The present study set out to examine the efficacy and safety of right median nerve electrical stimulation (RMNS) in a cohort of 437 comatose patients after severe TBI from August 2005 to December 2011. The patients were enrolled 2 weeks after their injury and assigned to the RMNS group (n=221) receiving electrical stimulation for 2 weeks or the control group (n = 216) treated by standard management according to the date of birth in the month. The baseline data were similar. After the 2-week treatment, the RMNS-treated patients demonstrated a more rapid increase of the mean Glasgow Coma Score, although statistical significance was not reached (8.43 ± 4.98 vs. 7.47 ± 5.37, p = 0.0532). The follow-up data at 6-month post-injury showed a significantly higher proportion of patients who regained consciousness (59.8% vs. 46.2%, p = 0.0073). There was a lower proportion of vegetative persons in the RMNS group than in the control group (17.6% vs. 22.0%, p = 0.0012). For persons regaining consciousness, the functional independence measurement (FIM) score was higher among the RMNS group patients (91.45 ± 8.65 vs. 76.23 ± 11.02, p coma in the early phase.

  4. Stimulation of Neurite Outgrowth Using an Electrically Conducting Polymer

    Science.gov (United States)

    Schmidt, Christine E.; Shastri, Venkatram R.; Vacanti, Joseph P.; Langer, Robert

    1997-08-01

    Damage to peripheral nerves often cannot be repaired by the juxtaposition of the severed nerve ends. Surgeons have typically used autologous nerve grafts, which have several drawbacks including the need for multiple surgical procedures and loss of function at the donor site. As an alternative, the use of nerve guidance channels to bridge the gap between severed nerve ends is being explored. In this paper, the electrically conductive polymer--oxidized polypyrrole (PP)--has been evaluated for use as a substrate to enhance nerve cell interactions in culture as a first step toward potentially using such polymers to stimulate in vivo nerve regeneration. Image analysis demonstrates that PC-12 cells and primary chicken sciatic nerve explants attached and extended neurites equally well on both PP films and tissue culture polystyrene in the absence of electrical stimulation. In contrast, PC-12 cells interacted poorly with indium tin oxide (ITO), poly(L-lactic acid) (PLA), and poly(lactic acid-coglycolic acid) surfaces. However, PC-12 cells cultured on PP films and subjected to an electrical stimulus through the film showed a significant increase in neurite lengths compared with ones that were not subjected to electrical stimulation through the film and tissue culture polystyrene controls. The median neurite length for PC-12 cells grown on PP and subjected to an electrical stimulus was 18.14 μ m (n = 5643) compared with 9.5 μ m (n = 4440) for controls. Furthermore, animal implantation studies reveal that PP invokes little adverse tissue response compared with poly(lactic acid-coglycolic acid).

  5. A systematic review investigating the relationship between efficacy and stimulation parameters when using transcutaneous electrical nerve stimulation after knee arthroplasty

    Directory of Open Access Journals (Sweden)

    David Beckwée

    2014-06-01

    Full Text Available Objective: To evaluate the clinical efficacy of transcutaneous electric nerve stimulation in the treatment of postoperative knee arthroplasty pain and to relate these results to the stimulation parameters used. Data Sources: PubMed, Pedro and Web of Knowledge were systematically screened for studies investigating effects of transcutaneous electric nerve stimulation on postoperative knee arthroplasty pain. Review Methods: Studies were screened for their methodological and therapeutical quality. We appraised the influence of the stimulation settings used and indicated whether or not a neurophysiological and/or mechanistic rationale was given for these stimulation settings. Results: A total of 5 articles met the inclusion criteria. In total, 347 patients were investigated. The number of patients who received some form of transcutaneous electric nerve stimulation was 117, and 54 patients received sham transcutaneous electric nerve stimulation. Pain was the primary outcome in all studies. The stimulation settings used in the studies (n = 2 that reported significant effects differed from the others as they implemented a submaximal stimulation intensity. Stimulation parameters were heterogeneous, and only one study provided a rationale for them. Conclusion: This review reveals that an effect of transcutaneous electric nerve stimulation might have been missed due to low methodological and therapeutical quality. Justifying the choice of transcutaneous electric nerve stimulation parameters may improve therapeutical quality.

  6. Realistic Electric Field Mapping of Anisotropic Muscle During Electrical Stimulation Using a Combination of Water Diffusion Tensor and Electrical Conductivity.

    Science.gov (United States)

    Choi, Bup Kyung; Oh, Tong In; Sajib, Saurav Zk; Kim, Jin Woong; Kim, Hyung Joong; Kwon, Oh In; Woo, Eung Je

    2017-04-01

    To realistically map the electric fields of biological tissues using a diffusion tensor magnetic resonance electrical impedance tomography (DT-MREIT) method to estimate tissue response during electrical stimulation. Imaging experiments were performed using chunks of bovine muscle. Two silver wire electrodes were positioned inside the muscle tissue for electrical stimulation. Electric pulses were applied with a 100-V amplitude and 100-μs width using a voltage stimulator. During electrical stimulation, we collected DT-MREIT data from a 3T magnetic resonance imaging scanner. We adopted the projected current density method to calculate the electric field. Based on the relation between the water diffusion tensor and the conductivity tensor, we computed the position-dependent scale factor using the measured magnetic flux density data. Then, a final conductivity tensor map was reconstructed using the multiplication of the water diffusion tensor and the scale factor. The current density images from DT-MREIT data represent the internal current flows that exist not only in the electrodes but also in surrounding regions. The reconstructed electric filed map from our anisotropic conductivity tensor with the projected current density shows coverage that is more than 2 times as wide, and higher signals in both the electrodes and surrounding tissues, than the previous isotropic method owing to the consideration of tissue anisotropy. An electric field map obtained by an anisotropic reconstruction method showed different patterns from the results of the previous isotropic reconstruction method. Since accurate electric field mapping is important to correctly estimate the coverage of the electrical treatment, future studies should include more rigorous validations of the new method through in vivo and in situ experiments.

  7. The facilitation of motor actions by acoustic and electric stimulation.

    Science.gov (United States)

    Marinovic, Welber; Milford, Magdalene; Carroll, Timothy; Riek, Stephan

    2015-12-01

    The presentation of a loud acoustic stimulus during the preparation of motor actions can both speed movement initiation and increase response vigor. Several recent studies have explored this phenomenon as a means to investigate the mechanisms and neural correlates of movement preparation. Here, we sought to determine the generality of this effect across sensory modalities, and in particular whether unexpected somatosensory stimulation can facilitate movements in a manner similar to loud sounds. We show that electric and acoustic stimuli can be similarly effective in inducing the early release of motor actions, in both reaction time and anticipatory timing tasks. Consistent with recent response activation models of motor preparation, we also demonstrate that increasing the intensity of electric stimuli induces both progressive decreases in reaction time and increases in response vigor. Additionally, we show that the early release of motor actions can be induced by electric stimuli targeting predominantly either muscle afferents or skin afferents. Finally, we show that simultaneous acoustic and electric stimulation leads to earlier releases of anticipatory actions than either unimodal stimulus. These findings may lead to new avenues for experimental and clinical exploitation of the effects of accessory sensory information on movement preparation and initiation. © 2015 Society for Psychophysiological Research.

  8. The transcutaneous electrical nerve stimulation of variable frequency intensity has a longer-lasting analgesic action than the burst transcutaneous electrical nerve stimulation in cancer pain

    OpenAIRE

    Schleder, Juliana Carvalho; Verner, Fernanda Aparecida; Mauda, Loriane; Mazzo, Débora Melo; Fernandes, Luiz Cláudio

    2017-01-01

    ABSTRACT BACKGROUND AND OBJECTIVES: Pain is one of the most frequent symptoms in cancer, and physical therapy offers non-invasive methods such as the transcutaneous electrical nerve stimulation for the relief of symptoms. The objective of this study was to compare the effect of the burst transcutaneous electrical nerve stimulation with the transcutaneous electrical nerve stimulation with variable intensity frequency in cancer pain. METHODS: This study was conducted with 53 patients of the H...

  9. Electrical stimulation vs thermal effects in a complex electromagnetic environment.

    Science.gov (United States)

    Paniagua, Jesús M; Rufo, Montaña; Jiménez, Antonio; Antolín, Alicia; Sánchez, Miguel

    2009-08-01

    Studies linking exposure to low levels of radiofrequencies with adverse health effects, notwithstanding their present apparent inconsistency, have contributed to a steady improvement in the quality of evaluating that exposure. In complex electromagnetic environments, with a multitude of emissions of different frequencies acting simultaneously, knowledge of the spectral content is fundamental to evaluating human exposure to non-ionizing radiation. In the present work, we quantify the most significant spectral components in the frequency band 0.5-2200 MHz in an urban area. The measurements were made with a spectrum analyzer and monopole, biconical, and log-periodic antennas. Power density levels were calculated separately for the medium wave, short wave, and frequency modulation radio broadcasting bands, and for the television and GSM, DCS, and UMTS mobile telephony bands. The measured levels were compared with the ICNIRP reference levels for exposure to multiple frequency sources for thermal effects and electrical stimulation. The results showed the criterion limiting exposure on the basis of preventing electrical stimulation of peripheral nerves and muscles to be stricter (exposure quotient 24.7 10(-4)) than that based on thermal considerations (exposure quotient 0.16 10(-4)). The bands that contribute most to the latter are short wave, with 46.2%, and mobile telephony with 32.6% of the total exposure. In a complex electromagnetic environment, knowledge of the radiofrequency spectrum is essential in order to quantify the contribution of each type of emission to the public's exposure. It is also necessary to evaluate the electrical effects as well as the thermal effects because the criterion to limit exposure on the basis of the effect of the electrical stimulation of tissues is stricter than that based on thermal effects.

  10. Electrical stimulation vs thermal effects in a complex electromagnetic environment

    Energy Technology Data Exchange (ETDEWEB)

    Paniagua, Jesus M., E-mail: paniagua@unex.es [Department of Applied Physics, Polytechnic School, University of Extremadura. Avda. de la Universidad s/n, 10071 Caceres (Spain); Rufo, Montana; Jimenez, Antonio; Antolin, Alicia; Sanchez, Miguel [Department of Applied Physics, Polytechnic School, University of Extremadura. Avda. de la Universidad s/n, 10071 Caceres (Spain)

    2009-08-01

    Studies linking exposure to low levels of radiofrequencies with adverse health effects, notwithstanding their present apparent inconsistency, have contributed to a steady improvement in the quality of evaluating that exposure. In complex electromagnetic environments, with a multitude of emissions of different frequencies acting simultaneously, knowledge of the spectral content is fundamental to evaluating human exposure to non-ionizing radiation. In the present work, we quantify the most significant spectral components in the frequency band 0.5-2200 MHz in an urban area. The measurements were made with a spectrum analyzer and monopole, biconical, and log-periodic antennas. Power density levels were calculated separately for the medium wave, short wave, and frequency modulation radio broadcasting bands, and for the television and GSM, DCS, and UMTS mobile telephony bands. The measured levels were compared with the ICNIRP reference levels for exposure to multiple frequency sources for thermal effects and electrical stimulation. The results showed the criterion limiting exposure on the basis of preventing electrical stimulation of peripheral nerves and muscles to be stricter (exposure quotient 24.7 10{sup -4}) than that based on thermal considerations (exposure quotient 0.16 10{sup -4}). The bands that contribute most to the latter are short wave, with 46.2%, and mobile telephony with 32.6% of the total exposure. In a complex electromagnetic environment, knowledge of the radiofrequency spectrum is essential in order to quantify the contribution of each type of emission to the public's exposure. It is also necessary to evaluate the electrical effects as well as the thermal effects because the criterion to limit exposure on the basis of the effect of the electrical stimulation of tissues is stricter than that based on thermal effects.

  11. Perceptual embodiment of prosthetic limbs by transcutaneous electrical nerve stimulation.

    Science.gov (United States)

    Mulvey, Matthew R; Fawkner, Helen J; Radford, Helen E; Johnson, Mark I

    2012-01-01

      In able-bodied participants, it is possible to induce a sense of perceptual embodiment in an artificial hand using a visual-tactile illusion. In amputee patients, electrical stimulation of sensory afferents using transcutaneous electrical nerve stimulation (TENS) has been shown to generate somatic sensations in an amputee's phantom limb(s). However, the effects of TENS on the perceptual embodiment of an artificial limb are not known. Our objective was to investigate the effects of TENS on the perceptual embodiment of an artificial limb in fully intact able-bodied participants.   We used a modified version of the rubber hand illusion presented to 30 able-bodied participants (16 women, 14 men) to convey TENS paresthesia to an artificial hand. TENS electrodes were located over superficial radial nerve on the lateral aspect of the right forearm (1 cm proximal to the wrist), which was hidden from view. TENS intensity was increased to a strong non-painful TENS sensation (electrical paresthesia) was felt beneath the electrodes and projecting into the fingers of the hand. The electrical characteristics of TENS were asymmetric biphasic electrical pulsed waves, continuous pulse pattern, 120 Hz pulse frequency (rate), and 80 µs pulse duration (width).   Participants reported significantly higher intensities of the rubber hand illusion during the two TENS conditions (mean = 5.8, standard deviation = 1.9) compared with the two non-TENS conditions (mean = 4.9, standard deviation = 1.7), p limb, and this can enhance the sense of perceptual embodiment of an artificial hand. Further exploratory studies involving an amputee population are warranted. © 2011 International Neuromodulation Society.

  12. Generation of Electrical Power from Stimulated Muscle Contractions Evaluated

    Science.gov (United States)

    Lewandowski, Beth; Kilgore, Kevin; Ercegovic, David B.

    2004-01-01

    This project is a collaborative effort between NASA Glenn Research Center's Revolutionary Aeropropulsion Concepts (RAC) Project, part of the NASA Aerospace Propulsion and Power Program of the Aerospace Technology Enterprise, and Case Western Reserve University's Cleveland Functional Electrical Stimulation (FES) Center. The RAC Project foresees implantable power requirements for future applications such as organically based sensor platforms and robotics that can interface with the human senses. One of the goals of the FES Center is to develop a totally implantable neural prosthesis. This goal is based on feedback from patients who would prefer a system with an internal power source over the currently used system with an external power source. The conversion system under investigation would transform the energy produced from a stimulated muscle contraction into electrical energy. We hypothesize that the output power of the system will be greater than the input power necessary to initiate, sustain, and control the electrical conversion system because of the stored potential energy of the muscle. If the system can be made biocompatible, durable, and with the potential for sustained use, then the biological power source will be a viable solution.

  13. Transcranial direct current stimulation accelerates allocentric target detection.

    Science.gov (United States)

    Medina, Jared; Beauvais, Jacques; Datta, Abhishek; Bikson, Marom; Coslett, H Branch; Hamilton, Roy H

    2013-05-01

    Previous research on hemispatial neglect has provided evidence for dissociable mechanisms for egocentric and allocentric processing. Although a few studies have examined whether tDCS to posterior parietal cortex can be beneficial for attentional processing in neurologically intact individuals, none have examined the potential effect of tDCS on allocentric and/or egocentric processing. Our objective was to examine whether transcranial direct current stimulation (tDCS), a noninvasive brain stimulation technique that can increase (anodal) or decrease (cathodal) cortical activity, can affect visuospatial processing in an allocentric and/or egocentric frame of reference. We tested healthy individuals on a target detection task in which the target--a circle with a gap--was either to the right or left of the viewer (egocentric), or contained a gap on the right or left side of the circle (allocentric). Individuals performed the task before, during, and after tDCS to the posterior parietal cortex in one of three stimulation conditions--right anodal/left cathodal, right cathodal/left anodal, and sham. We found an allocentric hemispatial effect both during and after tDCS, such that right anodal/left cathodal tDCS resulted in faster reaction times for detecting stimuli with left-sided gaps compared to right-sided gaps. Our study suggests that right anodal/left cathodal tDCS has a facilitatory effect on allocentric visuospatial processing, and might be useful as a therapeutic technique for individuals suffering from allocentric neglect. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. [Mechanisms and applications of transcutaneous electrical nerve stimulation in analgesia].

    Science.gov (United States)

    Tang, Zheng-Yu; Wang, Hui-Quan; Xia, Xiao-Lei; Tang, Yi; Peng, Wei-Wei; Hu, Li

    2017-06-25

    Transcutaneous electrical nerve stimulation (TENS), as a non-pharmacological and non-invasive analgesic therapy with low-cost, has been widely used to relieve pain in various clinical applications, by delivering current pulses to the skin area to activate the peripheral nerve fibers. Nevertheless, analgesia induced by TENS varied in the clinical practice, which could be caused by the fact that TENS with different stimulus parameters has different biological mechanisms in relieving pain. Therefore, to advance our understanding of TENS in various basic and clinical studies, we discussed (1) neurophysiological and biochemical mechanisms of TENS-induced analgesia; (2) relevant factors that may influence analgesic effects of TENS from the perspectives of stimulus parameters, including stimulated position, pulse parameters (current intensity, frequency, and pulse width), stimulus duration and used times in each day; and (3) applications of TENS in relieving clinical pain, including post-operative pain, chronic low back pain and labor pain. Finally, we propose that TENS may involve multiple and complex psychological neurophysiological mechanisms, and suggest that different analgesic effects of TENS with different stimulus parameters should be taken into consideration in clinical applications. In addition, to optimize analgesic effect, we recommend that individual-based TENS stimulation parameters should be designed by considering individual differences among patients, e.g., adaptively adjusting the stimulation parameters based on the dynamic ratings of patients' pain.

  15. Technical Rebuilding of Movement Function Using Functional Electrical Stimulation

    Science.gov (United States)

    Gföhler, Margit

    To rebuild lost movement functions, neuroprostheses based on functional electrical stimulation (FES) artificially activate skeletal muscles in corresponding sequences, using both residual body functions and artificial signals for control. Besides the functional gain, FES training also brings physiological and psychological benefits for spinal cord-injured subjects. In this chapter, current stimulation technology and the main components of FES-based neuroprostheses including enhanced control systems are presented. Technology and application of FES cycling and rowing, both approaches that enable spinal cord-injured subjects to participate in mainstream activities and improve their health and fitness by exercising like able-bodied subjects, are discussed in detail, and an overview of neuroprostheses that aim at restoring movement functions for daily life as walking or grasping is given.

  16. Designing electrical stimulated bioreactors for nerve tissue engineering

    Science.gov (United States)

    Sagita, Ignasius Dwi; Whulanza, Yudan; Dhelika, Radon; Nurhadi, Ibrahim

    2018-02-01

    Bioreactor provides a biomimetic ecosystem that is able to culture cells in a physically controlled system. In general, the controlled-parameters are temperature, pH, fluid flow, nutrition flow, etc. In this study, we develop a bioreactor that specifically targeted to culture neural stem cells. This bioreactor could overcome some limitations of conventional culture technology, such as petri dish, by providing specific range of observation area and a uniform treatment. Moreover, the microfluidic bioreactor, which is a small-controlled environment, is able to observe as small number of cells as possible. A perfusion flow is applied to mimic the physiological environment in human body. Additionally, this bioreactor also provides an electrical stimulation which is needed by neural stem cells. In conclusion, we found the correlation between the induced shear stress with geometric parameters of the bioreactor. Ultimately, this system shall be used to observe the interaction between stimulation and cell growth.

  17. Bio-robots automatic navigation with electrical reward stimulation.

    Science.gov (United States)

    Sun, Chao; Zhang, Xinlu; Zheng, Nenggan; Chen, Weidong; Zheng, Xiaoxiang

    2012-01-01

    Bio-robots that controlled by outer stimulation through brain computer interface (BCI) suffer from the dependence on realtime guidance of human operators. Current automatic navigation methods for bio-robots focus on the controlling rules to force animals to obey man-made commands, with animals' intelligence ignored. This paper proposes a new method to realize the automatic navigation for bio-robots with electrical micro-stimulation as real-time rewards. Due to the reward-seeking instinct and trial-and-error capability, bio-robot can be steered to keep walking along the right route with rewards and correct its direction spontaneously when rewards are deprived. In navigation experiments, rat-robots learn the controlling methods in short time. The results show that our method simplifies the controlling logic and realizes the automatic navigation for rat-robots successfully. Our work might have significant implication for the further development of bio-robots with hybrid intelligence.

  18. Photoacoustic microscopy of microvascular responses to cortical electrical stimulation

    Science.gov (United States)

    Tsytsarev, Vassiliy; Hu, Song; Yao, Junjie; Maslov, Konstantin; Barbour, Dennis L.; Wang, Lihong V.

    2011-07-01

    Advances in the functional imaging of cortical hemodynamics have greatly facilitated the understanding of neurovascular coupling. In this study, label-free optical-resolution photoacoustic microscopy (OR-PAM) was used to monitor microvascular responses to direct electrical stimulations of the mouse somatosensory cortex through a cranial opening. The responses appeared in two forms: vasoconstriction and vasodilatation. The transition between these two forms of response was observed in single vessels by varying the stimulation intensity. Marked correlation was found between the current-dependent responses of two daughter vessels bifurcating from the same parent vessel. Statistical analysis of twenty-seven vessels from three different animals further characterized the spatial-temporal features and the current dependence of the microvascular response. Our results demonstrate that OR-PAM is a valuable tool to study neurovascular coupling at the microscopic level.

  19. Preventing Ischial Pressure Ulcers: I. Review of Neuromuscular Electrical Stimulation

    Directory of Open Access Journals (Sweden)

    Hilton M. Kaplan

    2011-01-01

    Full Text Available Objective: Pressure ulcers (PUs are common and debilitating wounds that arise when immobilized patients cannot shift their weight. Treatment is expensive and recurrence rates are high. Pathophysiological mechanisms include reduced bulk and perfusion of chronically atrophic muscles as well as prolonged occlusion of blood flow to soft tissues from lack of voluntary postural shifting of body weight. This has suggested that PUs might be prevented by reanimating the paralyzed muscles using neuromuscular electrical stimulation (NMES. A review of the published literature over the past 2 decades is detailed.

  20. Gastric electrical stimulation: a report of two cases.

    LENUS (Irish Health Repository)

    Sibartie, V

    2012-02-03

    Gastroparesis refractory to prokinetic agents poses a major challenge to the physician and patient, alike. In the past 5 years, electrical methods to treat gastroparesis have emerged from animal and human experiments to a potentially valuable tool in clinical gastroenterology. One of these methods, known as gastric electrical stimulation (GES), is being increasingly used in specialized centres worldwide, but had never been tried in Ireland. We describe here our experience with the first two implantations of gastric neurostimulators performed in Ireland and the outcome with these 2 patients. Our results at 6 months show reduction in symptoms and improvement in quality of life, which is encouraging and should prompt further evaluation of GES for patients with gastroparesis refractory to medical therapy.

  1. Transcutaneous electric nerve stimulation (TENS) in dentistry- A review.

    Science.gov (United States)

    Kasat, Vikrant; Gupta, Aditi; Ladda, Ruchi; Kathariya, Mitesh; Saluja, Harish; Farooqui, Anjum-Ara

    2014-12-01

    Transcutaneous electric nerve stimulation (TENS) is a non-pharmacological method which is widely used by medical and paramedical professionals for the management of acute and chronic pain in a variety of conditions. Similarly, it can be utilized for the management of pain during various dental procedures as well as pain due to various conditions affecting maxillofacial region. This review aims to provide an insight into clinical research evidence available for the analgesic and non analgesic uses of TENS in pediatric as well as adult patients related to the field of dentistry. Also, an attempt is made to briefly discuss history of therapeutic electricity, mechanism of action of TENS, components of TENs equipment, types, techniques of administration, advantages and contradictions of TENS. With this we hope to raise awareness among dental fraternity regarding its dental applications thereby increasing its use in dentistry. Key words:Dentistry, pain, TENS.

  2. Research on Acceleration Compensation Strategy of Electric Vehicle Based on Fuzzy Control Theory

    Science.gov (United States)

    Zhu, Tianjun; Li, Bin; Zong, Changfu; Wei, Zhicheng

    2017-09-01

    Nowadays, the driving technology of electric vehicle is developing rapidly. There are many kinds of methods in driving performance control technology. The paper studies the acceleration performance of electric vehicle. Under the premise of energy management, an acceleration power compensation method by fuzzy control theory based on driver intention recognition is proposed, which can meet the driver’s subjective feelings better. It avoids the problem that the pedal opening and power output are single correspondence when the traditional vehicle accelerates. Through the simulation test, this method can significantly improve the performance of acceleration and output torque smoothly in non-emergency acceleration to ensure vehicle comfortable and stable.

  3. Neuromuscular Fatigue After Repeated Jumping With Concomitant Electrical Stimulation.

    Science.gov (United States)

    Neyroud, Daria; Samararatne, Jimmy; Kayser, Bengt; Place, Nicolas

    2017-12-18

    To evaluate the etiology and extent of neuromuscular fatigue induced by 50 squat jumps performed with and without neuromuscular electrical stimulation (NMES) of the knee extensors. Nine healthy, recreationally active men (24 ± 2 y) took part in 2 experiments. These consisted of 50 squat jumps performed with stimulation (NMES) or without (CON). Maximal voluntary contraction (MVC) force, maximal voluntary activation level (VAL), and forces evoked by single and double (10 and 100 Hz) stimulations were recorded before and after the 50 jumps. NMES was delivered at the maximal tolerated intensity. Despite average jump height being ∼16% lower in the NMES than in the CON session, a reduction over time in jump height was only found in the NMES condition (-6%). After the 50 jumps, MVC force was reduced to a greater extent in NMES than in CON (-25% ± 11% vs -11% ± 12%). Similarly, forces evoked by single stimulations, as well as by 10-Hz and 100-Hz paired stimulations, were reduced to a greater extent in NMES (-33% ± 12%, -42% ± 15%, and -25% ± 13%) than in CON (-21% ± 6%, -30% ± 9%, and -14% ± 11%). VAL was not significantly altered by either condition. Performing repeated squat jumps with concomitant NMES induced a greater fatigue than squat jumps performed alone and might potentially represent a stronger training stimulus.

  4. A systematic review of electric-acoustic stimulation: device fitting ranges, outcomes, and clinical fitting practices.

    Science.gov (United States)

    Incerti, Paola V; Ching, Teresa Y C; Cowan, Robert

    2013-03-01

    Cochlear implant systems that combine electric and acoustic stimulation in the same ear are now commercially available and the number of patients using these devices is steadily increasing. In particular, electric-acoustic stimulation is an option for patients with severe, high frequency sensorineural hearing impairment. There have been a range of approaches to combining electric stimulation and acoustic hearing in the same ear. To develop a better understanding of fitting practices for devices that combine electric and acoustic stimulation, we conducted a systematic review addressing three clinical questions: what is the range of acoustic hearing in the implanted ear that can be effectively preserved for an electric-acoustic fitting?; what benefits are provided by combining acoustic stimulation with electric stimulation?; and what clinical fitting practices have been developed for devices that combine electric and acoustic stimulation? A search of the literature was conducted and 27 articles that met the strict evaluation criteria adopted for the review were identified for detailed analysis. The range of auditory thresholds in the implanted ear that can be successfully used for an electric-acoustic application is quite broad. The effectiveness of combined electric and acoustic stimulation as compared with electric stimulation alone was consistently demonstrated, highlighting the potential value of preservation and utilization of low frequency hearing in the implanted ear. However, clinical procedures for best fitting of electric-acoustic devices were varied. This clearly identified a need for further investigation of fitting procedures aimed at maximizing outcomes for recipients of electric-acoustic devices.

  5. [Efficacy observation of dysphagia after acute stroke treated with acupuncture and functional electric stimulation].

    Science.gov (United States)

    Chang, Ling; He, Peng-Lan; Zhou, Zhen-Zhong; Li, Yan-Hua

    2014-08-01

    To observe the impacts on the recovery of swallowing function in patients of dysphagia after acute stroke treated with acupuncture and functional electric stimulation. Seventy-four patients were randomized into an acupuncture plus electric stimulation group (38 cases) and an electric stimulation group (36 cases). The functional electric stimulator was used in the two groups. The electric pads were placed on the hyoid bone, the upper part of thyroid cartilage, the masseter muscle and the mandibular joint. The treatment lasted for 30 mm each time. In the acupuncture plus electric stimulation group, acupuncture was supplemented at motor area of Jiao's scalp acupuncture, lower 2/5 of sensory area, Baihui (CV 20), Lianquan (CV 23), Jinjin (EX-HN 12) and Yuye (EX-HN 13), 30 mm each time. The treatment was given once a day, 6 treatments for one session and there was 1 day at interval between the sessions, 4 sessions were required totally in the two groups. The dysphagia scale was adopted for efficacy evaluation before treatment and after 4 sessions of treatment in the two groups. The removal rate of nasal feeding tube was observed after treatment. The dysphagia score was increased apparently after treatment compared with that before treatment in the two groups (both P electric stimulation group, the dysphagia score was increased much more apparently than that in the electric stimulation group (8.01 +/- 1.25 vs 6.73 +/- 1.36, P electric stimulation group, better than 58.3% (21/36) in the electric stimulation group (P electric stimulation group, which was higher than 50. 0% (18/36) in the electric stimulation group (P electric stimulation achieves the much better efficacy on dysphagia after acute stroke and promotes the early removal of nasal feeding tube. The efficacy is better than that of the simple electric stimulation therapy.

  6. Comparison of electrode sites in electrical stimulation of the cochlea.

    Science.gov (United States)

    Lusted, H S; Shelton, C; Simmons, F B

    1984-07-01

    There is considerable controversy about the "best" location for single channel cochlear implant electrodes. We measured the electrically induced auditory brain stem response (EABR) in a series of normal to totally denervated cat ears in response to promontory (P), round window (RW) and scala tympani (ST) stimulation. The status of the ganglion cell population was then assessed by light microscopy. In ears with light to medium ganglion cell loss the ST EABR yielded the most definitive input-output functions. RW responses were present at increased thresholds and smaller peak amplitudes. P responses were worse or even missing completely. In severely damaged ears, including some with no detectable ganglion cells, ST and RW EABRs were both markedly reduced with considerable overlap between the two sites. P responses, when present, were almost buried in the electrical noise near threshold. Extrapolating these results to humans suggests that when ganglion cell loss is very severe the RW or ST is an acceptable stimulation site. When ganglion cell loss is moderate or better, ST electrodes are superior.

  7. BCI-Triggered functional electrical stimulation therapy for upper limb

    Directory of Open Access Journals (Sweden)

    Cesar Marquez-Chin

    2016-08-01

    Full Text Available We present here the integration of brain-computer interfacing (BCI technology with functional electrical stimulation therapy to restore voluntary function. The system was tested with a single man with chronic (6 years severe left hemiplegia resulting from a stroke. The BCI, implemented as a simple “brain-switch” activated by power decreases in the 18 Hz – 28 Hz frequency range of the participant’s electroencephalograpic signals, triggered a neuroprosthesis designed to facilitate forward reaching, reaching to the mouth, and lateral reaching movements. After 40 90-minute sessions in which the participant attempted the reaching tasks repeatedly, with the movements assisted by the BCI-triggered neuroprosthesis, the participant’s arm function showed a clinically significant six point increase in the Fugl-Meyer Asessment Upper Extermity Sub-Score. These initial results suggest that the combined use of BCI and functional electrical stimulation therapy may restore voluntary reaching function in individuals with chronic severe hemiplegia for whom the rehabilitation alternatives are very limited.

  8. Sex and Electrode Configuration in Transcranial Electrical Stimulation

    Directory of Open Access Journals (Sweden)

    Michael J. Russell

    2017-08-01

    Full Text Available Transcranial electrical stimulation (tES can be an effective non-invasive neuromodulation procedure. Unfortunately, the considerable variation in reported treatment outcomes, both within and between studies, has made the procedure unreliable for many applications. To determine if individual differences in cranium morphology and tissue conductivity can account for some of this variation, the electrical density at two cortical locations (temporal and frontal directly under scalp electrodes was modeled using a validated MRI modeling procedure in 23 subjects (12 males and 11 females. Three different electrode configurations (non-cephalic, bi-cranial, and ring commonly used in tES were modeled at three current intensities (0.5, 1.0, and 2.0 mA. The aims were to assess the effects of configuration and current intensity on relative current received at a cortical brain target directly under the stimulating electrode and to characterize individual variation. The different electrode configurations resulted in up to a ninefold difference in mean current densities delivered to the brains. The ring configuration delivered the least current and the non-cephalic the most. Female subjects showed much less current to the brain than male subjects. Individual differences in the current received and differences in electrode configurations may account for significant variability in current delivered and, thus, potentially a significant portion of reported variation in clinical outcomes at two commonly targeted regions of the brain.

  9. BCI-Triggered Functional Electrical Stimulation Therapy for Upper Limb

    Science.gov (United States)

    Marquez-Chin, Cesar; Marquis, Aaron; Popovic, Milos R.

    2016-01-01

    We present here the integration of brain-computer interfacing (BCI) technology with functional electrical stimulation therapy to restore voluntary function. The system was tested with a single man with chronic (6 years) severe left hemiplegia resulting from a stroke. The BCI, implemented as a simple “brain-switch” activated by power decreases in the 18 Hz – 28 Hz frequency range of the participant’s electroencephalograpic signals, triggered a neuroprosthesis designed to facilitate forward reaching, reaching to the mouth, and lateral reaching movements. After 40 90-minute sessions in which the participant attempted the reaching tasks repeatedly, with the movements assisted by the BCI-triggered neuroprosthesis, the participant’s arm function showed a clinically significant six point increase in the Fugl-Meyer Asessment Upper Extermity Sub-Score. These initial results suggest that the combined use of BCI and functional electrical stimulation therapy may restore voluntary reaching function in individuals with chronic severe hemiplegia for whom the rehabilitation alternatives are very limited. PMID:27990247

  10. Spatiotemporal structure of intracranial electric fields induced by transcranial electric stimulation in humans and nonhuman primates

    DEFF Research Database (Denmark)

    Opitz, Alexander; Falchier, Arnaud; Yan, Chao-Gan

    2016-01-01

    Transcranial electric stimulation (TES) is an emerging technique, developed to non-invasively modulate brain function. However, the spatiotemporal distribution of the intracranial electric fields induced by TES remains poorly understood. In particular, it is unclear how much current actually...... reaches the brain, and how it distributes across the brain. Lack of this basic information precludes a firm mechanistic understanding of TES effects. In this study we directly measure the spatial and temporal characteristics of the electric field generated by TES using stereotactic EEG (s-EEG) electrode...... arrays implanted in cebus monkeys and surgical epilepsy patients. We found a small frequency dependent decrease (10%) in magnitudes of TES induced potentials and negligible phase shifts over space. Electric field strengths were strongest in superficial brain regions with maximum values of about 0.5 m...

  11. Anatomically based lower limb nerve model for electrical stimulation

    Directory of Open Access Journals (Sweden)

    Soboleva Tanya K

    2007-12-01

    Full Text Available Abstract Background Functional Electrical Stimulation (FES is a technique that aims to rehabilitate or restore functionality of skeletal muscles using external electrical stimulation. Despite the success achieved within the field of FES, there are still a number of questions that remain unanswered. One way of providing input to the answers is through the use of computational models. Methods This paper describes the development of an anatomically based computer model of the motor neurons in the lower limb of the human leg and shows how it can be used to simulate electrical signal propagation from the beginning of the sciatic nerve to a skeletal muscle. One-dimensional cubic Hermite finite elements were used to represent the major portions of the lower limb nerves. These elements were fit to data that had been digitised using images from the Visible Man project. Nerves smaller than approximately 1 mm could not be seen in the images, and thus a tree-branching algorithm was used to connect the ends of the fitted nerve model to the respective skeletal muscle. To simulate electrical propagation, a previously published mammalian nerve model was implemented and solved on the anatomically based nerve mesh using a finite difference method. The grid points for the finite difference method were derived from the fitted finite element mesh. By adjusting the tree-branching algorithm, it is possible to represent different levels of motor-unit recruitment. Results To illustrate the process of a propagating nerve stimulus to a muscle in detail, the above method was applied to the nerve tree that connects to the human semitendinosus muscle. A conduction velocity of 89.8 m/s was obtained for a 15 μm diameter nerve fibre. This signal was successfully propagated down the motor neurons to a selected group of motor units in the muscle. Conclusion An anatomically and physiologically based model of the posterior motor neurons in the human lower limb was developed. This

  12. Transcutaneous electrical nerve stimulation for spasticity: A systematic review.

    Science.gov (United States)

    Fernández-Tenorio, E; Serrano-Muñoz, D; Avendaño-Coy, J; Gómez-Soriano, J

    2016-07-26

    Although transcutaneous electrical nerve stimulation (TENS) has traditionally been used to treat pain, some studies have observed decreased spasticity after use of this technique. However, its use in clinical practice is still limited. Our purpose was twofold: to determine whether TENS is effective for treating spasticity or associated symptoms in patients with neurological involvement, and to determine which stimulation parameters exert the greatest effect on variables associated with spasticity. Two independent reviewers used PubMed, PEDro, and Cochrane databases to search for randomised clinical trials addressing TENS and spasticity published before 12 May 2015, and selected the articles that met the inclusion criteria. Of the initial 96 articles, 86 were excluded. The remaining 10 articles present results from 207 patients with a cerebrovascular accident, 84 with multiple sclerosis, and 39 with spinal cord lesions. In light of our results, we recommend TENS as a treatment for spasticity due to its low cost, ease of use, and absence of adverse reactions. However, the great variability in the types of stimulation used in the studies, and the differences in parameters and variables, make it difficult to assess and compare any results that might objectively determine the effectiveness of this technique and show how to optimise parameters. Copyright © 2016 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  13. Electrical nerve stimulation to promote micturition in spinal cord injury patients: A review of current attempts.

    Science.gov (United States)

    Ren, Jian; Chew, Daniel J; Biers, Suzanne; Thiruchelvam, Nikesh

    2016-03-01

    In this review, we focus on the current attempts of electrical nerve stimulation for micturition in spinal cord injury (SCI) patients. A literature search was performed through PubMed using "spinal cord injury," "electrical nerve stimulation AND bladder," "sacral anterior root stimulation/stimulator" and "Brindley stimulator" from January 1975 to January 2014. Twenty studies were selected for this review. Electrical nerve stimulation is a clinical option for promoting micturition in SCI patients. Well-designed, randomized and controlled studies are essential for further investigation. © 2015 Wiley Periodicals, Inc.

  14. Electrical stimulation does not enhance nerve regeneration if delayed after sciatic nerve injury: the role of fibrosis

    Directory of Open Access Journals (Sweden)

    Na Han

    2015-01-01

    Full Text Available Electrical stimulation has been shown to accelerate and enhance nerve regeneration in sensory and motor neurons after injury, but there is little evidence that focuses on the varying degrees of fibrosis in the delayed repair of peripheral nerve tissue. In this study, a rat model of sciatic nerve transection injury was repaired with a biodegradable conduit at 1 day, 1 week, 1 month and 2 months after injury, when the rats were divided into two subgroups. In the experimental group, rats were treated with electrical stimuli of frequency of 20 Hz, pulse width 100 ms and direct current voltage of 3 V; while rats in the control group received no electrical stimulation after the conduit operation. Histological results showed that stained collagen fibers comprised less than 20% of the total operated area in the two groups after delayed repair at both 1 day and 1 week but after longer delays, the collagen fiber area increased with the time after injury. Immunohistochemical staining revealed that the expression level of transforming growth factor β (an indicator of tissue fibrosis decreased at both 1 day and 1 week after delayed repair but increased at both 1 and 2 months after delayed repair. These findings indicate that if the biodegradable conduit repair combined with electrical stimulation is delayed, it results in a poor outcome following sciatic nerve injury. One month after injury, tissue degeneration and distal fibrosis are apparent and are probably the main reason why electrical stimulation fails to promote nerve regeneration after delayed repair.

  15. Electrical stimulation: a novel tool for tissue engineering.

    Science.gov (United States)

    Balint, Richard; Cassidy, Nigel J; Cartmell, Sarah H

    2013-02-01

    New advances in tissue engineering are being made through the application of different types of electrical stimuli to influence cell proliferation and differentiation. Developments made in the last decade have allowed us to improve the structure and functionality of tissue-engineered products through the use of growth factors, hormones, drugs, physical stimuli, bioreactor use, and two-dimensional (2-D) and three-dimensional (3-D) artificial extracellular matrices (with various material properties and topography). Another potential type of stimulus is electricity, which is important in the physiology and development of the majority of all human tissues. Despite its great potential, its role in tissue regeneration and its ability to influence cell migration, orientation, proliferation, and differentiation has rarely been considered in tissue engineering. This review highlights the importance of endogenous electrical stimulation, gathering the current knowledge on its natural occurrence and role in vivo, discussing the novel methods of delivering this stimulus and examining its cellular and tissue level effects, while evaluating how the technique could benefit the tissue engineering discipline in the future.

  16. Modulation of Illusory Auditory Perception by Transcranial Electrical Stimulation

    Directory of Open Access Journals (Sweden)

    Giulia Prete

    2017-06-01

    Full Text Available The aim of the present study was to test whether transcranial electrical stimulation can modulate illusory perception in the auditory domain. In two separate experiments we applied transcranial Direct Current Stimulation (anodal/cathodal tDCS, 2 mA; N = 60 and high-frequency transcranial Random Noise Stimulation (hf-tRNS, 1.5 mA, offset 0; N = 45 on the temporal cortex during the presentation of the stimuli eliciting the Deutsch's illusion. The illusion arises when two sine tones spaced one octave apart (400 and 800 Hz are presented dichotically in alternation, one in the left and the other in the right ear, so that when the right ear receives the high tone, the left ear receives the low tone, and vice versa. The majority of the population perceives one high-pitched tone in one ear alternating with one low-pitched tone in the other ear. The results revealed that neither anodal nor cathodal tDCS applied over the left/right temporal cortex modulated the perception of the illusion, whereas hf-tRNS applied bilaterally on the temporal cortex reduced the number of times the sequence of sounds is perceived as the Deutsch's illusion with respect to the sham control condition. The stimulation time before the beginning of the task (5 or 15 min did not influence the perceptual outcome. In accordance with previous findings, we conclude that hf-tRNS can modulate auditory perception more efficiently than tDCS.

  17. Comparison of electrical nerve stimulation, electrical muscle stimulation and magnetic nerve stimulation to assess the neuromuscular function of the plantar flexor muscles.

    Science.gov (United States)

    Neyroud, Daria; Temesi, John; Millet, Guillaume Y; Verges, Samuel; Maffiuletti, Nicola A; Kayser, Bengt; Place, Nicolas

    2015-07-01

    As it might lead to less discomfort, magnetic nerve stimulation (MNS) is increasingly used as an alternative to electrical stimulation methods. Yet, MNS and electrical nerve stimulation (ENS) and electrical muscle stimulation (EMS) have not been formally compared for the evaluation of plantar flexor neuromuscular function. We quantified plantar flexor neuromuscular function with ENS, EMS and MNS in 10 volunteers in fresh and fatigued muscles. Central alterations were assessed through changes in voluntary activation level (VAL) and peripheral function through changes in M-wave, twitch and doublet (PS100) amplitudes. Discomfort associated with 100-Hz paired stimuli delivered with each method was evaluated on a 10-cm visual analog scale. VAL, agonist and antagonist M-wave amplitudes and PS100 were similar between the different methods in both fresh and fatigued states. Potentiated peak twitch was lower in EMS compared to ENS, whereas no difference was found between ENS and MNS for any parameter. Discomfort associated with MNS (1.5 ± 1.4 cm) was significantly less compared to ENS (5.5 ± 1.9 cm) and EMS (4.2 ± 2.6 cm) (p evaluate neuromuscular properties, MNS, EMS and ENS can be used interchangeably for plantar flexor neuromuscular function assessment as they provide similar evaluation of central and peripheral factors in unfatigued and fatigued states. Importantly, electrical current spread to antagonist muscles was similar between the three methods while discomfort from MNS was much less compared to ENS and EMS. MNS may be potentially employed to assess neuromuscular function of plantar flexor muscles in fragile populations.

  18. Development of Functional Electrical Stimulation Rowing: The Rowstim Series.

    Science.gov (United States)

    Andrews, Brian; Gibbons, Robin; Wheeler, Garry

    2017-11-01

    Potentially, functional electrical stimulation (FES)-assisted exercise may have an important therapeutic role in reducing comorbidities associated with spinal cord injury (SCI). Here, we present an overview of these secondary life-threatening conditions, discuss the rationale behind the development of a hybrid exercise called FES rowing, and describe our experience in developing FES rowing technology. FES rowing and sculling are unique forms of adaptive rowing for those with SCI. The paralyzed leg musculature is activated by multiple channels of electrical pulses delivered via self-adhesive electrodes attached to the skin. The stimulated muscle contractions are synchronized with voluntary rowing movements of the upper limbs. A range of steady-state FES rowing exercise intensities have been demonstrated from 15.2 ± 1.8 mL/kg/min in tetraplegia to 22.9 ±7.1 mL/kg/min in paraplegia. We expect that such high levels may help some to achieve significant reductions in the risks to their health, particularly where a dose-response relationship exists as is the case for cardiovascular disease and Type II diabetes. Furthermore, preliminary results suggest that cyclical forces more than 1.5 times body weight are imposed on the leg long bones which may help to reduce the risk of fragility fractures. We have demonstrated the feasibility of FES rowing on land and water using adapted rowing technology that includes; a fixed stretcher indoor ergometer (adapted Concept 2, Model E), a floating stretcher indoor ergometer (adapted Concept 2 Dynamic), a turbine powered water rowing tank, a custom hydraulic sculling simulator and a single scull (adapted Alden 16). This has involved volunteers with paraplegia and tetraplegia with SCI ranging from C4 to T12 AIS A using at least 4-channels of surface electrical stimulation. FES rowers, with SCI, have competed alongside non-SCI rowers over the Olympic distance of 2000 m at the British Indoor Rowing Championships in 2004, 2005, and 2006

  19. Effects of low-voltage electrical stimulation and rapid chilling on meat quality characteristics of Chinese Yellow crossbred bulls.

    Science.gov (United States)

    Li, C B; Chen, Y J; Xu, X L; Huang, M; Hu, T J; Zhou, G H

    2010-04-22

    In this study, the effects of low-voltage electrical stimulation (LVES) and rapid chilling (RC) treatments on the quality characteristics of beef carcasses were evaluated, including the rate of pH and temperature decline, evaporative loss of carcasses, purge loss, cooking loss, and shear force values of m. longissimus steaks. Each carcass of 28 Chinese Yellow crossbred (SimmentalxYanbian) bulls was subjected to one of the four treatments, i.e., electrical stimulation and conventional chilling (ES/NR), electrical stimulation and rapid chilling (ES/RC), no electrical stimulation and rapid chilling (NE/RC), or no electrical stimulation and conventional chilling (NE/NR). Carcass pH and temperature were measured at 1, 3, 5, 7, 9, 11, and 24h post-mortem. After that, a 2.5-cm-thick m. longissimus steak was taken from the right side of each carcass and used for analyses of purge loss, cooking loss and Warner-Bratzler shear force (WBSF). The results showed that LVES accelerated the rate of carcass pH decline (Pchilling increased the rate of carcass temperature decline (P0.05). Mean purge losses for m. longissimus steaks from rapidly chilled carcasses were lower (Pchilled carcasses. Electrical stimulation had no impact on m. longissimus steak purge losses (P>0.05). Rapid chilling significantly decreased (Pchilled carcasses, but had no effect under the procedure of pre-rigor rapid chilling (P>0.05). The lowest mean shear force value was found for the ES/NR-treated m. longissimus steaks, whilst the highest one for the NE/RC-treated carcasses (Pchilling. Copyright © 2005. Published by Elsevier Ltd.

  20. Electric Field Model of Transcranial Electric Stimulation in Nonhuman Primates: Correspondence to Individual Motor Threshold.

    Science.gov (United States)

    Lee, Won Hee; Lisanby, Sarah H; Laine, Andrew F; Peterchev, Angel V

    2015-09-01

    To develop a pipeline for realistic head models of nonhuman primates (NHPs) for simulations of noninvasive brain stimulation, and use these models together with empirical threshold measurements to demonstrate that the models capture individual anatomical variability. Based on structural MRI data, we created models of the electric field (E-field) induced by right unilateral (RUL) electroconvulsive therapy (ECT) in four rhesus macaques. Individual motor threshold (MT) was measured with transcranial electric stimulation (TES) administered through the RUL electrodes in the same subjects. The interindividual anatomical differences resulted in 57% variation in median E-field strength in the brain at fixed stimulus current amplitude. Individualization of the stimulus current by MT reduced the E-field variation in the target motor area by 27%. There was significant correlation between the measured MT and the ratio of simulated electrode current and E-field strength (r(2) = 0.95, p = 0.026). Exploratory analysis revealed significant correlations of this ratio with anatomical parameters including of the superior electrode-to-cortex distance, vertex-to-cortex distance, and brain volume (r(2) > 0.96, p field models appropriately capture individual anatomical variability relevant to the dosing of TES/ECT. These findings are exploratory due to the small number of subjects. This study can contribute insight in NHP studies of ECT and other brain stimulation interventions, help link the results to clinical studies, and ultimately lead to more rational brain stimulation dosing paradigms.

  1. Iterative learning control for electrical stimulation and stroke rehabilitation

    CERN Document Server

    Freeman, Chris T; Burridge, Jane H; Hughes, Ann-Marie; Meadmore, Katie L

    2015-01-01

    Iterative learning control (ILC) has its origins in the control of processes that perform a task repetitively with a view to improving accuracy from trial to trial by using information from previous executions of the task. This brief shows how a classic application of this technique – trajectory following in robots – can be extended to neurological rehabilitation after stroke. Regaining upper limb movement is an important step in a return to independence after stroke, but the prognosis for such recovery has remained poor. Rehabilitation robotics provides the opportunity for repetitive task-oriented movement practice reflecting the importance of such intense practice demonstrated by conventional therapeutic research and motor learning theory. Until now this technique has not allowed feedback from one practice repetition to influence the next, also implicated as an important factor in therapy. The authors demonstrate how ILC can be used to adjust external functional electrical stimulation of patients’ mus...

  2. Pharyngeal Electrical Stimulation for Treatment of Dysphagia in Subacute Stroke

    DEFF Research Database (Denmark)

    Bath, Philip M W; Scutt, Polly; Love, Jo

    2016-01-01

    BACKGROUND AND PURPOSE: Dysphagia is common after stroke, associated with increased death and dependency, and treatment options are limited. Pharyngeal electric stimulation (PES) is a novel treatment for poststroke dysphagia that has shown promise in 3 pilot randomized controlled trials. METHODS......: We randomly assigned 162 patients with a recent ischemic or hemorrhagic stroke and dysphagia, defined as a penetration aspiration score (PAS) of ≥3 on video fluoroscopy, to PES or sham treatment given on 3 consecutive days. The primary outcome was swallowing safety, assessed using the PAS, at 2 weeks....... Secondary outcomes included dysphagia severity, function, quality of life, and serious adverse events at 6 and 12 weeks. RESULTS: In randomized patients, the mean age was 74 years, male 58%, ischemic stroke 89%, and PAS 4.8. The mean treatment current was 14.8 (7.9) mA and duration 9.9 (1.2) minutes per...

  3. Role of Functional Electrical Stimulation in Tetraplegia Hand Surgery.

    Science.gov (United States)

    Bersch, Ines; Fridén, Jan

    2016-06-01

    The use of functional electrical stimulation (FES) to improve upper limb function is an established method in the rehabilitation of persons with tetraplegia after spinal cord injury. Surgical reconstruction is another well-established yet underused technique to improve the performance of the upper extremities. Hand surgery plays an essential role in restoring hand function, mobility, and quality of life in the tetraplegic population. The knowledge about the effects of FES on a structural and functional level is fundamental for understanding how and when FES can be used best to support the effect of hand surgery, both pre- and postoperatively. In this article we discuss principles of FES and how FES improves functional outcome after surgical reconstruction. The reported results are based on preliminary clinical observations. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  4. Deqi Sensations of Transcutaneous Electrical Nerve Stimulation on Auricular Points

    Directory of Open Access Journals (Sweden)

    Xiaoling Wang

    2013-01-01

    Full Text Available Deqi sensation, a psychophysical response characterized by a spectrum of different needling sensations, is essential for Chinese acupuncture clinical efficacy. Previous research works have investigated the component of Deqi response upon acupuncture on acupoints on the trunk and limbs. However, the characteristics of Deqi sensations of transcutaneous electrical nerve stimulation (TENS on auricular points are seldom reported. In this study, we investigated the individual components of Deqi during TENS on auricular concha area and the superior scapha using quantitative measurements in the healthy subjects and depression patients. The most striking characteristics of Deqi sensations upon TENS on auricular points were tingling, numbness, and fullness. The frequencies of pressure, warmness, heaviness, and soreness were relatively lower. The dull pain and coolness are rare. The characteristics of Deqi were similar for the TENS on concha and on the superior scapha.

  5. Functional electrical stimulation improves brain perfusion in cranial trauma patients

    Directory of Open Access Journals (Sweden)

    Bárbara Juarez Amorim

    2011-08-01

    Full Text Available OBJECTIVE: Demonstrate brain perfusion changes due to neuronal activation after functional electrical stimulation (FES. METHOD: It was studied 14 patients with hemiplegia who were submitted to a program with FES during fourteen weeks. Brain perfusion SPECT was performed before and after FES therapy. These patients were further separated into 2 groups according to the hemiplegia cause: cranial trauma and major vascular insults. All SPECT images were analyzed using SPM. RESULTS: There was a significant statistical difference between the two groups related to patient's ages and extent of hypoperfusion in the SPECT. Patients with cranial trauma had a reduction in the hypoperfused area and patients with major vascular insult had an increase in the hypoperfused area after FES therapy. CONCLUSION: FES therapy can result in brain perfusion improvement in patients with brain lesions due to cranial trauma but probably not in patients with major vascular insults with large infarct area.

  6. Tinnitus Treatment with Precise and Optimal Electric Stimulation: Opportunities and Challenges

    OpenAIRE

    Zeng, FG; Djalilian, H; Lin, H.

    2015-01-01

    © 2015 Wolters Kluwer Health, Inc. All rights reserved. PURPOSE OF REVIEW: Electric stimulation is a potent means of neuromodulation that has been used to restore hearing and minimize tremor, but its application on tinnitus symptoms has been limited. We examine recent evidence to identify the knowledge gaps in the use of electric stimulation for tinnitus treatment. RECENT FINDINGS: Recent studies using electric stimulation to suppress tinnitus in humans are categorized according to their poin...

  7. Biophysical Model of Cortical Network Activity and the Influence of Electrical Stimulation

    Science.gov (United States)

    2015-11-13

    SECURITY CLASSIFICATION OF: We examined the effects of subdural electrical stimulation on a high-density network consisting of several populations of...multicompartment cell types. The results can be summarized as follows: 1) Electrical stimulation mainly affects and activates axon initial and the most...of Electrical Stimulation . The views, opinions and/or findings contained in this report are those of the author(s) and should not contrued as an

  8. A Systematic Review of Electric-Acoustic Stimulation: Device Fitting Ranges, Outcomes, and Clinical Fitting Practices

    OpenAIRE

    Incerti, Paola V.; Ching, Teresa Y. C.; Cowan, Robert

    2013-01-01

    Cochlear implant systems that combine electric and acoustic stimulation in the same ear are now commercially available and the number of patients using these devices is steadily increasing. In particular, electric-acoustic stimulation is an option for patients with severe, high frequency sensorineural hearing impairment. There have been a range of approaches to combining electric stimulation and acoustic hearing in the same ear. To develop a better understanding of fitting practices for devic...

  9. Subthalamic nucleus electrical stimulation modulates calcium activity of nigral astrocytes.

    Directory of Open Access Journals (Sweden)

    Elodie Barat

    Full Text Available BACKGROUND: The substantia nigra pars reticulata (SNr is a major output nucleus of the basal ganglia, delivering inhibitory efferents to the relay nuclei of the thalamus. Pathological hyperactivity of SNr neurons is known to be responsible for some motor disorders e.g. in Parkinson's disease. One way to restore this pathological activity is to electrically stimulate one of the SNr input, the excitatory subthalamic nucleus (STN, which has emerged as an effective treatment for parkinsonian patients. The neuronal network and signal processing of the basal ganglia are well known but, paradoxically, the role of astrocytes in the regulation of SNr activity has never been studied. PRINCIPAL FINDINGS: In this work, we developed a rat brain slice model to study the influence of spontaneous and induced excitability of afferent nuclei on SNr astrocytes calcium activity. Astrocytes represent the main cellular population in the SNr and display spontaneous calcium activities in basal conditions. Half of this activity is autonomous (i.e. independent of synaptic activity while the other half is dependent on spontaneous glutamate and GABA release, probably controlled by the pace-maker activity of the pallido-nigral and subthalamo-nigral loops. Modification of the activity of the loops by STN electrical stimulation disrupted this astrocytic calcium excitability through an increase of glutamate and GABA releases. Astrocytic AMPA, mGlu and GABA(A receptors were involved in this effect. SIGNIFICANCE: Astrocytes are now viewed as active components of neural networks but their role depends on the brain structure concerned. In the SNr, evoked activity prevails and autonomous calcium activity is lower than in the cortex or hippocampus. Our data therefore reflect a specific role of SNr astrocytes in sensing the STN-GPe-SNr loops activity and suggest that SNr astrocytes could potentially feedback on SNr neuronal activity. These findings have major implications given the

  10. Chronic stress decreases cerebrovascular responses during rat hindlimb electrical stimulation

    Directory of Open Access Journals (Sweden)

    Sohee eLee

    2015-12-01

    Full Text Available Repeated stress is one of the major risk factors for cerebrovascular disease, including stroke and vascular dementia. However, the functional alterations in the cerebral hemodynamic response induced by chronic stress have not been clarified. Here, we investigated the in vivo cerebral hemodynamic changes and accompanying cellular and molecular changes in chronically stressed rats. After three weeks of restraint stress, the elicitation of stress was verified by behavioral despair in the forced swimming test and by physical indicators of stress. The evoked changes in the cerebral blood volume and pial artery responses following hindpaw electrical stimulation were measured using optical intrinsic signal imaging. We observed that, compared to the control group, animals under chronic restraint stress exhibited a decreased hemodynamic response, with a smaller pial arterial dilation in the somatosensory cortex during hindpaw electrical stimulation. The effect of chronic restraint stress on vasomodulator enzymes, including neuronal nitric oxide synthase (nNOS and heme oxygenase-2 (HO-2, was assessed in the somatosensory cortex. Chronic restraint stress downregulated nNOS and HO-2 compared to the control group. In addition, we examined the subtypes of cells that can explain the environmental changes due to the decreased vasomodulators. The expression of parvalbumin in GABAergic interneurons and glutamate receptor-1 in neurons were decreased, whereas the microglial activation was increased. Our results suggest that the chronic stress-induced alterations in cerebral vascular function and the modulations of the cellular expression in the neuro-vasomodulatory system may be crucial contributing factors in the development of various vascular-induced conditions in the brain.

  11. Using noninvasive brain stimulation to accelerate learning and enhance human performance.

    Science.gov (United States)

    Parasuraman, Raja; McKinley, Richard A

    2014-08-01

    The authors evaluate the effectiveness of noninvasive brain stimulation, in particular, transcranial direct current stimulation (tDCS), for accelerating learning and enhancing human performance on complex tasks. Developing expertise in complex tasks typically requires extended training and practice. Neuroergonomics research has suggested new methods that can accelerate learning and boost human performance. TDCS is one such method. It involves the application of a weak DC current to the scalp and has the potential to modulate brain networks underlying the performance of a perceptual, cognitive, or motor task. Examples of tDCS studies of declarative and procedural learning are discussed. This mini-review focuses on studies employing complex simulations representative of surveillance and security operations, intelligence analysis, and procedural learning in complex monitoring. The evidence supports the view that tDCS can accelerate learning and enhance performance in a range of complex cognitive tasks. Initial findings also suggest that such benefits can be retained over time, but additional research is needed on training schedules and transfer of training. Noninvasive brain stimulation can accelerate skill acquisition in complex tasks and may provide an alternative or addition to other training methods.

  12. Transcutaneous electrical spinal-cord stimulation in humans

    Science.gov (United States)

    Gerasimenko, Yury; Gorodnichev, Ruslan; Moshonkina, Tatiana; Sayenko, Dimitry; Gad, Parag; Edgerton, V. Reggie

    2016-01-01

    Locomotor behavior is controlled by specific neural circuits called central pattern generators primarily located at the lumbosacral spinal cord. These locomotor-related neuronal circuits have a high level of automaticity; that is, they can produce a “stepping” movement pattern also seen on electromyography (EMG) in the absence of supraspinal and/or peripheral afferent inputs. These circuits can be modulated by epidural spinal-cord stimulation and/or pharmacological intervention. Such interventions have been used to neuromodulate the neuronal circuits in patients with motor-complete spinal-cord injury (SCI) to facilitate postural and locomotor adjustments and to regain voluntary motor control. Here, we describe a novel non-invasive stimulation strategy of painless transcutaneous electrical enabling motor control (pcEmc) to neuromodulate the physiological state of the spinal cord. The technique can facilitate a stepping performance in non-injured subjects with legs placed in a gravity-neutral position. The stepping movements were induced more effectively with multi-site than single-site spinal-cord stimulation. From these results, a multielectrode surface array technology was developed. Our preliminary data indicate that use of the multielectrode surface array can fine-tune the control of the locomotor behavior. As well, the pcEmc strategy combined with exoskeleton technology is effective for improving motor function in paralyzed patients with SCI. The potential impact of using pcEmc to neuromodulate the spinal circuitry has significant implications for furthering our understanding of the mechanisms controlling locomotion and for rehabilitating sensorimotor function even after severe SCI. PMID:26205686

  13. Transcutaneous electrical spinal-cord stimulation in humans.

    Science.gov (United States)

    Gerasimenko, Yury; Gorodnichev, Ruslan; Moshonkina, Tatiana; Sayenko, Dimitry; Gad, Parag; Reggie Edgerton, V

    2015-09-01

    Locomotor behavior is controlled by specific neural circuits called central pattern generators primarily located at the lumbosacral spinal cord. These locomotor-related neuronal circuits have a high level of automaticity; that is, they can produce a "stepping" movement pattern also seen on electromyography (EMG) in the absence of supraspinal and/or peripheral afferent inputs. These circuits can be modulated by epidural spinal-cord stimulation and/or pharmacological intervention. Such interventions have been used to neuromodulate the neuronal circuits in patients with motor-complete spinal-cord injury (SCI) to facilitate postural and locomotor adjustments and to regain voluntary motor control. Here, we describe a novel non-invasive stimulation strategy of painless transcutaneous electrical enabling motor control (pcEmc) to neuromodulate the physiological state of the spinal cord. The technique can facilitate a stepping performance in non-injured subjects with legs placed in a gravity-neutral position. The stepping movements were induced more effectively with multi-site than single-site spinal-cord stimulation. From these results, a multielectrode surface array technology was developed. Our preliminary data indicate that use of the multielectrode surface array can fine-tune the control of the locomotor behavior. As well, the pcEmc strategy combined with exoskeleton technology is effective for improving motor function in paralyzed patients with SCI. The potential impact of using pcEmc to neuromodulate the spinal circuitry has significant implications for furthering our understanding of the mechanisms controlling locomotion and for rehabilitating sensorimotor function even after severe SCI. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  14. The value of electrical stimulation as an exercise training modality

    Science.gov (United States)

    Currier, Dean P.; Ray, J. Michael; Nyland, John; Noteboom, Tim

    1994-01-01

    Voluntary exercise is the traditional way of improving performance of the human body in both the healthy and unhealthy states. Physiological responses to voluntary exercise are well documented. It benefits the functions of bone, joints, connective tissue, and muscle. In recent years, research has shown that neuromuscular electrical stimulation (NMES) simulates voluntary exercise in many ways. Generically, NMES can perform three major functions: suppression of pain, improve healing of soft tissues, and produce muscle contractions. Low frequency NMES may gate or disrupt the sensory input to the central nervous system which results in masking or control of pain. At the same time NMES may contribute to the activation of endorphins, serotonin, vasoactive intestinal polypeptides, and ACTH which control pain and may even cause improved athletic performances. Soft tissue conditions such as wounds and inflammations have responded very favorably to NMES. NMES of various amplitudes can induce muscle contractions ranging from weak to intense levels. NMES seems to have made its greatest gains in rehabilitation where directed muscle contractions may improve joint ranges of motion correct joint contractures that result from shortening muscles; control abnormal movements through facilitating recruitment or excitation into the alpha motoneuron in orthopedically, neurologically, or healthy subjects with intense sensory, kinesthetic, and proprioceptive information; provide a conservative approach to management of spasticity in neurological patients; by stimulation of the antagonist muscle to a spastic muscle stimulation of the agonist muscle, and sensory habituation; serve as an orthotic substitute to conventional bracing used with stroke patients in lieu of dorsiflexor muscles in preventing step page gait and for shoulder muscles to maintain glenohumeral alignment to prevent subluxation; and of course NMES is used in maintaining or improving the performance or torque producing

  15. Evaluation of the effects of electrical stimulation on cartilage repair in adult male rats.

    Science.gov (United States)

    Zuzzi, Denise Cristina; Ciccone, Carla de Campos; Neves, Lia Mara Grosso; Mendonça, Josué Sampaio; Joazeiro, Paulo Pinto; Esquisatto, Marcelo Augusto Marretto

    2013-08-01

    This study describes the organization of mature hyaline xiphoid cartilage during repair in animals submitted to electrical current stimulation. Twenty male Wistar rats, 90 days old, were divided into a control group (CG) and a treated group (TG). A cylindrical full-thickness cartilage defects were created with a 3-mm punch in anesthetized animals. After 24h, TG received daily applications of a continuous electrical current (1Hz/20μA) for 5min. The animals were sacrificed after 7, 21 and 35 days for structural analysis. In CG, the repair tissue presented fibrous characteristics, with fibroblastic cells being infiltrated and permeated by blood vessels. Basophilic foci of cartilage tissue were observed on day 35. In TG, the repair tissue also presented fibrous characteristics, but a larger number of thick collagen fibers were seen on day 21. A large number of cartilaginous nests were observed on day 35. Cell numbers were significantly higher in TG. Calcification points were detected in TG on day 35. There was no difference in elastic fibers between groups. Ultrastructural analysis revealed the presence of chondrocyte-like cells in CG at all time points, but only on days 21 and 35 in TG. The amount of cuprolinic blue-stained proteoglycans was higher in TG on day 35. Microcurrent stimulation accelerates the repair process in non-articular hyaline cartilage. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  16. Decreased central fatigue in multiple sclerosis patients after 8 weeks of surface functional electrical stimulation

    National Research Council Canada - National Science Library

    Chang, Ya-Ju; Hsu, Miao-Ju; Chen, Shin-Man; Lin, Cheng-Hsiang; Wong, Alice M K

    2011-01-01

    .... Surface functional electrical stimulation (FES), which can challenge the peripheral neuromuscular system without overloading the central nervous system, is a relatively safe therapeutic strategy...

  17. Maximizing muscle force via low-cadence functional electrical stimulation cycling

    National Research Council Canada - National Science Library

    Fornusek, Ché; Davis, Glen M

    2004-01-01

    This study investigated the effect of pedal cadence upon torque production, power output and muscle fatigue rates during functional electrical stimulation evoked cycling in spinal cord injured individuals...

  18. Effect of transcutaneous electrical nerve stimulation induced parotid stimulation on salivary flow

    Directory of Open Access Journals (Sweden)

    Sreenivasulu Pattipati

    2013-01-01

    Full Text Available Aims and Objectives: The main objective of this study was to evaluate the duration of stimulation over the parotid salivary flow following the use of transcutaneous electric nerve stimulation (TENS in different age groups. Materials and Methods: The study was carried out in three different age groups. Under group A individuals from 21 to 35 years of age, group B 36-50 years and group C above 51 years were considered. In each group 30 subjects were taken of whom 15 were males and 15 were females. The placement of pads was approximated bilaterally over the parotid glands. The working parameters of TENS unit were fixed at 50 Hz and the unit was in normal mode. Results: Subjects belonging to group B were showing statistically significant increases in the duration of stimulated parotid salivary flow following the use of TENS. Conclusion: TENS can be considered as a non-pharmacological alternative to improve salivation for longer period in xerostomia patients.

  19. Effects of electrical stimulation on meat quality of lamb and goat meat.

    Science.gov (United States)

    Cetin, Omer; Bingol, Enver Baris; Colak, Hilal; Hampikyan, Hamparsun

    2012-01-01

    Effect of various voltage of electrical stimulation (ES) on meat quality of lamb and goat was investigated by using a total of 36 animals at 3-5 years old. Constant 50 Hz frequency and 50, 100, and 250 V, 90 sec of ES were administered to 1/2 carcasses and were examined according their textural, physicochemical, and sensorial characteristics. ES decreased the pH values of lamb and goat meat, and accelerated the rigor mortis (P meat, and tenderness was improved depending on voltage range used (P L*a*b*) values of lamb and goat meat compared with the control groups (P meat quality of lamb and goat, in contrast to undesirable consumer preferences.

  20. Investigation of the accelerating electric fields in laser-induced ion beams

    Science.gov (United States)

    Delle Side, D.; Giuffreda, E.; Nassisi, V.

    2017-09-01

    The Front Surface Acceleration (FSA) obtained in Laser Ion Source (LIS) systems is one of the most interesting methods to produce accelerated protons and ions. We implemented a LIS to study the electric field responsible for the ion acceleration mechanisms. A high impedance resistive probe was used to map the electric potential inside the chamber, near the target. We detected the time resolved profiles of the electric potential moving the probe from 4.7 cm to 6.2 cm with respect to the main target axis. The corresponding electric field depends on the distance x as 1 /xα with α ∼ 1.8 . We suggest that the electric field strength stems from the contribution of an electrostatic and an induced field.

  1. Tenderness enhancement of beef from Bos indicus and Bos taurus cattle following electrical stimulation.

    Science.gov (United States)

    Gursansky, B; O'Halloran, J M; Egan, A; Devine, C E

    2010-11-01

    High voltage electrical stimulation (1130 V peak, 14.28 bidirectional half sinusoidal pulses/s) or low voltage stimulation (45 V peak, 36 alternating square wave pulses/s) was used on cattle: (1) low voltage stimulation applied for 10 or 40 s with fast and slow chilling or high voltage stimulation for 60 s with normal chilling, applied to 100% Bos taurus cattle, (2) low voltage stimulation (40 s) and high voltage stimulation (60 s) with normal chilling applied to mixed Bos indicus and B.taurus cattle, (3) high voltage stimulation (54 s) with normal chilling applied to B. taurus and B. indicus cattle of 0-100% B. indicus composition, and (4) high voltage stimulation (60 s) applied to 100% B. taurus and 100% B. indicus cattle. All stimulation parameters enhanced the tenderness of steaks from M. longissimus thoracis et lumborum (LTL) aged at 1°C up to 28 days compared with non stimulated LTL. Short low voltage stimulation of 10s was marginally more effective than no stimulation and longer durations of 40s were very effective and high voltage stimulation was most effective. The shear force values for non stimulated B. indicus LTL are much greater than for B. taurus, but following high voltage stimulation LTL of B. indicus were similar to B. taurus and all had lower shear force values than from non stimulated carcasses. Thus adequate electrical stimulation removes any toughness of LTL related to B. indicus genetic composition. Copyright © 2010. Published by Elsevier Ltd.

  2. Blunted Peripheral and Central Responses to Gastric Mechanical and Electrical Stimulations in Diet-induced Obese Rats.

    Science.gov (United States)

    Zhang, Jing; Sha, Weihong; Zhu, Hongbing; Chen, Jiande D Z

    2013-10-01

    The increase in the prevalence of obesity is attributed to increased food intake and decreased physical activity in addition to genetic factors. Altered gut functions have been reported in obese subjects, whereas, little is known on the possible alterations in brain-gut interactions in obesity. The aim of the study was to explore possible alterations in gastric myoelectrical activity, gastric emptying, autonomic functions and central neuronal responses to gastric stimulations in diet-induced obese rats. Gastric myoelectrical activity, gastric emptying and heart rate variability were recorded in lean and obese rats; extracellular neuronal activity in the ventromedial hypothalamus and its responses to gastric stimulations were also assessed. (1) Gastric emptying was significantly accelerated but gastric myoelectrical activity was not altered in obese rats; (2) the normal autonomic responses to feeding were absent in obese rats, suggesting an impairment of postprandial modulation of autonomic functions; and (3) central neuronal responses to gastric stimulations (both balloon distention and electrical stimulation) were blunted in obese rats, suggesting impairment in the brain-gut interaction. In diet-induced obese rats, gastric emptying is accelerated, postprandial modulations of autonomic functions is altered and central neuronal responses to gastric stimulations are attenuated. These alterations in peripheral, autonomic and brain-gut interactions may help better understand pathogenesis of obesity and develop novel therapeutic approaches for obesity.

  3. Electrical field stimulation promotes anastomotic healing in poorly perfused rat colon.

    LENUS (Irish Health Repository)

    Kennelly, Rory

    2011-03-01

    Hypoperfusion of the bowel is a risk factor for anastomotic failure. Electrical field stimulation has been shown to improve repair in ischemic tissue, but its influence in hypoperfused colon has not been investigated. The hypothesis of this experimental animal study was that electrical field stimulation improves anastomotic healing in ischemic bowel.

  4. Spasticity reduction using electrical stimulation in the lower limb of spinal cord injury patients

    NARCIS (Netherlands)

    van der Salm, Arjan

    2005-01-01

    The goal of this thesis was to investigate the influence of electrical stimulation on spasticity of leg muscles in spinal cord injury patients and its impact on gait. Both, the carry-over effect and the instant effect of electrical stimulation during gait were investigated.

  5. Electrical Stimulation Promotes Cardiac Differentiation of Human Induced Pluripotent Stem Cells

    Science.gov (United States)

    Hernández, Damián; Millard, Rodney; Sivakumaran, Priyadharshini; Wong, Raymond C. B.; Crombie, Duncan E.; Hewitt, Alex W.; Liang, Helena; Hung, Sandy S. C.; Pébay, Alice; Shepherd, Robert K.; Dusting, Gregory J.; Lim, Shiang Y.

    2016-01-01

    Background. Human induced pluripotent stem cells (iPSCs) are an attractive source of cardiomyocytes for cardiac repair and regeneration. In this study, we aim to determine whether acute electrical stimulation of human iPSCs can promote their differentiation to cardiomyocytes. Methods. Human iPSCs were differentiated to cardiac cells by forming embryoid bodies (EBs) for 5 days. EBs were then subjected to brief electrical stimulation and plated down for 14 days. Results. In iPS(Foreskin)-2 cell line, brief electrical stimulation at 65 mV/mm or 200 mV/mm for 5 min significantly increased the percentage of beating EBs present by day 14 after plating. Acute electrical stimulation also significantly increased the cardiac gene expression of ACTC1, TNNT2, MYH7, and MYL7. However, the cardiogenic effect of electrical stimulation was not reproducible in another iPS cell line, CERA007c6. Beating EBs from control and electrically stimulated groups expressed various cardiac-specific transcription factors and contractile muscle markers. Beating EBs were also shown to cycle calcium and were responsive to the chronotropic agents, isoproterenol and carbamylcholine, in a concentration-dependent manner. Conclusions. Our results demonstrate that brief electrical stimulation can promote cardiac differentiation of human iPS cells. The cardiogenic effect of brief electrical stimulation is dependent on the cell line used. PMID:26788064

  6. Electrical Stimulation Promotes Cardiac Differentiation of Human Induced Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Damián Hernández

    2016-01-01

    Full Text Available Background. Human induced pluripotent stem cells (iPSCs are an attractive source of cardiomyocytes for cardiac repair and regeneration. In this study, we aim to determine whether acute electrical stimulation of human iPSCs can promote their differentiation to cardiomyocytes. Methods. Human iPSCs were differentiated to cardiac cells by forming embryoid bodies (EBs for 5 days. EBs were then subjected to brief electrical stimulation and plated down for 14 days. Results. In iPS(Foreskin-2 cell line, brief electrical stimulation at 65 mV/mm or 200 mV/mm for 5 min significantly increased the percentage of beating EBs present by day 14 after plating. Acute electrical stimulation also significantly increased the cardiac gene expression of ACTC1, TNNT2, MYH7, and MYL7. However, the cardiogenic effect of electrical stimulation was not reproducible in another iPS cell line, CERA007c6. Beating EBs from control and electrically stimulated groups expressed various cardiac-specific transcription factors and contractile muscle markers. Beating EBs were also shown to cycle calcium and were responsive to the chronotropic agents, isoproterenol and carbamylcholine, in a concentration-dependent manner. Conclusions. Our results demonstrate that brief electrical stimulation can promote cardiac differentiation of human iPS cells. The cardiogenic effect of brief electrical stimulation is dependent on the cell line used.

  7. 9 CFR 307.7 - Safety requirements for electrical stimulating (EST) equipment.

    Science.gov (United States)

    2010-01-01

    ... is surrounded by physical barriers, the enclosure shall be either electrically grounded or it shall... manual stimulation or before the carcass chain is started in an automatic system. (c) Operation— (1... personnel, the electricity supplied to the stimulating surfaces shall be locked-off when cleaning...

  8. Tinnitus treatment with precise and optimal electric stimulation: opportunities and challenges.

    Science.gov (United States)

    Zeng, Fan-Gang; Djalilian, Hamid; Lin, Harrison

    2015-10-01

    Electric stimulation is a potent means of neuromodulation that has been used to restore hearing and minimize tremor, but its application on tinnitus symptoms has been limited. We examine recent evidence to identify the knowledge gaps in the use of electric stimulation for tinnitus treatment. Recent studies using electric stimulation to suppress tinnitus in humans are categorized according to their points of attacks. First, noninvasive, direct current stimulation uses an active electrode in the ear canal, tympanic membrane, or temporal scalp. Second, inner ear stimulation uses charge-balanced biphasic stimulation by placing an active electrode on the promontory or round window, or a cochlear implant array in the cochlea. Third, intraneural implants can provide targeted stimulation of specific sites along the auditory pathway. Although these studies demonstrated some success in tinnitus suppression, none established a link between tinnitus suppression efficacy and tinnitus-generating mechanisms. Electric stimulation provides a unique opportunity to suppress tinnitus. Challenges include matching electric stimulation sites and patterns to tinnitus locus and type, meeting the oftentimes-contradictory demands between tinnitus suppression and other indications, such as speech understanding, and justifying the costs and risks of electric stimulation for tinnitus symptoms.

  9. Determination of the needed power of an electric motor on the basis of acceleration time of the electric car

    Science.gov (United States)

    Sapundzhiev, M.; Evtimov, I.; Ivanov, R.

    2017-10-01

    The paper presents an upgraded methodology for determination of the electric motor power considering the time for acceleration. The influence of the speed factor of electric motor on the value of needed power at same acceleration time is studied. Some calculations on the basis of real vehicle were made. The numeric and graphical results are given. They show a decrease of needed power with the increase of the speed factor of motor, because the high speed factor allows the use of a larger range of the characteristic with the maximum power of the motor. An experimental verification of methodology was done.

  10. Videoradiography at submental electrical stimulation during apnea in obstructive sleep apnea syndrome; A case report

    Energy Technology Data Exchange (ETDEWEB)

    Hillarp, B.; Rosen, I.; Wickstroem, O. (Malmoe Allmaenna Sjukhus (Sweden). Dept. of Diagnostic Radiology Malmoe Allmaenna Sjukhus (Sweden). Dept. of Clinical Neurophysiology)

    1991-05-01

    Percutaneous submental electrical stimulation during sleep may be a new therapeutic method for patients with obstructive sleep apnea syndrome (OSAS). Electrical stimulation to the submental region during obstructive apnea is reported to break the apnea without arousal and to diminish apneic index, time spent in apnea, and oxygen desaturation. The mode of breaking the apnea by electrical stimulation has not yet been shown. However, genioglossus is supposed to be the muscle responsible for breaking the apnea by forward movement of the tongue. To visualize the effect of submental electrical stimulation, one patient with severe OSAS has been examined with videoradiography. Submental electrical stimulation evoked an immediate complex muscle activity in the tongue, palate, and hyoid bone. This was followed by a forward movement of the tongue which consistently broke obstructive apnea without apparent arousal. Time spent in apnea was diminished but intervals between apnea were not affected. (orig.).

  11. The enhancement of neuronal cells wound healing with non-contact electric field stimulation by graphene electrodes

    Science.gov (United States)

    Lee, Sohee; Heo, Chaejeong; Lee, Si Young; Lee, Young Hee; Suh, Minah

    2013-05-01

    Electrical stimulation affects cellular behaviors including division, migration and wound healing [1-3]. Cellular injury often occurs due to the imbalance of the endogenous electric field [3]. In order to recover from the injury, wound healing process requires various cellular changes such as regeneration, migration, and the enhancement of cytoskeletal proteins and growth factors. In previous reports, a weak non-contact electric field stimulation (nEFS) accelerates the cell migration as well as cell-to-cell coupling between neuronal cell junction which are accompanied by increasing of cytoskeletal proteins [4, 5]. In this paper, we further investigated the wound healing effect of the nEFS in the neuronal cells (SHSY5Y cells) with live cell optical imaging. Cells were cultured over the optically transparent graphenen EF stimulator. Cellular behavioral changes upon nEFS were recorded with live optical imaging during stimulation of 120 minutes. The ability of wound healing was significantly enhanced with the nEFS. In particular, nEFS significantly shorten the duration of wound healing process. Moreover, after treating cells with cytochalasin D, a block polymerization of the actin filaments, the nEFS significantly enhanced wound healing process of cytochalasin D treated neural cells as compared to the control neural cells. This study suggests that nEFS may provide an effective way to control neural cells repairing process from cellular injury. Further mechanism study about the effect of nEFS on the wound healing may shed new light on cellular behavior.

  12. Therapeutic Angiogenesis via Solar Cell-Facilitated Electrical Stimulation.

    Science.gov (United States)

    Jeong, Gun-Jae; Oh, Jin Young; Kim, Yeon-Ju; Bhang, Suk Ho; Jang, Hyeon-Ki; Han, Jin; Yoon, Jeong-Kee; Kwon, Sang-Mo; Lee, Tae Il; Kim, Byung-Soo

    2017-11-08

    Cell therapy has been suggested as a treatment modality for ischemic diseases, but the poor survival and engraftment of implanted cells limit its therapeutic efficacy. To overcome such limitation, we used electrical stimulation (ES) derived from a wearable solar cell for inducing angiogenesis in ischemic tissue. ES enhanced the secretion of angiogenic growth factors and the migration of mesenchymal stem cells (MSCs), myoblasts, endothelial progenitor cells, and endothelial cells in vitro. In a mouse ischemic hindlimb model, ES generated by a solar cell and applied to the ischemic region promoted migration of MSCs toward the ischemic site and upregulated expression of angiogenic paracrine factors (vascular endothelial, basic fibroblast, and hepatocyte growth factors; and stromal cell-derived factor-1α). Importantly, solar cell-generated ES promoted the formation of capillaries and arterioles at the ischemic region, attenuated muscle necrosis and fibrosis, and eventually prevented loss of the ischemic limb. Solar cell ES therapy showed higher angiogenic efficacy than conventional MSC therapy. This study shows the feasibility of using solar cell ES as a novel treatment for therapeutic angiogenesis.

  13. Percutaneous electrical stimulation in strength training: an update.

    Science.gov (United States)

    Requena Sánchez, Bernardo; Padial Puche, Paulino; González-Badillo, Juan José

    2005-05-01

    Numerous studies have used percutaneous electrical stimulation (PES) in the context of training programs to develop strength and physical performance in healthy populations (sedentary or trained). Significant increases in muscle and fiber cross-sectional area, isokinetic peak torque, maximal isometric and dynamic strength, and motor performance skills have been found after PES training. These strength gains are explained on the basis of the characteristics of PES motor units (MUs) recruitment: (a) a continuous and exhausting contractile activity in the same pool of MUs during the entire exercise period, (b) a supramaximal temporal recruitment imposed by the high frequency chosen (up to 40 Hz), and (c) a synchronous recruitment of neighboring fibers. The PES training method is complementary to voluntary training, mainly because the application of PES causes an unconventional spatial recruitment of MUs that, depending on the muscular topography, may entail the preferential recruitment of the fast-twitch MUs. In addition, the method does not specifically develop elasticity in skeletal muscle, and it must be accompanied by a technical workout.

  14. Functional electrical stimulation in spinal cord injury respiratory care.

    Science.gov (United States)

    Jarosz, Renata; Littlepage, Meagan M; Creasey, Graham; McKenna, Stephen L

    2012-01-01

    The management of chronic respiratory insufficiency and/or long-term inability to breathe independently has traditionally been via positive-pressure ventilation through a mechanical ventilator. Although life-sustaining, it is associated with limitations of function, lack of independence, decreased quality of life, sleep disturbance, and increased risk for infections. In addition, its mechanical and electronic complexity requires full understanding of the possible malfunctions by patients and caregivers. Ventilator-associated pneumonia, tracheal injury, and equipment malfunction account for common complications of prolonged ventilation, and respiratory infections are the most common cause of death in spinal cord-injured patients. The development of functional electric stimulation (FES) as an alternative to mechanical ventilation has been motivated by a goal to improve the quality of life of affected individuals. In this article, we will review the physiology, types, characteristics, risks and benefits, surgical techniques, and complications of the 2 commercially available FES strategies - phrenic nerve pacing (PNP) and diaphragm motor point pacing (DMPP).

  15. Models of brainstem responses to bilateral electrical stimulation.

    Science.gov (United States)

    Colburn, H Steven; Chung, Yoojin; Zhou, Yi; Brughera, Andrew

    2009-03-01

    A simple, biophysically specified cell model is used to predict responses of binaurally sensitive neurons to patterns of input spikes that represent stimulation by acoustic and electric waveforms. Specifically, the effects of changes in parameters of input spike trains on model responses to interaural time difference (ITD) were studied for low-frequency periodic stimuli, with or without amplitude modulation. Simulations were limited to purely excitatory, bilaterally driven cell models with basic ionic currents and multiple input fibers. Parameters explored include average firing rate, synchrony index, modulation frequency, and latency dispersion of the input trains as well as the excitatory conductance and time constant of individual synapses in the cell model. Results are compared to physiological recordings from the inferior colliculus (IC) and discussed in terms of ITD-discrimination abilities of listeners with cochlear implants. Several empirically observed aspects of ITD sensitivity were simulated without evoking complex neural processing. Specifically, our results show saturation effects in rate-ITD curves, the absence of sustained responses to high-rate unmodulated pulse trains, the renewal of sensitivity to ITD in high-rate trains when inputs are amplitude-modulated, and interactions between envelope and fine-structure delays for some modulation frequencies.

  16. Microcurrent electrical nerve stimulation facilitates regrowth of mouse soleus muscle.

    Science.gov (United States)

    Ohno, Yoshitaka; Fujiya, Hiroto; Goto, Ayumi; Nakamura, Ayane; Nishiura, Yuka; Sugiura, Takao; Ohira, Yoshinobu; Yoshioka, Toshitada; Goto, Katsumasa

    2013-01-01

    Microcurrent electrical nerve stimulation (MENS) has been used to facilitate recovery from skeletal muscle injury. However, the effects of MENS on unloading-associated atrophied skeletal muscle remain unclear. Effects of MENS on the regrowing process of unloading-associated atrophied skeletal muscle were investigated. Male C57BL/6J mice (10-week old) were randomly assigned to untreated normal recovery (C) and MENS-treated (M) groups. Mice of both groups are subjected to continuous hindlimb suspension (HS) for 2 weeks followed by 7 days of ambulation recovery. Mice in M group were treated with MENS for 60 min 1, 3, and 5 days following HS, respectively, under anesthesia. The intensity, the frequency, and the pulse width of MENS were set at 10 μA, 0.3 Hz, and 250 msec, respectively. Soleus muscles were dissected before and immediately after, 1, 3 and 7 days after HS. Soleus muscle wet weight and protein content were decreased by HS. The regrowth of atrophied soleus muscle in M group was faster than that in C group. Decrease in the reloading-induced necrosis of atrophied soleus was facilitated by MENS. Significant increases in phosphorylated levels of p70 S6 kinase and protein kinase B (Akt) in M group were observed, compared with C group. These observations are consistent with that MENS facilitated regrowth of atrophied soleus muscle. MENS may be a potential extracellular stimulus to activate the intracellular signals involved in protein synthesis.

  17. Transcutaneous electrical nerve stimulation therapy in reduction of orofacial pain

    Directory of Open Access Journals (Sweden)

    Đorđević Igor

    2014-01-01

    Full Text Available Introduction. Patients with craniomandibular disorders suffer from hypertonic, fatigued and painful masticatory muscles. This condition can lead to limitation of mandibular jaw movements. All of these symptoms and signs are included in myofascial pain dysfunction syndrome. Transcutaneous electrical nerve stimulation (TENS has been used for treatment of these patients. Objective. The aim of this study was to assess the effect of TENS therapy on chronic pain reduction in patients with the muscular dysfunction symptom. Methods. In order to evaluate the effect of TENS therapy before and after the treatment, Craniomandibular Index (Helkimo was used. Pain intensity was measured by VAS. Patients had TENS treatment over two-week period. BURST TENS modality was used. Current intensity was individually adjusted. Results. Two patients did not respond to TENS therapy. Complete pain reduction was recorded in 8 patients, while pain reduction was not significantly different after TENS therapy in 10 patients. Conclusion. TENS therapy was confirmed as therapeutic procedure in orofacial muscle relaxation and pain reduction.

  18. Enhancing vestibular function in the elderly with imperceptible electrical stimulation.

    Science.gov (United States)

    Serrador, Jorge M; Deegan, Brian M; Geraghty, Maria C; Wood, Scott J

    2018-01-10

    Age-related loss of vestibular function can result in decrements in gaze stabilization and increased fall risk in the elderly. This study was designed to see if low levels of electrical stochastic noise applied transcutaneously to the vestibular system can improve a gaze stabilization reflex in young and elderly subject groups. Ocular counter-rolling (OCR) using a video-based technique was obtained in 16 subjects during low frequency passive roll tilts. Consistent with previous studies, there was a significant reduction in OCR gains in the elderly compared to the young group. Imperceptible stochastic noise significantly increased OCR in the elderly (Mean 23%, CI: 17-35%). Increases in OCR gain were greatest for those with lowest baseline gain and were negligible in those with normal gain. Since stimulation was effective at low levels undetectable to subjects, stochastic noise may provide a new treatment alternative to enhance vestibular function, specifically otolith-ocular reflexes, in the elderly or patient populations with reduced otolith-ocular function.

  19. Efficacy of Carcass Electrical Stimulation in Meat Quality Enhancement: A Review

    OpenAIRE

    Kazeem Dauda Adeyemi; Awis Qurni Sazili

    2014-01-01

    The use of electrical stimulation (ES) as a management tool to improve meat quality and efficiency of meat processing is reviewed. The basis of the efficacy of ES is its ability to fast track postmortem glycolysis, which in turn stimulates myriad histological, physical, biochemical, biophysical and physiological changes in the postmortem muscle. Electrical stimulation hastens the onset and resolution of rigor mortis thereby reducing processing time and labor and plays a vital role in improvin...

  20. Electrical stimulation vs. pulsed and continuous-wave optical stimulation of the rat prostate cavernous nerves, in vivo

    Science.gov (United States)

    Perkins, William C.; Lagoda, Gwen A.; Burnett, Arthur; Fried, Nathaniel M.

    2015-07-01

    Identification and preservation of the cavernous nerves (CNs) during prostate cancer surgery is critical for post-operative sexual function. Electrical nerve stimulation (ENS) mapping has previously been tested as an intraoperative tool for CN identification, but was found to be unreliable. ENS is limited by the need for electrode-tissue contact, poor spatial precision from electrical current spreading, and stimulation artifacts interfering with detection. Alternatively, optical nerve stimulation (ONS) provides noncontact stimulation, improved spatial selectivity, and elimination of stimulation artifacts. This study compares ENS to pulsed/CW ONS to explore the ONS mechanism. A total of eighty stimulations were performed in 5 rats, in vivo. ENS (4 V, 5 ms, 10 Hz) was compared to ONS using a pulsed diode laser nerve stimulator (1873 nm, 5 ms, 10 Hz) or CW diode laser nerve stimulator (1455 nm). Intracavernous pressure (ICP) response and nerve compound action potentials (nCAPs) were measured. All three stimulation modes (ENS, ONS-CW, ONS-P) produced comparable ICP magnitudes. However, ENS demonstrated more rapid ICP response times and well defined nCAPs compared to unmeasurable nCAPs for ONS. Further experiments measuring single action potentials during ENS and ONS are warranted to further understand differences in the ENS and ONS mechanisms.

  1. Simulation of the Electrical Field in Equine Larynx to Optimize Functional Electrical Stimulation in Denervated Musculus Cricoarythenoideus Dorsalis

    OpenAIRE

    Martin Reichel; Johannes Martinek

    2014-01-01

    Distribution of the electrical field is very important to activate muscle and nerve cells properly. One therapeutic method to treat Recurrent Laryngeal Neuropathy (RLN) in horses can be performed by Functional Electrical Stimulation (FES). Current method to optimize the stimulation effect is to use implanted quadripolar electrodes to the musculus cricoarythenoideus dorsalis (CAD) and testing electrode configuration until best possible optimum is reached. For better understanding and finding o...

  2. Simulation of the electrical field in equine larynx to optimize functional electrical stimulation in denervated musculus cricoarythenoideus dorsalis

    OpenAIRE

    Martin Reichel; Johannes Martinek

    2014-01-01

    Distribution of the electrical field is very important to activate muscle and nerve cells properly. One therapeutic method to treat Recurrent Laryngeal Neuropathy (RLN) in horses can be performed by Functional Electrical Stimulation (FES). Current method to optimize the stimulation effect is to use implanted quadripolar electrodes to the musculus cricoarythenoideus dorsalis (CAD) and testing electrode configuration until best possible optimum is reached. For better understanding and finding o...

  3. Anti-stress effects of transcutaneous electrical nerve stimulation (TENS) on colonic motility in rats.

    Science.gov (United States)

    Yoshimoto, Sazu; Babygirija, Reji; Dobner, Anthony; Ludwig, Kirk; Takahashi, Toku

    2012-05-01

    Disorders of colonic motility may contribute to symptoms in patients with irritable bowel syndrome (IBS), and stress is widely believed to play a major role in developing IBS. Stress increases corticotropin releasing factor (CRF) of the hypothalamus, resulting in acceleration of colonic transit in rodents. In contrast, hypothalamic oxytocin (OXT) has an anti-stress effect via inhibiting CRF expression and hypothalamic-pituitary-adrenal axis activity. Although transcutaneous electrical nerve stimulation (TENS) and acupuncture have been shown to have anti-stress effects, the mechanism of the beneficial effects remains unknown. We tested the hypothesis that TENS upregulates hypothalamic OXT expression resulting in reduced CRF expression and restoration of colonic dysmotility in response to chronic stress. Male SD rats received different types of stressors for seven consecutive days (chronic heterotypic stress). TENS was applied to the bilateral hind limbs every other day before stress loading. Another group of rats did not receive TENS treatment. TENS significantly attenuated accelerated colonic transit induced by chronic heterotypic stress, which was antagonized by a central injection of an OXT antagonist. Immunohistochemical study showed that TENS increased OXT expression and decreased CRF expression at the paraventricular nucleus (PVN) following chronic heterotypic stress. It is suggested that TENS upregulates hypothalamic OXT expression which acts as an anti-stressor agent and mediates restored colonic dysmotility following chronic stress. TENS may be useful to treat gastrointestinal symptoms associated with stress.

  4. A Novel In Vitro System for Comparative Analyses of Bone Cells and Bacteria under Electrical Stimulation

    Directory of Open Access Journals (Sweden)

    Thomas Josef Dauben

    2016-01-01

    Full Text Available Electrical stimulation is a promising approach to enhance bone regeneration while having potential to inhibit bacterial growth. To investigate effects of alternating electric field stimulation on both human osteoblasts and bacteria, a novel in vitro system was designed. Electric field distribution was simulated numerically and proved by experimental validation. Cells were stimulated on Ti6Al4V electrodes and in short distance to electrodes. Bacterial growth was enumerated in supernatant and on the electrode surface and biofilm formation was quantified. Electrical stimulation modulated gene expression of osteoblastic differentiation markers in a voltage-dependent manner, resulting in significantly enhanced osteocalcin mRNA synthesis rate on electrodes after stimulation with 1.4VRMS. While collagen type I synthesis increased when stimulated with 0.2VRMS, it decreased after stimulation with 1.4VRMS. Only slight and infrequent influence on bacterial growth was observed following stimulations with 0.2VRMS and 1.4VRMS after 48 and 72 h, respectively. In summary this novel test system is applicable for extended in vitro studies concerning definition of appropriate stimulation parameters for bone cell growth and differentiation, bacterial growth suppression, and investigation of general effects of electrical stimulation.

  5. A Novel In Vitro System for Comparative Analyses of Bone Cells and Bacteria under Electrical Stimulation

    Science.gov (United States)

    Zaatreh, Sarah; Kreikemeyer, Bernd

    2016-01-01

    Electrical stimulation is a promising approach to enhance bone regeneration while having potential to inhibit bacterial growth. To investigate effects of alternating electric field stimulation on both human osteoblasts and bacteria, a novel in vitro system was designed. Electric field distribution was simulated numerically and proved by experimental validation. Cells were stimulated on Ti6Al4V electrodes and in short distance to electrodes. Bacterial growth was enumerated in supernatant and on the electrode surface and biofilm formation was quantified. Electrical stimulation modulated gene expression of osteoblastic differentiation markers in a voltage-dependent manner, resulting in significantly enhanced osteocalcin mRNA synthesis rate on electrodes after stimulation with 1.4V RMS. While collagen type I synthesis increased when stimulated with 0.2V RMS, it decreased after stimulation with 1.4V RMS. Only slight and infrequent influence on bacterial growth was observed following stimulations with 0.2V RMS and 1.4V RMS after 48 and 72 h, respectively. In summary this novel test system is applicable for extended in vitro studies concerning definition of appropriate stimulation parameters for bone cell growth and differentiation, bacterial growth suppression, and investigation of general effects of electrical stimulation. PMID:28044132

  6. Fundamentals of Transcranial Electric and Magnetic Stimulation Dose: Definition, Selection, and Reporting Practices

    Science.gov (United States)

    Peterchev, Angel V.; Wagner, Timothy A.; Miranda, Pedro C.; Nitsche, Michael A.; Paulus, Walter; Lisanby, Sarah H.; Pascual-Leone, Alvaro; Bikson, Marom

    2011-01-01

    The growing use of transcranial electric and magnetic (EM) brain stimulation in basic research and in clinical applications necessitates a clear understanding of what constitutes the dose of EM stimulation and how it should be reported. The biological effects of EM stimulation are mediated through an electromagnetic field injected (via electric stimulation) or induced (via magnetic stimulation) in the body. Therefore, transcranial EM stimulation dose ought to be defined by all parameters of the stimulation device that affect the electromagnetic field generated in the body, including the stimulation electrode or coil configuration parameters: shape, size, position, and electrical properties, as well as the electrode or coil current (or voltage) waveform parameters: pulse shape, amplitude, width, polarity, and repetition frequency; duration of and interval between bursts or trains of pulses; total number of pulses; and interval between stimulation sessions and total number of sessions. Knowledge of the electromagnetic field generated in the body may not be sufficient but is necessary to understand the biological effects of EM stimulation. We believe that reporting of EM stimulation dose should be guided by the principle of reproducibility: sufficient information about the stimulation parameters should be provided so that the dose can be replicated. This paper provides fundamental definition and principles for reporting of dose that encompass any transcranial EM brain stimulation protocol. PMID:22305345

  7. Transcutaneous electrical nerve stimulation (TENS) for pain management in labour

    Science.gov (United States)

    Dowswell, Therese; Bedwell, Carol; Lavender, Tina; Neilson, James P

    2014-01-01

    Background Transcutaneous nerve stimulation (TENS) has been proposed as a means of reducing pain in labour. The TENS unit emits low-voltage electrical impulses which vary in frequency and intensity. During labour, TENS electrodes are generally placed on the lower back, although TENS may be used to stimulate acupuncture points or other parts of the body. The physiological mechanisms whereby TENS relieves pain are uncertain. TENS machines are frequently operated by women, which may increase a sense of control in labour. Objectives To assess the effects of TENS on pain in labour. Search methods We searched the Cochrane Pregnancy and Childbirth Group’s Trials Register (30 April 2011) and reference lists of retrieved papers. Selection criteria Randomised controlled trials comparing women receiving TENS for pain management in labour versus routine care, alternative non-pharmacological methods of pain relief, or placebo devices. We included all types of TENS machines. Data collection and analysis Two review authors assessed for inclusion all trials identified by the search strategy, carried out data extraction and assessed risk of bias. We have recorded reasons for excluding studies. Main results Seventeen trials with 1466 women contribute data to the review. Thirteen examined TENS applied to the back, two to acupuncture points, and two to the cranium. Overall, there was little difference in pain ratings between TENS and control groups, although women receiving TENS to acupuncture points were less likely to report severe pain (average risk ratio 0.41, 95% confidence interval 0.31 to 0.54; measured in two studies). The majority of women using TENS said they would be willing to use it again in a future labour. Where TENS was used as an adjunct to epidural analgesia there was no evidence that it reduced pain. There was no consistent evidence that TENS had any impact on interventions and outcomes in labour. There was little information on outcomes for mothers and babies. No

  8. Gastric electrical stimulation for treatment of clinically severe gastroparesis

    Directory of Open Access Journals (Sweden)

    Naga Venkatesh G Jayanthi

    2013-01-01

    Full Text Available Background: Severe, drug-resistant gastroparesis is a debilitating condition. Several, but not all, patients can get significant relief from nausea and vomiting by gastric electrical stimulation (GES. A trial of temporary, endoscopically delivered GES may be of predictive value to select patients for laparoscopic-implantation of a permanent GES device. Materials and Methods: We conducted a clinical audit of consecutive gastroparesis patients, who had been selected for GES, from May 2008 to January 2012. Delayed gastric emptying was diagnosed by scintigraphy of ≥50% global improvement in symptom-severity and well-being was a good response. Results: There were 71 patients (51 women, 72% with a median age of 42 years (range: 14-69. The aetiology of gastroparesis was idiopathic (43 patients, 61%, diabetes (15, 21%, or post-surgical (anti-reflux surgery, 6 patients; Roux-en-Y gastric bypass, 3; subtotal gastrectomy, 1; cardiomyotomy, 1; other gastric surgery, 2 (18%. At presentation, oral nutrition was supplemented by naso-jejunal tube feeding in 7 patients, surgical jejunostomy in 8, or parenterally in 1 (total 16 patients; 22%. Previous intervention included endoscopic injection of botulinum toxin (botox into the pylorus in 16 patients (22%, pyloroplasty in 2, distal gastrectomy in 1, and gastrojejunostomy in 1. It was decided to directly proceed with permanent GES in 4 patients. Of the remaining, 51 patients have currently completed a trial of temporary stimulation and 39 (77% had a good response and were selected for permanent GES, which has been completed in 35 patients. Outcome data are currently available for 31 patients (idiopathic, 21 patients; diabetes, 3; post-surgical, 7 with a median follow-up period of 10 months (1-28; 22 patients (71% had a good response to permanent GES, these included 14 (68% with idiopathic, 5 (71% with post-surgical, and remaining 3 with diabetic gastroparesis. Conclusions: Overall, 71% of well-selected patients

  9. Identification of key factors in Accelerated Low Water Corrosion through experimental simulation of tidal conditions: influence of stimulated indigenous microbiota

    NARCIS (Netherlands)

    Marty, F.; Gueuné, H.; Malard, E.; Sánchez-Amaya, J.M.; Sjögren, L.; Abbas, B.; Quillet, L.; van Loosdrecht, M.C.M.; Muyzer, G.

    2014-01-01

    Biotic and abiotic factors favoring Accelerated Low Water Corrosion (ALWC) on harbor steel structures remain unclear warranting their study under controlled experimental tidal conditions. Initial stimulation of marine microbial consortia by a pulse of organic matter resulted in localized corrosion

  10. Skin collagen reproduction increased by ascorbic acid derivative iontophoresis by frequent-reversal bipolar electric stimulation.

    Science.gov (United States)

    Hori, Yusuke; Akimoto, Ryuji; Hori, Akiko; Kato, Katsuhiko; Chino, Daisuke; Matsumoto, Shohei; Kamiya, Shohei; Watanabe, Yasuo

    2009-01-01

    The effect of the iontophoresis of ascorbic acid (Vitamin C; VC) derivative with frequent-reversal bipolar electric stimulation on the production of collagen in rat skin was evaluated in terms of hydroxyproline content through high-performance liquid chromatography. First, a control group was not given electrical stimulation and four groups were stimulated with a unipolar pulse for 0.5-10 min every day for one week. The hydroxyproline level in the skin was increased depending on the length of the stimulation. Second, a control group was not given any electrical stimulation, and three groups were treated with (a) VC solution without any stimulation, (b) a bipolar pulse for 10 min with saline, or (c) a bipolar pulse for 5 min with the VC solution. Significant increases were found in all the stimulation groups, although these treated with the VC solution without any stimulation did not have any effects compared to the control. Thus, in order to increase the hydroxyproline levels in skin, a VC must be delivered with bipolar stimulation as a method of iontophoresis. These results suggest that our newly developed electric stimulation is effective at increasing skin collagen content, and that bipolar stimulation is more effective on the iontophoresis of not only VC but also some medicines such as low- and high-molecular drugs directed to the target organ (7).

  11. Assessing kinematics and kinetics of functional electrical stimulation rowing.

    Science.gov (United States)

    Draghici, Adina E; Picard, Glen; Taylor, J Andrew; Shefelbine, Sandra J

    2017-02-28

    Hybrid functional electrical stimulation (FES) rowing has positive effects on cardiovascular fitness, producing significantly greater aerobic power than either upper body or FES exercise alone. However, there is minimal information on the kinematics, kinetics, and mechanical efficiency of FES-rowing in the spinal cord injured (SCI) population. This study examined the biomechanics of FES-rowing to determine how motions, forces, and aerobic demand change with increasing intensity. Six individuals with SCI and six able-bodied subjects performed a progressive aerobic capacity rowing test. Differences in kinematics (motion profiles), kinetics (forces produced by the feet and arms), external mechanical work, and mechanical efficiency (work produced/volume of oxygen consumed) were compared in able-bodied rowing vs. SCI FES-rowing at three comparable subpeak workloads. With increasing exercise intensity (measured as wattage), able-bodied rowing increased stroke rate by decreasing recovery time, while FES-rowing maintained a constant stroke rate, with no change in drive or recovery times. While able-bodied rowers increased leg and arm forces with increasing intensity, FES-rowers used only their arms to achieve a higher intensity with a constant and relatively low contribution of the legs. Oxygen consumption increased in both groups, but more so in able-bodied rowers, resulting in able-bodied rowers having twice the mechanical efficiency of FES-rowers. Our results suggest that despite its ability to allow for whole body exercise, the total force output achievable with FES-rowing results in only modest loading of the legs that affects overall rowing performance and that may limit forces applied to bone. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Higher success rate with transcranial electrical stimulation of motor-evoked potentials using constant-voltage stimulation compared with constant-current stimulation in patients undergoing spinal surgery.

    Science.gov (United States)

    Shigematsu, Hideki; Kawaguchi, Masahiko; Hayashi, Hironobu; Takatani, Tsunenori; Iwata, Eiichiro; Tanaka, Masato; Okuda, Akinori; Morimoto, Yasuhiko; Masuda, Keisuke; Tanaka, Yuu; Tanaka, Yasuhito

    2017-10-01

    During spine surgery, the spinal cord is electrophysiologically monitored via transcranial electrical stimulation of motor-evoked potentials (TES-MEPs) to prevent injury. Transcranial electrical stimulation of motor-evoked potential involves the use of either constant-current or constant-voltage stimulation; however, there are few comparative data available regarding their ability to adequately elicit compound motor action potentials. We hypothesized that the success rates of TES-MEP recordings would be similar between constant-current and constant-voltage stimulations in patients undergoing spine surgery. The objective of this study was to compare the success rates of TES-MEP recordings between constant-current and constant-voltage stimulation. This is a prospective, within-subject study. Data from 100 patients undergoing spinal surgery at the cervical, thoracic, or lumbar level were analyzed. The success rates of the TES-MEP recordings from each muscle were examined. Transcranial electrical stimulation with constant-current and constant-voltage stimulations at the C3 and C4 electrode positions (international "10-20" system) was applied to each patient. Compound muscle action potentials were bilaterally recorded from the abductor pollicis brevis (APB), deltoid (Del), abductor hallucis (AH), tibialis anterior (TA), gastrocnemius (GC), and quadriceps (Quad) muscles. The success rates of the TES-MEP recordings from the right Del, right APB, bilateral Quad, right TA, right GC, and bilateral AH muscles were significantly higher using constant-voltage stimulation than those using constant-current stimulation. The overall success rates with constant-voltage and constant-current stimulations were 86.3% and 68.8%, respectively (risk ratio 1.25 [95% confidence interval: 1.20-1.31]). The success rates of TES-MEP recordings were higher using constant-voltage stimulation compared with constant-current stimulation in patients undergoing spinal surgery. Copyright © 2017

  13. Transcutaneous electrical nerve stimulation (TENS) for neuropathic pain in adults.

    Science.gov (United States)

    Gibson, William; Wand, Benedict M; O'Connell, Neil E

    2017-09-14

    Neuropathic pain, which is due to nerve disease or damage, represents a significant burden on people and society. It can be particularly unpleasant and achieving adequate symptom control can be difficult. Non-pharmacological methods of treatment are often employed by people with neuropathic pain and may include transcutaneous electrical nerve stimulation (TENS). This review supersedes one Cochrane Review 'Transcutaneous electrical nerve stimulation (TENS) for chronic pain' (Nnoaham 2014) and one withdrawn protocol 'Transcutaneous electrical nerve stimulation (TENS) for neuropathic pain in adults' (Claydon 2014). This review replaces the original protocol for neuropathic pain that was withdrawn. To determine the analgesic effectiveness of TENS versus placebo (sham) TENS, TENS versus usual care, TENS versus no treatment and TENS in addition to usual care versus usual care alone in the management of neuropathic pain in adults. We searched CENTRAL, MEDLINE, Embase, PsycINFO, AMED, CINAHL, Web of Science, PEDro, LILACS (up to September 2016) and various clinical trials registries. We also searched bibliographies of included studies for further relevant studies. We included randomised controlled trials where TENS was evaluated in the treatment of central or peripheral neuropathic pain. We included studies if they investigated the following: TENS versus placebo (sham) TENS, TENS versus usual care, TENS versus no treatment and TENS in addition to usual care versus usual care alone in the management of neuropathic pain in adults. Two review authors independently screened all database search results and identified papers requiring full-text assessment. Subsequently, two review authors independently applied inclusion/exclusion criteria to these studies. The same review authors then independently extracted data, assessed for risk of bias using the Cochrane standard tool and rated the quality of evidence using GRADE. We included 15 studies with 724 participants. We found a

  14. Model study of combined electrical and near-infrared neural stimulation on the bullfrog sciatic nerve.

    Science.gov (United States)

    You, Mengxian; Mou, Zongxia

    2017-07-01

    This paper implemented a model study of combined electrical and near-infrared (808 nm) neural stimulation (NINS) on the bullfrog sciatic nerve. The model includes a COMSOL model to calculate the electric-field distribution of the surrounding area of the nerve, a Monte Carlo model to simulate light transport and absorption in the bullfrog sciatic nerve during NINS, and a NEURON model to simulate the neural electrophysiology changes under electrical stimulus and laser irradiation. The optical thermal effect is considered the main mechanism during NINS. Therefore, thermal change during laser irradiation was calculated by the Monte Carlo method, and the temperature distribution was then transferred to the NEURON model to stimulate the sciatic nerve. The effects on thermal response by adjusting the laser spot size, energy of the beam, and the absorption coefficient of the nerve are analyzed. The effect of the ambient temperature on the electrical stimulation or laser stimulation and the interaction between laser irradiation and electrical stimulation are also studied. The results indicate that the needed stimulus threshold for neural activation or inhibition is reduced by laser irradiation. Additionally, the needed laser energy for blocking the action potential is reduced by electrical stimulus. Both electrical and laser stimulation are affected by the ambient temperature. These results provide references for subsequent animal experiments and could be of great help to future basic and applied studies of infrared neural stimulation (INS).

  15. Transcutaneus electrical nerve stimulation for overactive bladder increases rectal motor activity in children: a randomized controlled study

    DEFF Research Database (Denmark)

    Jønsson, Iben; Hagstrøm, Søren; Siggaard, Charlotte

    Transcutaneus electrical nerve stimulation for overactive bladder increases rectal motor activity in children: a randomized controlled study......Transcutaneus electrical nerve stimulation for overactive bladder increases rectal motor activity in children: a randomized controlled study...

  16. Electrical stimulation enhances cell migration and integrative repair in the meniscus

    Science.gov (United States)

    Yuan, Xiaoning; Arkonac, Derya E.; Chao, Pen-Hsiu Grace; Vunjak-Novakovic, Gordana

    2014-01-01

    Electrical signals have been applied towards the repair of articular tissues in the laboratory and clinical settings for over seventy years. We focus on healing of the meniscus, a tissue essential to knee function with limited innate repair potential, which has been largely unexplored in the context of electrical stimulation. Here we demonstrate for the first time that electrical stimulation enhances meniscus cell migration and integrative tissue repair. We optimize pulsatile direct current electrical stimulation parameters on cells at the micro-scale, and apply these to healing of full-thickness defects in explants at the macro-scale. We report increased expression of the adenosine A2b receptor in meniscus cells after stimulation at the micro- and macro-scale, and propose a role for A2bR in meniscus electrotransduction. Taken together, these findings advance our understanding of the effects of electrical signals and their mechanisms of action, and contribute to developing electrotherapeutic strategies for meniscus repair.

  17. Delay-Dependent Response in Weakly Electric Fish under Closed-Loop Pulse Stimulation.

    Science.gov (United States)

    Forlim, Caroline Garcia; Pinto, Reynaldo Daniel; Varona, Pablo; Rodríguez, Francisco B

    2015-01-01

    In this paper, we apply a real time activity-dependent protocol to study how freely swimming weakly electric fish produce and process the timing of their own electric signals. Specifically, we address this study in the elephant fish, Gnathonemus petersii, an animal that uses weak discharges to locate obstacles or food while navigating, as well as for electro-communication with conspecifics. To investigate how the inter pulse intervals vary in response to external stimuli, we compare the response to a simple closed-loop stimulation protocol and the signals generated without electrical stimulation. The activity-dependent stimulation protocol explores different stimulus delivery delays relative to the fish's own electric discharges. We show that there is a critical time delay in this closed-loop interaction, as the largest changes in inter pulse intervals occur when the stimulation delay is below 100 ms. We also discuss the implications of these findings in the context of information processing in weakly electric fish.

  18. Gastric electrical stimulation: an evidence-based analysis.

    Science.gov (United States)

    2006-01-01

    The objective of this analysis was to assess the effectiveness, safety and cost-effectiveness of gastric electrical stimulation (GES) for the treatment of chronic, symptomatic refractory gastroparesis and morbid obesity. GASTROPARESIS - EPIDEMIOLOGY: Gastroparesis (GP) broadly refers to impaired gastric emptying in the absence of obstruction. Clinically, this can range from the incidental detection of delayed gastric emptying in an asymptomatic person to patients with severe nausea, vomiting and malnutrition. Symptoms of GP are nonspecific and may mimic structural disorders such as ulcer disease, partial gastric or small bowel obstruction, gastric cancer, and pancreaticobiliary disorders. Gastroparesis may occur in association with diabetes, gastric surgery (consequence of peptic ulcer surgery and vagotomy) or for unknown reasons (idiopathic gastroparesis). Symptoms include early satiety, nausea, vomiting, abdominal pain and weight loss. The majority of patients with GP are women. The relationship between upper gastrointestinal symptoms and the rate of gastric emptying is considered to be weak. Some patients with markedly delayed gastric emptying are asymptomatic and sometimes, severe symptoms may remit spontaneously. Idiopathic GP may represent the most common form of GP. In one tertiary referral retrospective series, the etiologies in 146 GP patients were 36% idiopathic, 29% diabetic, 13% postgastric surgery, 7.5% Parkinson's disease, 4.8% collagen vascular disorders, 4.1% intestinal pseudoobstruction and 6% miscellaneous causes. The true prevalence of digestive symptoms in patients with diabetes and the relationship of these symptoms to delayed gastric emptying are unknown. Delayed gastric emptying is present in 27% to 58% of patients with type 1 diabetes and 30% with type 2 diabetes. However, highly variable rates of gastric emptying have been reported in type 1 and 2 diabetes, suggesting that development of GP in patients with diabetes is neither universal nor

  19. Transcutaneous electrical nerve stimulation (TENS) for fibromyalgia in adults.

    Science.gov (United States)

    Johnson, Mark I; Claydon, Leica S; Herbison, G Peter; Jones, Gareth; Paley, Carole A

    2017-10-09

    Fibromyalgia is characterised by persistent, widespread pain; sleep problems; and fatigue. Transcutaneous electrical nerve stimulation (TENS) is the delivery of pulsed electrical currents across the intact surface of the skin to stimulate peripheral nerves and is used extensively to manage painful conditions. TENS is inexpensive, safe, and can be self-administered. TENS reduces pain during movement in some people so it may be a useful adjunct to assist participation in exercise and activities of daily living. To date, there has been only one systematic review in 2012 which included TENS, amongst other treatments, for fibromyalgia, and the authors concluded that TENS was not effective. To assess the analgesic efficacy and adverse events of TENS alone or added to usual care (including exercise) compared with placebo (sham) TENS; no treatment; exercise alone; or other treatment including medication, electroacupuncture, warmth therapy, or hydrotherapy for fibromyalgia in adults. We searched the following electronic databases up to 18 January 2017: CENTRAL (CRSO); MEDLINE (Ovid); Embase (Ovid); CINAHL (EBSCO); PsycINFO (Ovid); LILACS; PEDRO; Web of Science (ISI); AMED (Ovid); and SPORTDiscus (EBSCO). We also searched three trial registries. There were no language restrictions. We included randomised controlled trials (RCTs) or quasi-randomised trials of TENS treatment for pain associated with fibromyalgia in adults. We included cross-over and parallel-group trial designs. We included studies that evaluated TENS administered using non-invasive techniques at intensities that produced perceptible TENS sensations during stimulation at either the site of pain or over nerve bundles proximal (or near) to the site of pain. We included TENS administered as a sole treatment or TENS in combination with other treatments, and TENS given as a single treatment or as a course of treatments. Two review authors independently determined study eligibility by assessing each record and

  20. Relation between stimulation characteristics and clinical outcome in studies using electrical stimulation to improve motor control of the upper extremity in stroke

    NARCIS (Netherlands)

    de Kroon, Joke R.; IJzerman, Maarten Joost; Chae, John; Lankhorst, Gustaaf J.; Zilvold, G.; Zilvold, Gerrit

    Objective: Electrical stimulation can be applied in a variety of ways to the hemiparetic upper extremity following stroke. The aim of this review is to explore the relationship between characteristics of stimulation and the effect of electrical stimulation on the recovery of upper limb motor control

  1. Relation between stimulation characteristics and clinical outcome in studies using electrical stimulation to improve motor control of the upper extremity in stroke

    NARCIS (Netherlands)

    de Kroon, J.R.; IJzerman, M.J.; Chae, J.; Lankhorst, G.J.; Zilvold, G.

    2005-01-01

    Objective: Electrical stimulation can be applied in a variety of ways to the hemiparetic upper extremity following stroke. The aim of this review is to explore the relationship between characteristics of stimulation and the effect of electrical stimulation on the recovery of upper limb motor control

  2. Intraoperative acceleration measurements to quantify improvement in tremor during deep brain stimulation surgery.

    Science.gov (United States)

    Shah, Ashesh; Coste, Jérôme; Lemaire, Jean-Jacques; Taub, Ethan; Schüpbach, W M Michael; Pollo, Claudio; Schkommodau, Erik; Guzman, Raphael; Hemm-Ode, Simone

    2017-05-01

    Deep brain stimulation (DBS) surgery is extensively used in the treatment of movement disorders. Nevertheless, methods to evaluate the clinical response during intraoperative stimulation tests to identify the optimal position for the implantation of the chronic DBS lead remain subjective. In this paper, we describe a new, versatile method for quantitative intraoperative evaluation of improvement in tremor with an acceleration sensor that is mounted on the patient's wrist during surgery. At each anatomical test position, the improvement in tremor compared to the initial tremor is estimated on the basis of extracted outcome measures. This method was tested on 15 tremor patients undergoing DBS surgery in two centers. Data from 359 stimulation tests were acquired. Our results suggest that accelerometric evaluation detects tremor changes more sensitively than subjective visual ratings. The effective stimulation current amplitudes identified from the quantitative data (1.1 ± 0.8 mA) are lower than those identified by visual evaluation (1.7 ± 0.8 mA) for similar improvement in tremor. Additionally, if these data had been used to choose the chronic implant position of the DBS lead, 15 of the 26 choices would have been different. These results show that our method of accelerometric evaluation can potentially improve DBS targeting.

  3. Semiconditional electrical stimulation of pudendal nerve afferents stimulation to manage neurogenic detrusor overactivity in patients with spinal cord injury.

    Science.gov (United States)

    Lee, Young-Hee; Kim, Jung Moon; Im, Hyung Tae; Lee, Kye-Wook; Kim, Sung Hoon; Hur, Dong Min

    2011-10-01

    To evaluate the effect of semiconditional electrical stimulation of the pudendal nerve afferents for the neurogenic detrusor overactivity in patients with spinal cord injury. Forty patients (36 males, 4 males) with spinal cord injury who had urinary incontinence and frequency, as well as felt bladder contraction with bladder filling sense or autonomic dysreflexic symptom participated in this study. Patients with neurogenic detrusor overactivity were subdivided into complete injury and incomplete injury groups by ASIA classification and subdivided into tetraplegia and paraplegia groups by neurologic level of injury. Bladder function, such as bladder volumes infused to the bladder until the first occurrence of neurogenic detrusor overactivity (V(ini)) and the last contraction suppressed by electrical stimulation (V(max)) was measured by water cystometry (CMG) and compared with the results of each subgroup. Among the 40 subjects, 35 patients showed neurogenic detrusor overactivity in the CMG study. Among these 35 patients, detrusor overactivity was suppressed effectively by pudendal nerve afferent electrical stimulation in 32 patients. The infusion volume until the occurrence of the first reflex contraction (V(ini)) was 99.4±80.3 ml. The volume of saline infused to the bladder until the last contraction suppressed by semiconditional pudendal nerve stimulation (V(max)) was 274.3±93.2 ml, which was significantly greater than V(ini). In patients with good response to the pudendal nerve afferent stimulation, the bladder volume significantly increased by stimulation in all the patients. In this study, semiconditional electrical stimulation on the dorsal penile afferent nerve could effectively inhibit neurogenic detrusor overactivity and increase bladder volume in patients with spinal cord injury.

  4. Tissue heterogeneity as a mechanism for localized neural stimulation by applied electric fields

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, P C [Institute of Biophysics and Biomedical Engineering, Faculty of Sciences, University of Lisbon, 1749-016 Lisbon (Portugal); Correia, L [Institute of Biophysics and Biomedical Engineering, Faculty of Sciences, University of Lisbon, 1749-016 Lisbon (Portugal); Salvador, R [Institute of Biophysics and Biomedical Engineering, Faculty of Sciences, University of Lisbon, 1749-016 Lisbon (Portugal); Basser, P J [Section on Tissue Biophysics and Biomimetics, NICHD, National Institutes of Health, Bethesda, MD 20892-1428 (United States)

    2007-09-21

    We investigate the heterogeneity of electrical conductivity as a new mechanism to stimulate excitable tissues via applied electric fields. In particular, we show that stimulation of axons crossing internal boundaries can occur at boundaries where the electric conductivity of the volume conductor changes abruptly. The effectiveness of this and other stimulation mechanisms was compared by means of models and computer simulations in the context of transcranial magnetic stimulation. While, for a given stimulation intensity, the largest membrane depolarization occurred where an axon terminates or bends sharply in a high electric field region, a slightly smaller membrane depolarization, still sufficient to generate action potentials, also occurred at an internal boundary where the conductivity jumped from 0.143 S m{sup -1} to 0.333 S m{sup -1}, simulating a white-matter-grey-matter interface. Tissue heterogeneity can also give rise to local electric field gradients that are considerably stronger and more focal than those impressed by the stimulation coil and that can affect the membrane potential, albeit to a lesser extent than the two mechanisms mentioned above. Tissue heterogeneity may play an important role in electric and magnetic 'far-field' stimulation.

  5. Olfactory hallucinations elicited by electrical stimulation via subdural electrodes: effects of direct stimulation of olfactory bulb and tract.

    Science.gov (United States)

    Kumar, Gogi; Juhász, Csaba; Sood, Sandeep; Asano, Eishi

    2012-06-01

    In 1954, Penfield and Jasper briefly described that percepts of unpleasant odor were elicited by intraoperative electrical stimulation of the olfactory bulb in patients with epilepsy. Since then, few peer-reviewed studies have reported such phenomena elicited by stimulation mapping via subdural electrodes implanted on the ventral surface of the frontal lobe. Here, we determined what types of olfactory hallucinations could be reproduced by such stimulation in children with focal epilepsy. This study included 16 children (age range: 5 to 17 years) who underwent implantation of subdural electrodes to localize the presumed epileptogenic zone and eloquent areas. Pairs of electrodes were electrically stimulated, and clinical responses were observed. In case a patient reported a perception, she/he was asked to describe its nature. We also described the stimulus parameters to elicit a given symptom. Eleven patients reported a perception of smell in response to electrical stimulation while the remaining five did not. Nine patients perceived an unpleasant smell (like bitterness, smoke, or garbage) while two perceived a pleasant smell (like strawberry or good food). Such olfactory hallucinations were induced by stimulation proximal to the olfactory bulb or tract on either hemisphere but not by that of orbitofrontal gyri lateral to the medial orbital sulci. The range of stimulus parameters employed to elicit olfactory hallucinations was comparable to those for other sensorimotor symptoms. Our systematic study of children with epilepsy replicated stimulation-induced olfactory hallucinations. We failed to provide evidence that a positive olfactory perception could be elicited by conventional stimulation of secondary olfactory cortex alone. Copyright © 2012 Elsevier Inc. All rights reserved.

  6. Stimulating Music: The Pleasures and Dangers of “Electric Music,” 1750–1900

    Science.gov (United States)

    Kennaway, James

    2014-01-01

    Far from being a purely modern idea, the notion of “electric music” was already common in the eighteenth and nineteenth centuries. The shift in thinking about music from cosmic harmony to nervous stimulation made metaphors and speculative theories relating music and electricity irresistible. This essay considers the development of the idea of electric music, looking at its associations with a sexual “body electric.” It will then examine how this conception of music went from being the subject of sympathy to becoming part of a medical critique of music as a dangerous stimulant, with echoes in music criticism and beyond. PMID:24587689

  7. Electrical stimulation of sacral dermatomes in multiple sclerosis patients with neurogenic detrusor overactivity.

    Science.gov (United States)

    Fjorback, M V; Van Rey, F S; Rijkhoff, N J M; Nøhr, M; Petersen, T; Heesakkers, J P

    2007-01-01

    Transcutaneous electrical stimulation of the dorsal penile/clitoral nerve (DPN) has been shown to suppress detrusor contractions in patients with neurogenic detrusor overactivity (NDO). However, the long-term use of surface electrodes in the genital region may not be well tolerated and may introduce hygienic challenges. The aim of this study was to assess whether electrical stimulation of the sacral dermatomes could suppress detrusor contractions in multiple sclerosis (MS) patients with NDO, hereby providing an alternative to DPN stimulation. A total of 14 MS patients (8 M, 6 F) with low bladder capacity (stimulation was applied. In the second and third filling electrical stimulation of either the DPN or sacral dermatomes was applied automatically whenever the detrusor pressure exceeded 10 cmH2O. The control filling showed detrusor overactivity in 12 of the 14 patients. In 10 of the 12 patients one or more detrusor contractions could be suppressed with DPN stimulation. Electrical stimulation of the sacral dermatomes failed to suppress detrusor contractions in all patients. Although therapeutic effects may be present from stimulation of the sacral dermatomes, we were unable to demonstrate any acute effects during urodynamics. For this reason stimulation of the sacral dermatomes is not an option in a system that relies on the acute suppression of a detrusor contraction. Copyright (c) 2007 Wiley-Liss, Inc.

  8. Stimulation parameter optimization for functional electrical stimulation assisted gait in human spinal cord injury using response surface methodology.

    Science.gov (United States)

    Kim, Yongchul; Schmit, Brian D; Youm, Youngil

    2006-06-01

    The aims of this study were to identify the reflex moment induced by flexion withdrawal reflex and to optimize stimulation parameters for restoring swing motion with respect to initial kinematic conditions in human with spinal cord injury. The influence of hip position and passive movement in the reflex moment were tested in six subjects with chronic spinal cord injury. The two-dimensional dynamic models consisted of thigh, shank and foot segments were developed to compute the swing-phase response and the response surface method was also used to optimize stimulation parameters for restoration of gait by functional electrical stimulation. At three different hip positions, significant linear relationship was found between the reflex moment and hip angle (P spinal cord injured patients. From dynamic simulation, we concluded that optimal solutions of pulse amplitude, frequency and duration time of burst for electrical stimulation assisted gait were influenced by initial kinematic conditions at toe-off. The reflex model and the results of this study can be applied to the design and control strategies of neuroprosthetic devices using functional electrical stimulation for spinal cord injured patients.

  9. Direct and crossed effects of somatosensory electrical stimulation on motor learning and neuronal plasticity in humans

    NARCIS (Netherlands)

    Veldman, M. P.; Zijdewind, I.; Solnik, S.; Maffiuletti, N. A.; Berghuis, K. M. M.; Javet, M.; Negyesi, J.; Hortobagyi, T.

    2015-01-01

    Purpose Sensory input can modify voluntary motor function. We examined whether somatosensory electrical stimulation (SES) added to motor practice (MP) could augment motor learning, interlimb transfer, and whether physiological changes in neuronal excitability underlie these changes. Methods

  10. Movement Along the Spine Induced by Transcranial Electrical Stimulation Related Electrode Positioning

    NARCIS (Netherlands)

    Hoebink, Eric A.; Journee, Henricus L.; de Kleuver, Marinus; Berends, Hanneke; Racz, Ilona; van Hal, Chantal

    2016-01-01

    Study Design. A prospective, nonrandomized cohort study. Objective. To describe a technique quantifying movement induced by transcranial electrical stimulation (TES) induced movement in relation to the positioning of electrodes during spinal deformity surgery. Summary of Background Data. TES induced

  11. Neuromuscular electrical stimulation for preventing skeletal-muscle weakness and wasting in critically ill patients

    DEFF Research Database (Denmark)

    Maffiuletti, Nicola A.; Roig, Marc; Karatzanos, Eleftherios

    2013-01-01

    Background: Neuromuscular electrical stimulation (NMES) therapy may be useful in early musculoskeletal rehabilitation during acute critical illness. The objective of this systematic review was to evaluate the effectiveness of NMES for preventing skeletal-muscle weakness and wasting in critically...

  12. Magnetic and electric stimulation to elicit the masseteric exteroceptive suppression period

    DEFF Research Database (Denmark)

    Komiyama, Osamu; Wang, Kelun; Svensson, Peter

    2010-01-01

    OBJECTIVES: The present study compared the perception of electric and magnetic stimuli for reflex appearance threshold (RT) and reflex saturation threshold (RS) of the exteroceptive suppression reflex (ES) in the masseter muscle. METHODS: Twelve healthy males and 12 females (age: 24.2+/-3.2 years...... and RS for the early and late ES (ES1 and ES2, respectively). RESULTS: ES2 had a lower RT and RS compared to ES1 in electric and magnetic stimulation. Significantly lower NRS values at RT and RS were found with painless magnetic stimulation compared to electric stimulation (p...: In contrast to electrical stimulation, both ES1 and ES2 appeared and saturated with painless magnetic stimuli. SIGNIFICANCE: The present results indicate that both ES1 and ES2 have a non-nociceptive origin. Painless magnetic stimuli will be an advantage in ES reflex examinations for various orofacial pain...

  13. Passive reach and grasp with functional electrical stimulation and robotic arm support

    NARCIS (Netherlands)

    Westerveld, Ard J.; Schouten, Alfred C.; Veltink, Peter H.; van der Kooij, Herman

    2014-01-01

    Rehabilitation of arm and hand function is crucial to increase functional independence of stroke subjects. Here, we investigate the technical feasibility of an integrated training system combining robotics and functional electrical stimulation (FES) to support reach and grasp during functional

  14. Referred pain and cutaneous responses from deep tissue electrical pain stimulation in the groin

    DEFF Research Database (Denmark)

    Aasvang, E K; Werner, M U; Kehlet, H

    2015-01-01

    , supporting individual differences in anatomy and sensory processing. Future studies investigating the responses to deep tissue electrical stimulation in persistent postherniotomy pain patients may advance our understanding of underlying pathophysiological mechanisms and strategies for treatment...

  15. Effects of Smoke Exposure and Other Lifestyle Factors on Pain Response to Electrical Stimulation in Women

    Directory of Open Access Journals (Sweden)

    Joy Yenn May Wee

    2008-01-01

    Full Text Available BACKGROUND: A relationship between smoking and development of pain syndromes has been suggested in the literature. The present study examined associations between smoke exposure and other related variables, and pain response to suprathreshold electrical stimulation.

  16. Electrical nerve stimulation as an aid to the placement of a brachial plexus block : clinical communication

    Directory of Open Access Journals (Sweden)

    K.E. Joubert

    2002-07-01

    Full Text Available Most local anaesthetic blocks are placed blindly, based on a sound knowledge of anatomy. Very often the relationship between the site of deposition of local anaesthetic and the nerve to be blocked is unknown. Large motor neurons may be stimulated with the aid of an electrical current. By observing for muscle twitches, through electrical stimulation of the nerve, a needle can be positioned extremely close to the nerve. The accuracy of local anaesthetic blocks can be improved by this technique. By using the lowest possible current a needle could be positioned within 2-5mm of a nerve. The correct duration of stimulation ensures that stimulation of sensory nerves does not occur. The use of electrical nerve stimulation in veterinary medicine is a novel technique that requires further evaluation.

  17. Biophysical Stimuli: A Review of Electrical and Mechanical Stimulation in Hyaline Cartilage.

    Science.gov (United States)

    Vaca-González, Juan J; Guevara, Johana M; Moncayo, Miguel A; Castro-Abril, Hector; Hata, Yoshie; Garzón-Alvarado, Diego A

    2017-09-01

    Objective Hyaline cartilage degenerative pathologies induce morphologic and biomechanical changes resulting in cartilage tissue damage. In pursuit of therapeutic options, electrical and mechanical stimulation have been proposed for improving tissue engineering approaches for cartilage repair. The purpose of this review was to highlight the effect of electrical stimulation and mechanical stimuli in chondrocyte behavior. Design Different information sources and the MEDLINE database were systematically revised to summarize the different contributions for the past 40 years. Results It has been shown that electric stimulation may increase cell proliferation and stimulate the synthesis of molecules associated with the extracellular matrix of the articular cartilage, such as collagen type II, aggrecan and glycosaminoglycans, while mechanical loads trigger anabolic and catabolic responses in chondrocytes. Conclusion The biophysical stimuli can increase cell proliferation and stimulate molecules associated with hyaline cartilage extracellular matrix maintenance.

  18. Transcutaneous electrical stimulation (TES) for treatment of constipation in children.

    Science.gov (United States)

    Ng, Ruey Terng; Lee, Way Seah; Ang, Hak Lee; Teo, Kai Ming; Yik, Yee Ian; Lai, Nai Ming

    2016-11-11

    Childhood constipation is a common problem with substantial health, economic and emotional burdens. Existing therapeutic options, mainly pharmacological, are not consistently effective, and some are associated with adverse effects after prolonged use. Transcutaneous electrical stimulation (TES), a non-pharmacological approach, is postulated to facilitate bowel movement by modulating the nerves of the large bowel via the application of electrical current transmitted through the abdominal wall. Our main objective was to evaluate the effectiveness and safety of TES when employed to improve bowel function and constipation-related symptoms in children with constipation. We searched MEDLINE (PubMed) (1950 to July 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 7, 2015), EMBASE (1980 to July 2015), the Cochrane IBD Group Specialized Register, trial registries and conference proceedings to identify applicable studies . Randomized controlled trials that assessed any type of TES, administered at home or in a clinical setting, compared to no treatment, a sham TES, other forms of nerve stimulation or any other pharmaceutical or non-pharmaceutical measures used to treat constipation in children were considered for inclusion. Two authors independently assessed studies for inclusion, extracted data and assessed risk of bias of the included studies. We calculated the risk ratio (RR) and corresponding 95% confidence interval (CI) for categorical outcomes data and the mean difference (MD) and corresponding 95% CI for continuous outcomes. We evaluated the overall quality of the evidence supporting the outcomes assessed in this review using the GRADE criteria. One study from Australia including 46 children aged 8 to 18 years was eligible for inclusion. There were multiple reports identified, including one unpublished report, that focused on different outcomes of the same study. The study had unclear risk of selection bias, high risks of

  19. Hypoalgesia in response to transcutaneous electrical nerve stimulation (TENS) depends on stimulation intensity.

    Science.gov (United States)

    Moran, Fidelma; Leonard, Tracey; Hawthorne, Stephanie; Hughes, Ciara M; McCrum-Gardner, Evie; Johnson, Mark I; Rakel, Barbara A; Sluka, Kathleen A; Walsh, Deirdre M

    2011-08-01

    Transcutaneous electrical nerve stimulation (TENS) is an electrophysical modality used for pain management. This study investigated the dose response of different TENS intensities on experimentally induced pressure pain. One hundred and thirty TENS naïve healthy individuals (18-64 years old; 65 males, 65 females) were randomly allocated to 5 groups (n = 26 per group): Strong Non Painful TENS; Sensory Threshold TENS; Below Sensory Threshold TENS; No Current Placebo TENS; and Transient Placebo TENS. Active TENS (80 Hz) was applied to the forearm for 30 minutes. Transient Placebo TENS was applied for 42 seconds after which the current amplitude automatically reset to 0 mA. Pressure pain thresholds (PPT) were recorded from 2 points on the hand and forearm before and after TENS to measure hypoalgesia. There were significant differences between groups at both the hand and forearm (ANOVA; P = .005 and .002). At 30 minutes, there was a significant hypoalgesic effect in the Strong Non Painful TENS group compared to: Below Sensory Threshold TENS, No Current Placebo TENS and Transient Placebo TENS groups (P TENS and No Current Placebo TENS groups at the hand (P = .001). There was no significant difference between Strong Non Painful TENS and Sensory Threshold TENS groups. The area under the curve for the changes in PPT significantly correlated with the current amplitude (r(2) = .33, P = .003). These data therefore show that there is a dose-response effect of TENS with the largest effect occurring with the highest current amplitudes. This study shows a dose response for the intensity of TENS for pain relief with the strongest intensities showing the greatest effect; thus, we suggest that TENS intensity should be titrated to achieve the strongest possible intensity to achieve maximum pain relief. Copyright © 2011 American Pain Society. Published by Elsevier Inc. All rights reserved.

  20. Muscle fiber type specific induction of slow myosin heavy chain 2 gene expression by electrical stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Crew, Jennifer R.; Falzari, Kanakeshwari [Department of Cell Biology and Anatomy, Chicago Medical School, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Road, North Chicago, IL 60064 (United States); DiMario, Joseph X., E-mail: joseph.dimario@rosalindfranklin.edu [Department of Cell Biology and Anatomy, Chicago Medical School, Rosalind Franklin University of Medicine and Science, 3333 Green Bay Road, North Chicago, IL 60064 (United States)

    2010-04-01

    Vertebrate skeletal muscle fiber types are defined by a broad array of differentially expressed contractile and metabolic protein genes. The mechanisms that establish and maintain these different fiber types vary throughout development and with changing functional demand. Chicken skeletal muscle fibers can be generally categorized as fast and fast/slow based on expression of the slow myosin heavy chain 2 (MyHC2) gene in fast/slow muscle fibers. To investigate the cellular and molecular mechanisms that control fiber type formation in secondary or fetal muscle fibers, myoblasts from the fast pectoralis major (PM) and fast/slow medial adductor (MA) muscles were isolated, allowed to differentiate in vitro, and electrically stimulated. MA muscle fibers were induced to express the slow MyHC2 gene by electrical stimulation, whereas PM muscle fibers did not express the slow MyHC2 gene under identical stimulation conditions. However, PM muscle fibers did express the slow MyHC2 gene when electrical stimulation was combined with inhibition of inositol triphosphate receptor (IP3R) activity. Electrical stimulation was sufficient to increase nuclear localization of expressed nuclear-factor-of-activated-T-cells (NFAT), NFAT-mediated transcription, and slow MyHC2 promoter activity in MA muscle fibers. In contrast, both electrical stimulation and inhibitors of IP3R activity were required for these effects in PM muscle fibers. Electrical stimulation also increased levels of peroxisome-proliferator-activated receptor-{gamma} co-activator-1 (PGC-1{alpha}) protein in PM and MA muscle fibers. These results indicate that MA muscle fibers can be induced by electrical stimulation to express the slow MyHC2 gene and that fast PM muscle fibers are refractory to stimulation-induced slow MyHC2 gene expression due to fast PM muscle fiber specific cellular mechanisms involving IP3R activity.

  1. Differential effect of brief electrical stimulation on voltage-gated potassium channels.

    Science.gov (United States)

    Cameron, Morven A; Al Abed, Amr; Buskila, Yossi; Dokos, Socrates; Lovell, Nigel H; Morley, John W

    2017-05-01

    Electrical stimulation of neuronal tissue is a promising strategy to treat a variety of neurological disorders. The mechanism of neuronal activation by external electrical stimulation is governed by voltage-gated ion channels. This stimulus, typically brief in nature, leads to membrane potential depolarization, which increases ion flow across the membrane by increasing the open probability of these voltage-gated channels. In spiking neurons, it is activation of voltage-gated sodium channels (Na V channels) that leads to action potential generation. However, several other types of voltage-gated channels are expressed that also respond to electrical stimulation. In this study, we examine the response of voltage-gated potassium channels (K V channels) to brief electrical stimulation by whole cell patch-clamp electrophysiology and computational modeling. We show that nonspiking amacrine neurons of the retina exhibit a large variety of responses to stimulation, driven by different K V -channel subtypes. Computational modeling reveals substantial differences in the response of specific K V -channel subtypes that is dependent on channel kinetics. This suggests that the expression levels of different K V -channel subtypes in retinal neurons are a crucial predictor of the response that can be obtained. These data expand our knowledge of the mechanisms of neuronal activation and suggest that K V -channel expression is an important determinant of the sensitivity of neurons to electrical stimulation. NEW & NOTEWORTHY This paper describes the response of various voltage-gated potassium channels (K V channels) to brief electrical stimulation, such as is applied during prosthetic electrical stimulation. We show that the pattern of response greatly varies between K V channel subtypes depending on activation and inactivation kinetics of each channel. Our data suggest that problems encountered when artificially stimulating neurons such as cessation in firing at high frequencies, or

  2. A functional electrical stimulation system for human walking inspired by reflexive control principles

    OpenAIRE

    Meng, Lin; Porr, Bernd; Macleod, Catherine A.; Gollee, Henrik

    2017-01-01

    This study presents an innovative multichannel functional electrical stimulation gait-assist system which employs a well-established purely reflexive control algorithm, previously tested in a series of bipedal walking robots. In these robots, ground contact information was used to activate motors in the legs, generating a gait cycle similar to that of humans. Rather than developing a sophisticated closed-loop functional electrical stimulation control strategy for stepping, we have instead uti...

  3. A Novel Method of Two-channel Dual-Pulse Gastric Electrical Stimulation Improves Solid Gastric Emptying in Dogs

    Science.gov (United States)

    Song, Geng-Qing; Hou, Xiaohua; Yang, Bin; Sun, Yan; Qian, Wei; Chen, J D Z

    2009-01-01

    Background Gastric electrical stimulation (GES) is known to improve vomiting with short pulses, normalize dysrhythmia with long pulses, and accelerate gastric emptying with two-channels. The aim of this study was to assess the effects of a new method GES – two-channel GES with dual pulses on gastric emptying of solids as well as gastric dysrhythmia and emetic responses. Methods Seven beagle dogs implanted with 4 pairs of electrodes were studied. A novel method of GES was proposed: two-channel dual-pulse GES in which each stimulus was composed of a short pulse followed with a long pulse, and stimulation was delivered at two different locations. The study was performed to test the effects of this new method of GES on vasopressin-induced delayed gastric emptying of solids, gastric dysrhythmia, and emetic responses. Results 1) Vasopressin induced gastric dysrhythmia and emetic responses, as well as delayed gastric emptying of solids (pchannel, but not one-channel, dual-pulse GES was able to accelerate vasopressin-induced delayed gastric emptying of solids. 3) Both one- and two-channel dual-pulse GES was capable of improving dysrhythmia and emetic responses (pchannel dual-pulse GES is capable of accelerating gastric emptying of solids and improving dysrhythmia and emetic responses induced by vasopressin. This new method of GES may have a potential for gastroparesis. PMID:18154935

  4. A novel method of 2-channel dual-pulse gastric electrical stimulation improves solid gastric emptying in dogs.

    Science.gov (United States)

    Song, Geng-Qing; Hou, Xiaohua; Yang, Bin; Sun, Yan; Qian, Wei; Chen, J D Z

    2008-01-01

    Gastric electrical stimulation (GES) is known to improve vomiting with short pulses, normalize dysrhythmia with long pulses, and accelerate gastric emptying with 2 channels. The aim of this study was to assess the effects of a new method GES, namely, 2-channel GES with dual pulses on gastric emptying of solids as well as gastric dysrhythmia and emetic responses. Seven beagle dogs implanted with 4 pairs of electrodes were studied. A novel method of GES was proposed: 2-channel dual-pulse GES in which each stimulus was composed of a short pulse followed with a long pulse, and stimulation was delivered at 2 different locations. The study was performed to test the effects of this new method of GES on vasopressin-induced delayed gastric emptying of solids, gastric dysrhythmia, and emetic responses. (1) Vasopressin-induced gastric dysrhythmia and emetic responses, as well as delayed gastric emptying of solids (P channel, but not 1-channel, dual-pulse GES was able to accelerate vasopressin-induced delayed gastric emptying of solids. (3) Both 1- and 2-channel dual-pulse GES was capable of improving dysrhythmia and emetic responses (P channel dual-pulse GES is capable of accelerating gastric emptying of solids and improving dysrhythmia and emetic responses induced by vasopressin. This new method of GES may have a potential for gastroparesis.

  5. The Spatial Extent of Epiretinal Electrical Stimulation in the Healthy Mouse Retina

    Directory of Open Access Journals (Sweden)

    Zohreh Hosseinazdeh

    2017-07-01

    Full Text Available Background/Aims: Retinal prostheses use electrical stimulation to restore functional vision to patients blinded by retinitis pigmentosa. A key detail is the spatial pattern of ganglion cells activated by stimulation. Therefore, we characterized the spatial extent of network-mediated electrical activation of retinal ganglion cells (RGCs in the epiretinal monopolar electrode configuration. Methods: Healthy mouse RGC activities were recorded with a micro-electrode array (MEA. The stimuli consisted of monophasic rectangular cathodic voltage pulses and cycling full-field light flashes. Results: Voltage tuning curves exhibited significant hysteresis, reflecting adaptation to electrical stimulation on the time scale of seconds. Responses decreased from 0 to 300 µm, and were also dependent on the strength of stimulation. Applying the Rayleigh criterion to the half-width at half-maximum of the electrical point spread function suggests a visual acuity limit of no better than 20/946. Threshold voltage showed only a modest increase across these distances. Conclusion: The existence of significant hysteresis requires that future investigations of electrical retinal stimulation control for such long-memory adaptation. The spread of electrical activation beyond 200 µm suggests that neighbouring electrodes in epiretinal implants based on indirect stimulation of RGCs may be indiscriminable at interelectrode spacings as large as 400 µm.

  6. Functional electrical stimulation assisted cycling of patients with subacute stroke: kinetic and kinematic analysis.

    Science.gov (United States)

    Szecsi, J; Krewer, C; Müller, F; Straube, A

    2008-10-01

    Cycling is a safe and functionally effective exercise for patients with early post-stroke and poor balance. Such exercise is considered even more effective when functional electrical stimulation is added. Our principal aim was to determine the biomechanically quantifiable parameters of cycling that can be improved in patients with subacute hemiparesis by incorporating functional electrical stimulation. These parameters were defined as objective goals that can be achieved in clinical applications. A secondary aim was to determine whether they could be used to identify subjects who would benefit from such therapy. Using a tricycle testbed, we tested 39 subacute (mean 10.9 weeks post-stroke (SD 5.9)), hemiplegic subjects. During isometric measurements we recorded volitional and electrically evoked crank torques, the latter at maximal tolerable intensity. During ergometric measurements, volitional pedaling was alternated with combined pedaling (volitional supported by stimulation), performed at 30-s intervals. Power, smoothness, and symmetry of cycling were evaluated. Twenty-six percent of the subjects significantly improved the smoothness of their cycling with functional electrical stimulation. Only 8% and 10% significantly increased their power and symmetry, respectively. The improvement in smoothness significantly correlated with the capability of the individual to generate electrical torque (Spearman's rank correlation coefficient=0.66 at P=0.001). The smoothness of cycling was the most sensitive parameter improved by functional electrical stimulation. This improvement depended on the amount of torque evoked, and the torque achieved, in turn, correlated with the tolerated intensity of stimulation.

  7. Motor Skill Acquisition and Retention after Somatosensory Electrical Stimulation in Healthy Humans

    NARCIS (Netherlands)

    Veldman, Menno P; Zijdewind, Inge; Maffiuletti, Nicola A; Hortobágyi, Tibor

    2016-01-01

    Somatosensory electrical stimulation (SES) can increase motor performance, presumably through a modulation of neuronal excitability. Because the effects of SES can outlast the period of stimulation, we examined the possibility that SES can also enhance the retention of motor performance, motor

  8. Modeling binaural responses in the auditory brainstem to electric stimulation of the auditory nerve.

    Science.gov (United States)

    Chung, Yoojin; Delgutte, Bertrand; Colburn, H Steven

    2015-02-01

    Bilateral cochlear implants (CIs) provide improvements in sound localization and speech perception in noise over unilateral CIs. However, the benefits arise mainly from the perception of interaural level differences, while bilateral CI listeners' sensitivity to interaural time difference (ITD) is poorer than normal. To help understand this limitation, a set of ITD-sensitive neural models was developed to study binaural responses to electric stimulation. Our working hypothesis was that central auditory processing is normal with bilateral CIs so that the abnormality in the response to electric stimulation at the level of the auditory nerve fibers (ANFs) is the source of the limited ITD sensitivity. A descriptive model of ANF response to both acoustic and electric stimulation was implemented and used to drive a simplified biophysical model of neurons in the medial superior olive (MSO). The model's ITD sensitivity was found to depend strongly on the specific configurations of membrane and synaptic parameters for different stimulation rates. Specifically, stronger excitatory synaptic inputs and faster membrane responses were required for the model neurons to be ITD-sensitive at high stimulation rates, whereas weaker excitatory synaptic input and slower membrane responses were necessary at low stimulation rates, for both electric and acoustic stimulation. This finding raises the possibility of frequency-dependent differences in neural mechanisms of binaural processing; limitations in ITD sensitivity with bilateral CIs may be due to a mismatch between stimulation rate and cell parameters in ITD-sensitive neurons.

  9. 42 CFR 414.232 - Special payment rules for transcutaneous electrical nerve stimulators (TENS).

    Science.gov (United States)

    2010-10-01

    ... nerve stimulators (TENS). 414.232 Section 414.232 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES... Special payment rules for transcutaneous electrical nerve stimulators (TENS). (a) General payment rule. Except as provided in paragraph (b) of this section, payment for TENS is made on a purchase basis with...

  10. Neural correlates of heterotopic facilitation induced after high frequency electrical stimulation of nociceptive pathways

    NARCIS (Netherlands)

    Broeke, E.N. van den; Heck, C.H. van; Rijn, C.M. van; Wilder-Smith, O.H.G.

    2011-01-01

    Background High frequency electrical stimulation (HFS) of primary nociceptive afferents in humans induce a heightened sensitivity in the surrounding non-stimulated skin area. Several studies suggest that this heterotopic effect is the result of central (spinal) plasticity. The aim of this study is

  11. Neural correlates of heterotopic facilitation induced after high frequency electrical stimulation of nociceptive pathways

    NARCIS (Netherlands)

    Broeke, E.N. van den; Heck, C.H. van; Rijn, C.M. van; Wilder-Smith, O.H.G.

    2011-01-01

    BACKGROUND: High frequency electrical stimulation (HFS) of primary nociceptive afferents in humans induce a heightened sensitivity in the surrounding non-stimulated skin area. Several studies suggest that this heterotopic effect is the result of central (spinal) plasticity. The aim of this study is

  12. Cycle-to-cycle control of swing phase of paraplegic gait induced by surface electrical stimulation

    NARCIS (Netherlands)

    Franken, H.M.; Franken, H.M.; Veltink, Petrus H.; Baardman, G.; Redmeijer, R.A.; Boom, H.B.K.

    1995-01-01

    Parameterised swing phase of gait in paraplegics was obtained using surface electrical stimulation of the hip flexors, hamstrings and quadriceps; the hip flexors were stimulated to obtain a desired hip angle range, the hamstrings to provide foot clearance in the forward swing, and the quadriceps to

  13. Modification of behavioral responses induced by electrical stimulation of the ventral tegmental area in rats.

    Science.gov (United States)

    Watanabe, T; Morimoto, K; Nakamura, M; Suwaki, H

    1998-06-01

    To investigate the role of the ventral tegmental area (VTA), a source of the mesolimbic dopaminergic pathway, in paranoid psychosis, a detailed analysis of the behavioral responses induced by electrical stimulation of the VTA was made. Abnormal behavior induced by bilateral high-frequency stimulation of the VTA consisted of two components: forward locomotion and exploration. Similar responses were obtained when the nucleus accumbens (NAC) or prefrontal cortex (PFC) were stimulated. The expression of behavioral responses to stimulation was significantly attenuated by dopamine (DA) receptor or antagonists, such as haloperidol, YM-09151-2 and SCH23390. These results indicate that VTA stimulation causes a transient hyperdopaminergic state in the brain, that resembles psychostimulant-induced abnormal behavior. The effects of chronic administration of methamphetamine (MAP) on the behavioral responses to electrical stimulation of the VAT were also investigated. Although an acute administration of MAP did not affect the behavioral responses to electrical stimulation of the VTA, chronic treatment with MAP (for 2 weeks) caused a long-lasting reduction in the electrical threshold for the induction of abnormal behavior, compared with chronic saline-treated rats. It is suggested that a lasting enhancement in the behavioral response to stimulation of VTA neurons may contribute to the etiology of paranoid schizophrenia and amphetamine psychosis.

  14. Acupuncture with manual and electrical stimulation for labour pain : a longitudinal randomised controlled trial

    OpenAIRE

    Vixner, Linda; Schytt, Erica; Stener-Victorin, Elisabet; Waldenström, Ulla; Pettersson, Hans; Mårtensson, Lena B.

    2014-01-01

    Background: Acupuncture is commonly used to reduce pain during labour despite contradictory results. The aim of this study is to evaluate the effectiveness of acupuncture with manual stimulation and acupuncture with combined manual and electrical stimulation (electro-acupuncture) compared with standard care in reducing labour pain. Our hypothesis was that both acupuncture stimulation techniques were more effective than standard care, and that electro-acupuncture was most effective.  Methods: ...

  15. Control Methods of the Switched Reluctance Motor in Electric Vehicle During Acceleration

    Directory of Open Access Journals (Sweden)

    Fathy El Sayed ABDEL-KADER

    2012-08-01

    Full Text Available In this paper, the equations describing the performance of the electric vehicle are derived. Performance characteristics for each part in the vehicle system are obtained when the vehicle is accelerated under voltage, turn on and turn off angle control. A comparison between the different methods of control is established.

  16. Muscular Strength Gains and Sensory Perception Changes: A Comparison of Electrical and Combined Electrical/Magnetic Stimulation.

    Science.gov (United States)

    1992-04-10

    Electrotherapy 2d ed. Norwalk, CT: Appleton & Lange; 1991:385-399. 18. Cadwell J. Principles of magnetoelectric stimulation. In: Chokroverty S, ed. Magnetic...press). 23. Cummings J. Electrical stimulation of healthy muscle and tissue repair. In: Nelson RM, Currier DP, eds. Clinical Electrotherapy , 2d ed...flow, and and influencing changes. In: Nelson RM, Currier DP, eds. Clinical Electrotherapy , 2d ed. Norwalk, CT: Appleton & Lange;1991:171-199 27

  17. The efficacy of electrical stimulation in lower extremity cutaneous wound healing: A systematic review.

    Science.gov (United States)

    Ashrafi, Mohammed; Alonso-Rasgado, Teresa; Baguneid, Mohamed; Bayat, Ardeshir

    2017-02-01

    Current gold standard lower extremity cutaneous wound management is not always effective. Cutaneous wounds generate a "current of injury" which is directly involved in wound healing processes. Application of exogenous electrical stimulation has been hypothesised to imitate the natural electric current that occurs in cutaneous wounds. The aim of this extensive review was to provide a detailed update on the variety of electrical stimulation modalities used in the management of lower extremity wounds. Several different waveforms and delivery methods of electrical stimulation have been used. Pulsed current appears superior to other electrical modalities available. The majority of studies support the beneficial effects of pulsed current over conservative management of lower extremity cutaneous wounds. Although it appears to have no benefit over causal surgical intervention, it is a treatment option which could be utilised in those patients unsuitable for surgery. Other waveforms and modalities appear promising; however, they still lack large trial data to recommend a firm conclusion with regards to their use. Current studies also vary in quantity, quality and protocol across the different modalities. The ideal electrical stimulation device needs to be non-invasive, portable and cost-effective and provides minimal interference with patients' daily life. Further studies are necessary to establish the ideal electrical stimulation modality, parameters, method of delivery and duration of treatment. The development and implementation of newer devices in the management of acute and chronic wounds provides an exciting direction in the field of electrotherapy. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Transcutaneous electric nerve stimulation (TENS) for cancer pain in adults.

    Science.gov (United States)

    Hurlow, Adam; Bennett, Michael I; Robb, Karen A; Johnson, Mark I; Simpson, Karen H; Oxberry, Stephen G

    2012-03-14

    Cancer-related pain is complex and multi-dimensional but the mainstay of cancer pain management has predominantly used a biomedical approach. There is a need for non-pharmacological and innovative approaches. Transcutaneous Electric Nerve Stimulation (TENS) may have a role in pain management but the effectiveness of TENS is currently unknown. This is an update of the original review published in Issue 3, 2008. The aim of this systematic review was to determine the effectiveness of TENS for cancer-related pain in adults. The initial review searched The Cochrane Library, MEDLINE, EMBASE, CINAHL, PsychINFO, AMED and PEDRO databases in April 2008. We performed an updated search of CENTRAL, MEDLINE, EMBASE, CINAHL and PEDRO databases in November 2011. We included only randomised controlled trials (RCTS) investigating the use of TENS for the management of cancer-related pain in adults. The search strategy identified a further two studies for possible inclusion. One of the review authors screened each abstract using a study eligibility tool. Where eligibility could not be determined, a second author assessed the full paper. One author used a standardised data extraction sheet to collect information on the studies and independently assess the quality of the studies using the validated five-point Oxford Quality Scale. The small sample sizes and differences in patient study populations of the three included studies (two from the original review and a third included in this update) prevented meta-analysis. For the original review the search strategy identified 37 possible published studies; we divided these between two pairs of review authors who decided on study selection; all four review authors discussed and agreed final scores. Only one additional RCT met the eligibility criteria (24 participants) for this updated review. Although this was a feasibility study, not designed to investigate intervention effect, it suggested that TENS may improve bone pain on movement in a

  19. Interaction of transcranial magnetic stimulation and electrical transmastoid stimulation in human subjects

    DEFF Research Database (Denmark)

    Taylor, Janet L; Petersen, Nicolas Caesar; Butler, Jane E

    2002-01-01

    Transcranial magnetic stimulation activates corticospinal neurones directly and transsynaptically and hence, activates motoneurones and results in a response in the muscle. Transmastoid stimulation results in a similar muscle response through activation of axons in the spinal cord. This study......-wave, facilitation still occurred at ISIs of -6 and -5 ms and depression of the paired response at ISIs of 0, 1, 4 and 5 ms. The interaction of the response to transmastoid stimulation with the multiple descending volleys elicited by magnetic stimulation of the cortex is complex. However, depression of the response...

  20. The reinforcing effect of electrical stimulation of the tongue in thirsty rats : brief communication

    NARCIS (Netherlands)

    Slangen, J.L.; Weijmen, J.A.W.M.

    Thirsty rats repeatedly closed the electric circuit of a drinkometer with their tongue in the absence of water. The hypothesis that electrical stimulation of the tongue has reinforcing properties was tested. The results indicate that persistent licking by a thirsty rat is dependent on a current as

  1. Alternating stimulation of synergistic muscles during functional electrical stimulation cycling improves endurance in persons with spinal cord injury.

    Science.gov (United States)

    Decker, M J; Griffin, L; Abraham, L D; Brandt, L

    2010-12-01

    Therapeutic effects of functional electrical stimulation (FES) cycling for persons with spinal cord injury (SCI) are limited by high rates of muscular fatigue. FES-cycling performance limits and surface mechanomyography (MMG) of 12 persons with SCI were compared under two different stimulation protocols of the quadriceps muscles. One strategy used the standard "co-activation" protocol from the manufacturer of the FES cycle which involved intermittent simultaneous activation of the entire quadriceps muscle group for 400 ms. The other strategy was an "alternation" stimulation protocol which involved alternately stimulating the rectus femoris (RF) muscle for 100 ms and the vastus medialis (VM) and vastus lateralis (VL) muscles for 100 ms, with two sets with a 400 ms burst. Thus, during the alternation protocol, each of the muscle groups rested for two 100 ms "off" periods in each 400 ms burst. There was no difference in average cycling cadence (28 RPM) between the two protocols. The alternation stimulation protocol produced longer ride times and longer virtual distances traveled and used lower stimulation intensity levels with no differences in average MMG amplitudes compared to the co-activation protocol. These results demonstrate that FES-cycling performance can be enhanced by a synergistic muscle alternation stimulation strategy. Copyright © 2010 Elsevier Ltd. All rights reserved.

  2. Effects of Electrical Stimulation on Meat Quality of Lamb and Goat Meat

    Directory of Open Access Journals (Sweden)

    Omer Cetin

    2012-01-01

    Full Text Available Effect of various voltage of electrical stimulation (ES on meat quality of lamb and goat was investigated by using a total of 36 animals at 3–5 years old. Constant 50 Hz frequency and 50, 100, and 250 V, 90 sec of ES were administered to 1/2 carcasses and were examined according their textural, physicochemical, and sensorial characteristics. ES decreased the pH values of lamb and goat meat, and accelerated the rigor mortis (<0.05. Additionally, ES enhanced the water activity, water-holding capacity, and drip loss of both animals. Shear force varied between lamb and goat meat, and tenderness was improved depending on voltage range used (<0.001. ES caused difference in instrumental colour (CIE ∗, ∗, ∗ values of lamb and goat meat compared with the control groups (<0.05 during aging period at 4°C. Sensorial characteristics were also improved with various levels of ES treatments. In conclusion, ES had positive effects on meat quality of lamb and goat, in contrast to undesirable consumer preferences.

  3. Modulation of Osteogenesis in MC3T3-E1 Cells by Different Frequency Electrical Stimulation.

    Directory of Open Access Journals (Sweden)

    Yu Wang

    Full Text Available Electrical stimulation (ES is therapeutic to many bone diseases, from promoting fracture regeneration to orthopedic intervention. The application of ES offers substantial therapeutic potential, while optimal ES parameters and the underlying mechanisms responsible for the positive clinical impact are poorly understood. In this study, we assembled an ES cell culture and monitoring device. Mc-3T3-E1 cells were subjected to different frequency to investigate the effect of osteogenesis. Cell proliferation, DNA synthesis, the mRNA levels of osteosis-related genes, the activity of alkaline phosphatase (ALP, and intracellular concentration of Ca2+ were thoroughly evaluated. We found that 100 Hz could up-regulate the mRNA levels of collagen I, collagen II and Runx2. On the contrary, ES could down-regulate the mRNA levels of osteopontin (OPN. ALP activity assay and Fast Blue RR salt stain showed that 100 Hz could accelerate cells differentiation. Compared to the control group, 100 Hz could promote cell proliferation. Furthermore, 1 Hz to 10 Hz could improve calcium deposition in the intracellular matrix. Overall, these results indicate that 100Hz ES exhibits superior potentialities in osteogenesis, which should be beneficial for the clinical applications of ES for the treatment of bone diseases.

  4. Intrusive thoughts elicited by direct electrical stimulation during stereo-electroencephalography

    Directory of Open Access Journals (Sweden)

    Irina Popa

    2016-07-01

    Full Text Available Cortical direct electrical stimulation (DES is a method of brain mapping used during invasive presurgical evaluation of patients with intractable epilepsy. Intellectual auras like intrusive thoughts, also known as forced thinking (FT, have been reported during frontal seizures. However there are few reports on FT obtained during DES in frontal cortex. We report three cases in which we obtained intrusive thoughts while stimulating the dorsolateral prefrontal cortex and the white matter in the prefrontal region. In order to highlight the effective connectivity that might explain this clinical response, we have analyzed cortico-cortical potentials evoked by single pulse electrical stimulation.

  5. Polymerizing Pyrrole Coated Poly (l-lactic acid-co-ε-caprolactone) (PLCL) Conductive Nanofibrous Conduit Combined with Electric Stimulation for Long-Range Peripheral Nerve Regeneration

    OpenAIRE

    Jialin Song; Binbin Sun; Shen Liu; Wei Chen; Yuanzheng Zhang; Chunyang Wang; Xiumei Mo; Junyi Che; Yuanming Ouyang; Weien Yuan; Cunyi Fan

    2016-01-01

    Electrospinning and electric stimulation (ES) are both promising methods to support neuron adhesion and guide extension of neurons for nerve regeneration. Concurrently, all studies focus on either electrospinning for conduits material or ES in vitro study to accelerate nerve regeneration; few work on the combined use of these two strategies or ES in vivo study. Therefore, this study aimed to investigate the abilities of direct current ES through electrospinning conductive polymer composites c...

  6. Cortical somatosensory evoked potentials from lumbosacral dermatomes: airpuff versus electrical stimulation.

    Science.gov (United States)

    Schimsheimer, R J; Boejharat, K R; van der Sluijs, J C; Stijnen, T; Gryz, E

    1995-01-01

    Cortical potentials were elicited by airpuff stimulation of the L5 and S1 dermatome in a group of 24 healthy volunteers. The results were compared with the SEPs obtained by conventional electrical stimulation. Both stimulus modalities produce stable and good reproducible cortical responses of similar waveform. The most stable second negative peak, labeled N2, was used in this study. Mean latencies (in msec) were: N2 L5 air = 67.1 +/- 3.3, N2 L5 electr. = 55.7 +/- 3.7 N2 S1 air = 67.2 +/- 3.9, and N2 S1 electr. = 55.1 +/- 2.9 The maximum R/L difference (mean + 3 SD) was 5.7 msec, 5.9 msec, 7.2 msec and 7.2 msec for respectively N2 L5 air, N2 L5 electrical, N2 S1 air and N2 S1 electrical. Single regression analysis showed a significant influence of height, but not age upon all latencies. Multiple regression analysis with height and age as independent variables showed a significant influence of height and age together upon the latencies of the electrical SEP (both L5 and S1). For the airpuff SEP only height was significant. Gender had no effect on the cortical components. The amplitude of peak N2 after electrical stimulation of the S1 dermatome was significant higher than after airpuff stimulation, 2.9 and 1.7 microvolt respectively. For the L5 dermatome both types of stimuli produced responses of nearly equal amplitude, 2.5 and 2.1 microvolt for electrical and airpuff stimulation respectively. Airpuff SEPs may provide a good alternative for electrical stimulation.

  7. The efficiency of electrical stimulation to counteract the negative effects of β-agonists on meat tenderness of feedlot cattle.

    Science.gov (United States)

    Hope-Jones, M; Strydom, P E; Frylinck, L; Webb, E C

    2010-11-01

    Beta agonists used as growth enhancers are known to affect the aging potential of beef muscle negatively. On the other hand, procedures like electrical stimulation could accelerate rigor and the aging process. In this study, 20 out of 40 young steers received no beta agonist (C), the remaining twenty steers received a beta agonist (zilpaterol hydrochloride) (Z) for the 30 days prior to slaughter followed by 4 days withdrawal. After slaughter carcasses were split, the left side electrically stimulated (ES) and the right side not stimulated (NES). Samples were aged for 3 or 14 days post mortem. Parameters included Warner Bratzler shear force (WBSF), myofibril filament length (MFL), sarcomere length and calpastatin and calpain enzyme activity. Zilpaterol resulted in increased (Peffect of high calpastatin activity on the aging potential of Z loins. ES can therefore be implemented to improve meat tenderness in zilpaterol supplemented steers, although steers without zilpaterol will still have an advantage in final tenderness. Copyright © 2010 The American Meat Science Association. Published by Elsevier Ltd. All rights reserved.

  8. Electrical stimulation on biodegradation of phenol and responses of microbial communities in conductive carriers supported biofilms of the bioelectrochemical reactor.

    Science.gov (United States)

    Ailijiang, Nuerla; Chang, Jiali; Liang, Peng; Li, Peng; Wu, Qing; Zhang, Xiaoyuan; Huang, Xia

    2016-02-01

    Conductive carbon felts (Cf) were used as biofilm carriers in bioelectrochemical reactors to enhance the electrical stimulation on treatment of phenol-containing synthetic wastewater. In batch test, phenol biodegradation was accelerated under an optimum direct current (DC), which was 2mA for Cf biofilm carriers, lower than that for non-conductive white foam carriers. The stimulation effect was consistent with Adenosine Triphosphate contents in biofilms. The long-term operation further demonstrated that a high and stable phenol removal efficiency could be achieved with applied DC of 2mA, and intermittent DC application was better than continuous one, with phenol removal efficiency of over 97%. Although the quantities of whole microbial communities kept at a high level under all conditions, special microorganisms related with genera of Zoogloea and Desulfovibrio were distinctively enriched under intermittent applied DC pattern. This study shows that the electrical stimulation is potentially effective for biofilm reactors treating phenol-containing wastewater. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Electrical stimulation to conductive scaffold promotes axonal regeneration and remyelination in a rat model of large nerve defect.

    Science.gov (United States)

    Huang, Jinghui; Lu, Lei; Zhang, Jianbin; Hu, Xueyu; Zhang, Yongguang; Liang, Wei; Wu, Siyu; Luo, Zhuojing

    2012-01-01

    Electrical stimulation (ES) has been shown to promote nerve regeneration when it was applied to the proximal nerve stump. However, the possible beneficial effect of establishing a local electrical environment between a large nerve defect on nerve regeneration has not been reported in previous studies. The present study attempted to establish a local electrical environment between a large nerve defect, and examined its effect on nerve regeneration and functional recovery. In the present study, a conductive scaffold was constructed and used to bridge a 15 mm sciatic nerve defect in rats, and intermittent ES (3 V, 20 Hz) was applied to the conductive scaffold to establish an electrical environment at the site of nerve defect. Nerve regeneration and functional recovery were examined after nerve injury repair and ES. We found that axonal regeneration and remyelination of the regenerated axons were significantly enhanced by ES which was applied to conductive scaffold. In addition, both motor and sensory functional recovery was significantly improved and muscle atrophy was partially reversed by ES localized at the conductive scaffold. Further investigations showed that the expression of S-100, BDNF (brain-derived neurotrophic factor), P0 and Par-3 was significantly up-regulated by ES at the conductive scaffold. Establishing an electrical environment with ES localized at the conductive scaffold is capable of accelerating nerve regeneration and promoting functional recovery in a 15 mm nerve defect in rats. The findings provide new directions for exploring regenerative approaches to achieve better functional recovery in the treatment of large nerve defect.

  10. Influence of transcutaneous electrical stimulation on heterotopic ossification: an experimental study in Wistar rats

    Directory of Open Access Journals (Sweden)

    T.G.G. Zotz

    2015-01-01

    Full Text Available Heterotopic ossification (HO is a metaplastic biological process in which there is newly formed bone in soft tissues, resulting in joint mobility deficit and pain. Different treatment modalities have been tried to prevent HO development, but there is no consensus on a therapeutic approach. Since electrical stimulation is a widely used resource in physiotherapy practice to stimulate joint mobility, with analgesic and anti-inflammatory effects, its usefulness for HO treatment was investigated. We aimed to identify the influence of electrical stimulation on induced HO in Wistar rats. Thirty-six male rats (350-390 g were used, and all animals were anesthetized for blood sampling before HO induction, to quantify the serum alkaline phosphatase. HO induction was performed by bone marrow implantation in both quadriceps of the animals, which were then divided into 3 groups: control (CG, transcutaneous electrical nerve stimulation (TENS group (TG, and functional electrical stimulation (FES group (FG with 12 rats each. All animals were anesthetized and electrically stimulated twice per week, for 35 days from induction day. After this period, another blood sample was collected and quadriceps muscles were bilaterally removed for histological and calcium analysis and the rats were killed. Calcium levels in muscles showed significantly lower results when comparing TG and FG (P

  11. Electrical stimulation to reduce chronic toe-flexor hypertonicity. A case report.

    Science.gov (United States)

    Fulbright, J S

    1984-04-01

    Electrical stimulation reduces hypertonicity, but the mechanism for the effectiveness is not well understood. In this particular case, electrical stimulation to the toe extensors resulted in inhibition of the toe-flexor hypertonicity. This phenomenon may be explained by Sherrington's theory of reciprocal inhibition. Liberson found that electrical stimulation of an agonist is associated with a concomitant inhibition of the antagonist in the healthy individual. I applied Liberson's findings in my treatment of the patient. By facilitating the toe extensors, and thus inhibiting the toe flexors, toe posturing improved considerably and allowed the patient volitionally to control his toes, which, in turn, improved his foot and toe comfort. Stimulation also allowed the patient to assume a plantigrade and forefoot weight-bearing position to improve his gait. This patient benefitted dramatically from the use of electrical stimulation in inhibiting hypertonicity, and I believe this modality may be helpful in other cases dealing with increased muscle tone. The patient will continue to be observed on a regular basis for reassessment of the long-term effects of electrical stimulation on hypertonicity and on the skin at the electrode sites.

  12. Renewal-process approximation of a stochastic threshold model for electrical neural stimulation.

    Science.gov (United States)

    Bruce, I C; Irlicht, L S; White, M W; O'Leary, S J; Clark, G M

    2000-01-01

    In a recent set of modeling studies we have developed a stochastic threshold model of auditory nerve response to single biphasic electrical pulses (Bruce et al., 1999c) and moderate rate (less than 800 pulses per second) pulse trains (Bruce et al., 1999a). In this article we derive an analytical approximation for the single-pulse model, which is then extended to describe the pulse-train model in the case of evenly timed, uniform pulses. This renewal-process description provides an accurate and computationally efficient model of electrical stimulation of single auditory nerve fibers by a cochlear implant that may be extended to other forms of electrical neural stimulation.

  13. A wearable multi-pad electrode prototype for selective functional electrical stimulation of upper extremities.

    Science.gov (United States)

    Hai-Peng Wang; Ai-Wen Guo; Zheng-Yang Bi; Fei Li; Xiao-Ying Lu; Zhi-Gong Wang

    2017-07-01

    In this paper, a surface multi-pad stimulation electrode with selective characteristics was designed, it was safe to use and easy to mount. Then a wearable and distributed multi-pad functional electrical stimulation (FES) prototype combined with sensing, communication and smart technology was designed, which can achieve a fast, intelligent optimization to determine stimulation electrode sites and comfortable stimulation. In addition, in order to improve the application and convenience of FES in the rehabilitation at clinical and home-setting, an Android application (APP) based on smart phone was designed for running an algorithm of searching optimal stimulation site. The prototype has been validated by performing selective stimulation on one healthy subject, and showed that the FES system can automatically determine the stimulation site.

  14. Chronic effects of low-frequency low-intensity electrical stimulation of stretched human muscle

    Science.gov (United States)

    Shenkman, Boris S.; Lyubaeva, Ekaterina V.; Popov, Daniil V.; Netreba, Aleksey I.; Bravy, Yan R.; Tarakin, Pavel P.; Lemesheva, Yulia S.; Vinogradova, Olga L.

    2007-02-01

    Effects of low-frequency electrical stimulation, which is currently considered to be a possible countermeasure for long-duration spaceflights, with and without stretch were evaluated. Twelve young male volunteers were randomly distributed into two groups. In one group anterior thigh muscles—knee extensors of both legs were stimulated with frequency of 15 Hz for 4.5 wks, six times a week; each session was 6-h long. In the other group, electrical stimulation with the same parameters was applied to stretched knee extensors. Following stimulation the subjects exhibited an increase in fatigue resistance, and in the succinate dehydrogenase activity and a 10% gain in the percentage of muscle fibers with slow myosin heavy chain isoforms. In a stimulated group the peak voluntary strength went down significantly, the CSA of fast muscle fibers in m. quadriceps femoris became slightly less in size (10%). Electrical stimulation of the stretched muscles induced an insignificant decline in their strength and an increase of cross-sectional area of muscle fibers of both types. Thus chronic low-frequency electrical stimulation may be proposed as a candidate countermeasure against muscle strength and mass loss if it is combined with stretch.

  15. Treatment of neurogenic detrusor overactivity in spinal cord injured patients by conditional electrical stimulation.

    Science.gov (United States)

    Hansen, J; Media, S; Nøhr, M; Biering-Sørensen, F; Sinkjaer, T; Rijkhoff, N J M

    2005-06-01

    The feasibility of automatic event driven electrical stimulation of the dorsal penile/clitoral nerve in the treatment of neurogenic detrusor overactivity (NDO) was evaluated in individuals with spinal cord injury. The study included 2 women and 14 men older than 18 years with NDO, bladder capacity below 500 ml and complete or incomplete suprasacral spinal cord injury. Detrusor pressure (Pdet) was recorded during ordinary, natural bladder filling. In a similar subsequent recording Pdet was used to trigger electrical stimulation when pressure exceeded 10 cm H2O. Of the 16 patients enrolled in this study 13 had increased bladder capacity together with a storage pressure decrease as a result of automatic, event driven electrical stimulation. In 2 patients stimulation could not inhibit the first undesired contraction, leakage occurred and finally 1 could not tolerate stimulation. During stimulated filling Pdet never exceeded 55 cm H2O. Thus, storage pressure was sufficiently low to prevent kidney damage. An average bladder capacity increase of 53% was achieved. This study demonstrates the feasibility of automatic, event driven electrical stimulation in the treatment of NDO. Although the setup in this experiment is not suitable in a clinical setting, the treatment modality is promising and it warrants further investigation.

  16. Spinal cord stimulation for electrical storm refractory to conventional medical treatment: an emerging indication?

    Science.gov (United States)

    Walega, David; Rosenow, Joshua M

    2015-04-01

    To observe the effect of thoracic spinal cord stimulation with dual octipolar epidural electrodes on episodes of ventricular tachycardia and ventricular fibrillation in a patient with nonischemic familial cardiomyopathy and severe electrical storm refractory to conventional medical treatment. Following implantation of temporary bilateral octipolar thoracic epidural electrodes and constant low-grade stimulation, episodes of ventricular tachycardia and ventricular fibrillation were eradicated, and a permanent system was surgically implanted uneventfully. Electrical storm ceased thereafter, though ventricular function from progressive cardiomyopathy worsened, requiring heart transplantation several months later. Spinal cord stimulation may play an important therapeutic role in the treatment of refractory electrical storm when conventional medical treatments have failed. The mechanism by which stimulation of the spinal cord confers a therapeutic effect is not completely understood, although direct modulation of sympathetic and parasympathetic tone in the cardiac conduction system is most likely, based on animal models of ischemia-induced ventricular tachycardia. © 2014 International Neuromodulation Society.

  17. Effects of sustained electrical stimulation on spasticity assessed by the pendulum test

    Directory of Open Access Journals (Sweden)

    Vargas Luna José L.

    2016-09-01

    Full Text Available Neuromodulation using electrical stimulation is able to enhance motor control of individuals suffering an upper motor neuron disorder. This work examined the effect of sustained electrical stimulation to modify spasticity in the leg muscles. We applied transcutaneous spinal cord stimulation with a pulse rate of 50 Hz for 30 min. The subjects were assessed before and after the intervention using in a pendulum test setup. The motion of the free swinging leg was acquired through video tracking and goniometer measurements. The quantification was done through the R2n index which shows consistency identifying the spasticity levels. In all incomplete SCI subjects having severe spasticity, the results show that electrical stimulation is effective to modify the increased muscle tone.

  18. Electrical Stimulation of the Upper Limb in Stroke: Stimulation of the Extensors of the Hand vs. Alternate Stimulation of Flexors and Extensors

    NARCIS (Netherlands)

    de Kroon, J.R.; IJzerman, Maarten Joost; Lankhorst, G.J.; Zilvold, G.

    2004-01-01

    Objective: To investigate whether there is a difference in functional improvement in the affected arm of chronic stroke patients when comparing two methods of electrical stimulation. Design: Explanatory trial in which 30 chronic stroke patients with impaired arm function were randomly allocated to

  19. Platelet activation using electric pulse stimulation: growth factor profile and clinical implications.

    Science.gov (United States)

    Torres, Andrew S; Caiafa, Antonio; Garner, Allen L; Klopman, Steve; LaPlante, Nicole; Morton, Christine; Conway, Kenneth; Michelson, Alan D; Frelinger, Andrew L; Neculaes, V Bogdan

    2014-09-01

    Autologous platelet gel therapy using platelet-rich plasma has emerged as a promising alternative for chronic wound healing, hemostasis, and wound infection control. A critical step for this therapeutic approach is platelet activation, typically performed using bovine thrombin (BT) and calcium chloride. However, exposure of humans to BT can stimulate antibody formation, potentially resulting in severe hemorrhagic or thrombotic complications. Electric pulse stimulation using nanosecond PEFs (pulse electric fields) is an alternative, nonbiochemical platelet activation method, thereby avoiding exposure to xenogeneic thrombin and associated risks. In this study, we identified specific requirements for a clinically relevant activator instrument by dynamically measuring current, voltage, and electric impedance for platelet-rich plasma samples. From these samples, we investigated the profile of growth factors released from human platelets with electric pulse stimulation versus BT, specifically platelet-derived growth factor, transforming growth factor β, and epidermal growth factor, using commercial enzyme-linked immunosorbent assay kits. Electric pulse stimulation triggers growth factor release from platelet α-granules at the same or higher level compared with BT. Electric pulse stimulation is a fast, inexpensive, easy-to-use platelet activation method for autologous platelet gel therapy.

  20. Electrical stimulation of nerve cells using conductive nanofibrous scaffolds for nerve tissue engineering.

    Science.gov (United States)

    Ghasemi-Mobarakeh, Laleh; Prabhakaran, Molamma P; Morshed, Mohammad; Nasr-Esfahani, Mohammad Hossein; Ramakrishna, Seeram

    2009-11-01

    Fabrication of scaffolds with suitable chemical, mechanical, and electrical properties is critical for the success of nerve tissue engineering. Electrical stimulation was directly applied to electrospun conductive nanofibrous scaffolds to enhance the nerve regeneration process. In the present study, electrospun conductive nanofibers were prepared by mixing 10 and 15 wt% doped polyaniline (PANI) with poly (epsilon-caprolactone)/gelatin (PG) (70:30) solution (PANI/PG) by electrospinning. The fiber diameter, pore size, hydrophilicity, tensile properties, conductivity, Fourier transform infrared (FTIR), and X-ray photoelectron spectroscopy spectra of nanofibers were determined, and the in vitro biodegradability of the different nanofibrous scaffolds was also evaluated. Nanofibrous scaffolds containing 15% PANI was found to exhibit the most balanced properties to meet all the required specifications for electrical stimulation for its enhanced conductivity and is used for in vitro culture and electrical stimulation of nerve stem cells. 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay and scanning electron microscopy results showed that conductive nanofibrous scaffolds are suitable substrates for the attachment and proliferation of nerve stem cells. Electrical stimulation through conductive nanofibrous PANI/PG scaffolds showed enhanced cell proliferation and neurite outgrowth compared to the PANI/PG scaffolds that were not subjected to electrical stimulation.

  1. Electro-stimulation of Saccharomyces cerevisiae wine yeasts by Pulsed Electric Field and its effect on fermentation performance

    CERN Document Server

    Mattar, J; Nonus, M; Lebovka, N I; Zakhem, H El; Vorobiev, E

    2013-01-01

    The batch fermentation process, inoculated by pulsed electric field (PEF) treated wine yeasts (S. cerevisiae Actiflore F33), was studied. PEF treatment was applied to the aqueous yeast suspensions (0.12 % wt.) at the electric field strengths of E=100 and 6000 V/cm using the same pulse protocol (number of pulses of n=1000, pulse duration of ti=100 mks, and pulse repetition time of dt=100 ms). Electro-stimulation was confirmed by the observed growth of electrical conductivity of suspensions. The fermentation was running at 30{\\deg}C for 150 hours in an incubator with synchronic agitation. The obtained results clearly evidence the positive impact of PEF treatment on the batch fermentation process. Electro-stimulation resulted in improvement of such process characteristics as mass losses, consumption of soluble matter content ({\\deg}Brix) and synthesis of proteins. It also resulted in a noticeable acceleration of consumption of sugars at the initial stage of fermentation in the lag phase. At the end of the lag ph...

  2. TRANSCUTANEOUS ELECTRICAL NERVE-STIMULATION (TENS) IN RAYNAUDS-PHENOMENON

    NARCIS (Netherlands)

    MULDER, P; DOMPELING, EC; VANSLOCHTERENVANDERBOOR, JC; KUIPERS, WD; SMIT, AJ

    Transcutaneous nerve stimulation (TENS) has been described as resulting in vasodilatation. The effect of 2 Hz TENS of the right hand during forty-five minutes on skin temperature and plethysmography of the third digit of both hands and feet and on transcutaneous oxygen tension (TcpO2) of the right

  3. Experimental electrical stimulation of the bladder using a new device

    DEFF Research Database (Denmark)

    Petersen, T; Christiansen, P; Nielsen, B

    1986-01-01

    electrodes at each ureterovesical junction evoked bladder pressure increase similar to those produced in previous investigations in dogs. Sacral nerve stimulation of S2 evoked bladder contraction at a minimal current. Microscopic examination revealed no cellular reactions to the carbon fibers...

  4. Experimental Observation of Direct Particle Acceleration by Stimulated Emission of Radiation

    Science.gov (United States)

    Banna, Samer; Berezovsky, Valery; Schächter, Levi

    2006-09-01

    We report the first experimental evidence for direct particle acceleration by stimulated emission of radiation. In the framework of this proof-of-principle experiment, a 45 MeV electron macrobunch was modulated by a high-power CO2 laser and then injected into an excited CO2 gas mixture. The emerging microbunches experienced a 0.15% relative change in the kinetic energy, in a less than 40 cm long interaction region. According to our experimental results, a fraction of these electrons have gained more than 200 keV each, implying that such an electron has undergone an order of magnitude of 2×106 collisions of the second kind.

  5. Effects of acute selective pudendal nerve electrical stimulation after simulated childbirth injury

    Science.gov (United States)

    Gill, Bradley C.; Dissaranan, Charuspong; Zutshi, Massarat; Balog, Brian M.; Lin, Danli; Damaser, Margot S.

    2013-01-01

    During childbirth, a combinatorial injury occurs and can result in stress urinary incontinence (SUI). Simulated childbirth injury, consisting of vaginal distension (VD) and pudendal nerve crush (PNC), results in slowed recovery of continence, as well as decreased expression of brain-derived neurotrophic factor (BDNF), a regenerative cytokine. Electrical stimulation has been shown to upregulate BDNF in motor neurons and facilitate axon regrowth through the increase of βII-tubulin expression after injury. In this study, female rats underwent selective pudendal nerve motor branch (PNMB) stimulation after simulated childbirth injury or sham injury to determine whether such stimulation affects bladder and anal function after injury and whether the stimulation increases BDNF expression in Onuf's nucleus after injury. Rats received 4 h of VD followed by bilateral PNC and 1 h of subthreshold electrical stimulation of the left PNMB and sham stimulation of the right PNMB. Rats underwent filling cystometry and anal pressure recording before, during, and after the stimulation. Bladder and anal contractile function were partially disrupted after injury. PNMB stimulation temporarily inhibited bladder contraction after injury. Two days and 1 wk after injury, BDNF expression in Onuf's nucleus of the stimulated side was significantly increased compared with the sham-stimulated side, whereas βII-tubulin expression in Onuf's nucleus of the stimulated side was significantly increased only 1 wk after injury. Acute electrical stimulation of the pudendal nerve proximal to the crush site upregulates BDNF and βII-tubulin in Onuf's nucleus after simulated childbirth injury, which could be a potential preventive option for SUI after childbirth injury. PMID:23152293

  6. Electrical stimulation in white oyster mushroom (Pleurotus florida) production

    Science.gov (United States)

    Roshita, I.; Nurfazira, K. M. P.; Fern, C. Shi; Ain, M. S. Nur

    2017-09-01

    White oyster mushroom (Pleurotus florida) is an edible mushroom that gained popularity due to its nutritional values, low production cost and ease of cultivation. There are several research reported on the mushroom fruiting bodies which were actively developed when applying electrical shock treatment. This study was aimed to investigate the effects of different electrical voltages on the growth and yield of white oyster mushroom (Pleurotus florida). Five different electrical voltages had been applied during spawning period which were 6V, 9V, 12V, 15V and mushroom bags without any treatment served as control. Treatment at 6V showed the highest rate for mycelium growth while 15V took the shortest time for fruiting body formation. However, no significant different (P>0.05) among all the treatments was observed for the time taken for the mycelium to fill-up the bag and pinhead emergence. The total fresh weight and percentage of biological efficiency for treatment at 9V showed higher values compared to control. Treatment at 9V also showed the largest pileus diameter and the most firm in the pileus texture. Meanwhile, treatment at 6V showed the highest a* value (redness). In addition, different electrical voltage treatments applied did not show any significant effect on substrate utilization efficiency, colour L* and b* values. In conclusion, among all the electrical treatments applied, 9V could be considered as the best treatment to enhance the yield of white oyster mushroom.

  7. Dynamic impedance model of the skin-electrode interface for transcutaneous electrical stimulation.

    Directory of Open Access Journals (Sweden)

    José Luis Vargas Luna

    Full Text Available Transcutaneous electrical stimulation can depolarize nerve or muscle cells applying impulses through electrodes attached on the skin. For these applications, the electrode-skin impedance is an important factor which influences effectiveness. Various models describe the interface using constant or current-depending resistive-capacitive equivalent circuit. Here, we develop a dynamic impedance model valid for a wide range stimulation intensities. The model considers electroporation and charge-dependent effects to describe the impedance variation, which allows to describe high-charge pulses. The parameters were adjusted based on rectangular, biphasic stimulation pulses generated by a stimulator, providing optionally current or voltage-controlled impulses, and applied through electrodes of different sizes. Both control methods deliver a different electrical field to the tissue, which is constant throughout the impulse duration for current-controlled mode or have a very current peak for voltage-controlled. The results show a predominant dependence in the current intensity in the case of both stimulation techniques that allows to keep a simple model. A verification simulation using the proposed dynamic model shows coefficient of determination of around 0.99 in both stimulation types. The presented method for fitting electrode-skin impedance can be simple extended to other stimulation waveforms and electrode configuration. Therefore, it can be embedded in optimization algorithms for designing electrical stimulation applications even for pulses with high charges and high current spikes.

  8. A Unique Electrical Thermal Stimulation System Comparable to Moxibustion of Subcutaneous Tissue

    Directory of Open Access Journals (Sweden)

    Hyoun-Seok Myoung

    2014-01-01

    Full Text Available Moxibustion strengthens immunity and it is an effective treatment modality, but, depending on the material quantity, shape, and composition, the thermal strength and intensity can be difficult to control, which may cause pain or epidermal burns. To overcome these limitations, a heat stimulating system which is able to control the thermal intensity was developed. The temperature distributions on epidermis, at 5 mm and 10 mm of depth, in rabbit femoral tissue were compared between moxibustion and the electric thermal stimulation system. The stimulation system consists of a high radio frequency dielectric heating equipment (2 MHz frequency, maximum power 200 W, isolation probe, isolation plate, negative pressure generator, and a temperature assessment system. The temperature was modulated by controlling the stimulation pulse duty ratio, repetition number, and output. There were 95% and 91% temperature distribution correlations between moxibustion and the thermal stimulus at 5 mm and 10 mm of depth in tissue, respectively. Moreover, the epidermal temperature in thermal stimulation was lower than that in moxibustion. These results showed that heat loss by the electric thermal stimulation system is less than that by the traditional moxibustion method. Furthermore, the proposed electric thermal stimulation did not cause adverse effects, such as suppuration or blisters, and also provided subcutaneous stimulation comparable to moxibustion.

  9. Modification of electrical pain threshold by voluntary breathing-controlled electrical stimulation (BreEStim in healthy subjects.

    Directory of Open Access Journals (Sweden)

    Shengai Li

    Full Text Available BACKGROUND: Pain has a distinct sensory and affective (i.e., unpleasantness component. BreEStim, during which electrical stimulation is delivered during voluntary breathing, has been shown to selectively reduce the affective component of post-amputation phantom pain. The objective was to examine whether BreEStim increases pain threshold such that subjects could have improved tolerance of sensation of painful stimuli. METHODS: Eleven pain-free healthy subjects (7 males, 4 females participated in the study. All subjects received BreEStim (100 stimuli and conventional electrical stimulation (EStim, 100 stimuli to two acupuncture points (Neiguan and Weiguan of the dominant hand in a random order. The two different treatments were provided at least three days apart. Painful, but tolerable electrical stimuli were delivered randomly during EStim, but were triggered by effortful inhalation during BreEStim. Measurements of tactile sensation threshold, electrical sensation and electrical pain thresholds, thermal (cold sensation, warm sensation, cold pain and heat pain thresholds were recorded from the thenar eminence of both hands. These measurements were taken pre-intervention and 10-min post-intervention. RESULTS: There was no difference in the pre-intervention baseline measurement of all thresholds between BreEStim and EStim. The electrical pain threshold significantly increased after BreEStim (27.5±6.7% for the dominant hand and 28.5±10.8% for the non-dominant hand, respectively. The electrical pain threshold significantly decreased after EStim (9.1±2.8% for the dominant hand and 10.2±4.6% for the non-dominant hand, respectively (F[1, 10] = 30.992, p = .00024. There was no statistically significant change in other thresholds after BreEStim and EStim. The intensity of electrical stimuli was progressively increased, but no difference was found between BreEStim and EStim. CONCLUSION: Voluntary breathing controlled electrical stimulation

  10. MAGNETIC VERSUS ELECTRICAL STIMULATION IN THE INTERPOLATION TWITCH TECHNIQUE OF ELBOW FLEXORS

    Directory of Open Access Journals (Sweden)

    Sofia I. Lampropoulou

    2012-12-01

    Full Text Available The study compared peripheral magnetic with electrical stimulation of the biceps brachii m. (BB in the single pulse Interpolation Twitch Technique (ITT. 14 healthy participants (31±7 years participated in a within-subjects repeated-measures design study. Single, constant-current electrical and magnetic stimuli were delivered over the motor point of BB with supramaximal intensity (20% above maximum at rest and at various levels of voluntary contraction. Force measurements from right elbow isometric flexion and muscle electromyograms (EMG from the BB, the triceps brachii m. (TB and the abductor pollicis brevis m. (APB were obtained. The twitch forces at rest and maximal contractions, the twitch force-voluntary force relationship, the M-waves and the voluntary activation (VA of BB between magnetic and electrical stimulation were compared. The mean amplitude of the twitches evoked at MVC was not significantly different between electrical (0.62 ± 0.49 N and magnetic (0.81 ± 0.49 N stimulation (p > 0.05, and the maximum VA of BB was comparable between electrical (95% and magnetic (93% stimulation (p > 0. 05. No differences (p >0.05 were revealed in the BB M-waves between electrical (13.47 ± 0.49 mV.ms and magnetic (12.61 ± 0.58 mV.ms stimulation. The TB M-waves were also similar (p > 0.05 but electrically evoked APB M-waves were significantly larger than those evoked by magnetic stimulation (p < 0.05. The twitch-voluntary force relationship over the range of MVCs was best described by non-linear functions for both electrical and magnetic stimulation. The electrically evoked resting twitches were consistently larger in amplitude than the magnetically evoked ones (mean difference 3.1 ± 3.34 N, p < 0.05. Reduction of the inter-electrodes distance reduced the twitch amplitude by 6.5 ± 6.2 N (p < 0.05. The fundamental similarities in voluntary activation assessment of BB with peripheral electrical and magnetic stimulation point towards a promising

  11. Synchronization of neuron population subject to steady DC electric field induced by magnetic stimulation.

    Science.gov (United States)

    Yu, Kai; Wang, Jiang; Deng, Bin; Wei, Xile

    2013-06-01

    Electric fields, which are ubiquitous in the context of neurons, are induced either by external electromagnetic fields or by endogenous electric activities. Clinical evidences point out that magnetic stimulation can induce an electric field that modulates rhythmic activity of special brain tissue, which are associated with most brain functions, including normal and pathological physiological mechanisms. Recently, the studies about the relationship between clinical treatment for psychiatric disorders and magnetic stimulation have been investigated extensively. However, further development of these techniques is limited due to the lack of understanding of the underlying mechanisms supporting the interaction between the electric field induced by magnetic stimulus and brain tissue. In this paper, the effects of steady DC electric field induced by magnetic stimulation on the coherence of an interneuronal network are investigated. Different behaviors have been observed in the network with different topologies (i.e., random and small-world network, modular network). It is found that the coherence displays a peak or a plateau when the induced electric field varies between the parameter range we defined. The coherence of the neuronal systems depends extensively on the network structure and parameters. All these parameters play a key role in determining the range for the induced electric field to synchronize network activities. The presented results could have important implications for the scientific theoretical studies regarding the effects of magnetic stimulation on human brain.

  12. Role of Cortical Cell Type and Morphology in Sub- and Suprathreshold Uniform Electric Field Stimulation

    Science.gov (United States)

    Radman, Thomas; Ramos, Raddy L; Brumberg, Joshua C; Bikson, Marom

    2009-01-01

    Background The neocortex is the most common target of sub-dural electrotherapy and non-invasive brain stimulation modalities including transcranial magnetic stimulation (TMS) and transcranial current simulation (TCS). Specific neuronal elements targeted by cortical stimulation are considered to underlie therapeutic effects, but the exact cell-type(s) affected by these methods remains poorly understood. Objective We determined if neuronal morphology or cell type predicted responses to sub- and suprathreshold uniform electric fields. Methods We characterized the effects of sub- and supra-threshold electrical stimulation on identified cortical neurons in vitro. Uniform electric fields were applied to rat motor cortex brain slices, while recording from interneurons and pyramidal cells across cortical layers, using whole cell patch clamp. Neuron morphology was reconstructed following intracellular dialysis of biocytin. Based solely on volume-weighted morphology, we developed a parsimonious model of neuronal soma polarization by sub-threshold electric fields. Results We found that neuronal morphology correlated with somatic sub-threshold polarization. Based on neuronal morphology, we predict layer V pyramidal neuronal soma to be the most sensitive to polarization by optimally oriented sub-threshold fields. Supra-threshold electric field action potential threshold was shown to reflect both direct cell polarization and synaptic (network) activation. Layer V/VI neuron absolute electric field action potential thresholds were lower than Layer II/III pyramidal neurons and interneurons. Compared to somatic current injection, electric fields promoted burst firing and modulated action potential firing times. PMID:20161507

  13. Tissue engineering bioreactor systems for applying physical and electrical stimulations to cells.

    Science.gov (United States)

    Jin, GyuHyun; Yang, Gi-Hoon; Kim, GeunHyung

    2015-05-01

    Bioreactor systems in tissue engineering applications provide various types of stimulation to mimic the tissues in vitro and in vivo. Various bioreactors have been designed to induce high cellular activities, including initial cell attachment, cell growth, and differentiation. Although cell-stimulation processes exert mostly positive effects on cellular responses, in some cases such stimulation can also have a negative effect on cultured cells. In this review, we discuss various types of bioreactor and the positive and negative effects of stimulation (physical, chemical, and electrical) on various cultured cell types. © 2014 Wiley Periodicals, Inc.

  14. Robust neurite extension following exogenous electrical stimulation within single walled carbon nanotube-composite hydrogels.

    Science.gov (United States)

    Koppes, A N; Keating, K W; McGregor, A L; Koppes, R A; Kearns, K R; Ziemba, A M; McKay, C A; Zuidema, J M; Rivet, C J; Gilbert, R J; Thompson, D M

    2016-07-15

    The use of exogenous electrical stimulation to promote nerve regeneration has achieved only limited success. Conditions impeding optimized outgrowth may arise from inadequate stimulus presentation due to differences in injury geometry or signal attenuation. Implantation of an electrically-conductive biomaterial may mitigate this attenuation and provide a more reproducible signal. In this study, a conductive nanofiller (single-walled carbon nanotubes [SWCNT]) was selected as one possible material to manipulate the bulk electrical properties of a collagen type I-10% Matrigel™ composite hydrogel. Neurite outgrowth within hydrogels (SWCNT or nanofiller-free controls) was characterized to determine if: (1) nanofillers influence neurite extension and (2) electrical stimulation of the nanofiller composite hydrogel enhances neurite outgrowth. Increased SWCNT loading (10-100-μg/mL) resulted in greater bulk conductivity (up to 1.7-fold) with no significant changes to elastic modulus. Neurite outgrowth increased 3.3-fold in 20-μg/mL SWCNT loaded biomaterials relative to the nanofiller-free control. Electrical stimulation promoted greater outgrowth (2.9-fold) within SWCNT-free control. The concurrent presentation of electrical stimulation and SWCNT-loaded biomaterials resulted in a 7.0-fold increase in outgrowth relative to the unstimulated, nanofiller-free controls. Local glia residing within the DRG likely contribute, in part, to the observed increases in outgrowth; but it is unknown which specific nanofiller properties influence neurite extension. Characterization of neuronal behavior in model systems, such as those described here, will aid the rational development of biomaterials as well as the appropriate delivery of electrical stimuli to support nerve repair. Novel biomedical devices delivering electrical stimulation are being developed to mitigate symptoms of Parkinson's, treat drug-resistant depression, control movement or enhance verve regeneration. Carbon

  15. An electric stimulation system for electrokinetic particle manipulation in microfluidic devices.

    Science.gov (United States)

    Lopez-de la Fuente, M S; Moncada-Hernandez, H; Perez-Gonzalez, V H; Lapizco-Encinas, B H; Martinez-Chapa, S O

    2013-03-01

    Microfluidic devices have grown significantly in the number of applications. Microfabrication techniques have evolved considerably; however, electric stimulation systems for microdevices have not advanced at the same pace. Electric stimulation of micro-fluidic devices is an important element in particle manipulation research. A flexible stimulation instrument is desired to perform configurable, repeatable, automated, and reliable experiments by allowing users to select the stimulation parameters. The instrument presented here is a configurable and programmable stimulation system for electrokinetic-driven microfluidic devices; it consists of a processor, a memory system, and a user interface to deliver several types of waveforms and stimulation patterns. It has been designed to be a flexible, highly configurable, low power instrument capable of delivering sine, triangle, and sawtooth waveforms with one single frequency or two superimposed frequencies ranging from 0.01 Hz to 40 kHz, and an output voltage of up to 30 Vpp. A specific stimulation pattern can be delivered over a single time period or as a sequence of different signals for different time periods. This stimulation system can be applied as a research tool where manipulation of particles suspended in liquid media is involved, such as biology, medicine, environment, embryology, and genetics. This system has the potential to lead to new schemes for laboratory procedures by allowing application specific and user defined electric stimulation. The development of this device is a step towards portable and programmable instrumentation for electric stimulation on electrokinetic-based microfluidic devices, which are meant to be integrated with lab-on-a-chip devices.

  16. Distributed low-frequency functional electrical stimulation delays muscle fatigue compared to conventional stimulation.

    Science.gov (United States)

    Malesević, Nebojsa M; Popović, Lana Z; Schwirtlich, Laszlo; Popović, Dejan B

    2010-10-01

    We present a low-frequency stimulation method via multi-pad electrodes for delaying muscle fatigue. We compared two protocols for muscle activation of the quadriceps in paraplegics. One protocol involved a large cathode at 30 HZ (HPR, high pulse-rate), and the other involved four smaller cathodes at 16 HZ (LPR, low pulse-rate). The treatment included 30-min daily sessions for 20 days. One leg was treated with the HPR protocol and the other with the LPR protocol. Knee-joint torque was measured before and after therapy to assess the time interval before the knee-joint torque decreased to 70% of the initial value. The HPR therapy provided greater increases in muscle endurance and force in prolonged training. Yet the LPR stimulation produced less muscle fatigue compared to the HPR stimulation. The results suggest that HPR is the favored protocol for training, and LPR is better suited for prolonged stimulation.

  17. Semiconditional Electrical Stimulation of Pudendal Nerve Afferents Stimulation to Manage Neurogenic Detrusor Overactivity in Patients with Spinal Cord Injury

    OpenAIRE

    Lee, Young-Hee; Kim, Jung Moon; Im, Hyung Tae; Lee, Kye-Wook; Kim, Sung Hoon; Hur, Dong Min

    2011-01-01

    Objective To evaluate the effect of semiconditional electrical stimulation of the pudendal nerve afferents for the neurogenic detrusor overactivity in patients with spinal cord injury. Forty patients (36 males, 4 males) with spinal cord injury who had urinary incontinence and frequency, as well as felt bladder contraction with bladder filling sense or autonomic dysreflexic symptom participated in this study. Method Patients with neurogenic detrusor overactivity were subdivided into complete i...

  18. Chronic Spinal Cord Electrical Stimulation Protects Against 6-hydroxydopamine Lesions

    Science.gov (United States)

    Yadav, Amol P.; Fuentes, Romulo; Zhang, Hao; Vinholo, Thais; Wang, Chi-Han; Freire, Marco Aurelio M.; Nicolelis, Miguel A. L.

    2014-01-01

    Although L-dopa continues to be the gold standard for treating motor symptoms of Parkinson's disease (PD), it presents long-term complications. Deep brain stimulation is effective, but only a small percentage of idiopathic PD patients are eligible. Based on results in animal models and a handful of patients, dorsal column stimulation (DCS) has been proposed as a potential therapy for PD. To date, the long-term effects of DCS in animal models have not been quantified. Here, we report that DCS applied twice a week in rats treated with bilateral 6-OHDA striatal infusions led to a significant improvement in symptoms. DCS-treated rats exhibited a higher density of dopaminergic innervation in the striatum and higher neuronal cell count in the substantia nigra pars compacta compared to a control group. These results suggest that DCS has a chronic therapeutical and neuroprotective effect, increasing its potential as a new clinical option for treating PD patients.

  19. Effects of repetition and temperature on Contingent Electrical Stimulation

    DEFF Research Database (Denmark)

    Castrillon, Eduardo E.; Zhou, Xinwen; Svensson, Peter

    ) activity associated with bruxism. Repetition of the electrical stimulus and skin surface temperature (ST) may affect the perception of CES and possibly also the inhibitory EMG effects.Objectives: To determine the effects of stimulus repetition and skin ST on the perception of CES.  Methods: Healthy...

  20. Chronic Electrical Stimulation with a Suprachoroidal Retinal Prosthesis: A Preclinical Safety and Efficacy Study

    Science.gov (United States)

    Nayagam, David A. X.; Williams, Richard A.; Allen, Penelope J.; Shivdasani, Mohit N.; Luu, Chi D.; Salinas-LaRosa, Cesar M.; Finch, Sue; Ayton, Lauren N.; Saunders, Alexia L.; McPhedran, Michelle; McGowan, Ceara; Villalobos, Joel; Fallon, James B.; Wise, Andrew K.; Yeoh, Jonathan; Xu, Jin; Feng, Helen; Millard, Rodney; McWade, Melanie; Thien, Patrick C.; Williams, Chris E.; Shepherd, Robert K.

    2014-01-01

    Purpose To assess the safety and efficacy of chronic electrical stimulation of the retina with a suprachoroidal visual prosthesis. Methods Seven normally-sighted feline subjects were implanted for 96–143 days with a suprachoroidal electrode array and six were chronically stimulated for 70–105 days at levels that activated the visual cortex. Charge balanced, biphasic, current pulses were delivered to platinum electrodes in a monopolar stimulation mode. Retinal integrity/function and the mechanical stability of the implant were assessed monthly using electroretinography (ERG), optical coherence tomography (OCT) and fundus photography. Electrode impedances were measured weekly and electrically-evoked visual cortex potentials (eEVCPs) were measured monthly to verify that chronic stimuli were suprathreshold. At the end of the chronic stimulation period, thresholds were confirmed with multi-unit recordings from the visual cortex. Randomized, blinded histological assessments were performed by two pathologists to compare the stimulated and non-stimulated retina and adjacent tissue. Results All subjects tolerated the surgical and stimulation procedure with no evidence of discomfort or unexpected adverse outcomes. After an initial post-operative settling period, electrode arrays were mechanically stable. Mean electrode impedances were stable between 11–15 kΩ during the implantation period. Visually-evoked ERGs & OCT were normal, and mean eEVCP thresholds did not substantially differ over time. In 81 of 84 electrode-adjacent tissue samples examined, there were no discernible histopathological differences between stimulated and unstimulated tissue. In the remaining three tissue samples there were minor focal fibroblastic and acute inflammatory responses. Conclusions Chronic suprathreshold electrical stimulation of the retina using a suprachoroidal electrode array evoked a minimal tissue response and no adverse clinical or histological findings. Moreover, thresholds and

  1. Epilepsia partialis continua responsive to neocortical electrical stimulation.

    Science.gov (United States)

    Valentin, Antonio; Ughratdar, Ismail; Cheserem, Beverly; Morris, Robert; Selway, Richard; Alarcon, Gonzalo

    2015-08-01

    Epilepsia partialis continua (EPC), defined as a syndrome of continuous focal jerking, is a rare form of focal status epilepticus that usually affects a distal limb, and when prolonged, can produce long-lasting deficits in limb function. Substantial electrophysiologic evidence links the origin of EPC to the motor cortex; thus surgical resection carries the risk of significant handicap. We present two patients with focal, drug-resistant EPC, who were admitted for intracranial video-electroencephalography monitoring to elucidate the location of the epileptogenic focus and identification of eloquent motor cortex with functional mapping. In both cases, the focus resided at or near eloquent motor cortex and therefore precluded resective surgery. Chronic cortical stimulation delivered through subdural strips at the seizure focus (continuous stimulation at 60-130 Hz, 2-3 mA) resulted in >90% reduction in seizures and abolition of the EPC after a follow-up of 22 months in both patients. Following permanent implantation of cortical stimulators, no adverse effects were noted. EPC restarted when intensity was reduced or batteries depleted. Battery replacement restored previous improvement. This two-case report opens up avenues for the treatment of this debilitating condition. Wiley Periodicals, Inc. © 2015 International League Against Epilepsy.

  2. Parasacral transcutaneous electrical nerve stimulation for overactive bladder in constipated children: The role of constipation.

    Science.gov (United States)

    Veiga, Maria Luiza; Costa, Elen Veruska; Portella, Inaah; Nacif, Ananda; Martinelli Braga, Ana Aparecida; Barroso, Ubirajara

    2016-12-01

    Parasacral transcutaneous electrical nerve stimulation (TENS) is an effective method for the treatment of overactive bladder (OAB), and, additionally, it accelerates bowel transit time. Therefore, not only does parasacral transcutaneous electrical nerve stimulation (TENS) improve lower urinary tract symptoms (LUTS), but it also resolves the problem of constipation in a significant number of children. Since TENS has a positive effect on LUTS and on the symptoms of fecal retention, it is possible that its action regarding OAB could be directly associated with the improvement in constipation. In other words, the positive effect of parasacral TENS in OAB would be because constipation was resolved. The objective of this study was to test that hypothesis. To test the hypothesis that the positive effect of parasacral TENS in OAB would be because constipation had improved with this method. In this prospective study, children with OAB alone were submitted to parasacral TENS. The inclusion criteria consisted of children with idiopathic OAB alone The Rome III criteria for children of 4-18 years of age were used to diagnose constipation. All the children were treated with 20 sessions of parasacral TENS applied for 20 min, three times weekly on alternating days (Figure). No instructions were given to the participants with respect to diet, laxatives, or pharmaceutical treatment for constipation throughout the study period. None of the patients used anticholinergics. Standard urotherapy was prescribed. Parasacral TENS improves OAB and constipation. The presence of constipation before treatment was not associated with a poorer prognosis insofar as the resolution of the symptoms of OAB was concerned. Likewise, there was no association between the resolution of constipation with parasacral TENS and the resolution of OAB. There was no statistically significant difference in urinary symptoms between the constipated and nonconstipated children. There was an improvement in urgency

  3. Spatial Mapping in the Rat Olfactory Bulb by Odor and Direct Electrical Stimulation.

    Science.gov (United States)

    Coelho, Daniel H; Costanzo, Richard M

    2016-09-01

    To directly measure the spatial mapping in the olfactory bulb by odor presentation and by direct electrical stimulation. Experimental (animal). University research laboratory. Odor (n = 8) and electrical stimulation (n = 4) of the olfactory bulb in rats were used to demonstrate the spatial mapping of neural responses in the olfactory bulb. Both multiunit responses to odor stimulation and evoked potential responses to localized electrical stimulation were measured in different regions of the olfactory bulb. Responses that were recorded simultaneously from an array of 32 electrodes positioned at different locations within the olfactory bulb were mapped. Results show different spatial patterns of neural activity for different odors (odor maps). Direct stimulation of the olfactory bulb with electrical current pulses from electrodes positioned at different locations was also effective in generating spatial patterns of neural activity. These data suggest that by programming an array of stimulating electrodes, it should be possible to selectively activate different regions of the olfactory bulb, generating unique patterns of neural activity as seen in normal smell. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.

  4. Electrically stimulated osteogenesis on Ti-PPy/PLGA constructs prepared by laser-assisted processes.

    Science.gov (United States)

    Paun, Irina Alexandra; Stokker-Cheregi, Flavian; Luculescu, Catalin Romeo; Acasandrei, Adriana Maria; Ion, Valentin; Zamfirescu, Marian; Mustaciosu, Cosmin Catalin; Mihailescu, Mona; Dinescu, Maria

    2015-10-01

    This work describes a versatile laser-based protocol for fabricating micro-patterned, electrically conductive titanium-polypyrrole/poly(lactic-co-glycolic)acid (Ti-PPy/PLGA) constructs for electrically stimulated (ES) osteogenesis. Ti supports were patterned using fs laser ablation in order to create high spatial resolution microstructures meant to provide mechanical resistance and physical cues for cell growth. Matrix Assisted Pulsed Laser Evaporation (MAPLE) was used to coat the patterned Ti supports with PPy/PLGA layers acting as biocompatible surfaces having chemical and electrical properties suitable for cell differentiation and mineralization. In vitro biological assays on osteoblast-like MG63 cells showed that the constructs maintained cell viability without cytotoxicity. At 24 h after cell seeding, electrical stimulation with currents of 200 μA was applied for 4 h. This treatment was shown to promote earlier onset of osteogenesis. More specifically, the alkaline phosphatase activity of the stimulated cultures reached the maximum before that of the non-stimulated ones, i.e. controls, indicating faster cell differentiation. Moreover, mineralization was found to occur at an earlier stage in the stimulated cultures, as compared to the controls, starting with Day 6 of cell culture. At later stages, calcium levels in the stimulated cultures were higher than those in control samples by about 70%, with Ca/P ratios similar to those of natural bone. In all, the laser-based protocol emerges as an efficient alternative to existing fabrication technologies. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Stimulation of shank muscles during functional electrical stimulation cycling increases ankle excursion in individuals with spinal cord injury.

    Science.gov (United States)

    Fornusek, Ché; Davis, Glen M; Baek, Ilhun

    2012-11-01

    To investigate the effect of shank muscle stimulation on ankle joint excursion during passive and functional electrical stimulation (FES) leg cycling. Within-subject comparisons. Laboratory setting. Well-trained FES cyclists (N=7) with chronic spinal cord injuries. Two experimental sessions were performed on an isokinetic FES cycle ergometer with a pedal boot that allowed the ankle to plantarflex and dorsiflex during cycling. During the first session, the optimal stimulation timings to induce plantarflexion and dorsiflexion were investigated by systematically altering the stimulation angles of the shank muscles (tibialis anterior [TA] and triceps surae [TS]). During the second session, TA and TS stimulation was included with standard FES cycling (quadriceps, hamstrings, and gluteals) for 6 subjects. Ankle, knee, and hip movements were analyzed using 2-dimensional video. The ankle excursions during passive cycling were 19°±6°. TA and TS stimulation increased ankle joint excursion up to 33°±10° and 27°±7°, respectively. Compared with passive cycling, ankle joint excursion was not significantly increased during standard FES cycling (24°±7°). TA and TS stimulation significantly increased the ankle excursion when applied during standard FES cycling (41°±4°). Freeing the ankle joint to rotate during FES cycling was found to be safe. The combination of shank muscle stimulation and repetitive ankle joint movement may be beneficial for improving ankle flexibility and leg conditioning. Further research is required to test and design ankle supports that might maximize the benefits of shank muscle activation. Copyright © 2012 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  6. Pressure changes under the ischial tuberosities during gluteal neuromuscular stimulation in spinal cord injury: a comparison of sacral nerve root stimulation with surface functional electrical stimulation.

    Science.gov (United States)

    Liu, Liang Qin; Ferguson-Pell, Martin

    2015-04-01

    To compare the magnitude of interface pressure changes during gluteal maximus contraction by stimulating sacral nerve roots with surface electrical stimulations in patients with spinal cord injuries (SCIs). Pilot interventional study. Spinal injury research laboratory. Adults (N=18) with suprasacral complete SCI. Sacral nerve root stimulation (SNRS) via a functional magnetic stimulator (FMS) or a sacral anterior root stimulator (SARS) implant; and surface functional electrical stimulation (FES). Interface pressure under the ischial tuberosity (IT) defined as peak pressure, gradient at peak pressure, and average pressure. With optimal FMS, a 29% average reduction of IT peak pressure was achieved during FMS (mean ± SD: 160.1±24.3mmHg at rest vs 114.7±18.0mmHg during FMS, t5=6.3, P=.002). A 30% average reduction of peak pressure during stimulation via an SARS implant (143.2±31.7mmHg at rest vs 98.5±21.5mmHg during SARS, t5=4.4, P=.007) and a 22% average decrease of IT peak pressure during FES stimulation (153.7±34.8mmHg at rest vs 120.5±26.1mmHg during FES, t5=5.3, P=.003) were obtained. In 4 participants who completed both the FMS and FES studies, the percentage of peak pressure reduction with FMS was slightly greater than with FES (mean difference, 7.8%; 95% confidence interval, 1.6%-14.0; P=.04). SNRS or surface FES can induce sufficient gluteus maximus contraction and significantly reduce ischial pressure. SNRS via an SARS implant may be more convenient and efficient for frequently activating the gluteus maximus. Copyright © 2015 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  7. Maximizing muscle force via low-cadence functional electrical stimulation cycling.

    Science.gov (United States)

    Fornusek, Ché; Davis, Glen M

    2004-09-01

    This study investigated the effect of pedal cadence upon torque production, power output and muscle fatigue rates during functional electrical stimulation evoked cycling in spinal cord injured individuals. All subjects had complete thoracic spinal cord injuries T4-T9 (ASIA A) and had been functional electrical stimulation training regularly for at least 6 months. One trial (n = 8) examined a low vs high pedal rate (20 and 50 rev x min(-1)) upon isolated muscle fatigue over 5 minutes. A second trial (n = 9) investigated the effect of cadence (15 vs 50 rev x min(-1)) upon performance during 35-minutes of functional electrical stimulation evoked cycling. Peak torque produced by left quadriceps decayed significantly faster at the higher pedal cadence, indicating a higher rate of muscle fatigue. Functional electrical stimulation cycling over 35 minutes also revealed that peak and average torques were significantly greater at the lower cadence. From 15 minutes onwards, power output was significantly higher at 50 rev x min(-1) FES-cycling, compared with 15 rev x min(-1). The higher muscle forces observed during low cadence functional electrical stimulation cycling should offer improvements over traditional pedalling velocities for training leg strength in individuals with spinal cord injury.

  8. Electric stimulation and decimeter wave therapy improve the recovery of injured sciatic nerves.

    Science.gov (United States)

    Zhao, Feng; He, Wei; Zhang, Yingze; Tian, Dehu; Zhao, Hongfang; Yu, Kunlun; Bai, Jiangbo

    2013-07-25

    Drug treatment, electric stimulation and decimeter wave therapy have been shown to promote the repair and regeneration of the peripheral nerves at the injured site. This study prepared a Mackinnon's model of rat sciatic nerve compression. Electric stimulation was given immediately after neurolysis, and decimeter wave radiation was performed at 1 and 12 weeks post-operation. Histological observation revealed that intraoperative electric stimulation and decimeter wave therapy could improve the local blood circulation of repaired sites, alleviate hypoxia of compressed nerves, and lessen adhesion of compressed nerves, thereby decreasing the formation of new entrapments and enhancing compressed nerve regeneration through an improved microenvironment for regeneration. Immunohistochemical staining results revealed that intraoperative electric stimulation and decimeter wave could promote the expression of S-100 protein. Motor nerve conduction velocity and amplitude, the number and diameter of myelinated nerve fibers, and sciatic functional index were significantly increased in the treated rats. These results verified that intraoperative electric stimulation and decimeter wave therapy contributed to the regeneration and the recovery of the functions in the compressed nerves.

  9. Role of electrical stimulation for rehabilitation and regeneration after spinal cord injury: an overview.

    Science.gov (United States)

    Hamid, Samar; Hayek, Ray

    2008-09-01

    Structural discontinuity in the spinal cord after injury results in a disruption in the impulse conduction resulting in loss of various bodily functions depending upon the level of injury. This article presents a summary of the scientific research employing electrical stimulation as a means for anatomical or functional recovery for patients suffering from spinal cord injury. Electrical stimulation in the form of functional electrical stimulation (FES) can help facilitate and improve upper/lower limb mobility along with other body functions lost due to injury e.g. respiratory, sexual, bladder or bowel functions by applying a controlled electrical stimulus to generate contractions and functional movement in the paralysed muscles. The available rehabilitative techniques based on FES technology and various Food and Drug Administration, USA approved neuroprosthetic devices that are in use are discussed. The second part of the article summarises the experimental work done in the past 2 decades to study the effects of weakly applied direct current fields in promoting regeneration of neurites towards the cathode and the new emerging technique of oscillating field stimulation which has shown to promote bidirectional regeneration in the injured nerve fibres. The present article is not intended to be an exhaustive review but rather a summary aiming to highlight these two applications of electrical stimulation and the degree of anatomical/functional recovery associated with these in the field of spinal cord injury research.

  10. The effect of intra-operative transcutaneous electrical nerve stimulation on posterior neck pain following thyroidectomy.

    Science.gov (United States)

    Park, C; Choi, J B; Lee, Y-S; Chang, H-S; Shin, C S; Kim, S; Han, D W

    2015-04-01

    Posterior neck pain following thyroidectomy is common because full neck extension is required during the procedure. We evaluated the effect of intra-operative transcutaneous electrical nerve stimulation on postoperative neck pain in patients undergoing total thyroidectomy under general anaesthesia. One hundred patients were randomly assigned to one of two groups; 50 patients received transcutaneous electrical nerve stimulation applied to the trapezius muscle and 50 patients acted as controls. Postoperative posterior neck pain and anterior wound pain were evaluated using an 11-point numerical rating scale at 30 min, 6 h, 24 h and 48 h following surgery. The numerical rating scale for posterior neck pain was significantly lower in the transcutaneous electrical nerve stimulation group compared with the control group at all time points (p < 0.05). There were no significant differences in the numerical rating scale for anterior wound pain at any time point. No adverse effects related to transcutaneous electrical nerve stimulation were observed. We conclude that intra-operative transcutaneous electrical nerve stimulation applied to the trapezius muscle reduced posterior neck pain following thyroidectomy. © 2014 The Association of Anaesthetists of Great Britain and Ireland.

  11. Cardiomyocyte behavior on biodegradable polyurethane/gold nanocomposite scaffolds under electrical stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Ganji, Yasaman [Faculty of Biomedical Engineering, Amirkabir University of Technology, 424 Hafez Ave, Tehran (Iran, Islamic Republic of); Institute for Materials Science, Dept. Biocompatible Nanomaterials, University of Kiel, Kaiserstr. 2, D-24143 Kiel (Germany); Li, Qian [Institute for Materials Science, Dept. Biocompatible Nanomaterials, University of Kiel, Kaiserstr. 2, D-24143 Kiel (Germany); Quabius, Elgar Susanne [Dept. of Otorhinolaryngology, Head and Neck Surgery, University of Kiel, Arnold-Heller-Str. 3, Building 27, D-24105 Kiel (Germany); Institute of Immunology, University of Kiel, Arnold-Heller-Str. 3, Building 17, D-24105 Kiel (Germany); Böttner, Martina [Department of Anatomy, University of Kiel, Otto-Hahn-Platz 8, 24118 Kiel (Germany); Selhuber-Unkel, Christine, E-mail: cse@tf.uni-kiel.de [Institute for Materials Science, Dept. Biocompatible Nanomaterials, University of Kiel, Kaiserstr. 2, D-24143 Kiel (Germany); Kasra, Mehran [Faculty of Biomedical Engineering, Amirkabir University of Technology, 424 Hafez Ave, Tehran (Iran, Islamic Republic of)

    2016-02-01

    Following a myocardial infarction (MI), cardiomyocytes are replaced by scar tissue, which decreases ventricular contractile function. Tissue engineering is a promising approach to regenerate such damaged cardiomyocyte tissue. Engineered cardiac patches can be fabricated by seeding a high density of cardiac cells onto a synthetic or natural porous polymer. In this study, nanocomposite scaffolds made of gold nanotubes/nanowires incorporated into biodegradable castor oil-based polyurethane were employed to make micro-porous scaffolds. H9C2 cardiomyocyte cells were cultured on the scaffolds for one day, and electrical stimulation was applied to improve cell communication and interaction in neighboring pores. Cells on scaffolds were examined by fluorescence microscopy and scanning electron microscopy, revealing that the combination of scaffold design and electrical stimulation significantly increased cell confluency of H9C2 cells on the scaffolds. Furthermore, we showed that the gene expression levels of Nkx2.5, atrial natriuretic peptide (ANF) and natriuretic peptide precursor B (NPPB), which are functional genes of the myocardium, were up-regulated by the incorporation of gold nanotubes/nanowires into the polyurethane scaffolds, in particular after electrical stimulation. - Highlights: • Biodegradable polyurethane/gold nanocomposites for cardiomyocyte adhesion are proposed. • The nanocomposite scaffolds are porous and electrical stimulation enhances cell adhesion. • Expression levels of functional myocardium genes were upregulated after electrical stimulation.

  12. Electrical stimulation as an adjunct to spinal fusion: a meta-analysis of controlled clinical trials.

    Science.gov (United States)

    Akai, Masami; Kawashima, Noritaka; Kimura, Toshitaka; Hayashi, Kunihiko

    2002-10-01

    This study was a meta-analysis to examine whether electrical stimulation has a specific effect on spinal fusion. Little evidence exists on the efficacy of electrical stimulation for improving fusion rate of spinal fusion surgery. Using MEDLINE (1966-2000) and EMBASE (1985-1999), a search for articles was carried out using the Medical Subject Headings: (1) electric stimulation or electromagnetic fields, (2) spinal fusion, (3) controlled or clinical trial, and (4) human. Data were extracted from all the hit articles and additionally collected from appropriate journal lists. A total of five randomized controlled trials (RCT) on bones assessing healing of spinal fusion were identified and scored on methodological quality. All the identified studies reported positive findings, but the quality score of each trial showed wide flaws. Because of relatively homogenous subjects who had spine fusion and radiographic assessment from these studies, pooling of the data was able to be performed. Excluding one trial with the lowest score, the combined results of four trials, whose major endpoints were the success rate of the fusion, revealed a statistically significant effect of electrical stimulation with various techniques, but the selected trials still showed wide variation in view of stimulation modalities and treatment protocol. The pooled result of the studies in this review revealed the efficacy of electrical stimulation based on proved methodological quality. As problems on therapeutic modality and protocol remain, there is a further need for improvement in design to constitute acceptable proof and to establish treatment programs that better demonstrate electrical stimulation effects on spinal fusion. Copyright 2002 Wiley-Liss, Inc.

  13. A Study on Duration of Effect of Transcutaneous Electrical Nerve Stimulation Therapy on Whole Saliva Flow.

    Science.gov (United States)

    Bhasin, Neha; Reddy, Sreedevi; Nagarajappa, Anil Kumar; Kakkad, Ankur

    2015-06-01

    Saliva is a complex fluid, whose important role is to maintain the well being of oral cavity. Salivary gland hypofunction or hyposalivation is the condition of having reduced saliva production which leads to the subjective complaint of oral dryness termed xerostomia.(7) Management of xerostomia includes palliative therapy using topical agents or systemic therapy. Electrostimulation to produce saliva was studied in the past and showed moderate promise but never became part of mainstream therapy. Hence, this study was undertaken to evaluate the effect of transcutaneous electrical nerve stimulation (TENS) on whole salivary flow rate in healthy adults and to evaluate how long this effect of TENS lasts on salivary flow. One hundred healthy adult subjects were divided into five age groups with each group containing 20 subjects equally divided into males and females in each group. Unstimulated saliva was collected using a graduated test tube fitted with funnel and quantity was measured. Transcutaneous electrical nerve stimulation unit was activated and stimulated saliva was collected. Saliva was again collected 30 minutes and 24 hours post stimulation. The mean unstimulated whole saliva flow rate for all subjects (n = 100) was 2.60 ml/5 min. During stimulation, it increased to 3.60 ± 0.39 ml/5 min. There was 38.46% increase in salivary flow. Ninety six out of 100 responded positively to TENS therapy. Salivary flow remained increased 30 minutes and 24 hours post stimulation with the values being 3.23 ± 0.41 ml/5 min and 2.69 ± 0.39 ml/5 min respectively. Repeated measures One way analysis of variance (ANOVA) test showed that the difference between these values were statistically significant. Transcutaneous electrical nerve stimulation therapy was effective for stimulation of whole saliva in normal, healthy subjects and its effect retained till 30 minutes and a little up to 24 hours. Transcutaneous electrical nerve stimulation may work best synergistically with other

  14. Application of conductive polymers, scaffolds and electrical stimulation for nerve tissue engineering.

    Science.gov (United States)

    Ghasemi-Mobarakeh, Laleh; Prabhakaran, Molamma P; Morshed, Mohammad; Nasr-Esfahani, Mohammad Hossein; Baharvand, Hossein; Kiani, Sahar; Al-Deyab, Salem S; Ramakrishna, Seeram

    2011-04-01

    Among the numerous attempts to integrate tissue engineering concepts into strategies to repair nearly all parts of the body, neuronal repair stands out. This is partially due to the complexity of the nervous anatomical system, its functioning and the inefficiency of conventional repair approaches, which are based on single components of either biomaterials or cells alone. Electrical stimulation has been shown to enhance the nerve regeneration process and this consequently makes the use of electrically conductive polymers very attractive for the construction of scaffolds for nerve tissue engineering. In this review, by taking into consideration the electrical properties of nerve cells and the effect of electrical stimulation on nerve cells, we discuss the most commonly utilized conductive polymers, polypyrrole (PPy) and polyaniline (PANI), along with their design and modifications, thus making them suitable scaffolds for nerve tissue engineering. Other electrospun, composite, conductive scaffolds, such as PANI/gelatin and PPy/poly(ε-caprolactone), with or without electrical stimulation, are also discussed. Different procedures of electrical stimulation which have been used in tissue engineering, with examples on their specific applications in tissue engineering, are also discussed. Copyright © 2011 John Wiley & Sons, Ltd.

  15. Stimulation of neurite outgrowth using an electrically conducting polymer

    OpenAIRE

    Christine E Schmidt; Shastri, Venkatram R.; Vacanti, Joseph P.; Langer, Robert

    1997-01-01

    Damage to peripheral nerves often cannot be repaired by the juxtaposition of the severed nerve ends. Surgeons have typically used autologous nerve grafts, which have several drawbacks including the need for multiple surgical procedures and loss of function at the donor site. As an alternative, the use of nerve guidance channels to bridge the gap between severed nerve ends is being explored. In this paper, the electrically conductive polymer—oxidized polypyrrole (PP)—has been evaluated for use...

  16. Mussel-Inspired Coatings Directed and Accelerated by an Electric Field.

    Science.gov (United States)

    He, Ai; Zhang, Chao; Lv, Yan; Zhong, Qi-Zhi; Yang, Xi; Xu, Zhi-Kang

    2016-09-01

    Polydopamine-based coatings are fabricated via an electric field-accelerating and -directing codeposition process of polydopamine with charged polymers such as polycations, polyanions, and polyzwitterions. The coatings are uniform and smooth on various substrates, especially on those adhesion-resistant materials including poly(vinylidene fluoride) and poly(tetrafluoroethylene) membranes. Moreover, this electric field-directed deposition method can be applied to facilely prepare Janus membranes with asymmetric chemistry and wettability. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Differential effects of subcutaneous electrical stimulation (SQS) and transcutaneous electrical nerve stimulation (TENS) in rodent models of chronic neuropathic or inflammatory pain.

    Science.gov (United States)

    Vera-Portocarrero, Louis P; Cordero, Toni; Billstrom, Tina; Swearingen, Kim; Wacnik, Paul W; Johanek, Lisa M

    2013-01-01

    Electrical stimulation has been used for many years for the treatment of pain. Present-day research demonstrates that stimulation targets and parameters impact the induction of specific pain-modulating mechanisms. New targets are increasingly being investigated clinically, but the scientific rationale for a particular target is often not well established. This present study compares the behavioral effects of targeting peripheral axons by electrode placement in the subcutaneous space vs. electrode placement on the surface of the skin in a rodent model. Rodent models of inflammatory and neuropathic pain were used to investigate subcutaneous electrical stimulation (SQS) vs. transcutaneous electrical nerve stimulation (TENS). Electrical parameters and relative location of the leads were held constant under each condition. SQS had cumulative antihypersensitivity effects in both inflammatory and neuropathic pain rodent models, with significant inhibition of mechanical hypersensitivity observed on days 3-4 of treatment. In contrast, reduction of thermal hyperalgesia in the inflammatory model was observed during the first four days of treatment with SQS, and reduction of cold allodynia in the neuropathic pain model was seen only on the first day with SQS. TENS was effective in the inflammation model, and in agreement with previous studies, tolerance developed to the antihypersensitivity effects of TENS. With the exception of a reversal of cold hypersensitivity on day 1 of testing, TENS did not reveal significant analgesic effects in the neuropathic pain rodent model. The results presented show that TENS and SQS have different effects that could point to unique biologic mechanisms underlying the analgesic effect of each therapy. Furthermore, this study is the first to demonstrate in an animal model that SQS attenuates neuropathic and inflammatory-induced pain behaviors. © 2013 Medtronic, Inc.

  18. Motor cortex electric stimulation for the treatment of neuropathic pain

    Directory of Open Access Journals (Sweden)

    Walter J. Fagundes-Pereyra

    2010-12-01

    Full Text Available OBJECTIVE: Motor cortex stimulation (MCS is considered to be an effective treatment for chronic neuropathic pain. The aim of the present study was to assess the efficacy of MCS for treating neuropathic pain. METHOD: 27 patients with chronic neuropathic pain were operated. Electrodes were implanted with the use of an stereotactic frame. Electrophysiological evaluations (motor stimulation and somatosensory evoked potentials were performed, with guidance by means of three-dimensional reconstruction of magnetic resonance images of the brain. 10 patients (37% presented central neuropathic pain (post-stroke pain and 17 others (63% presented peripheral neuropathic pain (brachial plexus avulsion, phantom limb pain or trigeminal pain. RESULTS: In 15 patients (57.7% the pain relief was 50% or more; while in ten patients (38.5%, more than 60% of the original pain was relieved. No differences were found in relation to central and peripheral neuropathic pain (p=0.90, pain location (p=0.81, presence of motor deficit (p=0.28 and pain duration (p=0.72. No major complications were observed. CONCLUSION: MCS was efficient for treating patients presenting chronic central or peripheral neuropathic pain.

  19. Electrical stimulation of the primate lateral habenula suppresses saccadic eye movement through a learning mechanism.

    Directory of Open Access Journals (Sweden)

    Masayuki Matsumoto

    Full Text Available The lateral habenula (LHb is a brain structure which represents negative motivational value. Neurons in the LHb are excited by unpleasant events such as reward omission and aversive stimuli, and transmit these signals to midbrain dopamine neurons which are involved in learning and motivation. However, it remains unclear whether these phasic changes in LHb neuronal activity actually influence animal behavior. To answer this question, we artificially activated the LHb by electrical stimulation while monkeys were performing a visually guided saccade task. In one block of trials, saccades to one fixed direction (e.g., right direction were followed by electrical stimulation of the LHb while saccades to the other direction (e.g., left direction were not. The direction-stimulation contingency was reversed in the next block. We found that the post-saccadic stimulation of the LHb increased the latencies of saccades in subsequent trials. Notably, the increase of the latency occurred gradually as the saccade was repeatedly followed by the stimulation, suggesting that the effect of the post-saccadic stimulation was accumulated across trials. LHb stimulation starting before saccades, on the other hand, had no effect on saccade latency. Together with previous studies showing LHb activation by reward omission and aversive stimuli, the present stimulation experiment suggests that LHb activity contributes to learning to suppress actions which lead to unpleasant events.

  20. Non-Invasive Electrical Brain Stimulation Montages for Modulation of Human Motor Function.

    Science.gov (United States)

    Curado, Marco; Fritsch, Brita; Reis, Janine

    2016-02-04

    Non-invasive electrical brain stimulation (NEBS) is used to modulate brain function and behavior, both for research and clinical purposes. In particular, NEBS can be applied transcranially either as direct current stimulation (tDCS) or alternating current stimulation (tACS). These stimulation types exert time-, dose- and in the case of tDCS polarity-specific effects on motor function and skill learning in healthy subjects. Lately, tDCS has been used to augment the therapy of motor disabilities in patients with stroke or movement disorders. This article provides a step-by-step protocol for targeting the primary motor cortex with tDCS and transcranial random noise stimulation (tRNS), a specific form of tACS using an electrical current applied randomly within a pre-defined frequency range. The setup of two different stimulation montages is explained. In both montages the emitting electrode (the anode for tDCS) is placed on the primary motor cortex of interest. For unilateral motor cortex stimulation the receiving electrode is placed on the contralateral forehead while for bilateral motor cortex stimulation the receiving electrode is placed on the opposite primary motor cortex. The advantages and disadvantages of each montage for the modulation of cortical excitability and motor function including learning are discussed, as well as safety, tolerability and blinding aspects.

  1. Effects of exercise and electrical stimulation on lumbar stabilization in asymptomatic subjects: a comparative study.

    Science.gov (United States)

    Bilgin, Sevil; Temucin, Cagrı Mesut; Nurlu, Gulay; Kaya, Derya Ozer; Kose, Nezire; Gunduz, Arzu Guclu

    2013-01-01

    Segmental stabilization training and electrical stimulation are used as a treatment for patients with low back pain. There is limited information on the efficacy of two interventions in the literature. In this study, the efficacy of the two interventions on the multifidus muscle activation and fatigue, segmental stabilization training and electrical stimulation, were examined and compared. Our sample consists of 30 asymptomatic individuals, randomly assigned to one of three groups: the group that was given segmental stabilization training, the group that was given electrical stimulation and the control group that received no treatment. The muscle activity and fatigability of the multifidus were recorded by the surface electromyography before and after the intervention. No difference is detected for any of the multifidus muscle activation and fatigue characteristics either within or between groups. Both techniques did not improve multifidus activation capacity. An effort at submaximal and maximal level affects and increases the activity of multifidus.

  2. Effect of transcutaneous electrical muscle stimulation on muscle volume in patients with septic shock

    DEFF Research Database (Denmark)

    Poulsen, Jesper Brøndum; Møller, Kirsten; Jensen, Claus V

    2011-01-01

    Objective: Intensive care unit admission is associated with muscle wasting and impaired physical function. We investigated the effect of early transcutaneous electrical muscle stimulation on quadriceps muscle volume in patients with septic shock. Design: Randomized interventional study using...... randomization of the quadriceps muscles, transcutaneous electrical muscle stimulation was applied on the intervention side for 7 consecutive days and for 60 mins per day. All patients underwent computed tomographic scans of both thighs immediately before and after the 7-day treatment period. The quadriceps...... sequential organ failure assessment score. Conclusions: We observed a marked decrease in quadriceps volume within the first week of intensive care for septic shock. This loss of muscle mass was unaffected by transcutaneous electrical muscle stimulation applied for 60 mins per day for 7 days....

  3. Direct Electrical Stimulation of the Human Entorhinal Region and Hippocampus Impairs Memory.

    Science.gov (United States)

    Jacobs, Joshua; Miller, Jonathan; Lee, Sang Ah; Coffey, Tom; Watrous, Andrew J; Sperling, Michael R; Sharan, Ashwini; Worrell, Gregory; Berry, Brent; Lega, Bradley; Jobst, Barbara C; Davis, Kathryn; Gross, Robert E; Sheth, Sameer A; Ezzyat, Youssef; Das, Sandhitsu R; Stein, Joel; Gorniak, Richard; Kahana, Michael J; Rizzuto, Daniel S

    2016-12-07

    Deep brain stimulation (DBS) has shown promise for treating a range of brain disorders and neurological conditions. One recent study showed that DBS in the entorhinal region improved the accuracy of human spatial memory. Based on this line of work, we performed a series of experiments to more fully characterize the effects of DBS in the medial temporal lobe on human memory. Neurosurgical patients with implanted electrodes performed spatial and verbal-episodic memory tasks. During the encoding periods of both tasks, subjects received electrical stimulation at 50 Hz. In contrast to earlier work, electrical stimulation impaired memory performance significantly in both spatial and verbal tasks. Stimulation in both the entorhinal region and hippocampus caused decreased memory performance. These findings indicate that the entorhinal region and hippocampus are causally involved in human memory and suggest that refined methods are needed to use DBS in these regions to improve memory. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. Effects of electrical stimulation pattern on quadriceps force production and fatigue.

    Science.gov (United States)

    Deley, Gaelle; Laroche, Davy; Babault, Nicolas

    2014-05-01

    Mixed stimulation programs (MIX) that switch from constant frequency trains (CFT) to variable frequency trains have been proposed to offset the rapid fatigue induced by CFT during electrical stimulation. However, this has never been confirmed with long stimulation patterns, such as those used to evoke functional contractions. The purpose of this study was to test the hypothesis that MIX programs were less fatiguing than CFTs in strength training-like conditions (6-s contractions, 30-min). Thirteen healthy subjects underwent 2 sessions corresponding to MIX and CFT programs. Measurements included maximal voluntary isometric torque and torque evoked by each contraction. There were greater decreases of voluntary and evoked torque (P train types might be a useful strategy to offset rapid fatigue during electrical stimulation sessions with long-duration contractions. Copyright © 2014 Wiley Periodicals, Inc.

  5. A Closed Loop Brain-machine Interface for Epilepsy Control Using Dorsal Column Electrical Stimulation.

    Science.gov (United States)

    Pais-Vieira, Miguel; Yadav, Amol P; Moreira, Derek; Guggenmos, David; Santos, Amílcar; Lebedev, Mikhail; Nicolelis, Miguel A L

    2016-09-08

    Although electrical neurostimulation has been proposed as an alternative treatment for drug-resistant cases of epilepsy, current procedures such as deep brain stimulation, vagus, and trigeminal nerve stimulation are effective only in a fraction of the patients. Here we demonstrate a closed loop brain-machine interface that delivers electrical stimulation to the dorsal column (DCS) of the spinal cord to suppress epileptic seizures. Rats were implanted with cortical recording microelectrodes and spinal cord stimulating electrodes, and then injected with pentylenetetrazole to induce seizures. Seizures were detected in real time from cortical local field potentials, after which DCS was applied. This method decreased seizure episode frequency by 44% and seizure duration by 38%. We argue that the therapeutic effect of DCS is related to modulation of cortical theta waves, and propose that this closed-loop interface has the potential to become an effective and semi-invasive treatment for refractory epilepsy and other neurological disorders.

  6. Semiparametric Identification of Human Arm Dynamics for Flexible Control of a Functional Electrical Stimulation Neuroprosthesis.

    Science.gov (United States)

    Schearer, Eric M; Liao, Yu-Wei; Perreault, Eric J; Tresch, Matthew C; Memberg, William D; Kirsch, Robert F; Lynch, Kevin M

    2016-12-01

    We present a method to identify the dynamics of a human arm controlled by an implanted functional electrical stimulation neuroprosthesis. The method uses Gaussian process regression to predict shoulder and elbow torques given the shoulder and elbow joint positions and velocities and the electrical stimulation inputs to muscles. We compare the accuracy of torque predictions of nonparametric, semiparametric, and parametric model types. The most accurate of the three model types is a semiparametric Gaussian process model that combines the flexibility of a black box function approximator with the generalization power of a parameterized model. The semiparametric model predicted torques during stimulation of multiple muscles with errors less than 20% of the total muscle torque and passive torque needed to drive the arm. The identified model allows us to define an arbitrary reaching trajectory and approximately determine the muscle stimulations required to drive the arm along that trajectory.

  7. [Blink restoration by the functional electrical stimulation in unilateral facial nerve palsy rabbits].

    Science.gov (United States)

    Xue, Yubin; Feng, Guodong; Ding, Xiuyong; Zhao, Yang; Cui, Tingting; Gao, Zhiqiang

    2014-07-01

    Tocompare the effects of different waveforms and parameters of electrical stimulation to elicit a blink, and construct a functional electrical stimulation (FES) system to restore synchronous blink in unilateral facial nerve palsy (FNP). Firstly, twenty-four rabbits were surgically induced unilateral FNP and were divided into three groups, who received square, sine and triangle pulse wareforms, respectirely. Both the healthy and the paralysis eyelids of the rabbits received pulse train stimulation to produce a blink in both eyes. For each rabbit, twenty-seven combinations of frequencies (25 Hz, 50 Hz and 100 Hz) and nine pulse widths (1-9 ms) were stimulated. The threshold amplitude and electric charge to elicit a blink was compared between different waveforms and different parameters. Secondly, a FES system was constructed to treat six surgically induced unilateral FNP rabbit chosen in the twenty-four rabbits, it consisted by an electromyogram (EMG) amplifier module which record the EMG of the healthy muscle, and a stimulator which received the EMG input and output a pulse train stimulation when triggered by the EMG. When the carrier frequency of the pulse train was 25 Hz, it was not able to induce a smooth blink. However, when the carrier frequencies were 50 Hz and 100 Hz, a smooth blink could be induced. The voltage required by 100 Hz was lower than 50 Hz, but it cost more electric charge. The amplitude that square waveforms required was far lower than sine and triangle, but the electric charge between the three waveforms was similar. Synchronous blink could be restored in the six unilateral FNP rabbits with the FES system. To elicit a blink, square pulse train delivered in 50 Hz is a preferable option. The motion of the healthy eyelids as a source of information for stimulation of the paralyzed sides can restore the synchronous blink in unilateral FNP rabbits.

  8. Transcutaneous parasacral electrical neural stimulation in children with primary monosymptomatic enuresis: a prospective randomized clinical trial.

    Science.gov (United States)

    de Oliveira, Liliana Fajardo; de Oliveira, Dayana Maria; da Silva de Paula, Lidyanne Ilídia; de Figueiredo, André Avarese; de Bessa, José; de Sá, Cacilda Andrade; Bastos Netto, José Murillo

    2013-10-01

    Parasacral transcutaneous electrical neural stimulation is widely used to treat hyperactive bladder in children and adults. Its use in nonmonosymptomatic enuresis has demonstrated improvement in number of dry nights. We assessed the effectiveness of parasacral transcutaneous electrical neural stimulation in the treatment of monosymptomatic primary enuresis. This prospective randomized clinical trial included 29 girls and 16 boys older than 6 years with primary monosymptomatic enuresis. Children were randomly divided into 2 groups consisting of controls, who were treated with behavioral therapy, and an experimental group, who were treated with behavioral therapy plus 10 sessions of parasacral transcutaneous electrical neural stimulation. Neural stimulation was performed with the electrodes placed in the sacral region (S2/S3). Sessions always followed the same pattern, with duration of 20 minutes, frequency of 10 Hz, a generated pulse of 700 μs and intensity determined by the sensitivity threshold of the child. Sessions were done 3 times weekly on alternate days. Patients in both groups were followed at 2-week intervals for the first month and then monthly for 6 consecutive months. Rate of wet nights was 77% in controls and 78.3% in the experimental group at onset of treatment (p = 0.82), and 49.5% and 31.2%, respectively, at the end of treatment (p = 0.02). Analyzing the average rate of improvement, there was a significantly greater increase in dry nights in the group undergoing neural stimulation (61.8%) compared to controls (37.3%, p = 0.0038). At the end of treatment percent improvement in children undergoing electrical stimulation had no relation to gender (p = 0.391) or age (p = 0.911). Treatment of primary monosymptomatic enuresis with 10 sessions of parasacral transcutaneous electrical neural stimulation plus behavioral therapy proved to be effective. However, no patient had complete resolution of symptoms. Copyright © 2013 American Urological Association

  9. Establishment of a novel in vitro test setup for electric and magnetic stimulation of human osteoblasts.

    Science.gov (United States)

    Grunert, P C; Jonitz-Heincke, A; Su, Y; Souffrant, R; Hansmann, D; Ewald, H; Krüger, A; Mittelmeier, W; Bader, R

    2014-11-01

    When large defects occur, bone regeneration can be supported by bone grafting and biophysical stimuli like electric and magnetic stimulation (EMS). Clinically established EMS modes are external coils and surgical implants like an electroinductive screw system, which combines a magnetic and electric field, e.g., for the treatment of avascular bone necrosis or pseudarthrosis. For optimization of this implant system, an in vitro test setup was designed to investigate effects of EMS on human osteoblasts on different 3D scaffolds (based on calcium phosphate and collagen). Prior to the cell experiments, numerical simulations of the setup, as well as experimental validation, via measurements of the electric parameters induced by EMS were conducted. Human osteoblasts (3 × 10(5) cells) were seeded onto the scaffolds and cultivated. After 24 h, screw implants (Stryker ASNIS III s-series) were centered in the scaffolds, and EMS was applied (3 × 45 min per day at 20 Hz) for 3 days. Cell viability and collagen type 1 (Col1) synthesis were determined subsequently. Numerical simulation and validation showed an adequate distribution of the electric field within the scaffolds. Experimental measurements of the electric potential revealed only minimal deviation from the simulation. Cell response to stimulation varied with scaffold material and mode of stimulation. EMS-stimulated cells exhibited a significant decrease of metabolic activity in particular on collagen scaffolds. In contrast, the Col1/metabolic activity ratio was significantly increased on collagen and non-sintered calcium phosphate scaffolds after 3 days. Exclusive magnetic stimulation showed similar but nonsignificant tendencies in metabolic activity and Col1 synthesis. The cell tests demonstrate that the new test setup is a valuable tool for in vitro testing and parameter optimization of the clinically used electroinductive screw system. It combines magnetic and electric stimulation, allowing in vitro investigations

  10. The electrical stimulation of carbon nanotubes to provide a cardiomimetic cue to MSCs.

    Science.gov (United States)

    Mooney, Emma; Mackle, Joseph N; Blond, David J-P; O'Cearbhaill, Eoin; Shaw, Georgina; Blau, Werner J; Barry, Frank P; Barron, Valerie; Murphy, J Mary

    2012-09-01

    Once damaged, cardiac muscle has little intrinsic repair capability due to the poor regeneration potential of remaining cardiomyocytes. One method of overcoming this issue is to deliver functional cells to the injured myocardium to promote repair. To address this limitation we sought to test the hypothesis that electroactive carbon nanotubes (CNT) could be employed to direct mesenchymal stem cell (MSC) differentiation towards a cardiomyocyte lineage. Using a two-pronged approach, MSCs exposed to medium containing CNT and MSCs seeded on CNT based polylactic acid scaffolds were electrically stimulated in an electrophysiological bioreactor. After electrical stimulation the cells reoriented perpendicular to the direction of the current and adopted an elongated morphology. Using qPCR, an upregulation in a range of cardiac markers was detected, the greatest of which was observed for cardiac myosin heavy chain (CMHC), where a 40-fold increase was observed for the electrically stimulated cells after 14 days, and a 12-fold increase was observed for the electrically stimulated cells seeded on the PLA scaffolds after 10 days. Differentiation towards a cardioprogenitor cell was more evident from the western blot analysis, where upregulation of Nkx2.5, GATA-4, cardiac troponin t (CTT) and connexin43 (C43) was seen to occur. This was echoed in immunofluorescent staining, where increased levels of CTT, CMHC and C43 protein expression were observed after electrical stimulation for both cells and cell-seeded scaffolds. More interestingly, there was evidence of increased cross talk between the cells as shown by the pattern of C43 staining after electrical stimulation. These results establish a paradigm for nanoscale biomimetic cues that can be readily translated to other electroactive tissue repair applications. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Nanomolar Oxytocin Synergizes with Weak Electrical Afferent Stimulation to Activate the Locomotor CPG of the Rat Spinal Cord In Vitro

    Science.gov (United States)

    Dose, Francesco; Zanon, Patrizia; Coslovich, Tamara; Taccola, Giuliano

    2014-01-01

    Synergizing the effect of afferent fibre stimulation with pharmacological interventions is a desirable goal to trigger spinal locomotor activity, especially after injury. Thus, to better understand the mechanisms to optimize this process, we studied the role of the neuropeptide oxytocin (previously shown to stimulate locomotor networks) on network and motoneuron properties using the isolated neonatal rat spinal cord. On motoneurons oxytocin (1 nM–1 μM) generated sporadic bursts with superimposed firing and dose-dependent depolarization. No desensitization was observed despite repeated applications. Tetrodotoxin completely blocked the effects of oxytocin, demonstrating the network origin of the responses. Recording motoneuron pool activity from lumbar ventral roots showed oxytocin mediated depolarization with synchronous bursts, and depression of reflex responses in a stimulus and peptide-concentration dependent fashion. Disinhibited bursting caused by strychnine and bicuculline was accelerated by oxytocin whose action was blocked by the oxytocin antagonist atosiban. Fictive locomotion appeared when subthreshold concentrations of NMDA plus 5HT were coapplied with oxytocin, an effect prevented after 24 h incubation with the inhibitor of 5HT synthesis, PCPA. When fictive locomotion was fully manifested, oxytocin did not change periodicity, although cycle amplitude became smaller. A novel protocol of electrical stimulation based on noisy waveforms and applied to one dorsal root evoked stereotypic fictive locomotion. Whenever the stimulus intensity was subthreshold, low doses of oxytocin triggered fictive locomotion although oxytocin per se did not affect primary afferent depolarization evoked by dorsal root pulses. Among the several functional targets for the action of oxytocin at lumbar spinal cord level, the present results highlight how small concentrations of this peptide could bring spinal networks to threshold for fictive locomotion in combination with other

  12. Effect of oscillating electrical field stimulation on motor function recovery and myelin regeneration after spinal cord injury in rats.

    Science.gov (United States)

    Tian, Da-Sheng; Jing, Jue-Hua; Qian, Jun; Chen, Lei; Zhu, Bin

    2016-05-01

    [Purpose] The aim of this study was to evaluate the effect of oscillating electrical field stimulation on motor function recovery and myelin regeneration in rats with spinal cord injury. [Subjects and Methods] A rat model of spinal cord injury was constructed by using the Allen weight-drop method. These rats were randomly divided into normal, spinal cord injury, and spinal cord injury + oscillating electrical field stimulation groups. The experimental group received the intervention with oscillating electrical field stimulation, and the control group received the intervention with an electrical field stimulator without oscillating electrical field stimulation. Each group was then randomly divided into seven subgroups according to observation time (1, 2, 4, 6, 8, 10, and 12 weeks). Basso-Beattie-Bresnahan score and inclined plate test score evaluation, motor evoked potential detection, and histological observation were performed. [Results] In the first 2 weeks of oscillating electrical field stimulation, the oscillating electrical field stimulation and inclined plate test scores of spinal cord injury group and spinal cord injury + oscillating electrical field stimulation group were not significantly different. In the fourth week, the scores of the spinal cord injury group were significantly lower than those of the spinal cord injury + oscillating electrical field stimulation group. The motor evoked potential incubation period in the spinal cord injury + oscillating electrical field stimulation group at the various time points was shorter than that in the spinal cord injury group. In the sixth week, the relative area of myelin in the spinal cord injury + oscillating electrical field stimulation group was evidently larger than that in the spinal cord injury group. [Conclusion] Oscillating electrical field stimulation could effectively improve spinal cord conduction function and promote motor function recovery in rats with spinal cord injury, as well as promote myelin

  13. Effects of paired transcutaneous electrical stimulation delivered at single and dual sites over lumbosacral spinal cord.

    Science.gov (United States)

    Sayenko, Dimitry G; Atkinson, Darryn A; Floyd, Terrance C; Gorodnichev, Ruslan M; Moshonkina, Tatiana R; Harkema, Susan J; Edgerton, V Reggie; Gerasimenko, Yury P

    2015-11-16

    It was demonstrated previously that transcutaneous electrical stimulation of multiple sites over the spinal cord is more effective in inducing robust locomotor behavior as compared to the stimulation of single sites alone in both animal and human models. To explore the effects and mechanisms of interactions during multi-site spinal cord stimulation we delivered transcutaneous electrical stimulation to the single or dual locations over the spinal cord corresponding to approximately L2 and S1 segments. Spinally evoked motor potentials in the leg muscles were investigated using single and paired pulses of 1ms duration with conditioning-test intervals (CTIs) of 5 and 50ms. We observed considerable post-stimulation modulatory effects which depended on CTIs, as well as on whether the paired stimuli were delivered at a single or dual locations, the rostro-caudal relation between the conditioning and test stimuli, and on the muscle studied. At CTI-5, the paired stimulation delivered at single locations (L2 or S1) provided strong inhibitory effects, evidenced by the attenuation of the compound responses as compared with responses from either single site. In contrast, during L2-S1 paradigm, the compound responses were potentiated. At CTI-50, the magnitude of inhibition did not differ among paired stimulation paradigms. Our results suggest that electrical stimuli delivered to dual sites over the lumbosacral enlargement in rostral-to-caudal order, may recruit different populations of motor neurons initially through projecting sensory and intraspinal connections and then directly, resulting in potentiation of the compound spinally evoked motor potentials. The interactive and synergistic effects indicate multi-segmental convergence of descending and ascending influences on the neuronal circuitries during electrical spinal cord stimulation. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  14. Effect of early treatment with transcutaneous electrical diaphragmatic stimulation (TEDS) on pulmonary inflammation induced by bleomycin

    OpenAIRE

    Santos,Laisa A.; Silva, Carlos A.; Polacow, Maria L. O.

    2013-01-01

    BACKGROUND : Bleomycin (B) is an antineoplastic drug that has pulmonary fibrosis as a side effect. There are few experimental studies about the effects of physical therapy treatment in this case. OBJECTIVE: The objective was to study rat lungs treated with B and precocious intervention by transcutaneous electrical diaphragmatic stimulation (TEDS). METHOD : Wistar rats were divided into 4 groups (n=5): a control group (C); a stimulated group (TEDS); a group treated with a single dose of...

  15. Effects of sympathetic stimulation on the rhythmical jaw movements produced by electrical stimulation of the cortical masticatory areas of rabbits.

    Science.gov (United States)

    Roatta, S; Windhorst, U; Djupsjöbacka, M; Lytvynenko, S; Passatore, M

    2005-03-01

    The somatomotor and sympathetic nervous systems are intimately linked. One example is the influence of peripheral sympathetic fibers on the discharge characteristics of muscle spindles. Since muscle spindles play important roles in various motor behaviors, including rhythmic movements, the working hypothesis of this research was that changes in sympathetic outflow to muscle spindles can change rhythmic movement patterns. We tested this hypothesis in the masticatory system of rabbits. Rhythmic jaw movements and EMG activity induced by long-lasting electrical cortical stimulation were powerfully modulated by electrical stimulation of the peripheral stump of the cervical sympathetic nerve (CSN). This modulation manifested itself as a consistent and marked reduction in the excursion of the mandibular movements (often preceded by a transient modest enhancement), which could be attributed mainly to corresponding changes in masseter muscle activity. These changes outlasted the duration of CSN stimulation. In some of the cortically evoked rhythmic jaw movements (CRJMs) changes in masticatory frequency were also observed. When the jaw-closing muscles were subjected to repetitive ramp-and-hold force pulses, the CRMJs changed characteristics. Masseter EMG activity was strongly enhanced and digastric EMG slightly decreased. This change was considerably depressed during CSN stimulation. These effects of CSN stimulation are similar in sign and time course to the depression exerted by sympathetic activity on the jaw-closing muscle spindle discharge. It is suggested that the change in proprioceptive information induced by an increase in sympathetic outflow (a) has important implications even under normal conditions for the control of motor function in states of high sympathetic activity, and (b) is one of the mechanisms responsible for motor impairment under certain pathological conditions such as chronic musculoskeletal head-neck disorders, associated with stress conditions.

  16. Fe(III) oxides accelerate microbial nitrate reduction and electricity generation by Klebsiella pneumoniae L17.

    Science.gov (United States)

    Liu, Tongxu; Li, Xiaomin; Zhang, Wei; Hu, Min; Li, Fangbai

    2014-06-01

    Klebsiella pneumoniae L17 is a fermentative bacterium that can reduce iron oxide and generate electricity under anoxic conditions, as previously reported. This study reveals that K. pneumoniae L17 is also capable of dissimilatory nitrate reduction, producing NO2(-), NH4(+), NO and N2O under anoxic conditions. The presence of Fe(III) oxides (i.e., α-FeOOH, γ-FeOOH, α-Fe2O3 and γ-Fe2O3) significantly accelerates the reduction of nitrate and generation of electricity by K. pneumoniae L17, which is similar to a previous report regarding another fermentative bacterium, Bacillus. No significant nitrate reduction was observed upon treatment with Fe(2+) or α-FeOOH+Fe(2+), but a slight facilitation of nitrate reduction and electricity generation was observed upon treatment with L17+Fe(2+). This result suggests that aqueous Fe(II) or mineral-adsorbed Fe(II) cannot reduce nitrate abiotically but that L17 can catalyze the reduction of nitrate and generation of electricity in the presence of Fe(II) (which might exist as cell surface-bound Fe(II)). To rule out the potential effect of Fe(II) produced by L17 during microbial iron reduction, treatments with the addition of TiO2 or Al2O3 instead of Fe(III) oxides also exhibited accelerated microbial nitrate reduction and electricity generation, indicating that cell-mineral sorption did account for the acceleration effect. However, the acceleration caused by Fe(III) oxides is only partially attributed to the cell surface-bound Fe(II) and cell-mineral sorption but may be driven by the iron oxide conduction band-mediated electron transfer from L17 to nitrate or an electrode, as proposed previously. The current study extends the diversity of bacteria of which nitrate reduction and electricity generation can be facilitated by the presence of iron oxides and confirms the positive role of Fe(III) oxides on microbial nitrate reduction and electricity generation by particular fermentative bacteria in anoxic environments. Copyright

  17. Auditory Responses to Electric and Infrared Neural Stimulation of the Rat Cochlear Nucleus

    Science.gov (United States)

    Verma, Rohit; Guex, Amelie A.; Hancock, Kenneth E.; Durakovic, Nedim; McKay, Colette M.; Slama, Michaël C. C.; Brown, M. Christian; Lee, Daniel J.

    2014-01-01

    In an effort to improve the auditory brainstem implant, a prosthesis in which user outcomes are modest, we applied electric and infrared neural stimulation (INS) to the cochlear nucleus in a rat animal model. Electric stimulation evoked regions of neural activation in the inferior colliculus and short-latency, multipeaked auditory brainstem responses (ABRs). Pulsed INS, delivered to the surface of the cochlear nucleus via an optical fiber, evoked broad neural activation in the inferior colliculus. Strongest responses were recorded when the fiber was placed at lateral positions on the cochlear nucleus, close to the temporal bone. INS-evoked ABRs were multipeaked but longer in latency than those for electric stimulation; they resembled the responses to acoustic stimulation. After deafening, responses to electric stimulation persisted, whereas those to INS disappeared, consistent with a reported “optophonic” effect, a laser-induced acoustic artifact. Thus, for deaf individuals who use the auditory brainstem implant, INS alone did not appear promising as a new approach. PMID:24508368

  18. Auditory responses to electric and infrared neural stimulation of the rat cochlear nucleus.

    Science.gov (United States)

    Verma, Rohit U; Guex, Amélie A; Hancock, Kenneth E; Durakovic, Nedim; McKay, Colette M; Slama, Michaël C C; Brown, M Christian; Lee, Daniel J

    2014-04-01

    In an effort to improve the auditory brainstem implant, a prosthesis in which user outcomes are modest, we applied electric and infrared neural stimulation (INS) to the cochlear nucleus in a rat animal model. Electric stimulation evoked regions of neural activation in the inferior colliculus and short-latency, multipeaked auditory brainstem responses (ABRs). Pulsed INS, delivered to the surface of the cochlear nucleus via an optical fiber, evoked broad neural activation in the inferior colliculus. Strongest responses were recorded when the fiber was placed at lateral positions on the cochlear nucleus, close to the temporal bone. INS-evoked ABRs were multipeaked but longer in latency than those for electric stimulation; they resembled the responses to acoustic stimulation. After deafening, responses to electric stimulation persisted, whereas those to INS disappeared, consistent with a reported "optophonic" effect, a laser-induced acoustic artifact. Thus, for deaf individuals who use the auditory brainstem implant, INS alone did not appear promising as a new approach. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Perception of electrical and mechanical stimulation of the skin: implications for electrotactile feedback

    Science.gov (United States)

    Marcus, Patrick L.; Fuglevand, Andrew J.

    2009-12-01

    Spinal cord injury is often accompanied by impaired tactile and proprioceptive sensations. Normally, somatosensensory information derived from such sensations is important in the formation of voluntary motor commands. Therefore, as a preliminary step toward the development of an electrotactile feedback system to restore somatosensation, psychophysical methods were used to characterize perceptual attributes associated with electrical stimulation of the skin on the back of the neck in human subjects. These data were compared to mechanical stimulation of the skin on the back of neck and on the distal pad of the index finger. Spatial acuity of the neck, evaluated using two-point thresholds, was not significantly different for electrical (37 ± 14 mm) or mechanical stimulation (39 ± 10 mm). The exponent (β) of the best fitting power function relating perceived intensity to applied stimulus strength was used to characterize perceptual sensitivity to mechanical and electrical stimuli. For electrical stimuli, both current amplitude-modulated and frequency-modulated trains of pulses were tested. Perceptual sensitivity was significantly greater for current amplitude modulation (β = 1.14 ± 0.37) compared to frequency modulation (β = 0.57 ± 0.24) and mechanical stimulation (0.51 ± 0.12). Finally, based on the data gathered here, we derive a transfer function that could be used in the future to convert mechanical stimuli detected with artificial sensors placed on the fingers into electrotactile signals that evoke perceptions similar to those arising from normal mechanical stimulation of the skin.

  20. TENS (transcutaneous electrical nerve stimulation) for labour pain.

    Science.gov (United States)

    Francis, Richard

    2012-05-01

    Because TENS is applied inconsistently and not always in line with optimal TENS application theory, this may explain why TENS for labour pain appears to be effective in some individuals and not in others. This article reviews TENS theory, advises upon optimal TENS application for labour pain and discusses some of the limitations of TENS research on labour pain. TENS application for labour pain may include TENS applied to either side of the lower spine, set to 200 mus pulse duration and 100 pulses per second. As pain increases, TENS intensity should be increased and as pain decreases, TENS intensity should be reduced to maintain a strong but pain free intensity of stimulation. This application may particularly reduce back pain during labour.

  1. Emerging subspecialties in neurology: deep brain stimulation and electrical neuro-network modulation.

    Science.gov (United States)

    Hassan, Anhar; Okun, Michael S

    2013-01-29

    Deep brain stimulation (DBS) is a surgical therapy that involves the delivery of an electrical current to one or more brain targets. This technology has been rapidly expanding to address movement, neuropsychiatric, and other disorders. The evolution of DBS has created a niche for neurologists, both in the operating room and in the clinic. Since DBS is not always deep, not always brain, and not always simply stimulation, a more accurate term for this field may be electrical neuro-network modulation (ENM). Fellowships will likely in future years evolve their scope to include other technologies, and other nervous system regions beyond typical DBS therapy.

  2. Invasive and transcranial photoacoustic imaging of the vascular response to brain electrical stimulation

    Science.gov (United States)

    Tsytsarev, Vassiliy; Yao, Junjie; Hu, Song; Li, Li; Favazza, Christopher P.; Maslov, Konstantin I.; Wang, Lihong V.

    2010-02-01

    Advances in the brain functional imaging greatly facilitated the understanding of neurovascular coupling. For monitoring of the microvascular response to the brain electrical stimulation in vivo we used optical-resolution photoacoustic microscopy (OR-PAM) through the cranial openings as well as transcranially. Both types of the vascular response, vasoconstriction and vasodilatation, were clearly observed with good spatial and temporal resolution. Obtained results confirm one of the primary points of the neurovascular coupling theory that blood vessels could present vasoconstriction or vasodilatation in response to electrical stimulation, depending on the balance between inhibition and excitation of the different parts of the elements of the neurovascular coupling system.

  3. Identification of key factors in Accelerated Low Water Corrosion through experimental simulation of tidal conditions: influence of stimulated indigenous microbiota.

    Science.gov (United States)

    Marty, Florence; Gueuné, Hervé; Malard, Emilie; Sánchez-Amaya, José M; Sjögren, Lena; Abbas, Ben; Quillet, Laurent; van Loosdrecht, Mark C M; Muyzer, Gerard

    2014-01-01

    Biotic and abiotic factors favoring Accelerated Low Water Corrosion (ALWC) on harbor steel structures remain unclear warranting their study under controlled experimental tidal conditions. Initial stimulation of marine microbial consortia by a pulse of organic matter resulted in localized corrosion and the highest corrosion rates (up to 12-times higher than non-stimulated conditions) in the low water zone, persisting after nine months exposure to natural seawater. Correlations between corrosion severity and the abundance and composition of metabolically active sulfate-reducing bacteria (SRB) indicated the importance and persistence of specific bacterial populations in accelerated corrosion. One phylotype related to the electrogenic SRB Desulfopila corrodens appeared as the major causative agent of the accelerated corrosion. The similarity of bacterial populations related to sulfur and iron cycles, mineral and tuberculation with those identified in ALWC support the relevance of experimental simulation of tidal conditions in the management of steel corrosion exposed to harbor environments.

  4. Electrical Stimulation of the Ventral Tegmental Area Induces Reanimation from General Anesthesia

    Science.gov (United States)

    Solt, Ken; Van Dort, Christa J.; Chemali, Jessica J.; Taylor, Norman E.; Kenny, Jonathan D.; Brown, Emery N.

    2014-01-01

    BACKGROUND Methylphenidate or a D1 dopamine receptor agonist induce reanimation (active emergence) from general anesthesia. We tested whether electrical stimulation of dopaminergic nuclei also induces reanimation from general anesthesia. METHODS In adult rats, a bipolar insulated stainless steel electrode was placed in the ventral tegmental area (VTA, n = 5) or substantia nigra (SN, n = 5). After a minimum 7-day recovery period, the isoflurane dose sufficient to maintain loss of righting was established. Electrical stimulation was initiated and increased in intensity every 3 min to a maximum of 120μA. If stimulation restored the righting reflex, an additional experiment was performed at least 3 days later during continuous propofol anesthesia. Histological analysis was conducted to identify the location of the electrode tip. In separate experiments, stimulation was performed in the prone position during general anesthesia with isoflurane or propofol, and the electroencephalogram was recorded. RESULTS To maintain loss of righting, the dose of isoflurane was 0.9% ± 0.1 vol%, and the target plasma dose of propofol was 4.4 μg/ml ± 1.1 μg/ml (mean ± SD). In all rats with VTA electrodes, electrical stimulation induced a graded arousal response including righting that increased with current intensity. VTA stimulation induced a shift in electroencephalogram peak power from δ (anesthesia with isoflurane or propofol. These results are consistent with the hypothesis that dopamine release by VTA, but not SN, neurons induces reanimation from general anesthesia. PMID:24398816

  5. Spectral distribution of local field potential responses to electrical stimulation of the retina.

    Science.gov (United States)

    Wong, Yan T; Halupka, Kerry; Kameneva, Tatiana; Cloherty, Shaun L; Grayden, David B; Burkitt, Anthony N; Meffin, Hamish; Shivdasani, Mohit N

    2016-06-01

    Different frequency bands of the local field potential (LFP) have been shown to reflect neuronal activity occurring at varying cortical scales. As such, recordings of the LFP may offer a novel way to test the efficacy of neural prostheses and allow improvement of stimulation strategies via neural feedback. Here we use LFP measurements from visual cortex to characterize neural responses to electrical stimulation of the retina. We aim to show that the LFP is a viable signal that contains sufficient information to optimize the performance of sensory neural prostheses. Clinically relevant electrode arrays were implanted in the suprachoroidal space of one eye in four felines. LFPs were simultaneously recorded in response to stimulation of individual electrodes using penetrating microelectrode arrays from the visual cortex. The frequency response of each electrode was extracted using multi-taper spectral analysis and the uniqueness of the responses was determined via a linear decoder. We found that cortical LFPs are reliably modulated by electrical stimulation of the retina and that the responses are spatially localized. We further characterized the spectral distribution of responses, with maximum information being contained in the low and high gamma bands. Finally, we found that LFP responses are unique to a large range of stimulus parameters (∼40) with a maximum conveyable information rate of 6.1 bits. These results show that the LFP can be used to validate responses to electrical stimulation of the retina and we provide the first steps towards using these responses to provide more efficacious stimulation strategies.

  6. Can preoperative electrical nociceptive stimulation predict acute pain after groin herniotomy?

    DEFF Research Database (Denmark)

    Aasvang, Eske Kvanner; Hansen, J.B.; Kehlet, H.

    2008-01-01

    recently been shown to correlate to acute postoperative pain after cesarean section, but the findings have not been confirmed in larger studies or other procedures. Preoperative electrical pain detection threshold and pain tolerance were assessed in patients undergoing a primary unilateral groin hernia...... repair. The correlation between the pain data for electrical stimulation was compared with the postoperative pain during the first week in 165 patients, whereof 3 were excluded. Preoperative electrical pain detection threshold and electrical pain tolerance threshold did not correlate to postoperative......Preoperative identification of patients at risk for high-intensity postoperative pain may be used to predict patients at risk for development of a persistent pain state and allocate patients to more intensive specific pain therapy. Preoperative pain threshold to electrocutaneus stimulation has...

  7. Can preoperative electrical nociceptive stimulation predict acute pain after groin herniotomy?

    DEFF Research Database (Denmark)

    Aasvang, Eske Kvanner; Hansen, Jeanette Birch; Kehlet, Henrik

    2008-01-01

    UNLABELLED: Preoperative identification of patients at risk for high-intensity postoperative pain may be used to predict patients at risk for development of a persistent pain state and allocate patients to more intensive specific pain therapy. Preoperative pain threshold to electrocutaneus...... stimulation has recently been shown to correlate to acute postoperative pain after cesarean section, but the findings have not been confirmed in larger studies or other procedures. Preoperative electrical pain detection threshold and pain tolerance were assessed in patients undergoing a primary unilateral...... groin hernia repair. The correlation between the pain data for electrical stimulation was compared with the postoperative pain during the first week in 165 patients, whereof 3 were excluded. Preoperative electrical pain detection threshold and electrical pain tolerance threshold did not correlate...

  8. An investigation into the induced electric fields from transcranial magnetic stimulation

    Science.gov (United States)

    Hadimani, Ravi; Lee, Erik; Duffy, Walter; Waris, Mohammed; Siddiqui, Waquar; Islam, Faisal; Rajamani, Mahesh; Nathan, Ryan; Jiles, David; David C Jiles Team; Walter Duffy Collaboration

    Transcranial magnetic stimulation (TMS) is a promising tool for noninvasive brain stimulation that has been approved by the FDA for the treatment of major depressive disorder. To stimulate the brain, TMS uses large, transient pulses of magnetic field to induce an electric field in the head. This transient magnetic field is large enough to cause the depolarization of cortical neurons and initiate a synaptic signal transmission. For this study, 50 unique head models were created from MRI images. Previous simulation studies have primarily used a single head model, and thus give a limited image of the induced electric field from TMS. This study uses finite element analysis simulations on 50 unique, heterogeneous head models to better investigate the relationship between TMS and the electric field induced in brain tissues. Results showed a significant variation in the strength of the induced electric field in the brain, which can be reasonably predicted by the distance from the TMS coil to the stimulated brain. Further, it was seen that some models had high electric field intensities in over five times as much brain volume as other models.

  9. Early natural stimulation through environmental enrichment accelerates neuronal development in the mouse dentate gyrus.

    Directory of Open Access Journals (Sweden)

    Na Liu

    Full Text Available The dentate gyrus is the primary afferent into the hippocampal formation, with important functions in learning and memory. Granule cells, the principle neuronal type in the dentate gyrus, are mostly formed postnatally, in a process that continues into adulthood. External stimuli, including environmental enrichment, voluntary exercise and learning, have been shown to significantly accelerate the generation and maturation of dentate granule cells in adult rodents. Whether, and to what extent, such environmental stimuli regulate the development and maturation of dentate granule cells during early postnatal development is largely unknown. Furthermore, whether natural stimuli affect the synaptic properties of granule cells had been investigated neither in newborn neurons of the adult nor during early development. To examine the effect of natural sensory stimulation on the dentate gyrus, we reared newborn mice in an enriched environment (EE. Using immunohistochemistry, we showed that dentate granule cells from EE-reared mice exhibited earlier morphological maturation, manifested as faster peaking of doublecortin expression and elevated expression of mature neuronal markers (including NeuN, calbindin and MAP2 at the end of the second postnatal week. Also at the end of the second postnatal week, we found increased density of dendritic spines across the entire dentate gyrus, together with elevated levels of postsynaptic scaffold (post-synaptic density 95 and receptor proteins (GluR2 and GABA(ARγ2 of excitatory and inhibitory synapses. Furthermore, dentate granule cells of P14 EE-reared mice had lower input resistances and increased glutamatergic and GABAergic synaptic inputs. Together, our results demonstrate that EE-rearing promotes morphological and electrophysiological maturation of dentate granule cells, underscoring the importance of natural environmental stimulation on development of the dentate gyrus.

  10. Myoelectric Signals from Paretic Wrist Extensor Controlling Electrical Stimulation of the Same Muscle

    DEFF Research Database (Denmark)

    Rune, Thorsen; Fin, Biering-Sørensen; Hansen, Steffen Duus

    1996-01-01

    A device for enhancement of the grip in C5/6 spinal cord lesioned tetraplegics is under development. It uses the myoelectric signal from the paretic wrist extensor for control of electrical stimulation of the same muscle. The tetraplegics shall with the device be able to obtain a passive grip bet...... between the thumb an the index finger by extension of the wrist. Surface electrodes are used for myoelectric recording and stimulation. Main problems are filtering of the recorded signal and stimulation. Solutions to these problems are addressed and discussed....

  11. Short time effect of Delta oscillation under microcurrent transcutaneous electrical nerve stimulation at ST36.

    Science.gov (United States)

    Li, Shunan; Li, Donghui; Li, Huiyan; Wang, Jiang

    2014-01-01

    This paper was to study the short time effect of Delta brain oscillation under microcurrent transcutaneous electrical nerve stimulation (MTENS) at ST36 (Zusanli). The 64-channal electroencephalograph (EEG) signals from 12 healthy volunteers were recorded including baseline stage, during stimulation and after stimulation. Autoregressive (AR) Burg method was used to estimate the power spectrum. Then power variation rate (PVR) was calculated to quantify the effects compared with the baseline in Delta band. The results showed that MTENS at ST36 on right side led to increased Delta band power in left frontal.

  12. Mandarin speech perception in combined electric and acoustic stimulation.

    Directory of Open Access Journals (Sweden)

    Yongxin Li

    Full Text Available For deaf individuals with residual low-frequency acoustic hearing, combined use of a cochlear implant (CI and hearing aid (HA typically provides better speech understanding than with either device alone. Because of coarse spectral resolution, CIs do not provide fundamental frequency (F0 information that contributes to understanding of tonal languages such as Mandarin Chinese. The HA can provide good representation of F0 and, depending on the range of aided acoustic hearing, first and second formant (F1 and F2 information. In this study, Mandarin tone, vowel, and consonant recognition in quiet and noise was measured in 12 adult Mandarin-speaking bimodal listeners with the CI-only and with the CI+HA. Tone recognition was significantly better with the CI+HA in noise, but not in quiet. Vowel recognition was significantly better with the CI+HA in quiet, but not in noise. There was no significant difference in consonant recognition between the CI-only and the CI+HA in quiet or in noise. There was a wide range in bimodal benefit, with improvements often greater than 20 percentage points in some tests and conditions. The bimodal benefit was compared to CI subjects' HA-aided pure-tone average (PTA thresholds between 250 and 2000 Hz; subjects were divided into two groups: "better" PTA (50 dB HL. The bimodal benefit differed significantly between groups only for consonant recognition. The bimodal benefit for tone recognition in quiet was significantly correlated with CI experience, suggesting that bimodal CI users learn to better combine low-frequency spectro-temporal information from acoustic hearing with temporal envelope information from electric hearing. Given the small number of subjects in this study (n = 12, further research with Chinese bimodal listeners may provide more information regarding the contribution of acoustic and electric hearing to tonal language perception.

  13. Adaptive fuzzy logic restriction rules for error correction and safe stimulation patterns during functional electrical stimulation.

    Science.gov (United States)

    Hansen, M; Haugland, M K

    2001-01-01

    Adaptive restriction rules based on fuzzy logic have been developed to eliminate errors and to increase stimulation safety in the foot-drop correction application, specifically when using adaptive logic networks to provide a stimulation control signal based on neural activity recorded from peripheral sensory nerve branches. The fuzzy rules were designed to increase flexibility and offer easier customization, compared to earlier versions of restriction rules. The rules developed quantified the duration of swing and stance phases into states of accepting or rejecting new transitions, based on the cyclic nature of gait and statistics on the current gait patterns. The rules were easy to custom design for a specific application, using linguistic terms to model the actions of the rules. The rules were tested using pre-recorded gait data processed through a gait event detector and proved to reduce detection delay and the number of errors, compared to conventional rules.

  14. Implantable power generation system utilizing muscle contractions excited by electrical stimulation.

    Science.gov (United States)

    Sahara, Genta; Hijikata, Wataru; Tomioka, Kota; Shinshi, Tadahiko

    2016-06-01

    An implantable power generation system driven by muscle contractions for supplying power to active implantable medical devices, such as pacemakers and neurostimulators, is proposed. In this system, a muscle is intentionally contracted by an electrical stimulation in accordance with the demands of the active implantable medical device for electrical power. The proposed system, which comprises a small electromagnetic induction generator, electrodes with an electrical circuit for stimulation and a transmission device to convert the linear motion of the muscle contractions into rotational motion for the magneto rotor, generates electrical energy. In an ex vivo demonstration using the gastrocnemius muscle of a toad, which was 28 mm in length and weighed 1.3 g, the electrical energy generated by the prototype exceeded the energy consumed for electrical stimulation, with the net power being 111 µW. It was demonstrated that the proposed implantable power generation system has the potential to replace implantable batteries for active implantable medical devices. © IMechE 2016.

  15. DC electric stimulation upregulates angiogenic factors in endothelial cells through activation of VEGF receptors.

    Science.gov (United States)

    Bai, Huai; Forrester, John V; Zhao, Min

    2011-07-01

    Small direct current (DC) electric fields direct some important angiogenic responses of vascular endothelial cells. Those responses indicate promising use of electric fields to modulate angiogenesis. We sought to determine the regulation of electric fields on transcription and expression of a serial of import angiogenic factors by endothelial cells themselves. Using semi-quantitative PCR and ELISA we found that electric stimulation upregulates the levels of mRNAs and proteins of a number of angiogenic proteins, most importantly VEGF165, VEGF121 and IL-8 in human endothelial cells. The up-regulation of mRNA levels might be specific, as the mRNA encoding bFGF, TGF-beta and eNOS are not affected by DC electric stimulation at 24h time-point. Inhibition of VEGF receptor (VEGFR1 or VEGFR2) signaling significantly decreased VEGF production and completely abolished IL-8 production. DC electric stimulation selectively regulates production of some growth factors and cytokines important for angiogenesis through a feed-back loop mediated by VEGF receptors. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Thermal electron acceleration by localized bursts of electric field in the radiation belts

    Science.gov (United States)

    Artemyev, A. V.; Agapitov, O. V.; Mozer, F.; Krasnoselskikh, V.

    2014-08-01

    In this paper we investigate the resonant interaction of thermal ˜10-100 eV electrons with a burst of electrostatic field that results in electron acceleration to kilovolt energies. This single burst contains a large parallel electric field of one sign and a much smaller, longer-lasting parallel field of the opposite sign. The Van Allen Probe spacecraft often observes clusters of spatially localized bursts in the Earth's outer radiation belts. These structures propagate mostly away from the geomagnetic equator and share properties of soliton-like nonlinear electron acoustic waves: a velocity of propagation is about the thermal velocity of cold electrons (˜3000-10,000 km/s), and a spatial scale of electric field localization along the field lines is about the Debye radius of hot electrons (˜5-30 km). We model the nonlinear resonant interaction of these electric field structures and cold background electrons.

  17. Particle acceleration by inductive electric fields in the Earth’s magnetosphere

    Science.gov (United States)

    Ilie, Raluca; Daldorff, Lars K. S.; Ganushkina, Natalia; Liemohn, Michael

    2015-04-01

    The terrestrial magnetosphere has the capability to rapidly accelerate charged particles up to very high energies over relatively short times and distances, leading to an increase in the near Earth currents. These energetic particles are injected from the magnetotail into the inner magnetosphere through two primary mechanisms. One transport method is the potential-driven convection. This occurs during periods of southward Interplanetary Magnetic Field (IMF), which allows part of the dawn-to-dusk solar wind electric field to effectively map down to the polar ionosphere. The second transport process, substorm activity, involves a sudden reconfiguration of the magnetic field and the creation of transient induced electric fields. The relative contribution of potential and inductive electric field driven convection resulting in the development of the storm-time ring current has remained an unresolved question in Geospace research.Since the energy of charged particles can be altered only by means of electric fields, knowledge of the relative contribution of potential versus inductive electric fields at intensifying the hot ion population in the inner magnetosphere is required. However, it is not possible to distinguish the two terms by only measuring the electric field. Therefore assessing the importance of induced electric field is possible by thorough examination of the time varying magnetic field and current systems using global modeling of the entire system.The induced electric field is calculated as a 3D integration over the entire magnetosphere domain. However, though computationally challenging, the full volume integration approach removes the need to trace independent field lines and lifts the assumption that the magnetic field lines can be treated as frozen in a stationary ionosphere.In this work, we quantitatively assess the relative contributions on potential and inductive electric fields at driving plasma sheet ions into the inner magnetosphere, as well as

  18. Cortical potentials after electrical intraneural stimulation of the optic nerve during orbital enucleation.

    Science.gov (United States)

    Benedičič, Mitja; Beltram, Matej; Olup, Brigita Drnovšek; Bošnjak, Roman

    2012-12-01

    The aim of this study was to present cortical potentials after electrical intraneural stimulation of the optic nerve during orbital enucleation due to malignant melanoma of the choroid or the ciliary body. These cortical potentials were related to cortical potentials after electrical epidural stimulation of the optic nerve, recorded during non-manipulative phases of neurosurgery for central skull base tumors. Cortical potentials were recorded with surface occipital electrode (Oz) in six patients undergoing orbital enucleation under total intravenous anesthesia. Two thin needle stimulating electrodes were inserted inside the intraorbital part of the optic nerve. The electrical stimulus consisted of a rectangular current pulse of varying intensity (0.2-10.0 mA) and duration (0.1-0.3 ms); the stimulation rate was 2 Hz; the bandpass filter was 1-1,000 Hz; the analysis time was 50-300 ms. Cortical potentials could not be obtained or were inconsistently elicitable in three patients with longstanding history (>3 months) of severe visual deterioration, while they consisted of several positive and negative deflections in a patient with a short history of mild visual impairment. In two other patients, cortical potentials consisted of N20, P30 and N40 waves. Cortical potentials after electrical intraneural stimulation of the optic nerve could be recorded in patients with a short history of visual deterioration and without optic nerve atrophy and appear more heterogeneous than cortical potentials after electrical epidural stimulation of the optic nerve, recorded during non-manipulative phases of neurosurgery for central skull base tumors.

  19. Effect of electrical vs. chemical deep brain stimulation at midbrain sites on micturition in anaesthetized rats.

    Science.gov (United States)

    Stone, E; Coote, J H; Lovick, T A

    2015-05-01

    To understand how deep brain stimulation of the midbrain influences control of the urinary bladder. In urethane-anaesthetized male rats, saline was infused continuously into the bladder to evoke cycles of filling and voiding. The effect of electrical (0.1-2.0 ms pulses, 5-180 Hz, 0.5-2.5 V) compared to chemical stimulation (microinjection of D,L-homocysteic acid, 50 nL 0.1 M solution) at the same midbrain sites was tested. Electrical stimulation of the periaqueductal grey matter and surrounding midbrain disrupted normal coordinated voiding activity in detrusor and sphincters muscles and suppressed urine output. The effect occurred within seconds was reversible and not secondary to cardiorespiratory changes. Bladder compliance remained unchanged. Chemical stimulation over the same area using microinjection of D,L-homocysteic acid (DLH) to preferentially activate somatodendritic receptors decreased the frequency of micturition but did not disrupt the coordinated pattern of voiding. In contrast, chemical stimulation within the caudal ventrolateral periaqueductal grey, in the area where critical synapses in the micturition reflex pathway are located, increased the frequency of micturition. Electrical deep brain stimulation within the midbrain can inhibit reflex micturition. We suggest that the applied stimulus entrained activity in the neural circuitry locally, thereby imposing an unphysiological pattern of activity. In a way similar to the use of electrical signals to 'jam' radio transmission, this may prevent a synchronized pattern of efferent activity being transmitted to the spinal outflows to orchestrate a coordinated voiding response. Further experiments to record neuronal firing in the midbrain during the deep brain stimulation will be necessary to test this hypothesis. © 2015 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

  20. Enhanced Working Memory Binding by Direct Electrical Stimulation of the Parietal Cortex

    Directory of Open Access Journals (Sweden)

    Agustina Birba

    2017-06-01

    Full Text Available Recent works evince the critical role of visual short-term memory (STM binding deficits as a clinical and preclinical marker of Alzheimer’s disease (AD. These studies suggest a potential role of posterior brain regions in both the neurocognitive deficits of Alzheimer’s patients and STM binding in general. Thereupon, we surmised that stimulation of the posterior parietal cortex (PPC might be a successful approach to tackle working memory deficits in this condition, especially at early stages. To date, no causal evidence exists of the role of the parietal cortex in STM binding. A unique approach to assess this issue is afforded by single-subject direct intracranial electrical stimulation of specific brain regions during a relevant cognitive task. Electrical stimulation has been used both for clinical purposes and to causally probe brain mechanisms. Previous evidence of electrical currents spreading through white matter along well defined functional circuits indicates that visual working memory mechanisms are subserved by a specific widely distributed network. Here, we stimulated the parietal cortex of a subject with intracranial electrodes as he performed the visual STM task. We compared the ensuing results to those from a non-stimulated condition and to the performance of a matched control group. In brief, direct stimulation of the parietal cortex induced a selective improvement in STM. These results, together with previous studies, provide very preliminary but promising ground to examine behavioral changes upon parietal stimulation in AD. We discuss our results regarding: (a the usefulness of the task to target prodromal stages of AD; (b the role of a posterior network in STM binding and in AD; and (c the potential opportunity to improve STM binding through brain stimulation.

  1. Accelerated intermittent Theta Burst stimulation for suicide risk in therapy-resistant depressed patients: a randomized, sham-controlled trial.

    Directory of Open Access Journals (Sweden)

    Stefanie Desmyter

    2016-09-01

    Full Text Available Objectives We aimed to examine the effects and safety of accelerated intermittent Theta Burst Stimulation (iTBS on suicide risk in a group of treatment-resistant unipolar depressed patients, using an extensive suicide assessment scale. Methods In 50 therapy-resistant, antidepressant-free depressed patients, an intensive protocol of accelerated iTBS was applied over the left dorsolateral prefrontal cortex in a randomized, sham-controlled cross-over design. Patients received 20 iTBS sessions over 4 days. Suicide risk was assessed using the Beck Scale of Suicide ideation (BSI. Results The iTBS protocol was safe and well-tolerated. We observed a significant decrease of the BSI score over time, unrelated to active or sham stimulation and unrelated to depression-response. No worsening of suicidal ideation was observed. The effects of accelerated iTBS on mood and depression severity are reported in Duprat et al. (2016. The decrease in suicide risk lasted up to one month after baseline, even in depression non-responders. Conclusions This accelerated iTBS protocol was safe. The observed significant decrease in suicide risk was unrelated to active or sham stimulation and unrelated to depression response. Further sham-controlled research in suicidal depressed patients is necessary.(clinicaltrials.gov identifier: NCT01832805

  2. Efficacy of brain-computer interface-driven neuromuscular electrical stimulation for chronic paresis after stroke.

    Science.gov (United States)

    Mukaino, Masahiko; Ono, Takashi; Shindo, Keiichiro; Fujiwara, Toshiyuki; Ota, Tetsuo; Kimura, Akio; Liu, Meigen; Ushiba, Junichi

    2014-04-01

    Brain computer interface technology is of great interest to researchers as a potential therapeutic measure for people with severe neurological disorders. The aim of this study was to examine the efficacy of brain computer interface, by comparing conventional neuromuscular electrical stimulation and brain computer interface-driven neuromuscular electrical stimulation, using an A-B-A-B withdrawal single-subject design. A 38-year-old male with severe hemiplegia due to a putaminal haemorrhage participated in this study. The design involved 2 epochs. In epoch A, the patient attempted to open his fingers during the application of neuromuscular electrical stimulation, irrespective of his actual brain activity. In epoch B, neuromuscular electrical stimulation was applied only when a significant motor-related cortical potential was observed in the electroencephalogram. The subject initially showed diffuse functional magnetic resonance imaging activation and small electro-encephalogram responses while attempting finger movement. Epoch A was associated with few neurological or clinical signs of improvement. Epoch B, with a brain computer interface, was associated with marked lateralization of electroencephalogram (EEG) and blood oxygenation level dependent responses. Voluntary electromyogram (EMG) activity, with significant EEG-EMG coherence, was also prompted. Clinical improvement in upper-extremity function and muscle tone was observed. These results indicate that self-directed training with a brain computer interface may induce activity- dependent cortical plasticity and promote functional recovery. This preliminary clinical investigation encourages further research using a controlled design.

  3. Clinical efficacy of electrical stimulation exercise training : Effects on health, fitness, and function

    NARCIS (Netherlands)

    Janssen, T. W J; Glaser, R. M.; Shuster, D. B.

    1998-01-01

    The purpose of this article is to summarize research findings pertaining to the effects of functional electrical stimulation (FES) lower limb exercise training on health, fitness, and function in individuals with spinal cord injury. This lays the foundation for defining the potential clinical

  4. Effects of haloperidol on behavioral responses induced by electrical stimulation of medial prefrontal cortex.

    Science.gov (United States)

    Nakamura-Palacios, E M

    1996-10-01

    The effects of haloperidol on circling and spying behaviors induced by electrical stimulation of the medial prefrontal cortex (PFC) were evaluated. Male Wistar rats with an electrode implanted into the left medial PFC (B: 2.5 mm A, 0.6 mm L and 2.7 mm V) were electrically stimulated in a sequence of ten 30-sec trains separated by 30-sec intervals (60 Hz) in each session, and simultaneously observed in the open field. The animals with circling (CI) and spying (SP) behaviors were treated with intraperitoneal haloperidol (HAL ip, 5 mg/kg, N = 6) and saline (SAL ip, N = 7) or intracortical HAL (ic, 5 micrograms, N = 6) and SAL (ic, N = 9), 20 min before the session of electrical stimulation. HAL ic significantly decreased (P < 0.05) CI (mean frequency +/- SEM: 0.5 +/- 0.16) and nonsignificantly decreased SP behavior (0.6 +/- 0.17) compared to SAL ic (CI: 0.9 0.02, SP: 1 +/- 0). HAL ip full abolished these behaviors (P < 0.05) (CI: 0.02 +/- 0, SP: 1 +/- 0) compared to SAL ip (CI: 0.86 +/- 0.06, SP: 0:93 +/- 0.06). These results show that haloperidol, a dopaminergic antagonist and antipsychotic agent, interfered significantly with the expression of behaviors induced by electrical stimulation of the left medial PFC, suggesting that the induction of these behaviors may involve the dopaminergic neurotransmission.

  5. Electrical stimulation of sacral dermatomes in multiple sclerosis patients with neurogenic detrusor overactivity.

    NARCIS (Netherlands)

    Fjorback, M.V.; Rey, F. van; Rijkhoff, N.J.M.; Nohr, M.; Petersen, T.; Heesakkers, J.P.

    2007-01-01

    AIMS: Transcutaneous electrical stimulation of the dorsal penile/clitoral nerve (DPN) has been shown to suppress detrusor contractions in patients with neurogenic detrusor overactivity (NDO). However, the long-term use of surface electrodes in the genital region may not be well tolerated and may

  6. Controlling your impulses: Electrical stimulation of the human supplementary motor complex prevents impulsive errors

    NARCIS (Netherlands)

    Spieser, L.; van den Wildenberg, W.; Hasbroucq, T.; Ridderinkhof, K.R.; Burle, B.

    2015-01-01

    To err is human. However, an inappropriate urge does not always result in error. Impulsive errors thus entail both a motor system capture by an urge to act and a failed inhibition of that impulse. Here we show that neuromodulatory electrical stimulation of the supplementary motor complex in healthy

  7. Effects of electric stimulation-assisted cycling training in people with chronic stroke

    NARCIS (Netherlands)

    Janssen, T.W.J.; Beltman, J.M.; Elich, P.; Koppe, P.A.; Konijnenbelt, H.; de Haan, A.; Gerrits, K.H.L.

    2008-01-01

    Janssen TW, Beltman JM, Elich P, Koppe PA, Konijnenbelt H, de Haan A, Gerrits KH. Effects of electric stimulation-assisted cycling training in people with chronic stroke. Objective: To evaluate whether leg cycling training in subjects with chronic stroke can improve cycling performance, aerobic

  8. Evidence of skeletal muscle damage following electrically stimulated isometric muscle contractions in humans

    DEFF Research Database (Denmark)

    Mackey, Abigail; Bojsen-Moller, Jens; Qvortrup, Klaus

    2008-01-01

    It is unknown whether muscle damage at the level of the sarcomere can be induced without lengthening contractions. To investigate this, we designed a study where seven young, healthy men underwent 30 min of repeated electrical stimulated contraction of m. gastrocnemius medialis, with the ankle an...

  9. Electrical stimulation therapy for slow transit constipation in children: a systematic review.

    Science.gov (United States)

    Lu, Ming-Liang; He, Jin; Lu, Shifeier

    2015-05-01

    Slow transit constipation is a common disorder in children, which often does not respond well to ordinary treatments. We have conducted a systematic review of reported studies in order to better define the current state of knowledge about electrical stimulation treatment of slow transit constipation in children. We searched PubMed, Embase, Cochrane Library, BioMed Central, and ISI Web of Knowledge with relevant terms; six studies, all from one center, met the criteria for inclusion. Two trials were randomized clinical trials, and four were prospective studies. The number of subjects included in the studies was 8 to 39, with ages 3 to 18 years. Treatment sessions varied from 20 to 30 min 3 times per week to 1 h daily, and duration of therapy varied from 3 weeks to 6 months. Statistically significant improvements after electrical stimulation therapy were recorded in one to four outcome measures in each of the studies: frequency of defecation, soiling, Bristol Stool Scale, radionuclear transit studies, and quality of life; however, the improvements were of modest degree and of uncertain clinical significance. Quality assessment of the studies found various levels of bias, with attrition bias and reporting bias in all six. This systemic review found moderate support for the effectiveness of electrical stimulation therapy in slow transit constipation in children. However, better-designed studies, with larger and more diverse patient populations followed for longer time periods, will be needed in order to reliably determine the efficacy of electrical stimulation therapy in the treatment of this disorder.

  10. Comparison of electrical stimulation methods for reduction of triceps sureae spasticiy in SCI-patients

    NARCIS (Netherlands)

    van der Salm, Arjan; Veltink, Petrus H.; IJzerman, Maarten Joost; Groothuis-Oudshoorn, Catharina Gerarda Maria; Nene, A.V.; Hermens, Hermanus J.

    Objectives To compare the effect of 3 methods of electric stimulation to reduce spasticity of the triceps surae in patients with complete spinal cord injury (SCI) and to investigate the carryover effect. Design Placebo-controlled study with repeated measurements after the interventions. Setting

  11. [Long-term evaluation of spinal cord electric stimulation in peripheral vascular disease].

    Science.gov (United States)

    Duato Jané, A; Lorente Navarro, C; Azcona Elizalde, J M; Revilla Martín, J M; Marsal Machín, T; Buisán Bardají, J M

    1993-01-01

    We reported an study about the Electric Medullar Stimulation on Peripheral Vascular Pathology, in cases of critical Ischaemia of lower limbs. Short-time and longtime results are exposed. Arteriopathies included into the study were: arteriosclerosis, "mixed arteriopathy and TAO". Examination was made by Doppler-Ultrasonography.

  12. Effects of transcutaneous electrical nerve stimulation (TENS) on cognition and behaviour in aging

    NARCIS (Netherlands)

    Scherder, E.J A; van Someren, E.W J; Bouma, J.M.; van der Berg, M

    2000-01-01

    In previous studies, transcutaneous electrical nerve stimulation (TENS) improved cognition and behaviour in patients with Alzheimer's disease (AD). The rationale underlying these studies was that TENS could activate, e.g. the septo-hippocampal region and the hypothalamus through direct and indirect

  13. Effects of transcutaneous electrical nerve stimulation (TENS) on memory in elderly with mild cognitive impairment

    NARCIS (Netherlands)

    Luijpen, MW; Swaab, DF; Sergeant, JA; van Dijk, KRA; Scherder, EJA

    2005-01-01

    In previous studies, transcutaneous electrical nerve stimulation (TENS) was shown to have a positive effect on memory in Alzheimer's disease (AD) patients. Moreover, the reported effects appeared to be more beneficial in early stages of Alzheimer's disease compared to later stage intervention. Based

  14. Effects of transcutaneous electrical nerve stimulation (TENS) on memory in elderly with mild cognitive impairment.

    NARCIS (Netherlands)

    Luijpen, M.W.; Swaab, D.F.; Sergeant, J.A.; Dijk, K.R.A.; Scherder, E.J.

    2005-01-01

    In previous studies, transcutaneous electrical nerve stimulation (TENS) was shown to have a positive effect on memory in Alzheimer's disease (AD) patients. Moreover, the reported effects appeared to be more beneficial in early stages of Alzheimer's disease compared to later stage intervention. Based

  15. Functional electrical stimulation-assisted walking for persons with incomplete spinal injuries

    DEFF Research Database (Denmark)

    Ladouceur, M.; Barbeau, H.

    2000-01-01

    This study investigated the changes in maximal overground walking speed (MOWS) that occurred during; walking training with a functional electrical stimulation (FES) orthosis by chronic spinal cord injured persons with incomplete motor function loss. The average walking: speed over a distance of 10...

  16. Electrospun conducting polymer nanofibers and electrical stimulation of nerve stem cells.

    Science.gov (United States)

    Prabhakaran, Molamma P; Ghasemi-Mobarakeh, Laleh; Jin, Guorui; Ramakrishna, Seeram

    2011-11-01

    Tissue engineering of nerve grafts requires synergistic combination of scaffolds and techniques to promote and direct neurite outgrowth across the lesion for effective nerve regeneration. In this study, we fabricated a composite polymeric scaffold which is conductive in nature by electrospinning and further performed electrical stimulation of nerve stem cells seeded on the electrospun nanofibers. Poly-L-lactide (PLLA) was blended with polyaniline (PANi) at a ratio of 85:15 and electrospun to obtain PLLA/PANi nanofibers with fiber diameters of 195 ± 30 nm. The morphology, chemical and mechanical properties of the electrospun PLLA and PLLA/PANi scaffolds were carried out by scanning electron microscopy (SEM), X-ray photo electron spectroscopy (XPS) and tensile instrument. The electrospun PLLA/PANi fibers showed a conductance of 3 × 10⁻⁹ S by two-point probe measurement. In vitro electrical stimulation of the nerve stem cells cultured on PLLA/PANi scaffolds applied with an electric field of 100 mV/mm for a period of 60 min resulted in extended neurite outgrowth compared to the cells grown on non-stimulated scaffolds. Our studies further strengthen the implication of electrical stimulation of nerve stem cells on conducting polymeric scaffolds towards neurite elongation that could be effective for nerve tissue regeneration. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  17. Control of thumb force using surface functional electrical stimulation and muscle load sharing

    NARCIS (Netherlands)

    Westerveld, A.J.; Schouten, A.C.; Veltink, P.H.; Van der Kooij, H.

    2013-01-01

    Background Stroke survivors often have difficulties in manipulating objects with their affected hand. Thumb control plays an important role in object manipulation. Surface functional electrical stimulation (FES) can assist movement. We aim to control the 2D thumb force by predicting the sum of

  18. Control of thumb force using surface functional electrical stimulation and muscle load sharing

    NARCIS (Netherlands)

    Westerveld, Ard; Westerveld, Ard J.; Schouten, Alfred Christiaan; Veltink, Petrus H.; van der Kooij, Herman

    2013-01-01

    Background: Stroke survivors often have difficulties in manipulating objects with their affected hand. Thumb control plays an important role in object manipulation. Surface functional electrical stimulation (FES) can assist movement. We aim to control the 2D thumb force by predicting the sum of

  19. Evidence-Based Systematic Review: Effects of Neuromuscular Electrical Stimulation on Swallowing and Neural Activation

    Science.gov (United States)

    Clark, Heather; Lazarus, Cathy; Arvedson, Joan; Schooling, Tracy; Frymark, Tobi

    2009-01-01

    Purpose: To systematically review the literature examining the effects of neuromuscular electrical stimulation (NMES) on swallowing and neural activation. The review was conducted as part of a series examining the effects of oral motor exercises (OMEs) on speech, swallowing, and neural activation. Method: A systematic search was conducted to…

  20. Nociception-related somatosensory evoked potentials in awake dogs recorded after intra epidermal electrical stimulation

    NARCIS (Netherlands)

    van Oostrom, H.; Stienen, P.J.; Doornenbal, A.; Hellebrekers, L.J.

    2009-01-01

    Eur J Pain. 2009 Feb;13(2):154-60. Epub 2008 May 16. Nociception-related somatosensory evoked potentials in awake dogs recorded after intra epidermal electrical stimulation. van Oostrom H, Stienen PJ, Doornenbal A, Hellebrekers LJ. Department of Clinical Sciences of Companion Animals, Division

  1. A functional electrical stimulation system for human walking inspired by reflexive control principles.

    Science.gov (United States)

    Meng, Lin; Porr, Bernd; Macleod, Catherine A; Gollee, Henrik

    2017-04-01

    This study presents an innovative multichannel functional electrical stimulation gait-assist system which employs a well-established purely reflexive control algorithm, previously tested in a series of bipedal walking robots. In these robots, ground contact information was used to activate motors in the legs, generating a gait cycle similar to that of humans. Rather than developing a sophisticated closed-loop functional electrical stimulation control strategy for stepping, we have instead utilised our simple reflexive model where muscle activation is induced through transfer functions which translate sensory signals, predominantly ground contact information, into motor actions. The functionality of the functional electrical stimulation system was tested by analysis of the gait function of seven healthy volunteers during functional electrical stimulation-assisted treadmill walking compared to unassisted walking. The results demonstrated that the system was successful in synchronising muscle activation throughout the gait cycle and was able to promote functional hip and ankle movements. Overall, the study demonstrates the potential of human-inspired robotic systems in the design of assistive devices for bipedal walking.

  2. Self directed home based electrical muscle stimulation training improves exercise tolerance and strength in healthy elderly.

    Science.gov (United States)

    Caulfield, Brian; Prendergast, Ann; Rainsford, Gary; Minogue, Conor

    2013-01-01

    Advancing age is associated with a gradual decline in muscle strength, exercise tolerance and subsequent capacity for activities of daily living. It is important that we develop effective strategies to halt this process of gradual decline in order to enhance functional ability and capacity for independent living. To achieve this, we must overcome the challenge of sustaining ongoing engagement in physical exercise programmes in the sedentary elderly population, particularly those who experience barriers to exercise participation. Recent developments in electrical muscle stimulation technology could provide a potential solution. In this pilot case-control study we investigated the effects of a self-directed home based programme of electrical muscle stimulation training on muscle strength and exercise tolerance in a group of 16 healthy elderly volunteers (10f, 6m). Study participants completed 30 separate 1-hour electrical muscle stimulation sessions at home over a 6-week period. We observed significant improvements in quadriceps muscle strength and 6-minute walk distance, suggesting that this form of electrical muscle stimulation training has promise as an exercise modality in the elderly population.

  3. Angiotensin II modulates conducted vasoconstriction to norepinephrine and local electrical stimulation in rat mesenteric arterioles

    DEFF Research Database (Denmark)

    Gustafsson, F; Holstein-Rathlou, N H

    1999-01-01

    the effect of intravenous infusion of angiotensin II (ANG II), losartan or methoxamine on conducted vasoconstriction to local application of norepinephrine (NE) or local electrical stimulation onto the surface of rat mesenteric arterioles in vivo. METHODS: In anesthetized male Wistar rats (n = 43) NE (0.1 m...

  4. Aligned Nanofibers from Polypyrrole/Graphene as Electrodes for Regeneration of Optic Nerve via Electrical Stimulation.

    Science.gov (United States)

    Yan, Lu; Zhao, Bingxin; Liu, Xiaohong; Li, Xuan; Zeng, Chao; Shi, Haiyan; Xu, Xiaoxue; Lin, Tong; Dai, Liming; Liu, Yong

    2016-03-23

    The damage of optic nerve will cause permanent visual field loss and irreversible ocular diseases, such as glaucoma. The damage of optic nerve is mainly derived from the atrophy, apoptosis or death of retinal ganglion cells (RGCs). Though some progress has been achieved on electronic retinal implants that can electrically stimulate undamaged parts of RGCs or retina to transfer signals, stimulated self-repair/regeneration of RGCs has not been realized yet. The key challenge for development of electrically stimulated regeneration of RGCs is the selection of stimulation electrodes with a sufficient safe charge injection limit (Q(inj), i.e., electrochemical capacitance). Most traditional electrodes tend to have low Q(inj) values. Herein, we synthesized polypyrrole functionalized graphene (PPy-G) via a facile but efficient polymerization-enhanced ball milling method for the first time. This technique could not only efficiently introduce electron-acceptor nitrogen to enhance capacitance, but also remain a conductive platform-the π-π conjugated carbon plane for charge transportation. PPy-G based aligned nanofibers were subsequently fabricated for guided growth and electrical stimulation (ES) of RGCs. Significantly enhanced viability, neurite outgrowth and antiaging ability of RGCs were observed after ES, suggesting possibilities for regeneration of optic nerve via ES on the suitable nanoelectrodes.

  5. Modeling transcranial electric stimulation in mouse: a high resolution finite element study.

    Science.gov (United States)

    Bernabei, John M; Lee, Won Hee; Peterchev, Angel V

    2014-01-01

    Mouse models are widely used in studies of various forms of transcranial electric stimulation (TES). However, there is limited knowledge of the electric field distribution induced by TES in mice, and computational models to estimate this distribution are lacking. This study examines the electric field and current density distribution in the mouse brain induced by TES. We created a high-resolution finite element mouse model incorporating ear clip electrodes commonly used in mouse TES to study, for example, electroconvulsive therapy (ECT). The electric field strength and current density induced by an ear clip electrode configuration were computed in the anatomically realistic, inhomogenous mouse model. The results show that the median electric field strength induced in the brain at 1 mA of stimulus current is 5.57 V/m, and the strongest field of 20.19 V/m was observed in the cerebellum. Therefore, to match the median electric field in human ECT at 800 mA current, the electrode current in mouse should be set to approximately 15 mA. However, the location of the strongest electric field in posterior brain regions in the mouse does not model well human ECT which targets more frontal regions. Therefore, the ear clip electrode configuration may not be a good model of human ECT. Using high-resolution realistic models for simulating TES in mice may guide the establishment of appropriate stimulation parameters for future in vivo studies.

  6. Cortical mapping of painful electrical stimulation by quantitative electroencephalography: unraveling the time–frequency–channel domain

    Directory of Open Access Journals (Sweden)

    Goudman L

    2017-11-01

    Full Text Available Lisa Goudman,1–3 Jorne Laton,4 Raf Brouns,4,5 Guy Nagels,4–6 Eva Huysmans,2,3,7,8 Ronald Buyl,7,9 Kelly Ickmans,2,3,10 Jo Nijs,2,3,10 Maarten Moens,1,2,4,11 1Department of Neurosurgery, Universitair Ziekenhuis Brussel, 2Pain in Motion International Research Group, 3Department of Physiotherapy, Human Physiology and Anatomy, Faculty of Physical Education and Physiotherapy, 4Center for Neurosciences (C4N, Vrije Universiteit Brussel (VUB, 5Department of Neurology, Universitair Ziekenhuis Brussel, 6National MS Center, 7Department of Public Health (GEWE, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, 8Interuniversity Centre for Health Economics Research (I-CHER, 9Department of Biostatistics and Medical Informatics, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, 10Department of Physical Medicine and Physiotherapy, 11Department of Radiology, Universitair Ziekenhuis Brussel, Brussels, Belgium Abstract: The goal of this study was to capture the electroencephalographic signature of experimentally induced pain and pain-modulating mechanisms after painful peripheral electrical stimulation to determine one or a selected group of electrodes at a specific time point with a specific frequency range. In the first experiment, ten healthy participants were exposed to stimulation of the right median nerve while registering brain activity using 32-channel electroencephalography. Electrical stimulations were organized in four blocks of 20 stimuli with four intensities – 100%, 120%, 140%, and 160% – of the electrical pain threshold. In the second experiment, 15 healthy participants received electrical stimulation on the dominant median nerve before and during the application of a second painful stimulus. Raw data were converted into the time–frequency domain by applying a continuous wavelet transform. Separated domain information was extracted by calculating Parafac models. The results demonstrated that it is possible to capture

  7. Posterolateral surface electrical stimulation of abdominal expiratory muscles to enhance cough in spinal cord injury.

    Science.gov (United States)

    Butler, Jane E; Lim, Julianne; Gorman, Robert B; Boswell-Ruys, Claire; Saboisky, Julian P; Lee, Bonsan B; Gandevia, Simon C

    2011-02-01

    Spinal cord injury (SCI) patients have respiratory complications because of abdominal muscle weakness and paralysis, which impair the ability to cough. This study aims to enhance cough in high-level SCI subjects (n = 11, SCI at or above T6) using surface electrical stimulation of the abdominal muscles via 2 pairs of posterolaterally placed electrodes. From total lung capacity, subjects performed maximum expiratory pressure (MEP) efforts against a closed airway and voluntary cough efforts. Both efforts were performed with and without superimposed trains of electrical stimulation (50 Hz, 1 second) at a submaximal intensity set to evoke a gastric pressure (P(ga)) of 40 cm H(2)O at functional residual capacity. In the MEP effort, stimulation increased the maximal P(ga) (from 21.4 ± 7.0 to 59.0 ± 5.7 cm H(2)O) and esophageal pressure (P(es); 47.2 ± 11.7 to 65.6 ± 13.6 cm H(2)O). During the cough efforts, stimulation increased P(ga) (19.5 ± 6.0 to 57.9 ± 7.0 cm H(2)O) and P(es) (31.2 ± 8.7 to 56.6 ± 10.5 cm H(2)O). The increased expiratory pressures during cough efforts with stimulation increased peak expiratory flow (PEF, by 36% ± 5%), mean expiratory flow (by 80% ± 8%), and expired lung volume (by 41% ± 16%). In every subject, superimposed electrical stimulation improved peak expiratory flow during cough efforts (by 0.99 ± 0.12 L/s; range, 0.41-1.80 L/s). Wearing an abdominal binder did not improve stimulated cough flows or pressures. The increases in P(ga) and PEF with electrical stimulation using the novel posterolateral electrode placement are 2 to 3 times greater than improvements reported in other studies. This suggests that posterolateral electrical stimulation of abdominal muscles is a simple noninvasive way to enhance cough in individuals with SCI.

  8. Cell-stimulation therapy of lateral epicondylitis with frequency-modulated low-intensity electric current.

    Science.gov (United States)

    Aliyev, R M; Geiger, G

    2012-03-01

    In addition to the routine therapy, the patients with lateral epicondylitis included into experimental group were subjected to a 12-week cell-stimulation therapy with low-intensity frequency-modulated electric current. The control group received the same routine therapy and sham stimulation (the therapeutic apparatus was not energized). The efficiency of this microcurrent therapy was estimated by comparing medical indices before therapy and at the end of a 12-week therapeutic course using a 10-point pain severity numeric rating scale (NRS) and Roles-Maudsley pain score. The study revealed high therapeutic efficiency of cell-stimulation with low-intensity electric current resulting probably from up-regulation of intracellular transmitters, interleukins, and prostaglandins playing the key role in the regulation of inflammation.

  9. [Paraplegic cycling using functional electrical stimulation. Experimental and model-based study of power output].

    Science.gov (United States)

    Szecsi, J; Krafczyk, S; Quintern, J; Fiegel, M; Straube, A; Brandt, T

    2004-12-01

    Cycling using functional electrical stimulation offers paraplegics the possibility of muscle and cardiovascular training as well as the chance for independent locomotion. To investigate whether this method might be suitable for a large group of paraplegics, the first German feasibility study of functional electrical stimulation (FES) cycling with seven paraplegic patients was started at the beginning of 2003. Even at the beginning of the study, and without training, these patients were able to drive distances of 0.5-1.6 km. To stimulate cardiovascular adaptation processes in the case of FES ergometer training or to cover useful distances in the case of FES cycling, a minimum amount of generated mechanical output power is required, which as a rule cannot be achieved yet. In this study, we point out two particular aspects of FES cycling, which impair power output: prolonged fatigue mode and viscous joint friction of the paraplegic FES cyclist. We discuss current possibilities for increasing output power and endurance.

  10. Muscle reflexes during gait elicited by electrical stimulation of the posterior cruciate ligament in humans

    DEFF Research Database (Denmark)

    Fischer-Rasmussen, T; Krogsgaard, M R; Jensen, D B

    2002-01-01

    We investigated the influence of electrical stimulation of the posterior cruciate ligament (PCL) on the motoneuron pool of the thigh and calf muscle during gait. The study group comprised eight young men without any history of injury to the knee joints. Multistranded teflon-insulated stainless...... over the vastus medialis, rectus femoris, vastus lateralis, biceps femoris caput longum, and semitendinosus muscles. The stimuli consisted of four pulses delivered at 200 Hz; the stimulus amplitude was two to three times the sensory threshold. The electrical stimulation of the PCL inhibited the ongoing...... muscle activity in both the quadriceps and the hamstrings. The latency of the inhibition ranged between 78 and 148 ms in the quadriceps, between 88 and 110 ms in the hamstrings and between 189 and 258 ms in m. gastrocnemius. Stimulation of the fat pad of the knee did not influence the thigh and calf...

  11. Turning on the central contribution to contractions evoked by neuromuscular electrical stimulation.

    Science.gov (United States)

    Dean, J C; Yates, L M; Collins, D F

    2007-07-01

    Neuromuscular electrical stimulation can generate contractions through peripheral and central mechanisms. Direct activation of motor axons (peripheral mechanism) recruits motor units in an unnatural order, with fatigable muscle fibers often activated early in contractions. The activation of sensory axons can produce contractions through a central mechanism, providing excitatory synaptic input to spinal neurons that recruit motor units in the natural order. Presently, we quantified the effect of stimulation frequency (10-100 Hz), duration (0.25-2 s of high-frequency bursts, or 20 s of constant-frequency stimulation), and intensity [1-5% maximal voluntary contraction (MVC) torque generated by a brief 100-Hz train] on the torque generated centrally. Electrical stimulation (1-ms pulses) was delivered over the triceps surae in eight subjects, and plantar flexion torque was recorded. Stimulation frequency, duration, and intensity all influenced the magnitude of the central contribution to torque. Central torque did not develop at frequencies or = 80 Hz. Increasing the duration of high-frequency stimulation increased the central contribution to torque, as central torque developed over 11 s. Central torque was greatest at a relatively low contraction intensity. The largest amount of central torque was produced by a 20-s, 100-Hz train (10.7 +/- 5.5 %MVC) and by repeated 2-s bursts of 80- or 100-Hz stimulation (9.2 +/- 4.8 and 10.2 +/- 8.1% MVC, respectively). Therefore, central torque was maximized by applying high-frequency, long-duration stimulation while avoiding antidromic block by stimulating at a relatively low intensity. If, as hypothesized, the central mechanism primarily activates fatigue-resistant muscle fibers, generating muscle contractions through this pathway may improve rehabilitation applications.

  12. Electrical Stimulation of Eye Blink in Individuals with Acute Facial Palsy: Progress toward a Bionic Blink.

    Science.gov (United States)

    Frigerio, Alice; Heaton, James T; Cavallari, Paolo; Knox, Chris; Hohman, Marc H; Hadlock, Tessa A

    2015-10-01

    Elicitation of eye closure and other movements via electrical stimulation may provide effective treatment for facial paralysis. The authors performed a human feasibility study to determine whether transcutaneous neural stimulation can elicit a blink in individuals with acute facial palsy and to obtain feedback from participants regarding the tolerability of surface electrical stimulation for daily blink restoration. Forty individuals with acute unilateral facial paralysis, HB grades 4 through 6, were prospectively studied between 6 and 60 days of onset. Unilateral stimulation of zygomatic facial nerve branches to elicit eye blink was achieved with brief bipolar, charge-balanced pulse trains, delivered transcutaneously by adhesive electrode placement; results were recorded on a high-speed video camera. The relationship between stimulation parameters and cutaneous sensation was analyzed using the Wong-Baker Faces Pain Rating Scale. Complete eye closure was achieved in 55 percent of participants using stimulation parameters reported as tolerable. In those individuals, initial eye twitch was observed at an average current of 4.6 mA (±1.7; average pulse width of 0.7 ms, 100 to 150 Hz), with complete closure requiring a mean of 7.2 mA (±2.6). Transcutaneous facial nerve stimulation may artificially elicit eye blink in a majority of patients with acute facial paralysis. Although individuals varied widely in their reported degrees of discomfort from blink-eliciting stimulation, most of them indicated that such stimulation would be tolerable if it could restore eye closure. These patients would therefore benefit from a biomimetic device to facilitate eye closure until the recovery process is complete. Therapeutic, IV.

  13. Effects of Dual-Channel Functional Electrical Stimulation on Gait Performance in Patients with Hemiparesis

    Directory of Open Access Journals (Sweden)

    Shmuel Springer

    2012-01-01

    Full Text Available The study objective was to assess the effect of functional electrical stimulation (FES applied to the peroneal nerve and thigh muscles on gait performance in subjects with hemiparesis. Participants were 45 subjects (age 57.8 ± 14.8 years with hemiparesis (5.37 ± 5.43 years since diagnosis demonstrating a foot-drop and impaired knee control. Thigh stimulation was applied either to the quadriceps or hamstrings muscles, depending on the dysfunction most affecting gait. Gait was assessed during a two-minute walk test with/without stimulation and with peroneal stimulation alone. A second assessment was conducted after six weeks of daily use. The addition of thigh muscles stimulation to peroneal stimulation significantly enhanced gait velocity measures at the initial and second evaluation. Gait symmetry was enhanced by the dual-channel stimulation only at the initial evaluation, and single-limb stance percentage only at the second assessment. For example, after six weeks, the two-minute gait speed with peroneal stimulation and with the dual channel was 0.66 ± 0.30 m/sec and 0.70 ± 0.31 m/sec, respectively (. In conclusion, dual-channel FES may enhance gait performance in subjects with hemiparesis more than peroneal FES alone.

  14. Effect of Neuromuscular Electrical Muscle Stimulation on Energy Expenditure in Healthy Adults

    Directory of Open Access Journals (Sweden)

    Ya-Ju Chang

    2011-02-01

    Full Text Available Weight loss/weight control is a major concern in prevention of cardiovascular disease and the realm of health promotion. The primary aim of this study was to investigate the effect of neuromuscular electrical stimulation (NMES at different intensities on energy expenditure (oxygen and calories in healthy adults. The secondary aim was to develop a generalized linear regression (GEE model to predict the increase of energy expenditure facilitated by NMES and identify factors (NMES stimulation intensity level, age, body mass index, weight, body fat percentage, waist/hip ratio, and gender associated with this NMES-induced increase of energy expenditure. Forty sedentary healthy adults (18 males and 22 females participated. NMES was given at the following stimulation intensities for 10 minutes each: sensory level (E1, motor threshold (E2, and maximal intensity comfortably tolerated (E3. Cardiopulmonary gas exchange was evaluated during rest, NMES, and recovery stage. The results revealed that NMES at E2 and E3 significantly increased energy expenditure and the energy expenditure at recovery stage was still significantly higher than baseline. The GEE model demonstrated that a linear dose-response relationship existed between the stimulation intensity and the increase of energy expenditure. No subject’s demographic or anthropometric characteristics tested were significantly associated with the increase of energy expenditure. This study suggested NMES may be used to serve as an additional intervention for weight loss programs. Future studies to develop electrical stimulators or stimulation electrodes to maximize the comfort of NMES are recommended.

  15. Cerebellar and Spinal Direct Current Stimulation in Children: Computational Modeling of the Induced Electric Field.

    Science.gov (United States)

    Fiocchi, Serena; Ravazzani, Paolo; Priori, Alberto; Parazzini, Marta

    2016-01-01

    Recent studies have shown that the specific application of transcranial direct current stimulation (tDCS) over the cerebellum can modulate cerebellar activity. In parallel, transcutaneous spinal DC stimulation (tsDCS) was found to be able to modulate conduction along the spinal cord and spinal cord functions. Of particular interest is the possible use of these techniques in pediatric age, since many pathologies and injuries, which affect the cerebellar cortex as well as spinal cord circuits, are diffuse in adults as well as in children. Up to now, experimental studies of cerebellar and spinal DC stimulation on children are completely missing and therefore there is a lack of information about the safety of this technique as well as the appropriate dose to be used during the treatment. Therefore, the knowledge of electric quantities induced into the cerebellum and over the spinal cord during cerebellar tDCS and tsDCS, respectively, is required. This work attempts to address this issue by estimating through computational techniques, the electric field distributions induced in the target tissues during the two stimulation techniques applied to different models of children of various ages and gender. In detail, we used four voxel child models, aged between 5- and 8-years. Results revealed that, despite inter-individual differences, the cerebellum is the structure mainly involved by cerebellar tDCS, whereas the electric field generated by tsDCS can reach the spinal cord also in children. Moreover, it was found that there is a considerable spread toward the anterior area of the cerebellum and the brainstem region for cerebellar tDCS and in the spinal nerve for spinal direct current stimulation. Our study therefore predicts that the electric field spreads in complex patterns that strongly depend on individual anatomy, thus giving further insight into safety issues and informing data for pediatric investigations of these stimulation techniques.

  16. Optical imaging of the retina in response to the electrical stimulation

    Science.gov (United States)

    Fujikado, Takashi; Okawa, Yoshitaka; Miyoshi, Tomomitsu; Hirohara, Yoko; Mihashi, Toshifumi; Tano, Yasuo

    2008-02-01

    Purposes: To determine if reflectance changes of the retina can be detected following electrical stimulation to the retina using a newly developed optical-imaging fundus camera. Methods: Eyes of cats were examined after pupil dilation. Retina was stimulated either focally by a ball-type electrode (BE) placed on the fenestrated sclera or diffusely using a ring-type electrode (RE) placed on the corneoscleral limbus. Electrical stimulation by biphasic pulse trains was applied for 4 seconds. Fundus images with near-infrared (800-880 nm) light were obtained between 2 seconds before and 20 seconds after the electrical stimulation (ES). A two-dimensional map of the reflectance changes (RCs) was constructed. The effect of Tetrodotoxin (TTX) was also investigated on RCs by ES using RE. Results: RCs were observed around the retinal locus where the stimulating electrodes were positioned (BE) or in the retina of the posterior pole (RE), in which the latency was about 0.5 to 1.0 sec and the peak time about 2 to 5 sec after the onset of ES. The intensity of the RCs increased with the increase of the stimulus current in both cases. RCs were completely suppressed after the injection of TTX. Conclusions: The functional changes of the retina either by focal or diffuse electrical stimulation were successfully detected by optical imaging of the retina. The contribution of retinal ganglion cells on RCs by ES was confirmed by TTX experiment. This method may be applied to the objective evaluation of the artificial retina.

  17. The torque-velocity relationship in large human muscles: maximum voluntary versus electrically stimulated behaviour.

    Science.gov (United States)

    Pain, Matthew T G; Young, Fraser; Kim, Jinwoo; Forrester, Stephanie E

    2013-02-22

    The in vivo maximum voluntary torque-velocity profile for large muscle groups differs from the in vitro tetanic profile with lower than expected eccentric torques. Using sub-maximal transcutaneous electrical stimulation has given torque-velocity profiles with an eccentric torque plateau ∼1.4 times the isometric value. This is closer to, but still less than, the in vitro tetanic profiles with plateaus between 1.5 and 1.9 times isometric. This study investigated the maximum voluntary and sub-maximum transcutaneous electrical stimulated torque-angle-angular velocity profiles for the knee extensors and flexors in a group of healthy males. Fifteen male subjects performed maximum voluntary and sub-maximum electrically stimulated (∼40% for extensors and ∼20% for flexors) eccentric and concentric knee extension and flexions on an isovelocity dynamometer at velocities ranging from ±50°s(-1) to ±400°s(-1). The ratio of peak eccentric to peak isometric torque (T(ecc)/T(0)) was compared between the maximum voluntary and electrically stimulated conditions for both extensors and flexors, and between muscle groups. Under maximum voluntary conditions the peak torque ratio, T(ecc)/T(0), remained close to 1 (0.9-1.2) while for the electrically stimulated conditions it was significantly higher (1.4-1.7; pmuscle groups have an intrinsic T(ecc)/T(0) comparable with in vitro muscle tests, and it can be ascertained from appropriate in vivo testing. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Effects of sensitive electrical stimulation based cueing in Parkinson's disease: a preliminary study

    Directory of Open Access Journals (Sweden)

    Benoît Sijobert

    2016-06-01

    Full Text Available This study aims to investigate the effect of a sensitive cueing on Freezing of Gait (FOG and gait disorders in subjects suffering from Parkinson’s disease (PD. 13 participants with Parkinson’s disease were equipped with an electrical stimulator and a foot mounted inertial measurement unit (IMU. An IMU based algorithm triggered in real time an electrical stimulus applied on the arch of foot at heel off detection. Starting from standing, subjects were asked to walk at their preferred speed on a path comprising 5m straight, u-turn and walk around tasks. Cueing globally decreased the time to achieve the different tasks in all the subjects. In “freezer” subjects, the time to complete the entire path was reduced by 19%. FOG events occurrence was lowered by 12% compared to baseline before and after cueing. This preliminary work showed a positive global effect of an electrical stimulation based cueing on gait and FOG in PD.

  19. Application of electrical stimulation for functional tissue engineering in vitro and in vivo

    Science.gov (United States)

    Radisic, Milica (Inventor); Park, Hyoungshin (Inventor); Langer, Robert (Inventor); Freed, Lisa (Inventor); Vunjak-Novakovic, Gordana (Inventor)

    2013-01-01

    The present invention provides new methods for the in vitro preparation of bioartificial tissue equivalents and their enhanced integration after implantation in vivo. These methods include submitting a tissue construct to a biomimetic electrical stimulation during cultivation in vitro to improve its structural and functional properties, and/or in vivo, after implantation of the construct, to enhance its integration with host tissue and increase cell survival and functionality. The inventive methods are particularly useful for the production of bioartificial equivalents and/or the repair and replacement of native tissues that contain electrically excitable cells and are subject to electrical stimulation in vivo, such as, for example, cardiac muscle tissue, striated skeletal muscle tissue, smooth muscle tissue, bone, vasculature, and nerve tissue.

  20. Towards an ankle neuroprosthesis for hybrid robotics: Concepts and current sources for functional electrical stimulation.

    Science.gov (United States)

    Casco, S; Fuster, I; Galeano, R; Moreno, J C; Pons, J L; Brunetti, F

    2017-07-01

    Hybrid rehabilitation robotics combine neuro-prosthetic devices (close-loop functional electrical stimulation systems) and traditional robotic structures and actuators to explore better therapies and promote a more efficient motor function recovery or compensation. Although hybrid robotics and ankle neuroprostheses (NPs) have been widely developed over the last years, there are just few studies on the use of NPs to electrically control both ankle flexion and extension to promote ankle recovery and improved gait patterns in paretic limbs. The aim of this work is to develop an ankle NP specifically designed to work in the field of hybrid robotics. This article presents early steps towards this goal and makes a brief review about motor NPs and Functional Electrical Stimulation (FES) principles and most common devices used to aid the ankle functioning during the gait cycle. It also shows a current sources analysis done in this framework, in order to choose the best one for this intended application.

  1. Electrical stimulation to conductive scaffold promotes axonal regeneration and remyelination in a rat model of large nerve defect.

    Directory of Open Access Journals (Sweden)

    Jinghui Huang

    Full Text Available BACKGROUND: Electrical stimulation (ES has been shown to promote nerve regeneration when it was applied to the proximal nerve stump. However, the possible beneficial effect of establishing a local electrical environment between a large nerve defect on nerve regeneration has not been reported in previous studies. The present study attempted to establish a local electrical environment between a large nerve defect, and examined its effect on nerve regeneration and functional recovery. METHODOLOGY/FINDINGS: In the present study, a conductive scaffold was constructed and used to bridge a 15 mm sciatic nerve defect in rats, and intermittent ES (3 V, 20 Hz was applied to the conductive scaffold to establish an electrical environment at the site of nerve defect. Nerve regeneration and functional recovery were examined after nerve injury repair and ES. We found that axonal regeneration and remyelination of the regenerated axons were significantly enhanced by ES which was applied to conductive scaffold. In addition, both motor and sensory functional recovery was significantly improved and muscle atrophy was partially reversed by ES localized at the conductive scaffold. Further investigations showed that the expression of S-100, BDNF (brain-derived neurotrophic factor, P0 and Par-3 was significantly up-regulated by ES at the conductive scaffold. CONCLUSIONS/SIGNIFICANCE: Establishing an electrical environment with ES localized at the conductive scaffold is capable of accelerating nerve regeneration and promoting functional recovery in a 15 mm nerve defect in rats. The findings provide new directions for exploring regenerative approaches to achieve better functional recovery in the treatment of large nerve defect.

  2. Effect of electrical stimulation of hamstrings and L3/4 dermatome on gait in spinal cord injury

    NARCIS (Netherlands)

    van der Salm, Arjan; Veltink, Petrus H.; Hermens, Hermanus J.; Nene, A.V.; IJzerman, Maarten Joost

    2006-01-01

    Objective. To determine the effect of electrical stimulation of hamstrings and L3/4 dermatome on the swing phase of gait. Materials and Methods. Five subjects with incomplete spinal cord injury (SCI) with spasticity were included. Two electrical stimulation methods were investigated, i.e.,

  3. Reliability of solid-state lighting electrical drivers subjected to WHTOL accelerated aging

    Energy Technology Data Exchange (ETDEWEB)

    Lall, Pradeep; Sakalauku, Peter; Davis, Lynn

    2014-05-27

    An investigation of a solid-state lighting (SSL) luminaire with the focus on the electronic driver which has been exposed to a standard wet hot temperature operating life (WHTOL) of 85% RH and 85°C in order to assess reliability of prolonged exposer to a harsh environment has been conducted. SSL luminaires are beginning introduced as head lamps in some of today's luxury automobiles and may also be fulfilling a variety of important outdoor applications such as overhead street lamps, traffic signals and landscape lighting. SSL luminaires in these environments are almost certain to encounter excessive moisture from humidity and high temperatures for a persistent period of time. The lack of accelerated test methods for LEDs to assess long-term reliability prior to introduction into the marketplace, a need for SSL physics based PHM modeling indicators for assessment and prediction of LED life, as well as the U.S. Department of Energy's R&D roadmap to replace todays lighting with SSL luminaires makes it important to increase the understanding of the reliability of SSL devices, specifically, in harsh environment applications. In this work, a set of SSL electrical drivers were investigated to determine failure mechanisms that occur during prolonged harsh environment applications. Each driver consists of four aluminum electrolytic capacitors (AECs) of three different types and was considered the weakest component inside the SSL electrical driver. The reliability of the electrical driver was assessed by monitoring the change in capacitance and the change in equivalent series resistance for each AEC, as well as monitoring the luminous flux of the SSL luminaire or the output of the electrical driver. The luminous flux of a pristine SSL electrical driver was also monitored in order to detect minute changes in the electrical drivers output and to aid in the investigation of the SSL luminaires reliability. The failure mechanisms of the electrical drivers have been

  4. Electrical Stimulation of Visual Cortex: Relevance for the Development of Visual Cortical Prosthetics.

    Science.gov (United States)

    Bosking, William H; Beauchamp, Michael S; Yoshor, Daniel

    2017-09-15

    Electrical stimulation of the cerebral cortex is a powerful tool for exploring cortical function. Stimulation of early visual cortical areas is easily detected by subjects and produces simple visual percepts known as phosphenes. A device implanted in visual cortex that generates patterns of phosphenes could be used as a substitute for natural vision in blind patients. We review the possibilities and limitations of such a device, termed a visual cortical prosthetic. Currently, we can predict the location and size of phosphenes produced by stimulation of single electrodes. A functional prosthetic, however, must produce spatial temporal patterns of activity that will result in the perception of complex visual objects. Although stimulation of later visual cortical areas alone usually does not lead to a visual percept, it can alter visual perception and the performance of visual behaviors, and training subjects to use signals injected into these areas may be possible.

  5. Non-invasive electrical and magnetic stimulation of the brain, spinal cord, roots and peripheral nerves

    DEFF Research Database (Denmark)

    Rossini, P M; Burke, D; Chen, R

    2015-01-01

    These guidelines provide an up-date of previous IFCN report on "Non-invasive electrical and magnetic stimulation of the brain, spinal cord and roots: basic principles and procedures for routine clinical application" (Rossini et al., 1994). A new Committee, composed of international experts, some...... theoretical, physiological and practical aspects of non-invasive stimulation of brain, spinal cord, nerve roots and peripheral nerves in the light of more updated knowledge, and include some recent extensions and developments....... of whom were in the panel of the 1994 "Report", was selected to produce a current state-of-the-art review of non-invasive stimulation both for clinical application and research in neuroscience. Since 1994, the international scientific community has seen a rapid increase in non-invasive brain stimulation...

  6. Electrical stimulation of dog pudendal nerve regulates the excitatory pudendal-to-bladder reflex

    Directory of Open Access Journals (Sweden)

    Yan-he Ju

    2016-01-01

    Full Text Available Pudendal nerve plays an important role in urine storage and voiding. Our hypothesis is that a neuroprosthetic device placed in the pudendal nerve trunk can modulate bladder function after suprasacral spinal cord injury. We had confirmed the inhibitory pudendal-to-bladder reflex by stimulating either the branch or the trunk of the pudendal nerve. This study explored the excitatory pudendal-to-bladder reflex in beagle dogs, with intact or injured spinal cord, by electrical stimulation of the pudendal nerve trunk. The optimal stimulation frequency was approximately 15-25 Hz. This excitatory effect was dependent to some extent on the bladder volume. We conclude that stimulation of the pudendal nerve trunk is a promising method to modulate bladder function.

  7. Accelerated Aging of Lithium-Ion Batteries based on Electric Vehicle Mission Profile

    DEFF Research Database (Denmark)

    Stroe, Daniel-Ioan; Swierczynski, Maciej Jozef; Kær, Søren Knudsen

    2017-01-01

    Electric vehicles (EVs) represent one of the solutions for reducing the carbon emissions worldwide. Even though EVs have recently gained more and more popularity, their adoption at a large scale is mainly prevented by several factors, such as range anxiety and battery degradation. The range...... and internal resistance increase (power decrease), by performing laboratory accelerated ageing tests for a period of eleven months. To perform this analysis, we used a standardized driving cycle – the Worldwide harmonized Light vehicles Test Cycle (WLTC) and a real-life temperature profile, characteristic...

  8. Scaling of the Longitudinal Electric Field and Transformer Ratio in a Nonlinear Plasma Wakefield Accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Blumenfeld, I.; /SLAC; Clayton, C.E.; /UCLA; Decker, F.J.; Hogan, M.J.; /SLAC; Huang, C.; /UCLA; Ischebeck, R.; Iverson, R.H.; /SLAC; Joshi, C.; /UCLA; Katsouleas, T.; /Southern California U.; Kirby, N.; /SLAC; Lu, W.; Marsh, K.A.; Mori, W.B.; /UCLA; Muggli, P.; Oz, E.; /Southern California U.; Siemann, R.H.; Walz, D.R.; /SLAC; Zhou, M.; /UCLA

    2012-06-12

    The scaling of the two important figures of merit, the transformer ratio T and the longitudinal electric field E{sub z}, with the peak drive-bunch current I{sub p}, in a nonlinear plasma wakefield accelerator is presented for the first time. The longitudinal field scales as I{sub P}{sup 0.623{+-}0.007}, in good agreement with nonlinear wakefield theory ({approx}I{sub P}{sup 0.5}), while the unloaded transformer ratio is shown to be greater than unity and scales weakly with the bunch current. The effect of bunch head erosion on both parameters is also discussed.

  9. Scaling of the longitudinal electric field and transformer ratio in a nonlinear plasma wakefield accelerator

    Directory of Open Access Journals (Sweden)

    I. Blumenfeld

    2010-11-01

    Full Text Available The scaling of the two important figures of merit, the transformer ratio T and the longitudinal electric field E_{z}, with the peak drive-bunch current I_{p}, in a nonlinear plasma wakefield accelerator is presented for the first time. The longitudinal field scales as I_{P}^{0.623±0.007}, in good agreement with nonlinear wakefield theory (∼I_{P}^{0.5}, while the unloaded transformer ratio is shown to be greater than unity and scales weakly with the bunch current. The effect of bunch head erosion on both parameters is also discussed.

  10. In situ electric fields causing electro-stimulation from conductor contact of charged human.

    Science.gov (United States)

    Nagai, Toshihiro; Hirata, Akimasa

    2010-08-01

    Contact currents flow from/into a human body when touching an object such as a metal structure with a different electric potential. These currents can stimulate muscle and peripheral nerves. In this context, computational analyses of in situ electric fields caused by the contact current have been performed, while their effectiveness for transient contact currents has not well been investigated. In the present study, using an anatomically based human model, a dispersive finite-difference time-domain model was utilised to computed transient contact current and in situ electric fields from a charged human. Computed in situ electric fields were highly localised in the hand. In order to obtain an insight into the relationship between in situ electric field and electro-stimulation, cell-maximum and 5-mm averaged in situ electric fields were computed and compared with strength-duration curves. The comparison suggests that both measures could be larger than thresholds derived from the strength-duration curves with parameters used in previous studies.

  11. On the performance of accelerated particle swarm optimization for charging plug-in hybrid electric vehicles

    Directory of Open Access Journals (Sweden)

    Imran Rahman

    2016-03-01

    Full Text Available Transportation electrification has undergone major changes since the last decade. Success of smart grid with renewable energy integration solely depends upon the large-scale penetration of plug-in hybrid electric vehicles (PHEVs for a sustainable and carbon-free transportation sector. One of the key performance indicators in hybrid electric vehicle is the State-of-Charge (SoC which needs to be optimized for the betterment of charging infrastructure using stochastic computational methods. In this paper, a newly emerged Accelerated particle swarm optimization (APSO technique was applied and compared with standard particle swarm optimization (PSO considering charging time and battery capacity. Simulation results obtained for maximizing the highly nonlinear objective function indicate that APSO achieves some improvements in terms of best fitness and computation time.

  12. Physiological processes non-linearly affect electrophysiological recordings during transcranial electric stimulation.

    Science.gov (United States)

    Noury, Nima; Hipp, Joerg F; Siegel, Markus

    2016-10-15

    Transcranial electric stimulation (tES) is a promising tool to non-invasively manipulate neuronal activity in the human brain. Several studies have shown behavioral effects of tES, but stimulation artifacts complicate the simultaneous investigation of neural activity with EEG or MEG. Here, we first show for EEG and MEG, that contrary to previous assumptions, artifacts do not simply reflect stimulation currents, but that heartbeat and respiration non-linearly modulate stimulation artifacts. These modulations occur irrespective of the stimulation frequency, i.e. during both transcranial alternating and direct current stimulations (tACS and tDCS). Second, we show that, although at first sight previously employed artifact rejection methods may seem to remove artifacts, data are still contaminated by non-linear stimulation artifacts. Because of their complex nature and dependence on the subjects' physiological state, these artifacts are prone to be mistaken as neural entrainment. In sum, our results uncover non-linear tES artifacts, show that current techniques fail to fully remove them, and pave the way for new artifact rejection methods. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. The interactions between different tastes on initiation of reflex swallow elicited by electrical stimulation in humans.

    Science.gov (United States)

    Otake, Masanori; Kurose, Masayuki; Uchida, Yoshiaki; Hasegawa, Mana; Yamada, Yoshiaki; Saito, Isao; Yamamura, Kensuke

    2016-09-01

    The act of eating is a source of pleasure for people and is a major factor in maintaining a good quality of life. Several types of products for dysphagia patients are available to decrease aspiration of food that often accompanies daily food intake. The final goal of these products is to improve the ease of forming a food bolus and/or the safety of the swallowing process; however, tastes of products are not a major concern with initiation of swallowing. In the present study, we investigated the effect of bitter taste stimuli (quinine) and the combination of quinine and umami (monosodium glutamate: MSG) applied to the oropharynx on reflex swallows evoked by electrical stimulation to the oropharyngeal mucosa. Each of the distilled water (DW), quinine and quinine-MSG mixture solution (volume of each solutions, 100 µl) was applied 1 s prior to electrical stimulation. No swallow was evoked when each of the solutions was applied without electrical stimulation. The application of DW and lower concentration of quinine (<100 µM) did not affect the latency of reflex swallow, but 100 µM quinine application increased the latency of the reflex swallow. In addition, application of quinine-MSG mixture solution counteracted the increase in latency induced by quinine application alone. These findings suggest that MSG enhances the initiation of swallowing along with its well-known increase in appetite stimulation. Adding MSG might be effective when creating food to promote swallowing.

  14. Efficacy of Carcass Electrical Stimulation in Meat Quality Enhancement: A Review

    Directory of Open Access Journals (Sweden)

    Kazeem Dauda Adeyemi

    2014-03-01

    Full Text Available The use of electrical stimulation (ES as a management tool to improve meat quality and efficiency of meat processing is reviewed. The basis of the efficacy of ES is its ability to fast track postmortem glycolysis, which in turn stimulates myriad histological, physical, biochemical, biophysical and physiological changes in the postmortem muscle. Electrical stimulation hastens the onset and resolution of rigor mortis thereby reducing processing time and labor and plays a vital role in improving meat tenderness and other meat quality traits. However, ES may have negative impacts on some meat quality traits such as color stability and water holding capacity in some animals. Electrical stimulation is not an end in itself. In order to achieve the desired benefits from its application, the technique must be properly used in conjunction with various intricate antemortem, perimortem and postmortem management practices. Despite extensive research on ES, the fundamental mechanisms and the appropriate commercial applications remained obscured. In addition, muscles differ in their response to ES. Thus, elementary knowledge of the various alterations with respect to muscle type is needed in order to optimize the effectiveness of ES in the improvement of meat quality.

  15. Efficacy of carcass electrical stimulation in meat quality enhancement: a review.

    Science.gov (United States)

    Adeyemi, Kazeem Dauda; Sazili, Awis Qurni

    2014-03-01

    The use of electrical stimulation (ES) as a management tool to improve meat quality and efficiency of meat processing is reviewed. The basis of the efficacy of ES is its ability to fast track postmortem glycolysis, which in turn stimulates myriad histological, physical, biochemical, biophysical and physiological changes in the postmortem muscle. Electrical stimulation hastens the onset and resolution of rigor mortis thereby reducing processing time and labor and plays a vital role in improving meat tenderness and other meat quality traits. However, ES may have negative impacts on some meat quality traits such as color stability and water holding capacity in some animals. Electrical stimulation is not an end in itself. In order to achieve the desired benefits from its application, the technique must be properly used in conjunction with various intricate antemortem, perimortem and postmortem management practices. Despite extensive research on ES, the fundamental mechanisms and the appropriate commercial applications remained obscured. In addition, muscles differ in their response to ES. Thus, elementary knowledge of the various alterations with respect to muscle type is needed in order to optimize the effectiveness of ES in the improvement of meat quality.

  16. Effect of stress induced by electrical stimulation of the hypothalamus on the electrical stability of the heart in rabbits.

    Science.gov (United States)

    Kashtanov, Sergei I; Mezentseva, Larisa V; Zvyagintseva, Marina A; Kosharskaja, Irina L; Sudakov, Konstantin V

    2004-09-01

    The influence of stress on cardiac electrical stability (CES) and chaotic dynamics of the electrical activity of the heart was studied in acute and chronic experiments in rabbits. Stress was caused by 2-3 h daily immobilization of the animals with electrical stimulation of emotiogenic centers of the hypothalamus through implanted electrodes. CES was estimated by the thresholds for ventricular arrhythmia: paroxysmal ventricular tachycardia, repeated ventricular extrasystoles and ventricular fibrillation (VF). The results showed: (i) CES in stressed rabbits was decreased significantly compared with controls; (ii) the level of chaos at the onset of VF in stressed rabbits was increased significantly compared with controls; (iii) heart rate of stressed rabbits was significantly greater than in controls; (iv) changes in CES parameters depended on whether stress was acute or chronic; (v) acute stress promoted transition of spontaneously reversible VF into spontaneously irreversible VF. Thus, stress increased the degree of disorganization of heart electrical activity and also decreased its electrical stability. The experiments indicate that stress is a destabilizing factor influencing the reversibility of heart rate disorders. The probability of such reversibility depends on whether stress is acute or chronic: acute stress is more likely to lead to irreversible spontaneous VF.

  17. Differential responses to high-frequency electrical stimulation in ON and OFF retinal ganglion cells

    Science.gov (United States)

    Twyford, Perry; Cai, Changsi; Fried, Shelley

    2014-04-01

    Objective. The field of retinal prosthetics for artificial vision has advanced considerably in recent years, however clinical outcomes remain inconsistent. The performance of retinal prostheses is likely limited by the inability of electrical stimuli to preferentially activate different types of retinal ganglion cell (RGC). Approach. Here we examine the response of rabbit RGCs to high-frequency stimulation, using biphasic pulses applied at 2000 pulses per second. Responses were recorded using cell-attached patch clamp methods, and stimulation was applied epiretinally via a small cone electrode. Main results. When prolonged stimulus trains were applied to OFF-brisk transient (BT) RGCs, the cells exhibited a non-monotonic relationship between response strength and stimulus amplitude; this response pattern was different from those elicited previously by other electrical stimuli. When the amplitude of the stimulus was modulated transiently from a non-zero baseline amplitude, ON-BT and OFF-BT cells exhibited different activity patterns: ON cells showed an increase in activity while OFF cells exhibited a decrease in activity. Using a different envelope to modulate the amplitude of the stimulus, we observed the opposite effect: ON cells exhibited a decrease in activity while OFF cells show an increase in activity. Significance. As ON and OFF RGCs often exhibit opposing activity patterns in response to light stimulation, this work suggests that high-frequency electrical stimulation of RGCs may be able to elicit responses that are more physiological than traditional pulsatile stimuli. Additionally, the prospect of an electrical stimulus capable of cell-type specific selective activation has broad applications throughout the fields of neural stimulation and neuroprostheses.

  18. In vitro effect of direct current electrical stimulation on rat mesenchymal stem cells

    Directory of Open Access Journals (Sweden)

    Sahba Mobini

    2017-01-01

    Full Text Available Background Electrical stimulation (ES has been successfully used to treat bone defects clinically. Recently, both cellular and molecular approaches have demonstrated that ES can change cell behavior such as migration, proliferation and differentiation. Methods In the present study we exposed rat bone marrow- (BM- and adipose tissue- (AT- derived mesenchymal stem cells (MSCs to direct current electrical stimulation (DC ES and assessed temporal changes in osteogenic differentiation. We applied 100 mV/mm of DC ES for 1 h per day for three, seven and 14 days to cells cultivated in osteogenic differentiation medium and assessed viability and calcium deposition at the different time points. In addition, expression of osteogenic genes, Runx2, Osteopontin, and Col1A2 was assessed in BM- and AT-derived MSCs at the different time points. Results Results showed that ES changed osteogenic gene expression patterns in both BM- and AT-MSCs, and these changes differed between the two groups. In BM-MSCs, ES caused a significant increase in mRNA levels of Runx2, Osteopontin and Col1A2 at day 7, while in AT-MSCs, the increase in Runx2 and Osteopontin expression were observed after 14 days of ES. Discussion This study shows that rat bone marrow- and adipose tissue-derived stem cells react differently to electrical stimuli, an observation that could be important for application of electrical stimulation in tissue engineering.

  19. Electric field distribution in a finite-volume head model of deep brain stimulation.

    Science.gov (United States)

    Grant, Peadar F; Lowery, Madeleine M

    2009-11-01

    This study presents a whole-head finite element model of deep brain stimulation to examine the effect of electrical grounding, the finite conducting volume of the head, and scalp, skull and cerebrospinal fluid layers. The impedance between the stimulating and reference electrodes in the whole-head model was found to lie within clinically reported values when the reference electrode was incorporated on a localized surface in the model. Incorporation of the finite volume of the head and inclusion of surrounding outer tissue layers reduced the magnitude of the electric field and activating function by approximately 20% in the region surrounding the electrode. Localized distortions of the electric field were also observed when the electrode was placed close to the skull. Under bipolar conditions the effect of the finite conducting volume was shown to be negligible. The results indicate that, for monopolar stimulation, incorporation of the finite volume and outer tissue layers can alter the magnitude of the electric field and activating function when the electrode is deep within the brain, and may further affect the shape if the electrode is close to the skull.

  20. Electrical Stimulation of Artificial Heart Muscle: A Look Into the Electrophysiologic and Genetic Implications.

    Science.gov (United States)

    Mohamed, Mohamed A; Islas, Jose F; Schwartz, Robert J; Birla, Ravi K

    Development of tissue-engineered hearts for treatment of myocardial infarction or biologic pacemakers has been hindered by the production of mostly arrhythmic or in-synergistic constructs. Electrical stimulation (ES) of these constructs has been shown to produce tissues with greater twitch force and better adrenergic response. To further our understanding of the mechanisms underlying the effect of ES, we fabricated a bioreactor capable of delivering continuous or intermittent waveforms of various types to multiple constructs simultaneously. In this study, we examined the effect of an intermittent biphasic square wave on our artificial heart muscle (AHM) composed of neonatal rat cardiac cells and fibrin gel. Twitch forces, spontaneous contraction rates, biopotentials, gene expression profiles, and histologic observations were examined for the ES protocol over a 12 day culture period. We demonstrate improved consistency between samples for twitch force and contraction rate, and higher normalized twitch force amplitudes for electrically stimulated AHMs. Improvements in electrophysiology within the AHM were noted by higher conduction velocities and lower latency in electrical response for electrically stimulated AHMs. Genes expressing key electrophysiologic and structural markers peaked at days 6 and 8 of culture, only a few days after the initiation of ES. These results may be used for optimization strategies to establish protocols for producing AHMs capable of replacing damaged heart tissue in either a contractile or electrophysiologic capacity. Optimized AHMs can lead to alternative treatments to heart failure and alleviate the limited donor supply crisis.

  1. A multi-pad electrode based functional electrical stimulation system for restoration of grasp

    Directory of Open Access Journals (Sweden)

    Malešević Nebojša M

    2012-09-01

    Full Text Available Abstract Background Functional electrical stimulation (FES applied via transcutaneous electrodes is a common rehabilitation technique for assisting grasp in patients with central nervous system lesions. To improve the stimulation effectiveness of conventional FES, we introduce multi-pad electrodes and a new stimulation paradigm. Methods The new FES system comprises an electrode composed of small pads that can be activated individually. This electrode allows the targeting of motoneurons that activate synergistic muscles and produce a functional movement. The new stimulation paradigm allows asynchronous activation of motoneurons and provides controlled spatial distribution of the electrical charge that is delivered to the motoneurons. We developed an automated technique for the determination of the preferred electrode based on a cost function that considers the required movement of the fingers and the stabilization of the wrist joint. The data used within the cost function come from a sensorized garment that is easy to implement and does not require calibration. The design of the system also includes the possibility for fine-tuning and adaptation with a manually controllable interface. Results The device was tested on three stroke patients. The results show that the multi-pad electrodes provide the desired level of selectivity and can be used for generating a functional grasp. The results also show that the procedure, when performed on a specific user, results in the preferred electrode configuration characteristics for that patient. The findings from this study are of importance for the application of transcutaneous stimulation in the clinical and home environments.

  2. Direct and crossed effects of somatosensory electrical stimulation on motor learning and neuronal plasticity in humans.

    Science.gov (United States)

    Veldman, M P; Zijdewind, I; Solnik, S; Maffiuletti, N A; Berghuis, K M M; Javet, M; Négyesi, J; Hortobágyi, T

    2015-12-01

    Sensory input can modify voluntary motor function. We examined whether somatosensory electrical stimulation (SES) added to motor practice (MP) could augment motor learning, interlimb transfer, and whether physiological changes in neuronal excitability underlie these changes. Participants (18-30 years, n = 31) received MP, SES, MP + SES, or a control intervention. Visuomotor practice included 300 trials for 25 min with the right-dominant wrist and SES consisted of weak electrical stimulation of the radial and median nerves above the elbow. Single- and double-pulse transcranial magnetic stimulation (TMS) metrics were measured in the intervention and non-intervention extensor carpi radialis. There was 27 % motor learning and 9 % (both p Motor practice and SES each can produce motor learning and interlimb transfer and are likely to be mediated by different mechanisms. The results provide insight into the physiological mechanisms underlying the effects of MP and SES on motor learning and cortical plasticity and show that these mechanisms are likely to be different for the trained and stimulated motor cortex and the non-trained and non-stimulated motor cortex.

  3. Intraoperative direct electrical stimulations of central nervous system during surgery of gliomas near eloquent areas

    Directory of Open Access Journals (Sweden)

    WANG Wei-min

    2012-12-01

    Full Text Available Objective To report our experiences of direct cortical stimulation in surgery of gliomas located in eloquent areas. Methods Clinical data of 157 patients with gliomas underwent awake craniotomy with the direct electrical stimulation for functional mapping of the eloquent areas were analysed retrospectively. Results Negative cortical stimulation was found in 4 patients, and positive cortical stimulation was achieved in 153 patients (97.45% . Four hundred and ninty -six cortical sites in 139 patients were detected for motor response by direct electrical stimulation, 70 sites in 21 patients for sensory, 112 sites in 91 patients for language (such as counting and naming. The positive areas of counting disturbance were mainly seen at the lower part of left precentral gyri operculum of left inferior frontal gyri, triangular part of left inferior frontal gyri, posterior part of left middle frontal gyri, and posterior part of left superior frontal gyri. Postoperative MRI showed 92 patients (58.60% achieved total resection, 55 cases (35.03% subtotal and 10 cases (6.37% partial. One hundred and ten patients (70.06% were diagnosed as having low grade glimas, including 71 cases of astrocytoma, 26 cases of oligodendroglioma, and 13 cases of mixed astro ? oligodendroglioma, 47 patients (29.94% were high grade gliomas, including 19 cases of glioblastoma, 15 cases of anaplastic astrocytoma, and 13 cases of anaplastic oligodendroglioma. After operation 53 patients (33.76% occurred transient postoperative paralysis, 39 patients (24.84% transient language disturbance and 4 patients (2.55% permanent neurological deficits. Conclusion Intraoperative direct electrical stimulation is a reliable, precise and safety method for functional mapping of the eloquent areas. This technique allows us to achieve 'maximal safety resection' in glioma surgery.

  4. Effectiveness of transcutaneous electrical nerve stimulation and microcurrent electrical nerve stimulation in bruxism associated with masticatory muscle pain--a comparative study.

    Science.gov (United States)

    Rajpurohit, Bharat; Khatri, Subhash M; Metgud, Deepa; Bagewadi, Anjana

    2010-01-01

    To compare the effectiveness of transcutaneous electrical nerve stimulation (TENS) and microcurrent electrical nerve stimulation (MENS) on masticatory muscles pain bruxism patient. A total of 60 subjects with the clinical diagnosis of bruxism were randomly allocated to two study groups. Group A received TENS (50 Hz, pulse width 0.5 mSec, intensity 0-60 mA for 20 minutes for a period of seven days) and Group B received MENS (0.5 Hz, intensity 1,000 muA for 20 minutes for a period of seven days). The outcome measures were assessed in term of Visual Analog Scale (VAS) and digital pressometer of 2 Kgf. The study showed significant change in intensity of pain as per VAS score ( P

  5. Effectiveness of transcutaneous electrical nerve stimulation and microcurrent electrical nerve stimulation in bruxism associated with masticatory muscle pain - A comparative study

    Directory of Open Access Journals (Sweden)

    Rajpurohit Bharat

    2010-01-01

    Full Text Available Objectives: To compare the effectiveness of transcutaneous electrical nerve stimulation (TENS and microcurrent electrical nerve stimulation (MENS on masticatory muscles pain bruxism patient. Materials and Methods : A total of 60 subjects with the clinical diagnosis of bruxism were randomly allocated to two study groups. Group A received TENS (50 Hz, pulse width 0.5 mSec, intensity 0-60 mA for 20 minutes for a period of seven days and Group B received MENS (0.5 Hz, intensity 1,000 μA for 20 minutes for a period of seven days. The outcome measures were assessed in term of Visual Analog Scale (VAS and digital pressometer of 2 Kgf. Results : The study showed significant change in intensity of pain as per VAS score ( P ≤ 0.0001 and tenderness as per digital pressometer ( P ≤ 0.0001. Conclusion : MENS could be used as an effective pain-relieving adjunct to TENS in the treatment of masticatory muscle pain due to bruxism.

  6. The acute effects of accelerated repetitive Transcranial Magnetic Stimulation on suicide risk in unipolar depression: preliminary results.

    Science.gov (United States)

    Desmyter, Stefanie; Duprat, Romain; Baeken, Chris; Bijttebier, Stijn; van Heeringen, Kees

    2014-11-01

    Suicide is a major health concern. Effective acute interventions are lacking. Recent studies have suggested an acute decrease of suicidal ideations following repetitive Transcranial Magnetic Stimulation (rTMS). However, placebo effects could not be excluded. We aimed to evaluate the acute effect of accelerated intermittent theta burst stimulation (TBS) on suicide risk in depression. In 12 suicidal therapy-resistant depressed patients accelerated intermittent TBS was delivered on the left dorsolateral prefrontal cortex in a randomized, sham-controlled cross-over fashion. Patients received 20 sessions spread over 4 days. The change in severity of suicidal ideation was measured by the Beck Scale of Suicidal Ideation (SSI) before and after treatment. We found a significant decrease of SSI score over time; unrelated to active or sham stimulation. Furthermore, the attenuation of suicidal thinking was not merely related to depression severity changes caused by TBS. Accelerated TBS treatment in depressed suicidal patients was found to be safe and well tolerated and may have the potential to acutely decrease suicidal ideations. However, the efficacy compared to sham has not yet been proven and further sham-controlled research including longer follow-up is needed to substantiate these preliminary findings.

  7. Behavioral responses of deafened guinea pigs to intracochlear electrical stimulation: a new rapid psychophysical procedure.

    Science.gov (United States)

    Agterberg, Martijn J H; Versnel, Huib

    2014-07-01

    In auditory research the guinea pig is often preferred above rats and mice because of the easily accessible cochlea and because the frequency range of its hearing is more comparable to that of humans. Studies of the guinea-pig auditory system primarily apply histological and electrophysiological measures. Behavioral animal paradigms, in particular in combination with these histological and electrophysiological methods, are necessary in the development of new therapeutic interventions. However, the guinea pig is not considered an attractive animal for behavioral experiments. Therefore, the purpose of this study was to develop a behavioral task suitable for guinea pigs, that can be utilized in cochlear-implant related research. Guinea pigs were trained in a modified shuttle-box in which a stream of air was used as unconditioned stimulus (UCS). A stream of air was preferred over conventionally used methods as electric foot-shocks since it produces less stress, which is a confounding factor in behavioral experiments. Hearing guinea pigs were trained to respond to acoustic stimuli. They responded correctly within only five sessions of ten minutes. The animals maintained their performance four weeks after the right cochlea was implanted with an electrode array. After systemic deafening, the animals responded in the first session immediately to intracochlear electrical stimulation. These responses were not affected by daily chronic electrical stimulation (CES). In conclusion, the present study demonstrates that guinea pigs can be trained relatively fast to respond to acoustic stimuli, and that the training has a lasting effect, which generalizes to intracochlear electrical stimulation after deafening. Furthermore, it demonstrates that bilaterally deafened guinea pigs with substantial (∼50%) loss of spiral ganglion cells (SGCs), detect intracochlear electrical stimulation. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Parallel PWTD-Accelerated Explicit Solution of the Time Domain Electric Field Volume Integral Equation

    KAUST Repository

    Liu, Yang

    2016-03-25

    A parallel plane-wave time-domain (PWTD)-accelerated explicit marching-on-in-time (MOT) scheme for solving the time domain electric field volume integral equation (TD-EFVIE) is presented. The proposed scheme leverages pulse functions and Lagrange polynomials to spatially and temporally discretize the electric flux density induced throughout the scatterers, and a finite difference scheme to compute the electric fields from the Hertz electric vector potentials radiated by the flux density. The flux density is explicitly updated during time marching by a predictor-corrector (PC) scheme and the vector potentials are efficiently computed by a scalar PWTD scheme. The memory requirement and computational complexity of the resulting explicit PWTD-PC-EFVIE solver scale as ( log ) s s O N N and ( ) s t O N N , respectively. Here, s N is the number of spatial basis functions and t N is the number of time steps. A scalable parallelization of the proposed MOT scheme on distributed- memory CPU clusters is described. The efficiency, accuracy, and applicability of the resulting (parallelized) PWTD-PC-EFVIE solver are demonstrated via its application to the analysis of transient electromagnetic wave interactions on canonical and real-life scatterers represented with up to 25 million spatial discretization elements.

  9. Visualization of the electric field evoked by transcranial electric stimulation during a craniotomy using the finite element method.

    Science.gov (United States)

    Tomio, Ryosuke; Akiyama, Takenori; Horikoshi, Tomo; Ohira, Takayuki; Yoshida, Kazunari

    2015-12-30

    Transcranial MEP (tMEP) monitoring is more readily performed than cortical MEP (cMEP), however, tMEP is considered as less accurate than cMEP. The craniotomy procedure and changes in CSF levels must affect current spread. These changes can impair the accuracy. The aim of this study was to investigate the influence of skull deformation and cerebrospinal fluid (CSF) decrease on tMEP monitoring during frontotemporal craniotomy. We used the finite element method to visualize the electric field in the brain, which was generated by transcranial electric stimulation, using realistic 3-dimensional head models developed from T1-weighted images. Surfaces of 5 layers of the head were separated as accurately as possible. We created 3 brain types and 5 craniotomy models. The electric field in the brain radiates out from the cortex just below the electrodes. When the CSF layer is thick, a decrease in CSF volume and depression of CSF surface level during the craniotomy has a major impact on the electric field. When the CSF layer is thin and the distance between the skull and brain is short, the craniotomy has a larger effect on the electric field than the CSF decrease. So far no report in the literature the electric field during intraoperative tMEP using a 3-dimensional realistic head model. Our main finding was that the intensity of the electric field in the brain is most affected by changes in the thickness and volume of the CSF layer. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. [Clinical research of post-stroke insomnia treated with low-frequency electric stimulation at acupoints in the patients].

    Science.gov (United States)

    Tang, Lei; You, Fei; Ma, Chao-Yang

    2014-08-01

    To compare the difference in the clinical efficacy on post-stroke insomnia between the low-frequency electric stimulation at the acupoints and the conventional western medication. One hundred and twenty patients of post-stroke insomnia were randomized into a low-frequency electric stimulation group, a medication group and a placebo group, 40 cases in each one. In the low-frequency electric stimulation group, the low-frequency electric-pulsing apparatus was used at Dazhui (GV 14) and Shenshu (BL 23), once a day; the treatment of 15 days made one session and 2 sessions were required. In the medication group, estazolam was taken orally, 1 mg each time. In the placebo group, starch capsules were taken orally, 1 capsule each time. All the drugs were taken before sleep every night, continuously for 15 days as one session, and 2 sessions were required. PSQI changes and clinical efficacy were observed before and after treatment in each group. Pitlsburgh sleep quality index (PSQI) score was reduced in every group after treatment (all P electric stimulation group and medication group, the score was reduced much more significantly as compared with the placebo group (both P electric stimulation group, medication group and placebo group separately. The efficacy in the low-frequency electric stimulation group and medication group was better apparently than that in the placebo group (both P electric stimulation at the acupoints effectively and safely treats post-stroke insomnia and the efficacy of it is similar to that of estazolam.

  11. The effects of temperature changes on retinal ganglion cell responses to electrical stimulation.

    Science.gov (United States)

    Maturana, Matias I; Apollo, Nicholas V; Garrett, David J; Kameneva, Tatiana; Meffin, Hamish; Ibbotson, Michael R; Cloherty, Shaun L; Grayden, David B

    2015-01-01

    Little is known about how the retina's response to electrical stimulation is modified by temperatures. In vitro experiments are often used to inform in vivo studies, hence it is important to understand what changes occur at physiological temperature. To investigate this, we recorded from eight RGCs in vitro at three temperatures; room temperature (24°C), 30°C and 34°C. Results show that response latencies and thresholds are reduced, bursting spike rates in response to stimulation increases, and the spiking becomes more consistently locked to the stimulus at higher temperatures.

  12. Study of nerve fibers nature reinforcing duodenal contractions by electrical stimulation of sympathetic nerve

    Directory of Open Access Journals (Sweden)

    Sveshnikov D.S.

    2011-09-01

    Full Text Available The subject of the article is to investigate the mechanism of increased reactions by electrical stimulation of the sympathetic nerve. Materials and methods: Experiments on dogs have shown that stimulant reactions during blockade of a-adrenergic by phentolamine and (3-adrenergic receptors with propranolol were completely eliminated by lizer-gol —the blocker of 5-HT12-receptors. Results: Infusion of lizergol did not influence on duodenal motor activity and the function of the vagus nerve. Conclusion: Effector neuron is found out to be serotonergic and its action is provided by 5-HT1 2 receptors

  13. Managing equinus in children with cerebral palsy: electrical stimulation to strengthen the triceps surae muscle.

    Science.gov (United States)

    Carmick, J

    1995-11-01

    A new therapeutic proposal for the management of equinus in children with cerebral palsy is to strengthen the calf muscles instead of weakening them surgically. Prior research indicates that in children with cerebral palsy the triceps surae muscle is weak and needs strengthening. Neuromuscular electrical stimulation (NMES) was used as an adjunct to physical therapy. A portable NMES unit with a hand-held remote switch stimulated an active muscle gait cycle. Results are discussed for four children, who showed improved gait, balance, posture, active and passive ankle range of motion, and foot alignment. The toe walkers became plantigrade and the equinovalgus posture of the foot decreased. Spasticity did not increase.

  14. The morphological and molecular changes of brain cells exposed to direct current electric field stimulation.

    Science.gov (United States)

    Pelletier, Simon J; Lagacé, Marie; St-Amour, Isabelle; Arsenault, Dany; Cisbani, Giulia; Chabrat, Audrey; Fecteau, Shirley; Lévesque, Martin; Cicchetti, Francesca

    2014-12-07

    The application of low-intensity direct current electric fields has been experimentally used in the clinic to treat a number of brain disorders, predominantly using transcranial direct current stimulation approaches. However, the cellular and molecular changes induced by such treatment remain largely unknown. Here, we tested various intensities of direct current electric fields (0, 25, 50, and 100V/m) in a well-controlled in vitro environment in order to investigate the responses of neurons, microglia, and astrocytes to this type of stimulation. This included morphological assessments of the cells, viability, as well as shape and fiber outgrowth relative to the orientation of the direct current electric field. We also undertook enzyme-linked immunosorbent assays and western immunoblotting to identify which molecular pathways were affected by direct current electric fields. In response to direct current electric field, neurons developed an elongated cell body shape with neurite outgrowth that was associated with a significant increase in growth associated protein-43. Fetal midbrain dopaminergic explants grown in a collagen gel matrix also showed a reorientation of their neurites towards the cathode. BV2 microglial cells adopted distinct morphological changes with an increase in cyclooxygenase-2 expression, but these were dependent on whether they had already been activated with lipopolysaccharide. Finally, astrocytes displayed elongated cell bodies with cellular filopodia that were oriented perpendicularly to the direct current electric field. We show that cells of the central nervous system can respond to direct current electric fields both in terms of their morphological shape and molecular expression of certain proteins, and this in turn can help us to begin understand the mechanisms underlying the clinical benefits of direct current electric field. © The Author 2015. Published by Oxford University Press on behalf of CINP.

  15. Denervated muscles in humans: limitations and problems of currently used functional electrical stimulation training protocols.

    Science.gov (United States)

    Kern, Helmut; Hofer, Christian; Mödlin, Michaela; Forstner, Claudia; Raschka-Högler, Doris; Mayr, Winfried; Stöhr, Hans

    2002-03-01

    Prior clinical work showed that electrical stimulation therapy with exponential current is able to slow down atrophy and maintain the muscle during nonpermanent flaccid paralysis. However, exponential currents are not sufficient for long-term therapy of denervated degenerated muscles (DDMs). We initiated a European research project investigating the rehabilitation strategies in humans, but also studying the underlying basic scientific knowledge of muscle regeneration from satellite cells or myoblast activity in animal experiments. In our prior study, we were able to show that high-intensity stimulation of DDMs is possible. At the beginning of training, only single muscle twitches can be elicited by biphasic pulses with durations of 120-150 ms. Later, tetanic contraction of the muscle with special stimulation parameters (pulse duration of 30-50 ms, stimulation frequency of 16-25 Hz, pulse amplitudes of up to 250 mA) can improve the structural and metabolic state of the DDMs. Because there are no nerve endings for conduction of stimuli, large-size, anatomically shaped electrodes are used. This ensures an even contraction of the whole muscle. Contrary to the current clinical knowledge, we were able to stimulate and train denervated muscle 15-20 years after denervation. The estimated amount of muscle fibers that have to be restored is about 2-4 million fibers in each m. quadriceps. To rebuild such a large number of muscle fibers takes up to 3-4 years. Despite constant stimulation parameters and training protocols, there is a high variation in the developed contraction force and fatigue resistance of the muscle during the first years of functional electrical stimulation.

  16. Motor cortex electrical stimulation augments sprouting of the corticospinal tract and promotes recovery of motor function

    Directory of Open Access Journals (Sweden)

    Jason B Carmel

    2014-06-01

    Full Text Available The corticospinal system—with its direct spinal pathway, the corticospinal tract (CST—is the primary system for controlling voluntary movement. Our approach to CST repair after injury in mature animals was informed by our finding that activity drives establishment of connections with spinal cord circuits during postnatal development. After incomplete injury in maturity, spared CST circuits sprout and partially restore lost function. Our approach harnesses activity to augment this injury-dependent CST sprouting and to promote function. Lesion of the medullary pyramid unilaterally eliminates all CST axons from one hemisphere and allows examination of CST sprouting from the unaffected hemisphere. We discovered that ten days of electrical stimulation of either the spared CST or motor cortex induces CST axon sprouting that partially reconstructs the lost CST. Stimulation also leads to sprouting of the cortical projection to the magnocellular red nucleus, where the rubrospinal tract originates. Coordinated outgrowth of the CST and cortical projections to the red nucleus could support partial re-establishment of motor systems connections to the denervated spinal motor circuits. Stimulation restores skilled motor function in our animal model. Lesioned animals have a persistent forelimb deficit contralateral to pyramidotomy in the horizontal ladder task. Rats that received motor cortex stimulation either after acute or chronic injury showed a significant functional improvement that brought error rate to pre-lesion control levels. Reversible inactivation of the stimulated motor cortex reinstated the impairment demonstrating the importance of the stimulated system to recovery. Motor cortex electrical stimulation is an effective approach to promote spouting of spared CST axons. By optimizing activity-dependent sprouting in animals, we could have an approach that can be translated to the human for evaluation with minimal delay.

  17. Motor cortex electrical stimulation augments sprouting of the corticospinal tract and promotes recovery of motor function

    Science.gov (United States)

    Carmel, Jason B.; Martin, John H.

    2014-01-01

    The corticospinal system—with its direct spinal pathway, the corticospinal tract (CST) – is the primary system for controlling voluntary movement. Our approach to CST repair after injury in mature animals was informed by our finding that activity drives establishment of connections with spinal cord circuits during postnatal development. After incomplete injury in maturity, spared CST circuits sprout, and partially restore lost function. Our approach harnesses activity to augment this injury-dependent CST sprouting and to promote function. Lesion of the medullary pyramid unilaterally eliminates all CST axons from one hemisphere and allows examination of CST sprouting from the unaffected hemisphere. We discovered that 10 days of electrical stimulation of either the spared CST or motor cortex induces CST axon sprouting that partially reconstructs the lost CST. Stimulation also leads to sprouting of the cortical projection to the magnocellular red nucleus, where the rubrospinal tract originates. Coordinated outgrowth of the CST and cortical projections to the red nucleus could support partial re-establishment of motor systems connections to the denervated spinal motor circuits. Stimulation restores skilled motor function in our animal model. Lesioned animals have a persistent forelimb deficit contralateral to pyramidotomy in the horizontal ladder task. Rats that received motor cortex stimulation either after acute or chronic injury showed a significant functional improvement that brought error rate to pre-lesion control levels. Reversible inactivation of the stimulated motor cortex reinstated the impairment demonstrating the importance of the stimulated system to recovery. Motor cortex electrical stimulation is an effective approach to promote spouting of spared CST axons. By optimizing activity-dependent sprouting in animals, we could have an approach that can be translated to the human for evaluation with minimal delay. PMID:24994971

  18. Fast multigrid-based computation of the induced electric field for transcranial magnetic stimulation.

    Science.gov (United States)

    Laakso, Ilkka; Hirata, Akimasa

    2012-12-07

    In transcranial magnetic stimulation (TMS), the distribution of the induced electric field, and the affected brain areas, depends on the position of the stimulation coil and the individual geometry of the head and brain. The distribution of the induced electric field in realistic anatomies can be modelled using computational methods. However, existing computational methods for accurately determining the induced electric field in realistic anatomical models have suffered from long computation times, typically in the range of tens of minutes or longer. This paper presents a matrix-free implementation of the finite-element method with a geometric multigrid method that can potentially reduce the computation time to several seconds or less even when using an ordinary computer. The performance of the method is studied by computing the induced electric field in two anatomically realistic models. An idealized two-loop coil is used as the stimulating coil. Multiple computational grid resolutions ranging from 2 to 0.25 mm are used. The results show that, for macroscopic modelling of the electric field in an anatomically realistic model, computational grid resolutions of 1 mm or 2 mm appear to provide good numerical accuracy compared to higher resolutions. The multigrid iteration typically converges in less than ten iterations independent of the grid resolution. Even without parallelization, each iteration takes about 1.0 s or 0.1 s for the 1 and 2 mm resolutions, respectively. This suggests that calculating the electric field with sufficient accuracy in real time is feasible.

  19. Electric Stimulation at 448 kHz Promotes Proliferation of Human Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    María Luisa Hernández-Bule

    2014-11-01

    Full Text Available Background/Aims: Capacitive-resistive electric transfer (CRET is a non invasive electrothermal therapy that applies electric currents within the 400 kHz - 450 kHz frequency range to the treatment of musculoskeletal lesions. Evidence exists that electric currents and electric or magnetic fields can influence proliferative and/or differentiating processes involved in tissue regeneration. This work investigates proliferative responses potentially underlying CRET effects on tissue repair. Methods: XTT assay, flow cytometry, immunofluorescence and Western Blot analyses were conducted to asses viability, proliferation and differentiation of adipose-derived stem cells (ADSC from healthy donors, after short, repeated (5 m On/4 h Off in vitro stimulation with a 448-kHz electric signal currently used in CRET therapy, applied at a subthermal dose of 50 μA/mm2Results: The treatment induced PCNA and ERK1/2 upregulation, together with significant increases in the fractions of ADSC undergoing cycle phases S, G2 and M, and enhanced cell proliferation rate. This proliferative effect did not compromise the multipotential ability of ADSC for subsequent adipogenic, chondrogenic or osteogenic differentiation. Conclusions: These data identify cellular and molecular phenomena potentially underlying the response to CRET and indicate that CRET-induced lesion repair could be mediated by stimulation of the proliferation of stem cells present in the injured tissues.

  20. Electric stimulation at 448 kHz promotes proliferation of human mesenchymal stem cells.

    Science.gov (United States)

    Hernández-Bule, María Luisa; Paíno, Carlos Luis; Trillo, María Ángeles; Úbeda, Alejandro

    2014-01-01

    Capacitive-resistive electric transfer (CRET) is a non invasive electrothermal therapy that applies electric currents within the 400 kHz - 450 kHz frequency range to the treatment of musculoskeletal lesions. Evidence exists that electric currents and electric or magnetic fields can influence proliferative and/or differentiating processes involved in tissue regeneration. This work investigates proliferative responses potentially underlying CRET effects on tissue repair. XTT assay, flow cytometry, immunofluorescence and Western Blot analyses were conducted to asses viability, proliferation and differentiation of adipose-derived stem cells (ADSC) from healthy donors, after short, repeated (5 m On/4 h Off) in vitro stimulation with a 448-kHz electric signal currently used in CRET therapy, applied at a subthermal dose of 50 μA/mm(2) RESULTS: The treatment induced PCNA and ERK1/2 upregulation, together with significant increases in the fractions of ADSC undergoing cycle phases S, G2 and M, and enhanced cell proliferation rate. This proliferative effect did not compromise the multipotential ability of ADSC for subsequent adipogenic, chondrogenic or osteogenic differentiation. These data identify cellular and molecular phenomena potentially underlying the response to CRET and indicate that CRET-induced lesion repair could be mediated by stimulation of the proliferation of stem cells present in the injured tissues. © 2014 S. Karger AG, Basel.

  1. Isokinetic and isometric muscle strength combined with transcutaneous electrical muscle stimulation in primary fibromyalgia syndrome

    DEFF Research Database (Denmark)

    Jacobsen, Søren; Wildschiødtz, Gordon; Danneskiold-Samsøe, B

    1991-01-01

    with superimposed transcutaneous electrical stimulation. The examination protocol was repeated after 1 h of resting. Isokinetic and isometric muscle strength was found to be, respectively, 45% (p = 0.0001) and 44% (p = 0.0001) lower in the patient group compared to the healthy subjects. The frequency...... of superimposed twitches was 65% in the patient group and 15% in the control group (p = 0.003). Patients with primary fibromyalgia have a lower maximum voluntary muscle strength than expected. The increased presence of superimposed electrically elicited twitches during maximum voluntary contraction indicates...

  2. Fast Acceleration of ``Killer'' Electrons and Energetic Ions by Interplanetary Shock Stimulated ULF Waves in the Inner Magnetosphere

    Science.gov (United States)

    Zong, Q.

    2010-12-01

    Energetic electrons and ions in the Van Allen radiation belt are the number one space weather threat. How the energetic particles are accelerated in the Van Allen radiation belts is one of major problems in the space physics. Very Low Frequency (VLF) wave-particle interaction has been considered as one of primary electron acceleration mechanisms because electron cyclotron resonances can easily occur in the VLF frequency range. However, recently, by using four Cluster spacecraft observations, we have found that after interplanetary shocks impact on the Earth’s magnetosphere, the acceleration of the energetic electrons in the radiation belt started nearly immediately and lasted for a few hours. The time scale (a few days) for traditional acceleration mechanism of VLF wave-particle interaction, as proposed by Horne et al. [1], to accelerate electrons to relativistic energies is too long to explain the observations. It is further found that interplanetary shocks or solar wind pressure pulses with even small dynamic pressure change can play a non-negligible role in the radiation belt dynamics. Interplanetary shocks interact with and the Earth’s magnetosphere manifests many fundamental important space physics phenomena including energetic particle acceleration. The mechanism of fast acceleration of energetic electrons in the radiation belt response to interplanetary shock impact contains three contributing parts: (1) the initial adiabatic acceleration due to the strong shock-related magnetic field compression; (2) then followed by the drift-resonant acceleration with poloidal ULF waves excited at different L-shells; and (3) particle acceleration due to fast damping electric fields associated with ULF waves. Particles will have a net acceleration since particles in the second half circle will not lose all of the energy gained in the first half cycle. The results reported in this paper cast new lights on understanding the acceleration of energetic particles in the

  3. Synthesis of polypyrrole nanowires with positive effect on MC3T3-E1 cell functions through electrical stimulation.

    Science.gov (United States)

    He, Yuan; Wang, Shihui; Mu, Jing; Dai, Lingfeng; Zhang, Zhong; Sun, Yanan; Shi, Wei; Ge, Dongtao

    2017-02-01

    Conducting polymer polypyrrole (PPy) possesses good biocompatibility and conductivity and has been used as functional coatings in bone tissue regeneration. In this study, a cholic acid doped PPy nanowires (PPy NWs) coating was electrochemically polymerized on the surface of titanium (Ti). The porous intertwined PPy NWs coating exhibited excellent electrical conductivity and electrochemical activity, better hydrophilicity and higher surface energy. In vitro cell experiments demonstrated that the PPy NWs coating together with a 10μA substrate-mediate electrical stimulation (ES) was capable to positive regulate the functions of MC3T3-E1 such as cell adhesion, proliferation and differentiation. Further long-term functions of cell tests including alkaline phosphatase (ALP) activity, bone-carboxyglutamic acid-containing protein (BGP) and calcium deposition were all thoroughly increased. These confirmed that the combination of PPy NWs and ES could accelerate MC3T3-E1 cells mature and osteogenesis. Hence, the PPy NWs coating was an electro bioactive coating and may have potential applications in the treatment of bone damage repairing and regeneration with ES. Copyright © 2016. Published by Elsevier B.V.

  4. Simulation of the electrical field in equine larynx to optimize functional electrical stimulation in denervated musculus cricoarythenoideus dorsalis

    Directory of Open Access Journals (Sweden)

    Martin Reichel

    2014-03-01

    Full Text Available Distribution of the electrical field is very important to activate muscle and nerve cells properly. One therapeutic method to treat Recurrent Laryngeal Neuropathy (RLN in horses can be performed by Functional Electrical Stimulation (FES. Current method to optimize the stimulation effect is to use implanted quadripolar electrodes to the musculus cricoarythenoideus dorsalis (CAD and testing electrode configuration until best possible optimum is reached. For better understanding and finding of maximum possible activation of CAD a simulation model of the actual entire setting is currently in development. Therefore the geometric model is built from CT-data of a dissected larynx containing the quadripolar electrodes as well as fiducials for later data registration. The geometric model is the basis for a finite difference method containing of voxels with corresponding electrical conductivity of the different types of tissue due to threshold segmentation of the CT-data. Model validation can be done by the measurement of the 3D electrical potential distribution of a larynx positioned in an electrolytic tray. Finally, measured and calculated results have to be compared as well as further investigated. Preliminary results show, that changes of electrode as well as conductivity configuration leads to significant different voltage distributions and can be well presented by equipotential lines superimposed CT-slices – a Matlab graphical user interface visualizes the results in freely selectable slices of the 3D geometry. Voltage distribution along theoretically estimated fiber paths could be calculated as well as visualized. For further calculation of nerve or denervated muscle fiber activation and its optimization, real fiber paths have to be defined and referenced to the potential- and the CT-data.

  5. Simulation of the electrical field in equine larynx to optimize functional electrical stimulation in denervated musculus cricoarythenoideus dorsalis

    Directory of Open Access Journals (Sweden)

    Martin Reichel

    2014-09-01

    Full Text Available Distribution of the electrical field is very important to activate muscle and nerve cells properly. One therapeutic method to treat Recurrent Laryngeal Neuropathy (RLN in horses can be performed by Functional Electrical Stimulation (FES. Current method to optimize the stimulation effect is to use implanted quadripolar electrodes to the musculus cricoarythenoideus dorsalis (CAD and testing electrode configuration until best possible optimum is reached. For better understanding and finding of maximum possible activation of CAD a simulation model of the actual entire setting is currently in development. Therefore the geometric model is built from CT-data of a dissected larynx containing the quadripolar electrodes as well as fiducials for later data registration. The geometric model is the basis for a finite difference method containing of voxels with corresponding electrical conductivity of the different types of tissue due to threshold segmentation of the CT-data. Model validation can be done by the measurement of the 3D electrical potential distribution of a larynx positioned in an electrolytic tray. Finally, measured and calculated results have to be compared as well as further investigated. Preliminary results show, that changes of electrode as well as conductivity configuration leads to significant different voltage distributions and can be well presented by equipotential lines superimposed CT-slices – a Matlab graphical user interface visualizes the results in freely selectable slices of the 3D geometry. Voltage distribution along theoretically estimated fiber paths could be calculated as well as visualized. For further calculation of nerve or denervated muscle fiber activation and its optimization, real fiber paths have to be defined and referenced to the potential- and the CT-data.

  6. Simulation of the Electrical Field in Equine Larynx to Optimize Functional Electrical Stimulation in Denervated Musculus Cricoarythenoideus Dorsalis.

    Science.gov (United States)

    Reichel, Martin; Martinek, Johannes

    2014-09-23

    Distribution of the electrical field is very important to activate muscle and nerve cells properly. One therapeutic method to treat Recurrent Laryngeal Neuropathy (RLN) in horses can be performed by Functional Electrical Stimulation (FES). Current method to optimize the stimulation effect is to use implanted quadripolar electrodes to the musculus cricoarythenoideus dorsalis (CAD) and testing electrode configuration until best possible optimum is reached. For better understanding and finding of maximum possible activation of CAD a simulation model of the actual entire setting is currently in development. Therefore the geometric model is built from CT-data of a dissected larynx containing the quadripolar electrodes as well as fiducials for later data registration. The geometric model is the basis for a finite difference method containing of voxels with corresponding electrical conductivity of the different types of tissue due to threshold segmentation of the CT-data. Model validation can be done by the measurement of the 3D electrical potential distribution of a larynx positioned in an electrolytic tray. Finally, measured and calculated results have to be compared as well as further investigated. Preliminary results show, that changes of electrode as well as conductivity configuration leads to significant different voltage distributions and can be well presented by equipotential lines superimposed CT-slices - a Matlab graphical user interface visualizes the results in freely selectable slices of the 3D geometry. Voltage distribution along theoretically estimated fiber paths could be calculated as well as visualized. For further calculation of nerve or denervated muscle fiber activation and its optimization, real fiber paths have to be defined and referenced to the potential- and the CT-data.

  7. The impact of calcium current reversal on neurotransmitter release in the electrically stimulated retina

    Science.gov (United States)

    Werginz, Paul; Rattay, Frank

    2016-08-01

    Objective. In spite of intense theoretical and experimental investigations on electrical nerve stimulation, the influence of reversed ion currents on network activity during extracellular stimulation has not been investigated so far. Approach. Here, the impact of calcium current reversal on neurotransmitter release during subretinal stimulation was analyzed with a computational multi-compartment model of a retinal bipolar cell (BC) that was coupled with a four-pool model for the exocytosis from its ribbon synapses. Emphasis was laid on calcium channel dynamics and how these channels influence synaptic release. Main results. Stronger stimulation with anodic pulses caused transmembrane voltages above the Nernst potential of calcium in the terminals and, by this means, forced calcium ions to flow in the reversed direction from inside to the outside of the cell. Consequently, intracellular calcium concentration decreased resulting in a reduced vesicle release or preventing release at all. This mechanism is expected to lead to a pronounced ring-shaped pattern of exocytosis within a group of neighbored BCs when the stronger stimulated cells close to the electrode fail in releasing vesicles. Significance. Stronger subretinal stimulation causes failure of synaptic exocytosis due to reversal of calcium flow into the extracellular space in cells close to the electrode.

  8. Hardware System for Real-Time EMG Signal Acquisition and Separation Processing during Electrical Stimulation.

    Science.gov (United States)

    Hsueh, Ya-Hsin; Yin, Chieh; Chen, Yan-Hong

    2015-09-01

    The study aimed to develop a real-time electromyography (EMG) signal acquiring and processing device that can acquire signal during electrical stimulation. Since electrical stimulation output can affect EMG signal acquisition, to integrate the two elements into one system, EMG signal transmitting and processing method has to be modified. The whole system was designed in a user-friendly and flexible manner. For EMG signal processing, the system applied Altera Field Programmable Gate Array (FPGA) as the core to instantly process real-time hybrid EMG signal and output the isolated signal in a highly efficient way. The system used the power spectral density to evaluate the accuracy of signal processing, and the cross correlation showed that the delay of real-time processing was only 250 μs.

  9. Local electric stimulation causes conducted calcium response in rat interlobular arteries

    DEFF Research Database (Denmark)

    Salomonsson, Max; Gustafsson, Finn; Andreasen, Ditte

    2002-01-01

    The purpose of the present study was to investigate the conducted Ca(2+) response to local electrical stimulation in isolated rat interlobular arteries. Interlobular arteries were isolated from young Sprague-Dawley rats, loaded with fura 2, and attached to pipettes in a chamber on an inverted...... microscope. Local electrical pulse stimulation (200 ms, 100 V) was administered by means of an NaCl-filled microelectrode (0.7-1 M(Omega)) juxtaposed to one end of the vessel. Intracellular Ca(2+) concentration ([Ca(2+)](i)) was measured with an image system at a site approximately 500 microm from......% of baseline, whereas the response was absent when the electrode was negative. This response was not dependent on perivascular nerves, because the conducted response was unaffected by TTX (1 microM). The conducted [Ca(2+)](i) response was abolished by an ambient Ca(2+) free solution and blunted by nifedipine...

  10. Portable EMG devices, Biofeedback and Contingent Electrical Stimulation applications in Bruxism

    DEFF Research Database (Denmark)

    Castrillon, Eduardo

    Portable EMG devices, Biofeedback and Contingent Electrical Stimulation applications in Bruxism Eduardo Enrique, Castrillon Watanabe, DDS, MSc, PhD Section of Orofacial Pain and Jaw Function, Department of Dentistry, Aarhus University, Aarhus, Denmark; Scandinavian Center for Orofacial Neuroscience...... Summary: Bruxism is a parafunctional activity, which involves the masticatory muscles and probably it is as old as human mankind. Different methods such as portable EMG devices have been proposed to diagnose and understand the pathophysiology of bruxism. Biofeedback / contingent electrical stimulation...... (CES) methods have been also studied lately in the field of bruxism as a management method. Results from studies on portable EMG devices that can assess EMG activity on multiple nights, tell us that it is possible to improve the accuracy of the clinical diagnosis of sleep bruxism. New algorithms...

  11. Radial Basis Function Neural Network-based PID model for functional electrical stimulation system control.

    Science.gov (United States)

    Cheng, Longlong; Zhang, Guangju; Wan, Baikun; Hao, Linlin; Qi, Hongzhi; Ming, Dong

    2009-01-01

    Functional electrical stimulation (FES) has been widely used in the area of neural engineering. It utilizes electrical current to activate nerves innervating extremities affected by paralysis. An effective combination of a traditional PID controller and a neural network, being capable of nonlinear expression and adaptive learning property, supply a more reliable approach to construct FES controller that help the paraplegia complete the action they want. A FES system tuned by Radial Basis Function (RBF) Neural Network-based Proportional-Integral-Derivative (PID) model was designed to control the knee joint according to the desired trajectory through stimulation of lower limbs muscles in this paper. Experiment result shows that the FES system with RBF Neural Network-based PID model get a better performance when tracking the preset trajectory of knee angle comparing with the system adjusted by Ziegler- Nichols tuning PID model.

  12. Focal electrical stimulation of major ganglion cell types in the primate retina for the design of visual prostheses.

    Science.gov (United States)

    Jepson, Lauren H; Hottowy, Pawel; Mathieson, Keith; Gunning, Deborah E; Dabrowski, Wladyslaw; Litke, Alan M; Chichilnisky, E J

    2013-04-24

    Electrical stimulation of retinal neurons with an advanced retinal prosthesis may eventually provide high-resolution artificial vision to the blind. However, the success of future prostheses depends on the ability to activate the major parallel visual pathways of the human visual system. Electrical stimulation of the five numerically dominant retinal ganglion cell types was investigated by simultaneous stimulation and recording in isolated peripheral primate (Macaca sp.) retina using multi-electrode arrays. ON and OFF midget, ON and OFF parasol, and small bistratified ganglion cells could all be activated directly to fire a single spike with submillisecond latency using brief pulses of current within established safety limits. Thresholds for electrical stimulation were similar in all five cell types. In many cases, a single cell could be specifically activated without activating neighboring cells of the same type or other types. These findings support the feasibility of direct electrical stimulation of the major visual pathways at or near their native spatial and temporal resolution.

  13. The effect of electrical stimulation of the corticospinal tract on motor units of the human biceps brachii

    DEFF Research Database (Denmark)

    Petersen, Nicolas Caesar; Taylor, Janet L; Gandevia, Simon C

    2002-01-01

    constructed for 15 single motor units following electrical stimulation of the corticospinal tract and for 11 units following electrical stimulation of large diameter afferents at the brachial plexus. Responses were assessed during weak voluntary contraction. Both types of stimulation produced a single peak...... at short latency in the PSTH (mean 8.5 and 8.7 ms, respectively) and of short duration (responses to electrical stimulation of the corticospinal tract in the relaxed muscle with that in the contracting muscle. The latency was the same......In healthy human subjects, descending motor pathways including the corticospinal tract were stimulated electrically at the level of the cervicomedullary junction to determine the effects on the discharge of motoneurones innervating the biceps brachii. Post-stimulus time histograms (PSTHs) were...

  14. Effectiveness of neuromuscular electrical stimulation in the functional knee rehabilitation in soldiers

    OpenAIRE

    R. Castillo-Lozano

    2015-01-01

    Background: The versatility of military physical therapist practice enables them not only to diagnose knee injuries but also to provide a wide range of definitive care and rehabilitation, reducing the need for costly evacuation. The aim this study was to evaluate the effectiveness of interventions by Neuromuscular Electrical Stimulation (NMES) in the functional knee rehabilitation in soldiers and describe the main predictors and determinants in each intervention. Methods: A systematic search ...

  15. Controlling Your Impulses: Electrical Stimulation of the Human Supplementary Motor Complex Prevents Impulsive Errors

    OpenAIRE

    Spieser, L.; Van den Wildenberg, W; Hasbroucq, T.; Ridderinkhof, K.R.; Burle, B.

    2015-01-01

    International audience; To err is human. However, an inappropriate urge does not always result in error. Impulsive errors thus entail both a motor system capture by an urge to act and a failed inhibition of that impulse. Here we show that neuromodulatory electrical stimulation of the supplementary motor complex in healthy humans leaves action urges unchanged but prevents them from turning into overt errors. Subjects performed a choice reaction-time task known to trigger impulsive responses, l...

  16. Decreased central fatigue in multiple sclerosis patients after 8 weeks of surface functional electrical stimulation

    OpenAIRE

    Ya-Ju Chang, PhD; Miao-Ju Hsu, PhD; Shin-Man Chen, MS; Cheng-Hsiang Lin, PhD; Alice M. K. Wong, MD

    2011-01-01

    Effective treatments for multiple sclerosis (MS)-associated central fatigue have not been established. Surface functional electrical stimulation (FES), which can challenge the peripheral neuromuscular system without overloading the central nervous system, is a relatively safe therapeutic strategy. We investigated the effect of 8 weeks of surface FES training on the levels of general, central, and peripheral fatigue in MS patients. Seven of nine individuals with MS (average age: 42.86 +/– 13.4...

  17. Effects of transcutaneous electrical nerve stimulation and cryotherapy on pain threshold by induced pressure

    OpenAIRE

    Maciel,Lairton Fabricio de Menezes; Ferreira,Jose Jamacy de Almeida; Santos, Heleodorio Honorato dos; Andrade,Palloma Rodrigues de

    2014-01-01

    Studies have shown that cryotherapy, transcutaneous electrical nerve stimulation (TENS) and the association of them promotes analgesia, but the effectiveness of this association is unclear. The objective was to evaluate the effects of single and combined application of TENS and cryotherapy on pressure-induced pain threshold in healthy subjects. The sample consisted of 40 subjects, randomly assigned into four groups: (1) cryotherapy group - CG, (2) TENS group - GT; (3) cryotherapy + TENS group...

  18. Surface neuromuscular electrical stimulation for quadriceps strengthening pre and post total knee replacement.

    LENUS (Irish Health Repository)

    Monaghan, Brenda

    2010-01-01

    Total knee replacement has been demonstrated to be one of the most successful procedures in the treatment of osteoarthritis. However quadriceps weakness and reductions in function are commonly reported following surgery. Recently Neuromuscular Electrical Stimulation (NMES) has been used as an adjunct to traditional strengthening programmes. This review considers the effectiveness of NMES as a means of increasing quadriceps strength in patients before and after total knee replacement.

  19. Neuromuscular Electrical Stimulation and Strength Recovery of Postnatal Diastasis Recti Abdominis Muscles

    OpenAIRE

    Kamel, Dalia M.; Yousif, Amel M.

    2017-01-01

    Objective To assess the effect of neuromuscular electrical stimulation (NMES) on the recovery of abdominal muscle strength in postnatal women with diastasis of recti abdominis muscles (DRAM). Methods Sixty women, 2 months postnatal, participated in this study. They were divided randomly into two equal groups. Group A received NMES in addition to abdominal exercises; group B received only abdominal exercises. The intervention in both groups was for three times per week for 8 weeks. The outcome...

  20. Treatment of Idiopathic Chronic Orchialgia with Transcutaneous Electrical Nerve Stimulation (TENS):A Preliminary Result

    OpenAIRE

    Ekrem Akdeniz; Mustafa Suat Bolat; Sevda Akdeniz

    2016-01-01

    Purpose: Unilateral or bilateral testicular pain lasting more than 3 months is called as chronic orchialgia. Aproximately 25-50% of chronic orchialgia is idiopatic origin. This study aimed the effectiveness of Transcutaneous Electrical Nerve Stimulation (TENS) therapy due to Idiopathic Chronic Orchialgia (ICO). Methods: Five patients were included into this study with ICO that diagnosed with physical examination, urine analyses, urinary system x-ray film, and scrotal doppler ultrasound. Me...

  1. A point process framework for modeling electrical stimulation of the auditory nerve

    Science.gov (United States)

    Rubinstein, Jay T.; Shea-Brown, Eric

    2012-01-01

    Model-based studies of responses of auditory nerve fibers to electrical stimulation can provide insight into the functioning of cochlear implants. Ideally, these studies can identify limitations in sound processing strategies and lead to improved methods for providing sound information to cochlear implant users. To accomplish this, models must accurately describe spiking activity while avoiding excessive complexity that would preclude large-scale simulations of populations of auditory nerve fibers and obscure insight into the mechanisms that influence neural encoding of sound information. In this spirit, we develop a point process model of individual auditory nerve fibers that provides a compact and accurate description of neural responses to electric stimulation. Inspired by the framework of generalized linear models, the proposed model consists of a cascade of linear and nonlinear stages. We show how each of these stages can be associated with biophysical mechanisms and related to models of neuronal dynamics. Moreover, we derive a semianalytical procedure that uniquely determines each parameter in the model on the basis of fundamental statistics from recordings of single fiber responses to electric stimulation, including threshold, relative spread, jitter, and chronaxie. The model also accounts for refractory and summation effects that influence the responses of auditory nerve fibers to high pulse rate stimulation. Throughout, we compare model predictions to published physiological data of response to high and low pulse rate stimulation. We find that the model, although constructed to fit data from single and paired pulse experiments, can accurately predict responses to unmodulated and modulated pulse train stimuli. We close by performing an ideal observer analysis of simulated spike trains in response to sinusoidally amplitude modulated stimuli and find that carrier pulse rate does not affect modulation detection thresholds. PMID:22673331

  2. Electric field depth–focality tradeoff in transcranial magnetic stimulation: simulation comparison of 50 coil designs

    Science.gov (United States)

    Deng, Zhi-De; Lisanby, Sarah H.; Peterchev, Angel V.

    2012-01-01

    Background Various transcranial magnetic stimulation (TMS) coil designs are available or have been proposed. However, key coil characteristics such as electric field focality and attenuation in depth have not been adequately compared. Knowledge of the coil focality and depth characteristics can help TMS researchers and clinicians with coil selection and interpretation of TMS studies. Objective To quantify the electric field focality and depth of penetration of various TMS coils. Methods The electric field distributions induced by 50 TMS coils were simulated in a spherical human head model using the finite element method. For each coil design, we quantified the electric field penetration by the half-value depth, d1/2, and focality by the tangential spread, S1/2, defined as the half-value volume (V1/2) divided by the half-value depth, S1/2 = V1/2/d1/2. Results The 50 TMS coils exhibit a wide range of electric field focality and depth, but all followed a depth–focality tradeoff: coils with larger half-value depth cannot be as focal as more superficial coils. The ranges of achievable d1/2 are similar between coils producing circular and figure-8 electric field patterns, ranging 1.0–3.5 cm and 0.9–3.4 cm, respectively. However, figure-8 field coils are more focal, having S1/2 as low as 5 cm2 compared to 34 cm2 for circular field coils. Conclusions For any coil design, the ability to directly stimulate deeper brain structures is obtained at the expense of inducing wider electrical field spread. Novel coil designs should be benchmarked against comparison coils with consistent metrics such as d1/2 and S1/2. PMID:22483681

  3. Functional Electrical Stimulation in Spinal Cord Injury: Clinical Evidence Versus Daily Practice.

    Science.gov (United States)

    Bersch, Ines; Tesini, Stefani; Bersch, Ulf; Frotzler, Angela

    2015-10-01

    Functional electrical stimulation (FES) has clinical evidence in the rehabilitation of patients with spinal cord injury as indicated by several studies. Both inpatients and outpatients benefit from the therapeutic effect of the FES. The application areas are multifaceted and can be customized on the need for patients. This is represented by the individuality of the programmability of the stimulators and the variety of stimulation schedules that are based on the knowledge about the effects of FES on structural and functional level. Nevertheless, looking into daily clinical practice, the use of FES is rather poor. Expenditure of time, complexity of technical equipment, and compliance and acceptance of therapists and patients should be taken into account as limiting factors. Copyright © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  4. Effect of transcutaneous electrical muscle stimulation on postoperative muscle mass and protein synthesis

    DEFF Research Database (Denmark)

    Vinge, O; Edvardsen, L; Jensen, F

    1996-01-01

    In an experimental study, 13 patients undergoing major elective abdominal surgery were given postoperative transcutaneous electrical muscle stimulation (TEMS) to the quadriceps femoris muscle on one leg; the opposite leg served as control. Changes in cross-sectional area (CSA) and muscle protein...... synthesis were assessed by computed tomography and ribosome analysis of percutaneous muscle biopsies before surgery and on the sixth postoperative day. The percentage of polyribosomes in the ribosome suspension decreased significantly (P stimulated legs (P...... > 0.16). The total concentration of ribosomes decreased significantly in legs treated with TEMS (P 0.16). CSA decreased significantly in both legs. The decrease in polyribosomes and CSA after operation was significantly less in stimulated legs than in controls (P...

  5. An Effective Method on Applying Feedback Error Learning Scheme to Functional Electrical Stimulation Controller

    Science.gov (United States)

    Watanabe, Takashi; Kurosawa, Kenji; Yoshizawa, Makoto

    A Feedback Error Learning (FEL) scheme was found to be applicable to joint angle control by Functional Electrical Stimulation (FES) in our previous study. However, the FEL-FES controller had a problem in learning of the inverse dynamics model (IDM) in some cases. In this paper, methods of applying the FEL to FES control were examined in controlling 1-DOF movement of the wrist joint stimulating 2 muscles through computer simulation under several control conditions with several subject models. The problems in applying FEL to FES controller were suggested to be in restricting stimulation intensity to positive values between the minimum and the maximum intensities and in the case of very small output values of the IDM. Learning of the IDM was greatly improved by considering the IDM output range with setting the minimum ANN output value in calculating ANN connection weight change.

  6. [Effect of stimulating pulse width on the threshold of electrically evoked compound action potential].

    Science.gov (United States)

    Yu, Zhongde; Xiao, Ling; Li, Ping; Meng, Li; Zi, Rui; Fei, Xingbo

    2014-12-01

    This paper discusses the relationship between stimulating pulse width and the threshold of electrically evoked compound action potential (ECAP). Firstly, the rheobase and chronaxy from strength-duration curve of nerve fiber was computed using the shepherd's experiment results. Secondly, based on the relationship between ECAP and the action potential of nerve fiber, a mathematical expression to describe the relationship between stimulating pulse width and ECAP threshold was proposed. Thirdly, the parameters were obtained and the feasibility was proved to the expression with the results of experiment using guinea pigs. Research result showed that with ECAP compared to the action potential of nerve fiber, their threshold function relationship with stimulating pulse width was similar, and rheobase from the former was an order smaller in the magnitude than the latter, but the chronaxy was close to each other. These findings may provide meaningful guidance to clinical ECAP measurement and studying speech processing strategies of cochlear implant.

  7. A microcontroller system for investigating the catch effect: functional electrical stimulation of the common peroneal nerve.

    Science.gov (United States)

    Hart, D J; Taylor, P N; Chappell, P H; Wood, D E

    2006-06-01

    Correction of drop foot in hemiplegic gait is achieved by electrical stimulation of the common peroneal nerve with a series of pulses at a fixed frequency. However, during normal gait, the electromyographic signals from the tibialis anterior muscle indicate that muscle force is not constant but varies during the swing phase. The application of double pulses for the correction of drop foot may enhance the gait by generating greater torque at the ankle and thereby increase the efficiency of the stimulation with reduced fatigue. A flexible controller has been designed around the Odstock Drop Foot Stimulator to deliver different profiles of pulses implementing doublets and optimum series. A peripheral interface controller (PIC) microcontroller with some external circuits has been designed and tested to accommodate six profiles. Preliminary results of the measurements from a normal subject seated in a multi-moment chair (an isometric torque measurement device) indicate that profiles containing doublets and optimum spaced pulses look favourable for clinical use.

  8. Activations of deep lumbar stabilizing muscles by transcutaneous neuromuscular electrical stimulation of lumbar paraspinal regions.

    Science.gov (United States)

    Baek, Seung Ok; Ahn, Sang Ho; Jones, Rodney; Cho, Hee Kyung; Jung, Gil Su; Cho, Yun Woo; Tak, Hyeong Jun

    2014-08-01

    To investigate changes in lumbar multifidus (LM) and deep lumbar stabilizing abdominal muscles (transverse abdominis [TrA] and obliquus internus [OI]) during transcutaneous neuromuscular electrical stimulation (NMES) of lumbar paraspinal L4-L5 regions using real-time ultrasound imaging (RUSI). Lumbar paraspinal regions of 20 healthy physically active male volunteers were stimulated at 20, 50, and 80 Hz. Ultrasound images of the LM, TrA, OI, and obliquus externus (OE) were captured during stimulation at each frequency. The thicknesses of superficial LM and deep LM as measured by RUSI were greater during NMES than at rest for all three frequencies (pRUSI. The findings of this study suggested that transcutaneous NMES might be useful for improving spinal stability and strength in patients having difficulty initiating contraction of these muscles.

  9. [ELECTRIC STIMULATION OF VAGUS NERVE MODULATES A PROPAGATION OF OXYGEN EPILEPSY IN RABBITS].

    Science.gov (United States)

    Zhilyaev, S Yu; Moskvin, A N; Platonova, T F; Demchenko, I T

    2015-11-01

    The activation of autonomic afferents (achieved through the vagus nerve (VN) electrical stimulation) on CNS O2 toxicity and cardiovascular function was investigated. In conscious rabbits at 5 ATA 02, prodromal signs of CNS O2 toxicity and convulsion latency were determined with and without vagus nerve (VN) stimulation. EEG, ECG and respiration were also recorded. In rabbits at 5 ATA, sympathetic overdrive and specific patterns on the EEG (synchronization of slow-waves), ECG (tachycardia) and respiration (respiratory minute volume increase) preceded motor convulsions. Vagus nerve stimulation increased parasympathetic component of autonomic drive and significantly delayed prodromal signs of oxygen toxicity and convulsion latency. Autonomic afferent input to the brain is a novel target for preventing CNS toxicity in HBO2.

  10. Comparing joint kinematics and center of mass acceleration as feedback for control of standing balance by functional neuromuscular stimulation

    Directory of Open Access Journals (Sweden)

    Nataraj Raviraj

    2012-05-01

    Full Text Available Abstract Background The purpose of this study was to determine the comparative effectiveness of feedback control systems for maintaining standing balance based on joint kinematics or total body center of mass (COM acceleration, and assess their clinical practicality for standing neuroprostheses after spinal cord injury (SCI. Methods In simulation, controller performance was measured according to the upper extremity effort required to stabilize a three-dimensional model of bipedal standing against a variety of postural disturbances. Three cases were investigated: proportional-derivative control based on joint kinematics alone, COM acceleration feedback alone, and combined joint kinematics and COM acceleration feedback. Additionally, pilot data was collected during external perturbations of an individual with SCI standing with functional neuromuscular stimulation (FNS, and the resulting joint kinematics and COM acceleration data was analyzed. Results Compared to the baseline case of maximal constant muscle excitations, the three control systems reduced the mean upper extremity loading by 51%, 43% and 56%, respectively against external force-pulse perturbations. Controller robustness was defined as the degradation in performance with increasing levels of input errors expected with clinical deployment of sensor-based feedback. At error levels typical for body-mounted inertial sensors, performance degradation due to sensor noise and placement were negligible. However, at typical tracking error levels, performance could degrade as much as 86% for joint kinematics feedback and 35% for COM acceleration feedback. Pilot data indicated that COM acceleration could be estimated with a few well-placed sensors and efficiently captures information related to movement synergies observed during perturbed bipedal standing following SCI. Conclusions Overall, COM acceleration feedback may be a more feasible solution for control of standing with FNS given its

  11. Is transcutaneous electrical stimulation a realistic surrogate for genuine surgical stimulation during spinal anesthesia for cesarean delivery?

    Science.gov (United States)

    Zaidi, Asif S H; Russell, Ian F

    2005-05-01

    Several studies have investigated differential block during spinal anesthesia using transcutaneous electrical stimulation (TES) applied to patient's skin. These TES stimuli are claimed to be a surrogate for surgical stimulation, but TES has never been shown to be a realistic surrogate for a surgical stimulus during regional anesthesia. We investigated whether patients could appreciate nonpainful TES at the same time as they were undergoing painless cesarean delivery surgery. We applied a nonpainful TES (10 mA, 50 Hz, 1-s duration) to the skin, at 5 different dermatomal levels, in 20 women undergoing elective cesarean delivery during spinal anesthesia. During surgery, all the women were totally pain free but we noted that the level of block to TES was variable: in 30% of women, TES could be felt at the T10 dermatome or more caudally. The first appreciation of touch was consistently at T6 or above. The fact that a nonpainful TES stimulus could be appreciated within the dermatomes directly involved in transmitting surgical stimuli, at a time when the patients were totally pain free, suggests that TES at the tested levels is of little value as a surrogate surgical stimulus.

  12. Effects of involuntary eccentric contraction training by neuromuscular electrical stimulation on the enhancement of muscle strength.

    Science.gov (United States)

    Son, Jongsang; Lee, Dongyeop; Kim, Youngho

    2014-08-01

    Neuromuscular electrical stimulation is well-known as a modality to improve the performance of neuromuscular system, but its clinical value on muscle strengthening remains equivocal. In this study, we designed a system for an involuntary eccentric contraction of biceps brachii muscles using continuous passive movement and commercial neuromuscular electrical stimulation devices. To investigate the effects of involuntary eccentric contraction training by neuromuscular electrical stimulation on the enhancement of muscle strength, seven healthy men between the ages of 24 and 29 years participated in this study. Participants were trained two times per week for 12 weeks. Each exercise session was performed for 30 min with no rest intervals. Isometric elbow flexion torque and biceps brachii muscle thickness were chosen as evaluation indices, and were measured at pre-/post-training. After the 12-week training, the isometric elbow flexion torque of the trained side significantly increased by approximately 23% compared to the initial performance (P<0.01). Meanwhile, the torque of the untrained side showed no significant change (P=0.862). During the 12-week training period, the biceps brachii muscle thickness of the trained side significantly increased by around 8% at rest and 16% at maximum voluntary contraction (P<0.01). The developed system and the technique show promising results, suggesting that it has the potential to be used to increase the muscle strength in patients with neuromuscular disease and to be implemented in design rehabilitative protocols. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Training and orthotic effects related to functional electrical stimulation of the peroneal nerve in stroke.

    Science.gov (United States)

    Street, Tamsyn; Swain, Ian; Taylor, Paul

    2017-01-31

    To examine the evidence for a training effect on the lower limb of functional electrical stimulation. Cohort study. A total of 133 patients >6 months post-stroke. Training and orthotic effects were determined from walking speed over 10 m, associated minimal and substantial clinically important differences (i.e. >0.05 and >0.10 m/s), and Functional Ambulation Category (FAC), ranging from household walking to independent walking in the community. An overall significant (p training effect was found that was not a clinically important difference (0.02 m/s); however, "community" FAC (≥ 0.8 m/s) and "most limited community walkers" FAC (0.4-0.58 m/s), but not "household walkers" (training effect, compared with 43% due to an orthotic effect. The findings suggest that functional electrical stimulation provides a training effect in those who are less impaired. Further work, which optimizes the use of the device for restoration of function, rather than as an orthotic device, will provide greater clarity on the effectiveness of functional electrical stimulation for eliciting a training effect.

  14. Exercise adherence during home-based functional electrical stimulation cycling by individuals with spinal cord injury.

    Science.gov (United States)

    Dolbow, David R; Gorgey, Ashraf S; Ketchum, Jessica M; Moore, Jewel R; Hackett, Laurel A; Gater, David R

    2012-11-01

    The typically sedentary spinal cord injured population has limited physical activity options because of muscle paralysis, difficulties in transportation, and barriers to access rehabilitation/wellness facilities. It is important to investigate physical activity alternatives to increase physical activity levels and decrease the risk of inactivity-derived diseases. The goal of this study was to determine the effects of a home-based functional electrical stimulation cycling program on exercise adherence of those with spinal cord injury. Seventeen Veterans with posttraumatic C4-T11 American Spinal Injury Association Impairment Scale A-C spinal cord injury participated in two 8-wk exercise periods of home-based functional electrical stimulation lower extremity cycling. Exercise adherence and the effects of six factors thought to influence exercise adherence were studied during both exercise periods. Exercise adherence rates for exercise periods 1 and 2 were 71.7% and 62.9%, respectively. Age, history of exercise, and pain not associated with the exercise activity were determined to have significant impact on exercise adherence rates. Exercise adherence rates were well above the reported 35% in the able-bodied population, which provides evidence for the feasibility of a home-based functional electrical stimulation lower extremity cycling program. Younger adults with a history of being physically active have the highest potential for exercise adherence.

  15. [The influence of electrical stimulation on the peripheral immune system under the experimental and clinical conditions].

    Science.gov (United States)

    Lazarenko, N N; Supova, M V; Trunova, O V; Smirnova, S N; Prikuls, V F

    2015-01-01

    The authors for the first time provide the scientifically-grounded substantiation for the application of electrical stimulation with bipolar pulsed currents for the combined treatment of the patents presenting with acne vulgaris. Experiments on the rabbits have demonstrated the influence of bipolar pulsed currents on the cellular composition of lymph nodes and thereby facilitated the better understanding of certain theoretical aspects of the application of electrical stimulation at large. The clinical study on the application of multi-channel electrical stimulation and microcurrent therapy showed that these physical factors may cause remodeling of immunogenesis in the patents presenting with acne vulgaris manifested as the normalization of the cellular composition of peripheral blood (leukocyte, lymphocyte, T- and B-lymphocyte counts and immunoglobulin levels). These findings confirm the effectiveness of the proposed integrated treatment responsible for the enhancement of the overall resistance of the patents with acne vulgaris. Moreover, this therapeutic modality proved to exert the immunocorrective action and promote the restoration of the adaptive capacity at large. As a result, 80.9% of the patients presenting with acne vulgaris enjoyed prolonged remission of the disease.

  16. Rebuilding motor function of the spinal cord based on functional electrical stimulation.

    Science.gov (United States)

    Shen, Xiao-Yan; Du, Wei; Huang, Wei; Chen, Yi

    2016-08-01

    Rebuilding the damaged motor function caused by spinal cord injury is one of the most serious challenges in clinical neuroscience. The function of the neural pathway under the damaged sites can be rebuilt using functional electrical stimulation technology. In this study, the locations of motor function sites in the lumbosacral spinal cord were determined with functional electrical stimulation technology. A three-dimensional map of the lumbosacral spinal cord comprising the relationship between the motor function sites and the corresponding muscle was drawn. Based on the individual experimental parameters and normalized coordinates of the motor function sites, the motor function sites that control a certain muscle were calculated. Phasing pulse sequences were delivered to the determined motor function sites in the spinal cord and hip extension, hip flexion, ankle plantarflexion, and ankle dorsiflexion movements were successfully achieved. The results show that the map of the spinal cord motor function sites was valid. This map can provide guidance for the selection of electrical stimulation sites during the rebuilding of motor function after spinal cord injury.

  17. Near-infrared signals associated with electrical stimulation of peripheral nerves

    Science.gov (United States)

    Fantini, Sergio; Chen, Debbie K.; Martin, Jeffrey M.; Sassaroli, Angelo; Bergethon, Peter R.

    2009-02-01

    We report our studies on the optical signals measured non-invasively on electrically stimulated peripheral nerves. The stimulation consists of the delivery of 0.1 ms current pulses, below the threshold for triggering any visible motion, to a peripheral nerve in human subjects (we have studied the sural nerve and the median nerve). In response to electrical stimulation, we observe an optical signal that peaks at about 100 ms post-stimulus, on a much longer time scale than the few milliseconds duration of the electrical response, or sensory nerve action potential (SNAP). While the 100 ms optical signal we measured is not a direct optical signature of neural activation, it is nevertheless indicative of a mediated response to neural activation. We argue that this may provide information useful for understanding the origin of the fast optical signal (also on a 100 ms time scale) that has been measured non-invasively in the brain in response to cerebral activation. Furthermore, the optical response to peripheral nerve activation may be developed into a diagnostic tool for peripheral neuropathies, as suggested by the delayed optical signals (average peak time: 230 ms) measured in patients with diabetic neuropathy with respect to normal subjects (average peak time: 160 ms).

  18. Influence of electrical stimulation frequency on skeletal muscle force and fatigue.

    Science.gov (United States)

    Dreibati, B; Lavet, C; Pinti, A; Poumarat, G

    2010-05-01

    The aim of this study is to determine the impact of electrical stimulation frequency on muscle force and fatigue and propose application modalities in regards to sports or clinical rehabilitation training. The maximal voluntary contraction (MVC) force of the quadriceps femoris muscle was recorded before, during and after electrical stimulation in 26 healthy adults during 20-minute sessions corresponding to 60 of 5-second contractions separated by 15-second rest periods. Three different frequencies were used: 100, 50 and 20 Hz. With a frequency of 100 Hz, we obtained 71% of the MVC force at the beginning of the session (MVCb). The decrease in muscle force at the end of the session is significantly greater for the highest frequencies respectively 27, 33 and 38% of MVCb for 100, 50 and 20 Hz. The impact of electrical stimulation to improve muscle force seems to be dependent on frequency, intensity pulse trains and number of contractions per session. Higher intensity and higher frequency induce stronger muscular contractions, but also a stronger decline in force and thus quick-setting muscle fatigue. Classical 20-minute training sessions with many contractions (60 or more) do not seem appropriate for sports training or clinical rehabilitation programs. Copyright 2010 Elsevier Masson SAS. All rights reserved.

  19. Evaluation of the effectiveness of neuromuscular electrical stimulation after total knee arthroplasty: a meta-analysis.

    Science.gov (United States)

    Bistolfi, Alessandro; Zanovello, Jessica; Ferracini, Riccardo; Allisiardi, Fabrizio; Lioce, Elisa; Magistroni, Ernesta; Berchialla, Paola; Da Rold, Ilaria; Massazza, Giuseppe

    2017-10-07

    to evaluate the efficacy of the use of the neuromuscular electrical stimulation (NMES) after total knee arthroplasty (TKA). a systematic review of randomized controlled trials (MEDLINE, PubMed, Cochrane Library, and PEDro) using PICOS approach to formulate the research question, Controlled terms and Boolean operators. Inclusion and exclusion criteria were defined in advance. "Neuromuscular electrical stimulation" and "total knee arthroplasty" were used as keywords. The overall risk of bias was determined according to: random sequence generation, concealment, blinding mass of participants and staff, commissioning blind assessment results, incomplete data and loans received. out of the 36 identified studies, six were included in the review (496 participants). In these studies, one group of patients followed a rehabilitation protocol (control-group) and the other followed a rehabilitation program plus a session of neuromuscular electrical stimulation (NMES-group). Patients of NMES-groups got the best scores (Timed Up and Go Test, Stair-Climbing Test and Walk Test). NMES benefits were strong in the first postoperative weeks/months and gradually diminished. NMES allows a slightly better functional recovery following TKA, especially in the first period, with more evident benefits in patients with a severe lack of muscular activation. Nevertheless, there is no difference at medium-long term.

  20. Restoration of gait and motor recovery by functional electrical stimulation therapy in persons with stroke.

    Science.gov (United States)

    Sabut, Sukanta K; Sikdar, Chanda; Mondal, Ramkrishna; Kumar, Ratnesh; Mahadevappa, Manjunatha

    2010-01-01

    To evaluate the clinical efficacy of functional electrical stimulation (FES) therapy of the tibialis anterior (TA) muscle on gait restoration and enhancing motor recovery with stroke patients. Thirty hemiparetic participants with spastic foot-drop impairments who were at least 3 months post-stroke were recruited from a rehabilitation institute and were assigned either to a control group or a FES group. Both the groups participated in a conventional stroke rehabilitation program for 60 min per day, 5 days a week, for 12-weeks. The FES group received the electrical stimulation to the TA muscle for correction of foot-drop. Functional electric stimulation (FES) resulted in a 26.3% (p control group was only 11.5% (p control group in other gait parameters (e.g. cadence, step length), physiological cost index (PCI), ankle range of motion, spasticity of calf muscle, Fugl-Meyer scores, and the maximum value of the root mean square (RMS(max)), which reflects the capacity of the muscle output. These findings suggest that, the FES therapy combined with conventional therapy treatment more effectively improves the walking ability and enhances the motor recovery when compared with conventional therapy alone in stroke survivors.

  1. Artificial motor control for electrically stimulated upper limbs of plegic or paretic people

    Directory of Open Access Journals (Sweden)

    Elgison da Luz dos Santos

    Full Text Available Introduction: Functional Electrical Stimulation (FES is a technique used in the restoration and generation of movements performed by subjects with neuromuscular disorders such as spinal cord injury (SCI. The purpose of this article is to outline the state of the art and perspectives of the use of FES in artificial motor control of the upper limbs in paretic or plegic people. Methods The databases used in papers selection were Google Scholar and Capes’ Portals as well as proceedings of the Annual Conference of the International Functional Electrical Stimulation Society (IFESS. Results Approximately 85% of the reviewed studies showed FES profile with pulse duration ranging from 1 to 300 μs and modulating (burst frequency between 10 and 40 Hz. Regarding the type of electrodes, 88% of the studies employed transcutaneous electrodes. Conclusion We concluded that FES with closed-loop feedback and feedforward are the most used and most viable systems for upper limbs motor control, because they perform self-corrections slowing neuromuscular adaptation, allowing different planes and more range of movement and sensory-motor integration. One of the difficulties found in neuroprosthesis systems are electrical wires attached to the user, becoming uninteresting in relation to aesthetics and break. The future perspectives lead to a trend to miniaturization of the stimulation equipment and the availability of wireless networks, which allow the attachment of modules to other components without physical contact, and will become more attractive for daily use.

  2. Rebuilding motor function of the spinal cord based on functional electrical stimulation

    Directory of Open Access Journals (Sweden)

    Xiao-yan Shen

    2016-01-01

    Full Text Available Rebuilding the damaged motor function caused by spinal cord injury is one of the most serious challenges in clinical neuroscience. The function of the neural pathway under the damaged sites can be rebuilt using functional electrical stimulation technology. In this study, the locations of motor function sites in the lumbosacral spinal cord were determined with functional electrical stimulation technology. A three-dimensional map of the lumbosacral spinal cord comprising the relationship between the motor function sites and the corresponding muscle was drawn. Based on the individual experimental parameters and normalized coordinates of the motor function sites, the motor function sites that control a certain muscle were calculated. Phasing pulse sequences were delivered to the determined motor function sites in the spinal cord and hip extension, hip flexion, ankle plantarflexion, and ankle dorsiflexion movements were successfully achieved. The results show that the map of the spinal cord motor function sites was valid. This map can provide guidance for the selection of electrical stimulation sites during the rebuilding of motor function after spinal cord injury.

  3. Motor Skill Acquisition and Retention after Somatosensory Electrical Stimulation in Healthy Humans

    Directory of Open Access Journals (Sweden)

    Menno Pieter Veldman

    2016-03-01

    Full Text Available Somatosensory electrical stimulation (SES can increase motor performance, presumably through a modulation of neuronal excitability. Because the effects of SES can outlast the period of stimulation, we examined the possibility that SES can also enhance the retention of motor performance, motor memory consolidation, after 24 hours (Day 2 and 7 days (Day 7, that such effects would be scaled by SES duration, and that such effects were mediated by changes in aspects of corticospinal excitability, short-interval intracortical inhibition (SICI, and intracortical facilitation (ICF. Healthy young adults (n = 40 received either 20 (SES-20, 40 (SES-40, or 60 minutes (SES-60 of real SES, or sham SES (SES-0. The results showed SES-20 increased visuomotor performance on Day 2 (15% and Day 7 (17% and SES-60 increased visuomotor performance on Day 7 (11%; all p < 0.05 compared with SES-0. Specific responses to transcranial magnetic stimulation (TMS increased immediately after SES (p < 0.05 but not on Days 2 and 7. In addition, changes in behavioral and neurophysiological parameters did not correlate, suggesting that paths and structures other than the ones TMS can assay must be (also involved in the increases in visuomotor performance after SES. As examined in the present study, low-intensity peripheral electrical nerve stimulation did not have acute effects on healthy adults’ visuomotor performance but SES had delayed effects in the form of enhanced motor memory consolidation that were not scaled by the duration of SES.

  4. Potential interests and limits of magnetic and electrical stimulation techniques to assess neuromuscular fatigue.

    Science.gov (United States)

    Millet, G Y; Bachasson, D; Temesi, J; Wuyam, B; Féasson, L; Vergès, S; Lévy, P

    2012-12-01

    Neuromuscular function can change under different conditions such as ageing, training/detraining, long-term spaceflight, environmental conditions (e.g. hypoxia, hyperthermia), disease, therapy/retraining programs and also with the appearance of fatigue. Neuromuscular fatigue can be defined as any decrease in maximal voluntary strength or power. There is no standardized method to induce fatigue and various protocols involving different contraction patterns (such as sustained or intermittent submaximal isometric or dynamic contractions on isokinetic or custom chairs) have been used. Probably due to lack of motivation/cooperation, results of fatigue resistance protocols are more variable in patients than in healthy subjects. Magnetic and electrical stimulation techniques allow non-invasive assessment of central and peripheral origins of fatigue. They also allow investigation of different types of muscle fatigue when combining various types of stimulation with force/surface EMG measurements. Since maximal electrical stimuli may be uncomfortable or even sometimes painful, several alternative methods have been recently proposed: submaximal muscle stimulation, low/high-frequency paired pulses instead of tetanic stimuli and the use of magnetic stimulation at the peripheral level. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Classical and adaptive control of ex vivo skeletal muscle contractions using Functional Electrical Stimulation (FES.

    Directory of Open Access Journals (Sweden)

    Paola Jaramillo Cienfuegos

    Full Text Available Functional Electrical Stimulation is a promising approach to treat patients by stimulating the peripheral nerves and their corresponding motor neurons using electrical current. This technique helps maintain muscle mass and promote blood flow in the absence of a functioning nervous system. The goal of this work is to control muscle contractions from FES via three different algorithms and assess the most appropriate controller providing effective stimulation of the muscle. An open-loop system and a closed-loop system with three types of model-free feedback controllers were assessed for tracking control of skeletal muscle contractions: a Proportional-Integral (PI controller, a Model Reference Adaptive Control algorithm, and an Adaptive Augmented PI system. Furthermore, a mathematical model of a muscle-mass-spring system was implemented in simulation to test the open-loop case and closed-loop controllers. These simulations were carried out and then validated through experiments ex vivo. The experiments included muscle contractions following four distinct trajectories: a step, sine, ramp, and square wave. Overall, the closed-loop controllers followed the stimulation trajectories set for all the simulated and tested muscles. When comparing the experimental outcomes of each controller, we concluded that the Adaptive Augmented PI algorithm provided the best closed-loop performance for speed of convergence and disturbance rejection.

  6. Excitation of oxytocin cells in the hypothalamic supraoptic nucleus by electrical stimulation of the dorsal penile nerve and tactile stimulation of the penis in the rat.

    Science