WorldWideScience

Sample records for bilateral electrical stimulation

  1. The effects of bilateral electric and bimodal electric--acoustic stimulation on language development.

    Science.gov (United States)

    Nittrouer, Susan; Chapman, Christopher

    2009-09-01

    There is no doubt that cochlear implants have improved the spoken language abilities of children with hearing loss, but delays persist. Consequently, it is imperative that new treatment options be explored. This study evaluated one aspect of treatment that might be modified, that having to do with bilateral implants and bimodal stimulation. A total of 58 children with at least one implant were tested at 42 months of age on four language measures spanning a continuum from basic to generative in nature. When children were grouped by the kind of stimulation they had at 42 months (one implant, bilateral implants, or bimodal stimulation), no differences across groups were observed. This was true even when groups were constrained to only children who had at least 12 months to acclimatize to their stimulation configuration. However, when children were grouped according to whether or not they had spent any time with bimodal stimulation (either consistently since their first implant or as an interlude to receiving a second) advantages were found for children who had some bimodal experience, but those advantages were restricted to language abilities that are generative in nature. Thus, previously reported benefits of simultaneous bilateral implantation early in a child's life may not extend to generative language. In fact, children may benefit from a period of bimodal stimulation early in childhood because low-frequency speech signals provide prosody and serve as an aid in learning how to perceptually organize the signal that is received through a cochlear implant. PMID:19713210

  2. Transcranial Electric Field Stimulation

    OpenAIRE

    Arfaee, Arash

    2015-01-01

    Nervous stimulation with electric methods not only has a long history in the treatment of many conditions but also in the last two decades has been used increasingly as a powerful functional brain mapping tool alongside other imaging techniques. This technology has been used to record the stimulation-evoked activity of the stimulated location. This research describes work surrounding a novel technique for brain and nervous stimulation using the electric field as the medium; particularly tra...

  3. Bilateral compared with unilateral sacral nerve stimulation for faecal incontinence

    DEFF Research Database (Denmark)

    Duelund-Jakobsen, J; Buntzen, S; Lundby, L;

    2015-01-01

    % improvement were eligible. Twenty-seven patients who accepted to enter the trial were bilaterally implanted with two permanent leads and pacemakers. Patients were randomized into three periods of four weeks stimulation including unilateral right, unilateral left and bilateral. Symptoms scores and bowel habit...... incontinence is not superior to standard unilateral stimulation in the short term. Equal functional results can be obtained regardless the side of implantation. This article is protected by copyright. All rights reserved....

  4. Bilateral electric energy contracts: return and risk

    Energy Technology Data Exchange (ETDEWEB)

    Gunn, Laura K.; Silva, Elisa B.; Correia, Paulo B. [State University of Campinas (UNICAMP), SP (Brazil). College of Mechanical Engineering

    2009-07-01

    In Brazil electricity is traded through three segments: the spot market that balances offer and demand, with prices calculated by a cost-based computational model; the regulated market , where prices are settled in public auctions, and the free market for bilateral contracts. As spot and regulated market prices are public information, a seller is able to calculate his opportunity price to trade a bilateral contract in the free market by using the non-arbitrage principle. Thus, the seller searches the price of a bilateral contract in the free market that balances his/her revenues with the value expected in case it were negotiated in the regulated and the spot market. Besides the expected revenue, the seller may also consider the CVaR to measure the risk of her/his bilateral contract in the free market. So this paper develops a binomial lattice approach to price bilateral contracts in the free market, considering the seller's opportunity of negotiations in both regulated and spot markets, and measuring the contract risk directly. (author)

  5. Bilateral adaptive deep brain stimulation is effective in Parkinson's disease

    Science.gov (United States)

    Little, Simon; Beudel, Martijn; Zrinzo, Ludvic; Foltynie, Thomas; Limousin, Patricia; Hariz, Marwan; Neal, Spencer; Cheeran, Binith; Cagnan, Hayriye; Gratwicke, James; Aziz, Tipu Z; Pogosyan, Alex; Brown, Peter

    2016-01-01

    Introduction & objectives Adaptive deep brain stimulation (aDBS) uses feedback from brain signals to guide stimulation. A recent acute trial of unilateral aDBS showed that aDBS can lead to substantial improvements in contralateral hemibody Unified Parkinson’s Disease Rating Scale (UPDRS) motor scores and may be superior to conventional continuous DBS in Parkinson’s disease (PD). We test whether potential benefits are retained with bilateral aDBS and in the face of concurrent medication. Methods We applied bilateral aDBS in 4 patients with PD undergoing DBS of the subthalamic nucleus. aDBS was delivered bilaterally with independent triggering of stimulation according to the amplitude of β activity at the corresponding electrode. Mean stimulation voltage was 3.0±0.1 volts. Motor assessments consisted of double-blinded video-taped motor UPDRS scores that included both limb and axial features. Results UPDRS scores were 43% (p=0.04; Cohen’s d=1.62) better with aDBS than without stimulation. Motor improvement with aDBS occurred despite an average time on stimulation (ToS) of only 45%. Levodopa was well tolerated during aDBS and led to further reductions in ToS. Conclusion Bilateral aDBS can improve both axial and limb symptoms and can track the need for stimulation across drug states. PMID:26424898

  6. Neuropsychological functioning following bilateral subthalamic nucleus stimulation in Parkinson's disease.

    Science.gov (United States)

    Morrison, C E; Borod, J C; Perrine, K; Beric, A; Brin, M F; Rezai, A; Kelly, P; Sterio, D; Germano, I; Weisz, D; Olanow, C W

    2004-03-01

    The cognitive effects of subthalamic nucleus (STN) stimulation in Parkinson's disease (PD) have been examined. However, there are no reported studies that evaluate, by incorporating a disease control group, whether neuropsychological performance in surgical patients changes beyond the variability of the assessment measures. To examine this issue, 17 PD patients were tested before and after bilateral STN stimulator implantation, both on and off stimulation. Eleven matched PD controls were administered the same repeatable neuropsychological test battery twice. Relative to changes seen in the controls, the surgery for electrode placement mildly adversely affected attention and language functions. STN stimulation, per se, had little effect on cognition. The STN DBS procedure as a whole resulted in a mild decline in delayed verbal recall and language functions. There were no surgery, stimulation, or procedure effects on depression scale scores. In contrast to these group findings, one DBS patient demonstrated significant cognitive decline following surgery. PMID:15010083

  7. Refractory headaches treated with bilateral occipital and temporal region stimulation

    OpenAIRE

    Zach KJ; Trentman TL; Zimmerman RS; DW, Dodick

    2014-01-01

    Kelly J Zach,1 Terrence L Trentman,1 Richard S Zimmerman,2 David W Dodick31Department of Anesthesiology, 2Department of Neurosurgery, 3Department of Neurology, Mayo Clinic in Arizona, Phoenix, AZ, USAObjectives: To describe use of bilateral temporal and occipital stimulator leads for a refractory headache disorder.Materials and methods: A 31-year-old female had a 10-year history of chronic, severe occipital and temporal region headaches. The patient underwent permanent implant of an occipital...

  8. 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

  9. 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.

  10. Electrical stimulation of mechanoreceptors

    International Nuclear Information System (INIS)

    Within the field of Rehabilitation Engineering, this work is aimed at identifying the optimal parameters of electric current stimulus which activate the nervous axons of mecanoreceptors found in the fingertip, allowing, this way, to resemble tactile senses. These sensorial feelings can be used by aiding technological means, namely, the sensorial substitution technology, in an attempt to render information to blind people through the tactile sense. The physical pressure on sensorial areas (fingertips) used for reading activities through the Braille System is the main effect that is imitated and studied in this research work. An experimental aiding prototype for Braille reading research has been developed and tested with blinds and reduced vision people, with highly satisfactory results.

  11. Neuromuscular Electrical Stimulation for Skeletal Muscle Function

    OpenAIRE

    Doucet, Barbara M.; Lam, Amy; Griffin, Lisa

    2012-01-01

    Lack of neural innervation due to neurological damage renders muscle unable to produce force. Use of electrical stimulation is a medium in which investigators have tried to find a way to restore movement and the ability to perform activities of daily living. Different methods of applying electrical current to modify neuromuscular activity are electrical stimulation (ES), neuromuscular electrical stimulation (NMES), transcutaneous electrical nerve stimulation (TENS), and functional electrical ...

  12. Bilateral posterior shoulder dislocation after electrical shock: A case report

    OpenAIRE

    Ismail Emre Ketenci; Tahir Mutlu Duymus; Ayhan Ulusoy; Hakan Serhat Yanik; Serhat Mutlu; Mehmet Oguz Durakbasa

    2015-01-01

    Introduction: Posterior dislocation of the shoulder is a rare and commonly missed injury. Unilateral dislocations occur mostly due to trauma. Bilateral posterior shoulder dislocations are even more rare and result mainly from epileptic seizures. Electrical injury is a rare cause of posterior shoulder dislocation. Injury mechanism in electrical injury is similar to epileptic seizures, where the shoulder is forced to internal rotation, flexion and adduction. Presentation of case: This report...

  13. Electrophysiological correlates of bilateral and unilateral repetitive transcranial magnetic stimulation in patients with bipolar depression.

    Science.gov (United States)

    Kazemi, Reza; Rostami, Reza; Khomami, Sanaz; Horacek, Jiri; Brunovsky, Martin; Novak, Tomas; Fitzgerald, Paul B

    2016-06-30

    Repetitive transcranial magnetic stimulation (rTMS) has been demonstrated to have efficacy in the treatment of unipolar depression but limited research has explored the efficacy of rTMS in bipolar depression. Therefore, we conducted a comparative clinical trial evaluating clinical responses to prefrontal bilateral and unilateral rTMS in patients suffering from bipolar depression. We hypothesized that, 1) the response to the treatment would be associated with a decrease in the frequency of beta waves, 2) bilateral stimulation of the cortex would bring about more extensive changes in brain activity than unilateral stimulation, and 3) bilateral stimulation is more effective than unilateral. Thirty patients with bipolar depression were divided into two groups. Bilateral Group (n=15) who received rTMS in the left DLPFC (10Hz) and right DLPFC (1-Hz), and unilateral group (n=15) who received the stimulation only in the right DLPFC (1-Hz) during 20 treatment sessions. The proportion of responders in the bilateral stimulation group was significantly higher than that in the unilateral group [80% versus 47%]. The remission rate was 40% in the bilateral group and 40% in the unilateral group (not significant). In the responders to bilateral rTMS treatment, a significant reduction of alpha1-2, beta 1-3, and gamma frequencies were observed in medial and superior frontal and cingulate gyrus . Responders to the unilateral treatment showed decrease of gamma frequency in postcentral gyrus, precuneus, superior and inferior parietal lobule, Cuneus and angular gyrus. In conclusion, we found that bilateral stimulation was more effective than the unilateral stimulation and evidence that beta frequency activity could possibly be used as a marker for response to rTMS. PMID:27138833

  14. Preventing long-lasting fear recovery using bilateral alternating sensory stimulation: A translational study.

    Science.gov (United States)

    Wurtz, H; El-Khoury-Malhame, M; Wilhelm, F H; Michael, T; Beetz, E M; Roques, J; Reynaud, E; Courtin, J; Khalfa, S; Herry, C

    2016-05-01

    Posttraumatic stress disorder (PTSD) is a highly debilitating and prevalent psychological disorder. It is characterized by highly distressing intrusive trauma memories that are partly explained by fear conditioning. Despite efficient therapeutic approaches, a subset of PTSD patients displays spontaneous recurrence of traumatic memories after successful treatment. The development of animal behavioral models mimicking the individual variability in treatment outcome for PTSD patients represent therefore an important challenge as it allows for the identification of predicting factors of resilience or susceptibility to relapse. However, to date, only few animal behavioral models of long-lasting fear recovery have been developed and their predictive validity has not been tested directly. The objectives of this study were twofold. First we aimed to develop a simple animal behavioral model of long-lasting fear recovery based on auditory cued fear conditioning and extinction learning, which recapitulates the heterogeneity of fear responses observed in PTSD patients after successful treatment. Second we aimed at testing the predictive validity of our behavioral model and used to this purpose a translational approach based (i) on the demonstration of the efficiency of Eye Movement Desensitization and Reprocessing (EMDR) therapy to reduce conditioned fear responses in PTSD patients and (ii) on the implementation in our behavioral model of an electrical bilateral alternating stimulation of the eyelid which mimics the core feature of EMDR. Our data indicate that electrical bilateral alternating stimulation of the eyelid during extinction learning alleviates long-lasting fear recovery of conditioned fear responses and dramatically reduces inter-individual variability. These results demonstrate the face and predictive validity of our animal behavioral model and provide an interesting tool to understand the neurobiological underpinnings of long-lasting fear recovery. PMID:26091614

  15. Braille line using electrical stimulation

    International Nuclear Information System (INIS)

    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

  16. 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.

  17. Electricity market risk management using forward contracts with bilateral options

    International Nuclear Information System (INIS)

    Extreme short-term price volatility in competitive electricity markets creates the need for risk management arrangements. A new electricity forward contract with bilateral financial options is introduced, which allows both seller and buyer to take advantage of flexibility in generation and consumption to obtain monetary benefits while simultaneously removing the risk of market price fluctuations. The option theory is incorporated to formulate the contract price. The strike prices of options are derived from solving an equilibrium model in which both the buyer and the seller aim to maximise their own profit. Theoretical analysis shows that the proposed optional forward contract presents a more equitable and reasonable payoff structure that allows the buyer and seller to earn a larger overall expected benefit, and the contractual arrangement supports efficiency in economic dispatch of electricity production and consumption. The insights obtained from these results will be helpful to participants in the contractual decision-making process. (Author)

  18. Response of SII cortex to ipsilateral, contralateral and bilateral flutter stimulation in the cat

    Directory of Open Access Journals (Sweden)

    Favorov Oleg

    2005-02-01

    Full Text Available Abstract Background A distinctive property of SII is that it is the first cortical stage of the somatosensory projection pathway that integrates information arising from both sides of the body. However, there is very little known about how inputs across the body mid-line are processed within SII. Results Optical intrinsic signal imaging was used to evaluate the response of primary somatosensory cortex (SI and SII in the same hemisphere to 25 Hz sinusoidal vertical skin displacement stimulation ("skin flutter" applied contralaterally, ipsilaterally, and bilaterally to the central pads of the forepaws. A localized increase in absorbance in both SI and SII was evoked by both contralateral and bilateral flutter stimulation. Ipsilateral flutter stimulation evoked a localized increase in absorbance in SII, but not in SI. The SII region that responded with an increase in absorbance to ipsilateral stimulation was posterior to the region in which absorbance increased maximally in response to stimulation of the contralateral central pad. Additionally, in the posterior SII region that responded maximally to ipsilateral stimulation of the central pad, bilateral central pad stimulation approximated a linear summation of the SII responses to independent stimulation of the contralateral and ipsilateral central pads. Conversely, in anterior SII (the region that responded maximally to contralateral stimulation, bilateral stimulation was consistently less than the response evoked from the contralateral central pad. Conclusions The results indicate that two regions located at neighboring, but distinctly different A-P levels of the anterior ectosylvian gyrus process input from opposite sides of the body midline in very different ways. The results suggest that the SII cortex, in the cat, can be subdivided into at least two functionally distinct regions and that these functionally distinct regions demonstrate a laterality preference within SII.

  19. Electrical Stimulation Enhances Reinnervation After Nerve Injury

    OpenAIRE

    Willand, Michael P

    2015-01-01

    Electrical muscle stimulation following peripheral nerve injury has been a controversial method of treatment due primarily to the inconsistent literature surrounding it. In this presentation transcript I outline ongoing experiments investigating a clinically translatable daily muscle stimulation paradigm in rats following nerve injury. Results show that reinnervation of muscle and functional behavioural metrics are enhanced with daily stimulation with upregulation of intramuscular neurotrophi...

  20. Point Electric Stimulation and Children's Amblyopia

    Institute of Scientific and Technical Information of China (English)

    YAN Xing-ke; CHU Hui-ju; WANG Fu-chun; YANG Bo; GAO Yang; HAN Chou-ping

    2007-01-01

    To observe the therapeutic efficacy of electric stimulation on points for children's amblyopia.Method:Ninety children amblyopia cases with ametropia upon correction were randomized into three groups:point electric stimulation,comprehensive conventional therapy and integrative therapy of the above two.And then visual function changes of kids in the three groups were observed.Results:Among the above three therapies,the recovery rates of point electric stimulation,comprehensive conventional therapy and integrative therapy of the two were 83.9%,82.6%and 94.25 respectively,showing no significant difierence(P>0.05) among the three groups.Conclusion:Point electric stimulation has similar action with comprehensive conventional therapy in the treatment of children's amblyopia,and the combination of the two therapies has better effect,indicating point electric stimulation can speed up recovery of visual function of kids with amblyopia.

  1. The Polarity-Dependent Effects of the Bilateral Brain Stimulation on Working Memory

    OpenAIRE

    Keshvari, Fatemeh; Pouretemad, Hamid-Reza; Ekhtiari, Hamed

    2013-01-01

    Introduction Working memory plays a critical role in cognitive processes which are central to our daily life. Neuroimaging studies have shown that one of the most important areas corresponding to the working memory is the dorsolateral prefrontal cortex (DLFPC). This study was aimed to assess whether bilateral modulation of the DLPFC using a noninvasive brain stimulation, namely transcranial direct current stimulation (tDCS), modifies the working memory function in healthy adults. Methods In a...

  2. Transcranial electrical stimulation accelerates human sleep homeostasis.

    Directory of Open Access Journals (Sweden)

    Davide Reato

    Full Text Available The sleeping brain exhibits characteristic slow-wave activity which decays over the course of the night. This decay is thought to result from homeostatic synaptic downscaling. Transcranial electrical stimulation can entrain slow-wave oscillations (SWO in the human electro-encephalogram (EEG. A computational model of the underlying mechanism predicts that firing rates are predominantly increased during stimulation. Assuming that synaptic homeostasis is driven by average firing rates, we expected an acceleration of synaptic downscaling during stimulation, which is compensated by a reduced drive after stimulation. We show that 25 minutes of transcranial electrical stimulation, as predicted, reduced the decay of SWO in the remainder of the night. Anatomically accurate simulations of the field intensities on human cortex precisely matched the effect size in different EEG electrodes. Together these results suggest a mechanistic link between electrical stimulation and accelerated synaptic homeostasis in human sleep.

  3. A Short Term Therapy Approach to Processing Trauma: Art Therapy and Bilateral Stimulation

    Science.gov (United States)

    Tripp, Tally

    2007-01-01

    This article describes a dynamic, short-term art therapy approach that has been developed for the treatment of trauma related disorders. Using a modified Eye Movement Desensitization and Reprocessing (EMDR) protocol with alternating tactile and auditory bilateral stimulation, associations are rapidly brought to conscious awareness and expressed in…

  4. Electrical stimulation to accelerate wound healing

    Directory of Open Access Journals (Sweden)

    Gaurav Thakral

    2013-09-01

    Full Text Available Background: There are several applications of electrical stimulation described in medical literature to accelerate wound healing and improve cutaneous perfusion. This is a simple technique that could be incorporated as an adjunctive therapy in plastic surgery. The objective of this review was to evaluate the results of randomized clinical trials that use electrical stimulation for wound healing. Method: We identified 21 randomized clinical trials that used electrical stimulation for wound healing. We did not include five studies with treatment groups with less than eight subjects. Results: Electrical stimulation was associated with faster wound area reduction or a higher proportion of wounds that healed in 14 out of 16 wound randomized clinical trials. The type of electrical stimulation, waveform, and duration of therapy vary in the literature. Conclusion: Electrical stimulation has been shown to accelerate wound healing and increase cutaneous perfusion in human studies. Electrical stimulation is an adjunctive therapy that is underutilized in plastic surgery and could improve flap and graft survival, accelerate postoperative recovery, and decrease necrosis following foot reconstruction.

  5. Effects and mechanisms of gastrointestinal electrical stimulation on slow waves: a systematic canine study

    OpenAIRE

    Sun, Yan; Song, Geng-Qing; Yin, Jieyun; Lei, Yong; Chen, Jiande D.Z.

    2009-01-01

    The aims of this study were to determine optimal pacing parameters of electrical stimulation on different gut segments and to investigate effects and possible mechanisms of gastrointestinal electrical stimulation on gut slow waves. Twelve female hound-mix dogs were used in this study. A total of six pairs of electrodes were implanted on the stomach, duodenum, and ascending colon. Bilateral truncal vagotomy was performed in six of the dogs. One experiment was designed to study the effects of t...

  6. 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

  7. Bilateral subthalamic nucleus stimulation improves health-related quality of life in Parkinsonian patients.

    Science.gov (United States)

    Erola, Tuomo; Karinen, Petri; Heikkinen, Esa; Tuominen, Juho; Haapaniemi, Tarja; Koivukangas, John; Myllylä, Vilho

    2005-03-01

    Parkinson's disease (PD) is a common neurological disorder. Recently, bilateral deep brain stimulation (DBS) of the subthalamic nucleus (STN) has become an option in the treatment of severe PD. We measured the health-related quality of life (HRQoL) of 27 parkinsonian patients, who underwent a bilateral STN-operation. The instruments used for the evaluation of the HRQoL were the Parkinson's Disease Questionnaire (PDQ-39) and the Finnish version of the Nottingham Health Profile (NHP). We found that the quality of life significantly improved when measured with both HRQoL scales. Clinical improvement and improvement in HRQoL were positively correlated. PMID:15734666

  8. Electrodes for transcutaneous (surface) electrical stimulation

    OpenAIRE

    Keller Thierry; Kuhn Andreas

    2008-01-01

    In therapeutic and functional applications transcutaneous electrical stimulation (TES) is still the most frequently applied technique for muscle and nerve activation despite the huge efforts made to improve implantable technologies. Stimulation electrodes play the important role in interfacing the tissue with the stimulation unit. Between the electrode and the excitable tissue there are a number of obstacles in form of tissue resistivities and permittivities that can only be circumvented by m...

  9. Auricular electrical stimulation and dental pain threshold.

    OpenAIRE

    Simmons, M. S.; Oleson, T. D.

    1993-01-01

    A modified double-blind evaluation of naloxone reversibility of dental analgesia produced by auricular electrical stimulation (AES) was examined in 40 subjects assigned randomly to one of four groups: AES followed by saline (AS), AES followed by naloxone (AN), placebo AES followed by saline (PS), and placebo AES followed by naloxone (PN). Dental pain threshold was tested using a hand-held dental pulp tester. A second investigator administered the true or placebo AES using an electrical stimul...

  10. Impairments of motor-cortex responses to unilateral and bilateral direct current stimulation in schizophrenia

    Directory of Open Access Journals (Sweden)

    AlkomietHasan

    2013-10-01

    Full Text Available Transcranial direct current stimulation (tDCS is a non-invasive stimulation technique that can be applied to modulate cortical activity through induction of cortical plasticity. Since various neuropsychiatric disorders are characterised by fluctuations in cortical activity levels (e.g. schizophrenia, tDCS is increasingly investigated as a treatment tool. Several studies have shown that the induction of cortical plasticity following classical, unilateral tDCS is reduced or impaired in the stimulated and non-stimulated primary motor cortices (M1 of schizophrenia patients. Moreover, an alternative, bilateral tDCS setup has recently been shown to modulate cortical plasticity in both hemispheres in healthy subjects, highlighting another potential treatment approach. Here we present the first study comparing the efficacy of unilateral tDCS (cathode left M1, anode right supraorbital with simultaneous bilateral tDCS (cathode left M1, anode right M1 in schizophrenia patients. tDCS-induced cortical plasticity was monitored by investigating motor-evoked potentials induced by single-pulse transcranial magnetic stimulation applied to both hemispheres. Healthy subjects showed a reduction of left M1 excitability following unilateral tDCS on the stimulated left hemisphere and an increase in right M1 excitability following bilateral tDCS. In schizophrenia, no plasticity was induced following both stimulation paradigms. The pattern of these results indicates a complex interplay between plasticity and connectivity that is impaired in schizophrenia patients. Further studies are needed to clarify the biological underpinnings and clinical impact of these findings.

  11. 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.

  12. Bilateral somatosensory evoked potentials following intermittent theta-burst repetitive transcranial magnetic stimulation

    Directory of Open Access Journals (Sweden)

    Ziluk Angela

    2010-08-01

    Full Text Available Abstract Background Intermittent theta-burst stimulation (iTBS is a form of repetitive transcranial magnetic stimulation that may alter cortical excitability in the primary somatosensory cortex (SI. The present study investigated the effects of iTBS on subcortical and early cortical somatosensory evoked potentials (SEPs recorded over left, iTBS stimulated SI and the right-hemisphere non-stimulated SI. SEPs were recorded before and at 5, 15, and 25 minutes following iTBS. Results Compared to pre-iTBS, the amplitude of cortical potential N20/P25 was significantly increased for 5 minutes from non-stimulated SI and for 15 to 25 minutes from stimulated SI. Subcortical potentials recorded bilaterally remained unaltered following iTBS. Conclusion We conclude that iTBS increases the cortical excitability of SI bilaterally and does not alter thalamocortical afferent input to SI. ITBS may provide one avenue to induce cortical plasticity in the somatosensory cortex.

  13. 18F-FDG PET imaging on the neuronal network of Parkinson's disease patients following deep brain stimulation of bilateral subthalamic nucleus

    International Nuclear Information System (INIS)

    Objective: There is evidence that the cause and progression of Parkinson's disease (PD) may be attributed to subthalamic nucleus (STN) dysfunction and that external electrical stimulation of the STN may improve the underlying neuronal network. This study aimed at using 18F-FDG PET to monitor the functional status of the neuronal network of advanced PD patients following deep brain stimulation (DBS) of bilateral STN. Methods: Five PD patients in advanced stage, rated according to unified PD rat- ing scale (UPDRS) motion score, underwent bilateral STN DBS implantation. Six months after the implantation, each patient was studied with 18F-FDG PET scans under stimulation turned 'on' and 'off' conditions. Statistical parametric mapping 2 (SPM2) was applied for data analyses. Results: Bilateral STN DBS reduced glucose utilization in lentiform nucleus (globus pallidus), bilateral thalamus, cerebellum, as well as the distal parietal cortex. However, glucose utilization in midbrain and pons was increased. The PD-related pattern (PDRP) scores were significantly different during the 'on' status (2.12 ± 15.24) and 'off' status (4.93 ± 13.01), which corresponded to the clinical improvement of PD symptoms as PDRP scores decreased. Conclusion: 18F-FDG PET may be useful in monitoring and mapping the metabolism of the neuronal network during bilateral STN DBS, thus supporting its therapeutic impact on PD patients. (authors)

  14. Electrical stimulation of experimental nonunions

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, R.R.; Luethi, U.; Dueland, R.T.; Perren, S.M.

    Hypertrophic and oligotrophic nonunions were prepared by resection of a portion of the proximal ulna in dogs. In the hypertrophic nonunions, 20 muamps of direct current for eight weeks produced an increase in bone formation compared to the opposite control limb by radiography, photometry, point counting of new bone, and growth rate by sequential fluorochrome labeling and the dynamic uptake of 99mTc-labeled methylene disphosphonate. Oligotrophic nonunions were treated by plating and aspiration grafting in addition to direct-current stimulation. Ony the point counting of new bone showed a significant increase in bone formation with stimulation. Sequential fluorochrome labeling demonstrated that the new bone was laid down on existing bone and not primarily adjacent to the cathode within the fibrous nonunion. This finding supports the cell-mediated rather than physicochemical effect of electrostimulation.

  15. Electrical stimulation of experimental nonunions

    International Nuclear Information System (INIS)

    Hypertrophic and oligotrophic nonunions were prepared by resection of a portion of the proximal ulna in dogs. In the hypertrophic nonunions, 20 muamps of direct current for eight weeks produced an increase in bone formation compared to the opposite control limb by radiography, photometry, point counting of new bone, and growth rate by sequential fluorochrome labeling and the dynamic uptake of 99mTc-labeled methylene disphosphonate. Oligotrophic nonunions were treated by plating and aspiration grafting in addition to direct-current stimulation. Ony the point counting of new bone showed a significant increase in bone formation with stimulation. Sequential fluorochrome labeling demonstrated that the new bone was laid down on existing bone and not primarily adjacent to the cathode within the fibrous nonunion. This finding supports the cell-mediated rather than physicochemical effect of electrostimulation

  16. Sensitivity to thermal stimulation in prairie rattlesnakes (Crotalus viridis) after bilateral anesthetization of the facial pits

    Energy Technology Data Exchange (ETDEWEB)

    Chiszar, D.; Dickman, D.; Colton, J.

    1986-01-01

    Six yearling prairie rattlesnakes (Crotalus viridis) were exposed to thermal stimuli prior to and after bilateral anesthetization of their facial pits with 2% xylocaine solution. This treatment eliminates trigeminally mediated electrophysiological responses of the pits to thermal stimulation. Nevertheless, the rattlesnakes continued to exhibit behavioral responses to thermal cues after anesthetization of the pits. An auxiliary infrared-sensitive system, nociceptors, or the common temperature sense could be responsible for these findings.

  17. Multi-microphone adaptive noise reduction strategies for coordinated stimulation in bilateral cochlear implant devices

    OpenAIRE

    Kokkinakis, Kostas; Loizou, Philipos C.

    2010-01-01

    Bilateral cochlear implant (BI-CI) recipients achieve high word recognition scores in quiet listening conditions. Still, there is a substantial drop in speech recognition performance when there is reverberation and more than one interferers. BI-CI users utilize information from just two directional microphones placed on opposite sides of the head in a so-called independent stimulation mode. To enhance the ability of BI-CI users to communicate in noise, the use of two computationally inexpensi...

  18. Impairment of aversive memory reconsolidation by localized intracranial electrical stimulation.

    Science.gov (United States)

    Stehberg, Jimmy; Levy, Dino; Zangen, Abraham

    2009-03-01

    Reconsolidation of long-term memory is blocked in animal models by macromolecular synthesis inhibitors, resulting in item-specific post-retrieval amnesia. The induction of such amnesia could ameliorate traumatic memories and phobias. However, this pharmacological approach is of limited value in humans because of toxicity. Here we report that reconsolidation of conditioned taste aversion in the rat is impaired by localized intracranial electrical stimulation. Lasting impairment was obtained only when stimulation was applied during memory reactivation and only to the dysgranular insular cortex bilaterally, which subserves the memory, but not to adjacent brain sites. The ability to learn a new association was not affected. The same method blocked new memory consolidation, but produced anterograde amnesia, reminiscent of the known effect of non-localized electroconvulsive therapy. Our results suggest that localized electrical microstimulation, such as produced by deep-brain stimulation or deep transcranial magnetic stimulation, could be used to impair long-term memory if applied during memory reactivation, and could lead to the development of a novel treatment for intractable post-traumatic stress disorder. PMID:19200060

  19. Pitch discrimination of patterned electric stimulation

    OpenAIRE

    Chen, H B; Ishihara, Y C; Zeng, F G

    2005-01-01

    One reason for the poor pitch performance in current cochlear-implant users may be the highly synchronized neural firing in electric hearing that lacks stochastic properties of neural firing in normal acoustic hearing. This study used three different electric stimulation patterns, jittered, probabilistic, and auditory-model-generated pulses, to mimic some aspects of the normal neural firing pattern in acoustic hearing. Pitch discrimination was measured at standard frequencies of 100, 250, 500...

  20. Electrical Stimulation as an Aid to Speechreading.

    Science.gov (United States)

    Tyler, Richard S.; And Others

    1988-01-01

    This paper, discussing use of electrical stimulation by postlingually deafened adults to supplement speechreading, focuses on: information conveyed by vision, acoustic information needed to resolve visual confusions, basic psychophysical abilities of cochlear implant patients, auditory-alone and audiovisual perception by cochlear-implant patients,…

  1. Chronic bilateral thalamic stimulation: a new therapeutic approach in intractable Tourette syndrome. Report of three cases.

    Science.gov (United States)

    Visser-Vandewalle, Veerle; Temel, Yasin; Boon, Peter; Vreeling, Fred; Colle, Henry; Hoogland, Govert; Groenewegen, Henk J; van der Linden, Chris

    2003-12-01

    Based on the results of thalamotomies described by Hassler in 1970, the authors performed bilateral thalamic high-frequency stimulation (HFS) in three patients with intractable Tourette syndrome (TS). In this report they describe the long-term effects. Three male patients (42, 28, and 45 years of age) had manifested motor and vocal tics since early childhood. The diagnosis of TS was made according to the criteria of the Tourette Syndrome Classification Study Group. Any drug or alternative treatment had been either ineffective or only temporarily effective in all three patients. There was no serious comorbidity. The target for stimulation was chosen at the level of the centromedian nucleus, substantia periventricularis, and nucleus ventrooralis internus. After 2 weeks of test stimulation, the pulse generators were implanted. After a follow-up period of 5 years in the patient in Case 1, 1 year in the patient in Case 2, and 8 months in the patient in Case 3, all major motor and vocal tics had disappeared and no serious complications had occurred. When stimulation was applied at the voltage necessary to achieve an optimal result on the tics, a slight sedative effect was noted in all three patients. In the patients in Cases 1 and 3 there were stimulation-induced changes in sexual behavior. Chronic thalamic HFS may be an effective and safe treatment for medically intractable TS in adult patients. Unwanted stimulation-induced side effects may occur. PMID:14705742

  2. Electric Conductivity of Carbon Nanoparticles Stimulated by Electric Field

    International Nuclear Information System (INIS)

    Host-guest interactions can be the unique method of spin manipulation in nanoscale. Strong changes in spin localization are generated when potential barriers between nanographitic units of activated carbon fibers are modified by interaction with adsorbed molecules. Stronger modifications occur when dipolar guest molecules are stimulated with external electric field. We report experimental results which show the influence of electric field on the spin localization in activated carbon fibers. (authors)

  3. FDG-PET study of the bilateral subthalamic nucleus stimulation effects on the regional cerebral metabolism in advanced Parkinson disease

    International Nuclear Information System (INIS)

    The aim of the study was to evaluate the changes in regional cerebral metabolic rate of glucose (rCMRGIu) induced by bilateral subthalamic nucleus (STN) stimulation in advanced Parkinson's disease (PD). 18F-Fluorodeoxyglucose (FDG) PET data obtained before and one month after stimulation were analyzed with statistical parametric mapping (SPM). As a result of clinically effective bilateral STN stimulation, rCMRGIu increased in lateral globus pallidus (GP), upper brain stem, dorsolateral prefrontal cortex (DLPFC) and posterior parietal-occipital cortex, and decreased in the orbital frontal cortex and parahippocampus gyrus (p <0.001). We conclude that the alleviation of clinical symptoms in advanced PD by bilateral STN stimulation may be the result of activation of both ascending and descending pathways from STN and of restoration of the impaired higher-order cortex functions. (author)

  4. 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

  5. Transdermal electrical stimulation in sensorineural tinnitus

    OpenAIRE

    S Maini; Deoganonkar, S. C.

    1999-01-01

    In 73 patients, comprising of 84 ears, with persistent decompensated tinnitus and sensorineu-ral deafness, tinnitus suppression was attempted with low frequency, low ampere transdermal electrical stimula-tion (TDES). The causes of tinnitus were presbyacusis, unknown aetiology, noise exposure, otosclerosis, ototoxic drugs, endolymphatic hydrops, labyrinthitis and post head injury. Reduction of tinnitus was achieved in 38 of 84 ears. Results i.e. improvement were achieved in patients in the fol...

  6. Effects of Anodal High-Definition Transcranial Direct Current Stimulation on Bilateral Sensorimotor Cortex Activation During Sequential Finger Movements: An fNIRS Study.

    Science.gov (United States)

    Muthalib, Makii; Besson, Pierre; Rothwell, John; Ward, Tomas; Perrey, Stephane

    2016-01-01

    Transcranial direct current stimulation (tDCS) is a non-invasive electrical brain stimulation technique that can modulate cortical neuronal excitability and activity. This study utilized functional near infrared spectroscopy (fNIRS) neuroimaging to determine the effects of anodal high-definition (HD)-tDCS on bilateral sensorimotor cortex (SMC) activation. Before (Pre), during (Online), and after (Offline) anodal HD-tDCS (2 mA, 20 min) targeting the left SMC, eight healthy subjects performed a simple finger sequence (SFS) task with their right or left hand in an alternating blocked design (30-s rest and 30-s SFS task, repeated five times). In order to determine the level of bilateral SMC activation during the SFS task, an Oxymon MkIII fNIRS system was used to measure from the left and right SMC, changes in oxygenated (O2Hb) and deoxygenated (HHb) haemoglobin concentration values. The fNIRS data suggests a finding that compared to the Pre condition both the "Online" and "Offline" anodal HD-tDCS conditions induced a significant reduction in bilateral SMC activation (i.e., smaller decrease in HHb) for a similar motor output (i.e., SFS tap rate). These findings could be related to anodal HD-tDCS inducing a greater efficiency of neuronal transmission in the bilateral SMC to perform the same SFS task. PMID:26782232

  7. 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.

  8. 21 CFR 868.2775 - Electrical peripheral nerve stimulator.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Electrical peripheral nerve stimulator. 868.2775... (CONTINUED) MEDICAL DEVICES ANESTHESIOLOGY DEVICES Monitoring Devices § 868.2775 Electrical peripheral nerve stimulator. (a) Identification. An electrical peripheral nerve stimulator (neuromuscular blockade monitor)...

  9. 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…

  10. Electrodes for transcutaneous (surface electrical stimulation

    Directory of Open Access Journals (Sweden)

    Keller Thierry

    2008-01-01

    Full Text Available In therapeutic and functional applications transcutaneous electrical stimulation (TES is still the most frequently applied technique for muscle and nerve activation despite the huge efforts made to improve implantable technologies. Stimulation electrodes play the important role in interfacing the tissue with the stimulation unit. Between the electrode and the excitable tissue there are a number of obstacles in form of tissue resistivities and permittivities that can only be circumvented by magnetic fields but not by electric fields and currents. However, the generation of magnetic fields needed for the activation of excitable tissues in the human body requires large and bulky equipment. TES devices on the other hand can be built cheap, small and light weight. The weak part in TES is the electrode that cannot be brought close enough to the excitable tissue and has to fulfill a number of requirements to be able to act as efficient as possible. The present review article summarizes the most important factors that influence efficient TES, presents and discusses currently used electrode materials, designs and configurations, and points out findings that have been obtained through modeling, simulation and testing.

  11. Global perception depends on coherent work of bilateral visual cortices:Transcranial magnetic stimulation (TMS) studies

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Previous research suggests that the right and left hemispheres dominate global and local perception of hierarchical patterns, respectively. The current work examined whether global perception of hierarchi-cal stimuli requires coherent work of bilateral visual cortices using transcranial magnetic stimulation (TMS). Subjects discriminated global or local properties of compound letters in Experiment 1. Reaction times were recorded when single-pulse real TMS or sham TMS was delivered over the left or right visual cortex. While a global precedence effect (i.e., faster responses to global than local targets and stronger global-to-local interference than the reverse) was observed, TMS decreased global-to-local interference whereas increased local-to-global interference. Experiment 2 ruled out the possibility that the effects observed in Experiment 1 resulted from perceptual learning. Experiment 3 used compound shapes and observed TMS effect similar to that in Experiment 1. Moreover, TMS also slowed global RTs whereas speeded up local RTs in Experiment 3. Finally, the TMS effects observed in Experiments 1 and 3 did not differ between the conditions when TMS was applied over the left and right hemispheres. The results support a coherence hypothesis that global perception of compound stimuli depends upon the co-herent work of bilateral visual cortices.

  12. Global perception depends on coherent work of bilateral visual cortices: Transcranial magnetic stimulation (TMS) studies

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xin; HAN ShiHui

    2007-01-01

    Previous research suggests that the right and left hemispheres dominate global and local perception of hierarchical patterns, respectively. The current work examined whether global perception of hierarchical stimuli requires coherent work of bilateral visual cortices using transcranial magnetic stimulation(TMS). Subjects discriminated global or local properties of compound letters in Experiment 1. Reaction times were recorded when single-pulse real TMS or sham TMS was delivered over the left or right visual cortex. While a global precedence effect (i.e., faster responses to global than local targets and stronger global-to-local interference than the reverse) was observed, TMS decreased global-to-local interference whereas increased local-to-global interference. Experiment 2 ruled out the possibility that the effects observed in Experiment 1 resulted from perceptual learning. Experiment 3 used compound shapes and observed TMS effect similar to that in Experiment 1. Moreover, TMS also slowed global RTs whereas speeded up local RTs in Experiment 3. Finally, the TMS effects observed in Experiments 1 and 3 did not differ between the conditions when TMS was applied over the left and right hemispheres. The results support a coherence hypothesis that global perception of compound stimuli depends upon the coherent work of bilateral visual cortices.

  13. Electrical vestibular stimulation after vestibular deafferentation and in vestibular schwannoma.

    Directory of Open Access Journals (Sweden)

    Swee Tin Aw

    Full Text Available BACKGROUND: Vestibular reflexes, evoked by human electrical (galvanic vestibular stimulation (EVS, are utilized to assess vestibular function and investigate its pathways. Our study aimed to investigate the electrically-evoked vestibulo-ocular reflex (eVOR output after bilateral and unilateral vestibular deafferentations to determine the characteristics for interpreting unilateral lesions such as vestibular schwannomas. METHODS: EVOR was recorded with dual-search coils as binocular three-dimensional eye movements evoked by bipolar 100 ms-step at EVS intensities of [0.9, 2.5, 5.0, 7.5, 10.0] mA and unipolar 100 ms-step at 5 mA EVS intensity. Five bilateral vestibular deafferented (BVD, 12 unilateral vestibular deafferented (UVD, four unilateral vestibular schwannoma (UVS patients and 17 healthy subjects were tested with bipolar EVS, and five UVDs with unipolar EVS. RESULTS: After BVD, bipolar EVS elicited no eVOR. After UVD, bipolar EVS of one functioning ear elicited bidirectional, excitatory eVOR to cathodal EVS with 9 ms latency and inhibitory eVOR to anodal EVS, opposite in direction, at half the amplitude with 12 ms latency, exhibiting an excitatory-inhibitory asymmetry. The eVOR patterns from UVS were consistent with responses from UVD confirming the vestibular loss on the lesion side. Unexpectedly, unipolar EVS of the UVD ear, instead of absent response, evoked one-third the bipolar eVOR while unipolar EVS of the functioning ear evoked half the bipolar response. CONCLUSIONS: The bidirectional eVOR evoked by bipolar EVS from UVD with an excitatory-inhibitory asymmetry and the 3 ms latency difference between normal and lesion side may be useful for detecting vestibular lesions such as UVS. We suggest that current spread could account for the small eVOR to 5 mA unipolar EVS of the UVD ear.

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

    DEFF Research Database (Denmark)

    Barsi, Gergely Istvan; Popovic, Dejan B.; Tarkka, Ina M.; Sinkjær, Thomas; Grey, Michael J

    2008-01-01

    Rehabilitation with augmented electrical stimulation can enhance functional recovery after stroke, and cortical plasticity may play a role in this process. The purpose of this study was to compare the effects of three training paradigms on cortical excitability in healthy subjects. Cortical......) 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 the...

  15. Deep Brain Electrical Stimulation in Epilepsy

    Science.gov (United States)

    Rocha, Luisa L.

    2008-11-01

    The deep brain electrical stimulation has been used for the treatment of neurological disorders such as Parkinson's disease, chronic pain, depression and epilepsy. Studies carried out in human brain indicate that the application of high frequency electrical stimulation (HFS) at 130 Hz in limbic structures of patients with intractable temporal lobe epilepsy abolished clinical seizures and significantly decreased the number of interictal spikes at focus. The anticonvulsant effects of HFS seem to be more effective in patients with less severe epilepsy, an effect associated with a high GABA tissue content and a low rate of cell loss. In addition, experiments using models of epilepsy indicate that HFS (pulses of 60 μs width at 130 Hz at subthreshold current intensity) of specific brain areas avoids the acquisition of generalized seizures and enhances the postictal seizure suppression. HFS is also able to modify the status epilepticus. It is concluded that the effects of HFS may be a good strategy to reduce or avoid the epileptic activity.

  16. Multi-microphone adaptive noise reduction strategies for coordinated stimulation in bilateral cochlear implant devices.

    Science.gov (United States)

    Kokkinakis, Kostas; Loizou, Philipos C

    2010-05-01

    Bilateral cochlear implant (BI-CI) recipients achieve high word recognition scores in quiet listening conditions. Still, there is a substantial drop in speech recognition performance when there is reverberation and more than one interferers. BI-CI users utilize information from just two directional microphones placed on opposite sides of the head in a so-called independent stimulation mode. To enhance the ability of BI-CI users to communicate in noise, the use of two computationally inexpensive multi-microphone adaptive noise reduction strategies exploiting information simultaneously collected by the microphones associated with two behind-the-ear (BTE) processors (one per ear) is proposed. To this end, as many as four microphones are employed (two omni-directional and two directional) in each of the two BTE processors (one per ear). In the proposed two-microphone binaural strategies, all four microphones (two behind each ear) are being used in a coordinated stimulation mode. The hypothesis is that such strategies combine spatial information from all microphones to form a better representation of the target than that made available with only a single input. Speech intelligibility is assessed in BI-CI listeners using IEEE sentences corrupted by up to three steady speech-shaped noise sources. Results indicate that multi-microphone strategies improve speech understanding in single- and multi-noise source scenarios. PMID:21117762

  17. Changes in handwriting resulting from bilateral high-frequency stimulation of the subthalamic nucleus in Parkinson's disease.

    Science.gov (United States)

    Siebner, H R; Ceballos-Baumann, A; Standhardt, H; Auer, C; Conrad, B; Alesch, F

    1999-11-01

    High-frequency stimulation of the subthalamic nucleus (STN) is a promising therapeutic approach in patients with severely disabling Parkinson's disease (PD). Whereas STN stimulation improves the cardinal signs of PD, little is known about the effects of STN stimulation on fine manual skills like handwriting. Therefore, the present study investigated the changes in handwriting during bilateral STN stimulation in 12 patients with advanced PD. Dopaminergic medication was discontinued at least 12 hours before the study. The patients were asked to write a standardized sentence repetitively. Five samples of the patient's script were recorded during effective bilateral STN stimulation and 1 hour after both stimulators had been switched off. The movements of the tip of the pencil were recorded using a digitizing tablet. Handwriting movements were segmented into subsequent up- and down-strokes, and a stroke-based kinematic analysis of handwriting was performed. During high-frequency STN stimulation, handwriting movements became faster and smoother indicating a partial restoration of an "open-loop" automatic performance. In addition, STN stimulation gave rise to a significant increase in the mean vertical stroke length demonstrating a stimulation-related reduction in micrographia. The present data underscores the importance of the STN in "open-loop" performance of highly skilled sequential hand movements. PMID:10584671

  18. 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

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

    OpenAIRE

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

    2015-01-01

    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 ele...

  20. Short and long term outcome of bilateral pallidal stimulation in chorea-acanthocytosis.

    Directory of Open Access Journals (Sweden)

    Marie Miquel

    Full Text Available BACKGROUND: Chorea-acanthocytosis (ChAc is a neuroacanthocytosis syndrome presenting with severe movement disorders poorly responsive to drug therapy. Case reports suggest that bilateral deep brain stimulation (DBS of the ventro-postero-lateral internal globus pallidus (GPi may benefit these patients. To explore this issue, the present multicentre (n=12 retrospective study collected the short and long term outcome of 15 patients who underwent DBS. METHODS: Data were collected in a standardized way 2-6 months preoperatively, 1-5 months (early and 6 months or more (late after surgery at the last follow-up visit (mean follow-up: 29.5 months. RESULTS: Motor severity, assessed by the Unified Huntington's Disease Rating Scale-Motor Score, UHDRS-MS, was significantly reduced at both early and late post-surgery time points (mean improvement 54.3% and 44.1%, respectively. Functional capacity (UHDRS-Functional Capacity Score was also significantly improved at both post-surgery time points (mean 75.5% and 73.3%, respectively, whereas incapacity (UHDRS-Independence Score improvement reached significance at early post-surgery only (mean 37.3%. Long term significant improvement of motor symptom severity (≥ 20 % from baseline was observed in 61.5 % of the patients. Chorea and dystonia improved, whereas effects on dysarthria and swallowing were variable. Parkinsonism did not improve. Linear regression analysis showed that preoperative motor severity predicted motor improvement at both post-surgery time points. The most serious adverse event was device infection and cerebral abscess, and one patient died suddenly of unclear cause, 4 years after surgery. CONCLUSION: This study shows that bilateral DBS of the GPi effectively reduces the severity of drug-resistant hyperkinetic movement disorders such as present in ChAc.

  1. Relationships between Electrically Evoked Potentials and Loudness Growth in Bilateral Cochlear Implant Users

    OpenAIRE

    Kirby, Benjamin; Brown, Carolyn; Abbas, Paul; Etler, Christine; O’Brien, Sara

    2012-01-01

    Bilateral cochlear implantation has motivated efforts to ensure that sounds presented at equal levels to each ear are perceived as equally loud. Psychophysical loudness balancing is not always practical, especially with pediatric users. Electrophysiological potentials -- electrically evoked auditory brain stem response (EABR) and electrically evoked compound action potential (ECAP) measures -- may provide a means of approximating loudness balance. It was hypothesized that stimuli evoking equa...

  2. Surface electrical stimulation to evoke referred sensation.

    Science.gov (United States)

    Forst, Johanna C; Blok, Derek C; Slopsema, Julia P; Boss, John M; Heyboer, Lane A; Tobias, Carson M; Polasek, Katharine H

    2015-01-01

    Surface electrical stimulation (SES) is being investigated as a noninvasive method to evoke natural sensations distal to electrode location. This may improve treatment for phantom limb pain as well as provide an alternative method to deliver sensory feedback. The median and/or ulnar nerves of 35 subjects were stimulated at the elbow using surface electrodes. Strength-duration curves of hand sensation were found for each subject. All subjects experienced sensation in their hand, which was mostly described as a paresthesia-like sensation. The rheobase and chronaxie values were found to be lower for the median nerve than the ulnar nerve, with no significant difference between sexes. Repeated sessions with the same subject resulted in sufficient variability to suggest that recalculating the strength-duration curve for each electrode placement is necessary. Most of the recruitment curves in this study were generated with 28 to 36 data points. To quickly reproduce these curves with limited increase in error, we recommend 10 data points. Future studies will focus on obtaining different sensations using SES with the strength-duration curve defining the threshold of the effective parameter space. PMID:26348194

  3. Frequency dependence of behavioral modulation by hippocampal electrical stimulation

    OpenAIRE

    La Corte, Giorgio; Wei, Yina; Chernyy, Nick; Gluckman, Bruce J.; Schiff, Steven J.

    2013-01-01

    Electrical stimulation offers the potential to develop novel strategies for the treatment of refractory medial temporal lobe epilepsy. In particular, direct electrical stimulation of the hippocampus presents the opportunity to modulate pathological dynamics at the ictal focus, although the neuroanatomical substrate of this region renders it susceptible to altering cognition and affective processing as a side effect. We investigated the effects of three electrical stimulation paradigms on sepa...

  4. Epidural spinal electrical stimulation in severe angina pectoris.

    OpenAIRE

    Mannheimer, C; Augustinsson, L E; Carlsson, C A; Manhem, K; Wilhelmsson, C

    1988-01-01

    The short term effects of epidural spinal electrical stimulation were studied in 10 patients with angina pectoris of New York Heart Association functional class III or IV. The antianginal pharmacological treatment given at entry to the study was regarded as optimal and was not changed during the study. The effects of epidural spinal electrical stimulation were measured by repeated bicycle ergometer tests. Treatment with epidural spinal electrical stimulation increased the patients' working ca...

  5. The Neural Correlates of Long-Term Carryover following Functional Electrical Stimulation for Stroke.

    Science.gov (United States)

    Gandolla, Marta; Ward, Nick S; Molteni, Franco; Guanziroli, Eleonora; Ferrigno, Giancarlo; Pedrocchi, Alessandra

    2016-01-01

    Neurorehabilitation effective delivery for stroke is likely to be improved by establishing a mechanistic understanding of how to enhance adaptive plasticity. Functional electrical stimulation is effective at reducing poststroke foot drop; in some patients, the effect persists after therapy has finished with an unknown mechanism. We used fMRI to examine neural correlates of functional electrical stimulation key elements, volitional intent to move and concurrent stimulation, in a group of chronic stroke patients receiving functional electrical stimulation for foot-drop correction. Patients exhibited task-related activation in a complex network, sharing bilateral sensorimotor and supplementary motor activation with age-matched controls. We observed consistent separation of patients with and without carryover effect on the basis of brain responses. Patients who experienced the carryover effect had responses in supplementary motor area that correspond to healthy controls; the interaction between experimental factors in contralateral angular gyrus was seen only in those without carryover. We suggest that the functional electrical stimulation carryover mechanism of action is based on movement prediction and sense of agency/body ownership-the ability of a patient to plan the movement and to perceive the stimulation as a part of his/her own control loop is important for carryover effect to take place. PMID:27073701

  6. The Neural Correlates of Long-Term Carryover following Functional Electrical Stimulation for Stroke

    Directory of Open Access Journals (Sweden)

    Marta Gandolla

    2016-01-01

    Full Text Available Neurorehabilitation effective delivery for stroke is likely to be improved by establishing a mechanistic understanding of how to enhance adaptive plasticity. Functional electrical stimulation is effective at reducing poststroke foot drop; in some patients, the effect persists after therapy has finished with an unknown mechanism. We used fMRI to examine neural correlates of functional electrical stimulation key elements, volitional intent to move and concurrent stimulation, in a group of chronic stroke patients receiving functional electrical stimulation for foot-drop correction. Patients exhibited task-related activation in a complex network, sharing bilateral sensorimotor and supplementary motor activation with age-matched controls. We observed consistent separation of patients with and without carryover effect on the basis of brain responses. Patients who experienced the carryover effect had responses in supplementary motor area that correspond to healthy controls; the interaction between experimental factors in contralateral angular gyrus was seen only in those without carryover. We suggest that the functional electrical stimulation carryover mechanism of action is based on movement prediction and sense of agency/body ownership—the ability of a patient to plan the movement and to perceive the stimulation as a part of his/her own control loop is important for carryover effect to take place.

  7. New controller for functional electrical stimulation systems.

    Science.gov (United States)

    Fisekovic, N; Popovic, D B

    2001-07-01

    A novel, self-contained controller for functional electrical stimulation systems has been designed. The development was motivated by the need to have a general purpose, easy to use controller capable of stimulating many muscle groups, thus restoring complex motor functions (e.g. standing, walking, reaching, and grasping). The designed controller can regulate the frequency, pulse duration, and charge balance on up to 16 channels, and execute pre-programmed and sensory-driven control operations. The controller supports up to eight analog and six digital sensors, and comprises a memory block for including history of the sensory data (time series). Five independent timers provide the basis for the multi-modal and multi-level control of movement. The PC compatible interface is realised via an IR serial communication channel. The PC based software is user friendly and fully menu driven. This paper also presents a case study where the controller was implemented to restore walking in a paraplegic subject. The assistive system comprised the novel controller, the power and output stages of an eight-channel FES system (IEEE Trans Rehabil Eng, TRE-2 (1994) 234), ankle-foot orthoses, and a rolling walker. Stimulation was applied with surface electrodes positioned over the motoneurons that innervate muscles responsible for the hip and knee flexion and extension. The sensory system included goniometers at knee and hip joints, force-sensing resistors built in the shoe insoles, and digital accelerometers at the hips. A rule-based control algorithm was generated following a two-step procedure: (1) simulation and (2) machine learning as described in earlier studies (IEEE Trans Rehab Eng, TRE-7 (1999) 69). The paraplegic subject walked faster, and with less physiological effort, when automatic control was applied as compared to hand-control. This case study, as well as a previous one for assisting grasping (The design and testing of a new programmable electronic stimulator. N

  8. Strategic evaluation of bilateral contract for electricity retailer in restructured power market

    International Nuclear Information System (INIS)

    In a competitive market scenario, consumers make payments for the consumption of electricity to retailers at fixed tariff. The retailers buy power at the Market Clearing Price (MCP) in spot market and/or through bilateral contract at agreed upon price. Due to these different modes at buying and selling ends, the retailers are faced with an involved task of estimating their payoffs along with the risk-quantification. The methodology presented in this paper gives a range of bilateral quantity and associated price for a retailer to ensure risk-constrained payoff. The exercise is carried out with a single retailer in the market as well as for a case of competition amongst two retailers. Risk is quantified using Risk Adjusted Recovery on Capital (RAROC). The problem is evaluated to get a range of bilateral quantity to be quoted for a particular bilateral price at fixed tariff of loyal load and fixed value of switching load. This summary combined with risk-averseness of the retailer leads him to make a judicial choice about bilateral transactions such that it leads to a risk-constrained payoff. (author)

  9. Gastric Electrical Stimulation: A Novel Treatment for Gastroparesis

    OpenAIRE

    Jordan, Corinne; Shapsis, Alexander; de Csepel, John

    2005-01-01

    Presented herein is a case report of a laparoscopic gastric electrical stimulator implantation for drug-refractory gastroparesis. Technical aspects of the procedure, as well as a review of the existing literature, are discussed. Gastric electrical stimulation offers a new alternative for the treatment of drug-refractory gastroparesis.

  10. Electrical stimulation: a reflection on current clinical practices.

    Science.gov (United States)

    Bertoti, D B

    2000-01-01

    This paper briefly reviews the basic principles of several clinical applications of electrical stimulation for therapeutic purposes. It is intended to facilitate the integration of electrical stimulation into routine clinical practice by clarifying the terminology and standard conventions of the field, explaining the delivery capabilities of common electrical stimulators commercially available for clinical use, summarizing several examples of evidence-based therapeutic applications, and providing guidelines for selection of most commonly used treatment parameters. Rather than an exhaustive survey of the field, the presentation touches broadly on guidelines for use of transcutaneous electrical stimulation employing surface electrodes for the purposes of analgesia (TENS), drug delivery (iontophoresis), or neuromuscular rehabilitation (NMES), as well as other selected clinical applications. The paper is a general review of common clinical practices of electrotherapy and should serve as an introduction to the important factors for clinicians to consider when contemplating electrical stimulation as a treatment option. PMID:11067575

  11. Bilateral Transcranial Direct Current Stimulation Language Treatment Enhances Functional Connectivity in the Left Hemisphere: Preliminary Data from Aphasia.

    Science.gov (United States)

    Marangolo, Paola; Fiori, Valentina; Sabatini, Umberto; De Pasquale, Giada; Razzano, Carmela; Caltagirone, Carlo; Gili, Tommaso

    2016-05-01

    Several studies have already shown that transcranial direct current stimulation (tDCS) is a useful tool for enhancing recovery in aphasia. However, no reports to date have investigated functional connectivity changes on cortical activity because of tDCS language treatment. Here, nine aphasic persons with articulatory disorders underwent an intensive language therapy in two different conditions: bilateral anodic stimulation over the left Broca's area and cathodic contralesional stimulation over the right homologue of Broca's area and a sham condition. The language treatment lasted 3 weeks (Monday to Friday, 15 sessions). In all patients, language measures were collected before (T0) and at the end of treatment (T15). Before and after each treatment condition (real vs. sham), each participant underwent a resting-state fMRI study. Results showed that, after real stimulation, patients exhibited the greatest recovery not only in terms of better accuracy in articulating the treated stimuli but also for untreated items on different tasks of the language test. Moreover, although after the sham condition connectivity changes were confined to the right brain hemisphere, real stimulation yielded to stronger functional connectivity increase in the left hemisphere. In conclusion, our data provide converging evidence from behavioral and functional imaging data that bilateral tDCS determines functional connectivity changes within the lesioned hemisphere, enhancing the language recovery process in stroke patients. PMID:26807842

  12. Perceiving electrical stimulation of identified human visual areas

    OpenAIRE

    Murphey, Dona K.; Maunsell, John H. R.; Beauchamp, Michael S.; Yoshor, Daniel

    2009-01-01

    We studied whether detectable percepts could be produced by electrical stimulation of intracranial electrodes placed over human visual areas identified with fMRI. Identification of areas was confirmed by recording local-field potentials from the electrode, such as face-selective electrical responses from electrodes over the fusiform face area (FFA). The probability of detecting electrical stimulation of a visual area varied with the position of the area in the visual cortical hierarchy. Stimu...

  13. Functional electrical stimulation on paraplegic patients

    Directory of Open Access Journals (Sweden)

    Helmut Kern

    2014-07-01

    Full Text Available We report on clinical and physiological effects of 8 months Functional Electrical Stimulation (FES of quadriceps femoris muscle on 16 paraplegic patients. Each patient had muscle biopsies, CT-muscle diameter measurements, knee extension strength testing carried out before and after 8 months FES training. Skin perfusion was documented through infrared telethermography and xenon clearance, muscle perfusion was recorded through thallium scintigraphy. After 8 months FES training baseline skin perfusion showed 86 % increase, muscle perfusion was augmented by 87 %. Muscle fiber diameters showed an average increase of 59 % after 8 months FES training. Muscles in patients with spastic paresis as well as in patients with denervation showed an increase in aerob and anaerob muscle enzymes up to the normal range. Even without axonal neurotropic substances FES was able to demonstrate fiberhypertrophy, enzyme adaptation and intracellular structural benefits in denervated muscles. The increment in muscle area as visible on CT-scans of quadriceps femoris was 30 % in spastic paraplegia and 10 % in denervated patients respectively. FES induced changes were less in areas not directly underneath the surface electrodes. We strongly recommend the use of Kern`s current for FES in denervated muscles to induce tetanic muscle contractions as we formed a very critical opinion of conventional exponential current. In patients with conus-cauda-lesions FES must be integrated into modern rehabilitation to prevent extreme muscle degeneration and decubital ulcers. Using FES we are able to improve metabolism and induce positive trophic changes in our patients lower extremities. In spastic paraplegics the functions „rising and walking“ achieved through FES are much better training than FES ergometers. Larger muscle masses are activated and an increased heart rate is measured, therefore the impact on cardiovascular fitness and metabolism is much greater. This effectively

  14. Electromyographic evaluation of functional electrical stimulation to injured oculomotor nerve

    Institute of Scientific and Technical Information of China (English)

    Min Yang; Shiting Li; Youqiang Meng; Ningxi Zhu; Xuhui Wang; Liang Wan; Wenchuan Zhang; Jun Zhong; Shugan Zhu; Massimiliano Visocchi

    2011-01-01

    Functional electrical stimulation delivered early after injury to the proximal nerve stump has been proposed as a therapeutic approach for enhancing the speed and specificity of axonal regeneration following nerve injury. In this study, the injured oculomotor nerve was stimulated functionally by an implantable electrode. Electromyographic monitoring of the motor unit potential of the inferior oblique muscle was conducted for 12 weeks in two injury groups, one with and one without electric stimulation. The results revealed that, at 2, 4, 6, 8 weeks after functional electric stimulation of the injured oculomotor nerve, motor unit potentials significantly increased, such that amplitude was longer and spike duration gradually shortened. These findings indicate that the injured oculomotor nerve has the potential for regeneration and repair, but this ability is not sufficient for full functional recovery to occur. Importantly, the current results indicated that recovery and regeneration of the injured oculomotor nerve can be promoted with functional electrical stimulation.

  15. Use of cooperative game theory concepts for loss allocation in bilateral electricity markets

    International Nuclear Information System (INIS)

    The deregulation of electricity markets has resulted in changes in electricity pricing. Participants in a deregulated market require a fair and equitable pricing structure that reflects both the share of power produced and consumed in the network, as well as the cost of power loss caused by users. This paper focused on the allocation of losses using the cooperative game theory (CGT) where many transactions take place in a bilateral electricity market environment. A set of approaches documented in literature in the areas of application of CGT were first identified and their applicability to allocations of losses in bilateral electricity markets were then reviewed. The allocation methods can be classified into 3 broad categories, namely classical, new, and variants of nucleolus. The structure of the game and the concept of fairness behind it were the 2 points that were examined in detail in this study. The allocation concept of these methods was systematically analyzed and compared. Calculations were performed on a six-bus system sample and a standard IEEE 14-bus system. The variants of nucleolus were shown to be among the most plausible concepts. The power losses for each transaction were calculated using a power flow procedure. 16 refs., 4 tabs., 1 fig.

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

    Science.gov (United States)

    Zotz, T G G; Paula, J B de

    2015-11-01

    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<0.001) and between TG and CG (P<0.001). Qualitative histological analyses confirmed 100% HO in FG and CG, while in TG the HO was detected in 54.5% of the animals. The effects of the muscle contractions caused by FES increased HO, while anti-inflammatory effects of TENS reduced HO. PMID:26292223

  17. An Implantable Device for Electrical Nerve Stimulation

    OpenAIRE

    Moen, Lars Lyse

    2014-01-01

    Neural stimulation is currently subject to heavy research for the control of obesity using Vagus Nerve Stimulation (VNS). The available devices for such research is however developed for human use only, causing unnecessary complications when testing in smaller animals models due to the physical size of the device. A device for use in small animal models based on commercially available components would serve as a low-cost and more optimal solution to VNS research and similar disciplines.The de...

  18. Assessment of nerve morphology in nerve activation during electrical stimulation

    Science.gov (United States)

    Gomez-Tames, Jose; Yu, Wenwei

    2013-10-01

    The distance between nerve and stimulation electrode is fundamental for nerve activation in Transcutaneous Electrical Stimulation (TES). However, it is not clear the need to have an approximate representation of the morphology of peripheral nerves in simulation models and its influence in the nerve activation. In this work, depth and curvature of a nerve are investigated around the middle thigh. As preliminary result, the curvature of the nerve helps to reduce the simulation amplitude necessary for nerve activation from far field stimulation.

  19. 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...

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

    OpenAIRE

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

    2013-01-01

    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...

  1. 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...... 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...

  2. 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.

  3. Neuromechanism study of insect-machine interface: flight control by neural electrical stimulation.

    Science.gov (United States)

    Zhao, Huixia; Zheng, Nenggan; Ribi, Willi A; Zheng, Huoqing; Xue, Lei; Gong, Fan; Zheng, Xiaoxiang; Hu, Fuliang

    2014-01-01

    The insect-machine interface (IMI) is a novel approach developed for man-made air vehicles, which directly controls insect flight by either neuromuscular or neural stimulation. In our previous study of IMI, we induced flight initiation and cessation reproducibly in restrained honeybees (Apis mellifera L.) via electrical stimulation of the bilateral optic lobes. To explore the neuromechanism underlying IMI, we applied electrical stimulation to seven subregions of the honeybee brain with the aid of a new method for localizing brain regions. Results showed that the success rate for initiating honeybee flight decreased in the order: α-lobe (or β-lobe), ellipsoid body, lobula, medulla and antennal lobe. Based on a comparison with other neurobiological studies in honeybees, we propose that there is a cluster of descending neurons in the honeybee brain that transmits neural excitation from stimulated brain areas to the thoracic ganglia, leading to flight behavior. This neural circuit may involve the higher-order integration center, the primary visual processing center and the suboesophageal ganglion, which is also associated with a possible learning and memory pathway. By pharmacologically manipulating the electrically stimulated honeybee brain, we have shown that octopamine, rather than dopamine, serotonin and acetylcholine, plays a part in the circuit underlying electrically elicited honeybee flight. Our study presents a new brain stimulation protocol for the honeybee-machine interface and has solved one of the questions with regard to understanding which functional divisions of the insect brain participate in flight control. It will support further studies to uncover the involved neurons inside specific brain areas and to test the hypothesized involvement of a visual learning and memory pathway in IMI flight control. PMID:25409523

  4. Bilateral Lower Limb Amputations in a Nigerian Child Following High-Voltage Electrical Burns Injury: A Case Report

    OpenAIRE

    Dim, EM; Amanari, OC; Nottidge, TE; Inyang, UC; Nwashindi, A

    2013-01-01

    Abstract The human body conducts electricity very well. Direct contact with electric current can be lethal. The passage of electric current through the body is capable of producing a wide spectrum of injuries, including serious damage to the heart, brain, skin and muscles. Naked high-voltage electric cables negligently abandoned in residential, commercial and industrial areas are a recipe for disaster. This is a case report of a 5-year girl child who had bilateral lower limb gangrene followin...

  5. Nature of improvement in fatigue strength during electric stimulation

    International Nuclear Information System (INIS)

    The phase transformations taking place in stainless steel 08Kh18N10T under routine low-cycle fatigue loading as well as under conditions of electric stimulation are studied. The evolution pf phase composition and defect substructure is investigated using methods of electron diffraction microscopy. The electric stimulation is shown to result in a 30% increase of cycle number to fracture. It is revealed, that the suppression of martensitic γ-ε transformation is one of mechanisms of electric plastification on low cycle fatigue loading

  6. Dobutamine use for arrhythmia induction during electrical programmed heart stimulation

    International Nuclear Information System (INIS)

    isoproterenol is the traditionally used drug for incrementing arrhythmia induction when this induction is not achieved during electric programmed heart stimulation under basal conditions. Dobutamine is an adrenergic agent, chemical precursor of isoproterenol, which can be an alternative for inducing arrhythmia during electrical programmed heart stimulation (PES). Patients and methods: a retrospective comparative study of the experience with dobutamine for inducing arrhythmia during electrical programmed heart stimulation was performed. The following data were collected: number of studies, data about the patient (medical record, age, gender, and study indication) protocol of programmed electrical stimulation, basal and under dobutamine or isoproterenol, and result of the study. Isoproterenol was used in doses of 1 to 3 micrograms per minute until the basal heart rate was incremented at least in 25%. Dobutamine was used in doses of 10 to 40 micrograms per kg of body weight, until obtaining the same increment in the basal heart rate. Results: 1054 electrophysiological studies were evaluated. In 144 patients (group A) isoproterenol was used and in 140, dobutamine (group B). In A group the mean age was 39.2 ± 16.2 and 58.3% were females. In-group B, mean age was 41.9 ± 18.6 and 51% were females. The most frequent symptom was palpitation and the most commonly induced arrhythmia was AV nodal reentry tachycardia in both groups. The induction of arrhythmia during the electrical programmed heat stimulation under drugs was similar in-group A (isoproterenol) respect to group B (dobutamine). Conclusions: There were no statistical significant differences in the induction of arrhythmia during electrical programmed heart stimulation using dobutamine or isoproterenol. Dobutamine may be safe and may be successfully used as an alternative to isoproterenol for arrhythmia induction during electrical programmed stimulation

  7. Bladder emptying by intermittent electrical stimulation of the pudendal nerve

    Science.gov (United States)

    Boggs, Joseph W.; Wenzel, Brian J.; Gustafson, Kenneth J.; Grill, Warren M.

    2006-03-01

    Persons with a suprasacral spinal cord injury cannot empty their bladder voluntarily. Bladder emptying can be restored by intermittent electrical stimulation of the sacral nerve roots (SR) to cause bladder contraction. However, this therapy requires sensory nerve transection to prevent dyssynergic contraction of the external urethral sphincter (EUS). Stimulation of the compound pudendal nerve trunk (PN) activates spinal micturition circuitry, leading to a reflex bladder contraction without a reflex EUS contraction. The present study determined if PN stimulation could produce bladder emptying without nerve transection in cats anesthetized with α-chloralose. With all nerves intact, intermittent PN stimulation emptied the bladder (64 ± 14% of initial volume, n = 37 across six cats) more effectively than either distention-evoked micturition (40 ± 19%, p 0.10), indicating that PN stimulation was not limited by bladder-sphincter dyssynergia. Intermittent PN stimulation holds promise for restoring bladder emptying following spinal injury without requiring nerve transection.

  8. Improved bladder emptying in urinary retention by electrical stimulation of pudendal afferents

    Science.gov (United States)

    Peng, Chih-Wei; Chen, Jia-Jin Jason; Cheng, Chen-Li; Grill, Warren M.

    2008-06-01

    Urinary retention is the inability to empty the bladder completely, and may result from bladder hypocontractility, increases in outlet resistance or both. Chronic urinary retention can lead to several urological complications and is often refractory to pharmacologic, behavioral and surgical treatments. We sought to determine whether electrical stimulation of sensory fibers in the pudendal nerve could engage an augmenting reflex and thereby improve bladder emptying in an animal model of urinary retention. We measured the efficiency of bladder emptying with and without concomitant electrical stimulation of pudendal nerve afferents in urethane-anesthetized rats. Voiding efficiency (VE = voided volume/initial volume) was reduced from 72 ± 7% to 29 ± 7% following unilateral transection of the sensory branch of the pudendal nerve (UST) and from 70 ± 5% to 18 ± 4% following bilateral transection (BST). Unilateral electrical stimulation of the proximal transected sensory pudendal nerve during distention-evoked voiding contractions significantly improved VE. Low-intensity stimulation at frequencies of 1-50 Hz increased VE to 40-51% following UST and to 39-49% following BST, while high-intensity stimulation was ineffective at increasing VE. The increase in VE was mediated by increases in the duration of distention-evoked voiding bladder contractions, rather than increases in contraction amplitude. These results are consistent with an essential role for pudendal sensory feedback in efficient bladder emptying, and raise the possibility that electrical activation of pudendal nerve afferents may provide a new approach to restore efficient bladder emptying in persons with urinary retention.

  9. Why intra-epidermal electrical stimulation achieves stimulation of small fibres selectively: a simulation study.

    Science.gov (United States)

    Motogi, Jun; Sugiyama, Yukiya; Laakso, Ilkka; Hirata, Akimasa; Inui, Koji; Tamura, Manabu; Muragaki, Yoshihiro

    2016-06-21

    The in situ electric field in the peripheral nerve of the skin is investigated to discuss the selective stimulation of nerve fibres. Coaxial planar electrodes with and without intra-epidermal needle tip were considered as electrodes of a stimulator. From electromagnetic analysis, the tip depth of the intra-epidermal electrode should be larger than the thickness of the stratum corneum, the electrical conductivity of which is much lower than the remaining tissue. The effect of different radii of the outer ring electrode on the in situ electric field is marginal. The minimum threshold in situ electric field (rheobase) for free nerve endings is estimated to be 6.3 kV m(-1). The possible volume for electrostimulation, which can be obtained from the in situ electric field distribution, becomes deeper and narrower with increasing needle depth, suggesting that possible stimulation sites may be controlled by changing the needle depth. The injection current amplitude should be adjusted when changing the needle depth because the peak field strength also changes. This study shows that intra-epidermal electrical stimulation can achieve stimulation of small fibres selectively, because Aβ-, Aδ-, and C-fibre terminals are located at different depths in the skin. PMID:27223492

  10. Why intra-epidermal electrical stimulation achieves stimulation of small fibres selectively: a simulation study

    Science.gov (United States)

    Motogi, Jun; Sugiyama, Yukiya; Laakso, Ilkka; Hirata, Akimasa; Inui, Koji; Tamura, Manabu; Muragaki, Yoshihiro

    2016-06-01

    The in situ electric field in the peripheral nerve of the skin is investigated to discuss the selective stimulation of nerve fibres. Coaxial planar electrodes with and without intra-epidermal needle tip were considered as electrodes of a stimulator. From electromagnetic analysis, the tip depth of the intra-epidermal electrode should be larger than the thickness of the stratum corneum, the electrical conductivity of which is much lower than the remaining tissue. The effect of different radii of the outer ring electrode on the in situ electric field is marginal. The minimum threshold in situ electric field (rheobase) for free nerve endings is estimated to be 6.3 kV m‑1. The possible volume for electrostimulation, which can be obtained from the in situ electric field distribution, becomes deeper and narrower with increasing needle depth, suggesting that possible stimulation sites may be controlled by changing the needle depth. The injection current amplitude should be adjusted when changing the needle depth because the peak field strength also changes. This study shows that intra-epidermal electrical stimulation can achieve stimulation of small fibres selectively, because Aβ-, Aδ-, and C-fibre terminals are located at different depths in the skin.

  11. 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.

  12. 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.

  13. Serial 1H-MRS of thalamus during deep brain stimulation of bilateral globus pallidus internus for primary generalized dystonia

    International Nuclear Information System (INIS)

    The physiological mechanisms of deep brain stimulation (DBS) are not completely clear. Our understanding of them may be facilitated with the use of proton magnetic resonance spectroscopy (1H-MRS). Serial 1H-MRS of both thalami was performed during the course of DBS of bilateral globus pallidus internus in a patient with primary generalized dystonia. Two days after microelectrode implantation, a pulse frequency of 185 Hz was applied for stimulation. It resulted in relief of symptoms and a decrease of Burke-Fahn-Marsden dystonia rating scale (BFMDRS) scores, and was accompanied by a prominent increase of N-acetylaspartate (NAA)/choline-containing compounds (Cho) ratio, a mild increase of NAA/creatine (Cr) ratio, and a moderate decrease of Cho/Cr ratio. Two weeks later, for a search of the optimal stimulation mode, the pulse frequency was switched to 60 Hz, which resulted in clinical deterioration and significant increase of BFMDRS scores. At that time, all investigated 1H-MRS-detected metabolic parameters had nearly returned to the pretreatment levels. Use of serial 1H-MRS investigations of various brain structures during DBS in cases of movement disorders permits detailed evaluation of the treatment response, has a potential for its possible prediction, and may facilitate understanding of the physiological mechanisms of stimulation. (orig.)

  14. Economic substitutability of electrical brain stimulation, food, and water.

    OpenAIRE

    Green, L.; Rachlin, H

    1991-01-01

    Concurrent variable-ratio schedules of electrical brain stimulation, food, and water were paired in various combinations as reinforcement of rats' lever presses. Relative prices of the concurrent reinforcers were varied by changing the ratio of the response requirements on the two levers. Economic substitutability, measured by the sensitivity of response ratio to changes in relative price, was highest with brain stimulation reinforcement of presses on both levers and lowest with food reinforc...

  15. Study of Driving Fatigue Alleviation by Transcutaneous Acupoints Electrical Stimulations

    OpenAIRE

    Fuwang Wang; Hong Wang

    2014-01-01

    Driving fatigue is more likely to bring serious safety trouble to traffic. Therefore, accurately and rapidly detecting driving fatigue state and alleviating fatigue are particularly important. In the present work, the electrical stimulation method stimulating the Láogóng point (劳宫PC8) of human body is proposed, which is used to alleviate the mental fatigue of drivers. The wavelet packet decomposition (WPD) is used to extract θ, α, and β subbands of drivers' electroencephalogram (EEG) signals....

  16. 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.

  17. Skeletal scintigraphy for followup of fracture healing during electrical stimulation

    International Nuclear Information System (INIS)

    The influence of slowly pulsating bipolar sequences of rectangular pulses upon bone growth was investigated in animals. Control was achieved by analysis of bone mineral content, analysis of stability by use of the 3-point-bending-assay and by skeletal scintigraphy using sup(99m)Tc-diphosphonate. The results show up, that changes of mineralization are controlled by scintigraphy at an early time delivering reliable information concerning the efficiency of electrical stimulation. A case report demonstrates successful clinical use of the implantable electrical stimulator JES 2. (orig.)

  18. Effect of transcutaneous electric stimulation on the cardiac electrical activity in New Zealand white rabbits

    Directory of Open Access Journals (Sweden)

    Wang ZHANG

    2015-10-01

    Full Text Available Objective To study the effect of transcutaneous electric stimulation on the cardiac electrical activity in New Zealand white rabbits, in order to search a safety threshold for clinical electrical stimulation therapy, as to provide the theoretical basis for the design of in vitro pacemaker. Methods New Zealand white rabbits were randomly assigned into 17 groups (6 each. Rabbits in 16 experimental groups were given 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75 and 80V electrical stimulation, respectively, with the stimulating site designated at epigastric region. BL -420F biological function experimental system was employed to supply the power and acquire the ECG, with the output pulse electrical stimulation frequency set at 270 times/minute, and the stimulating wave as square wave. A control group was set, in which the stimulating voltage was set to 35V, the stimulant anode was located in the anterior chest area, and the cathode was on the skin surface of back corresponding to the site of the heart, and the rest was the same as in experimental groups. Results No stimulation rhythm was observed in rabbits of those experimental groups with voltage ≤35V, but all stimulation rhythm was observed in rabbits of control group. No arrhythmia occurred in rabbits of those experimental groups with voltage ≤30V, while the heart rate was slowed down after stimulation in rabbits of the experimental groups with voltage ≥45V stimulation. In rabbits receiving stimulation with voltage ≤35V there was no dystropy or light dystropy, but with no visible injury to the local tissues. No visible injury was observed in the rabbits undergoing stimulation with voltage ≤40V. Conclusion Pulse electric stimulation with voltage ≤35V in the epigastric region would not affect the cardiac electrical activity in rabbits, while stimulation with 35V will lead to all pacing rhythm of the heart without affecting the cardiac electrical activity in rabbits

  19. Electrical Stimulation of Microbial PCB Degradation in Sediment

    OpenAIRE

    Chun, Chan Lan; Payne, Rayford B; Sowers, Kevin R.; May, Harold D.

    2012-01-01

    Bioremediation of polychlorinated biphenyls (PCBs) has been precluded in part by the lack of a cost-effective method to stimulate microbial degradation in situ. A common limitation is the lack of an effective method of providing electron donors and acceptors to promote in situ PCB biodegradation. Application of an electric potential to soil/sediment could be an effective means of providing electron-donors/-acceptors to PCB dechlorinating and degrading microorganisms. In this study, electrical...

  20. Bilateral Repetitive Transcranial Magnetic Stimulation Combined with Intensive Swallowing Rehabilitation for Chronic Stroke Dysphagia: A Case Series Study

    Directory of Open Access Journals (Sweden)

    Ryo Momosaki

    2014-03-01

    Full Text Available The purpose of this study was to clarify the safety and feasibility of a 6-day protocol of bilateral repetitive transcranial magnetic stimulation (rTMS combined with intensive swallowing rehabilitation for chronic poststroke dysphagia. In-hospital treatment was provided to 4 poststroke patients (age at treatment: 56-80 years; interval between onset of stroke and treatment: 24-37 months with dysphagia. Over 6 consecutive days, each patient received 10 sessions of rTMS at 3 Hz applied to the pharyngeal motor cortex bilaterally, followed by 20 min of intensive swallowing rehabilitation exercise. The swallowing function was evaluated by the Penetration Aspiration Scale (PAS, Modified Mann Assessment of Swallowing Ability (MMASA, Functional Oral Intake Scale (FOIS, laryngeal elevation delay time (LEDT and Repetitive Saliva-Swallowing Test (RSST on admission and at discharge. All patients completed the 6-day treatment protocol and none showed any adverse reactions throughout the treatment. The combination treatment improved laryngeal elevation delay time in all patients. Our proposed protocol of rTMS plus swallowing rehabilitation exercise seems to be safe and feasible for chronic stroke dysphagia, although its efficacy needs to be confirmed in a large number of patients.

  1. Bio mathematical aspects of chronic cardiac electric stimulation

    International Nuclear Information System (INIS)

    In the framework a mathematical model of the electrode-tissue system new several concepts are introduced(global versus local threshold variables,critical region for electric stimulation,mechanical hysteresis amongst others) several well known facts are explained,and some guidelines for electrode design are derived

  2. Modulation of proprioceptive feedback during functional electrical stimulation

    DEFF Research Database (Denmark)

    Christensen, Mark Schram; Grey, Michael James

    2013-01-01

    Functional electrical stimulation (FES) is sometimes used as a therapeutic modality in motor rehabilitation to augment voluntary motor drive to effect movement that would otherwise not be possible through voluntary activation alone. Effective motor rehabilitation should require that the central n...

  3. Muscular urinary sphincter : electrically stimulated myoplasty for functional sphincter reconstruction

    NARCIS (Netherlands)

    Palacio, M M; Van Aalst, V C; Perez Abadia, G A; Stremel, R W; Werker, P M; Ren, X; Petty, G D; Heilman, S J; Van Savage, J G; Garcia Fernandez, A; Kon, M; Tobin, G R; Barker, J H

    1998-01-01

    PURPOSE: To reconstruct an electrically stimulated muscular urinary sphincter (MUS) using a tailored gracilis muscle free flap with intact nerve. MATERIALS AND METHODS: Unilateral surgically tailored gracilis muscle free flaps were transferred into the pelvis in eight dogs, leaving the obturator ner

  4. Electrical stimulation mapping of nouns and verbs in Broca's area.

    Science.gov (United States)

    Havas, Viktória; Gabarrós, Andreu; Juncadella, Montserrat; Rifa-Ros, Xavi; Plans, Gerard; Acebes, Juan José; de Diego Balaguer, Ruth; Rodríguez-Fornells, Antoni

    2015-01-01

    Electric stimulation mapping (ESM) is frequently used during brain surgery to localise higher cognitive functions to avoid post-chirurgical disabilities. Experiments with brain imaging techniques and neuropsychological studies showed differences in the cortical representation and processing of nouns and verbs. The goal of the present study was to investigate whether electric stimulation in specific sites in the frontal cortex disrupted noun and verb production selectively. We found that most of the stimulated areas showed disruption of both verbs and nouns at the inferior frontal gyrus. However, when selective effects were obtained, verbs were more prone to disruption than nouns with important individual differences. The overall results indicate that selective impairments can be observed at inferior and middle frontal regions and the action naming task seems to be more suitable to avoid post-chirurgical language disabilities, as it shows a greater sensitivity to disruption with ESM than the classical object naming task. PMID:25957505

  5. 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.

  6. Volume conductor model of transcutaneous electrical stimulation with kilohertz signals

    Science.gov (United States)

    Medina, Leonel E.; Grill, Warren M.

    2014-12-01

    Objective. Incorporating high-frequency components in transcutaneous electrical stimulation (TES) waveforms may make it possible to stimulate deeper nerve fibers since the impedance of tissue declines with increasing frequency. However, the mechanisms of high-frequency TES remain largely unexplored. We investigated the properties of TES with frequencies beyond those typically used in neural stimulation. Approach. We implemented a multilayer volume conductor model including dispersion and capacitive effects, coupled to a cable model of a nerve fiber. We simulated voltage- and current-controlled transcutaneous stimulation, and quantified the effects of frequency on the distribution of potentials and fiber excitation. We also quantified the effects of a novel transdermal amplitude modulated signal (TAMS) consisting of a non-zero offset sinusoidal carrier modulated by a square-pulse train. Main results. The model revealed that high-frequency signals generated larger potentials at depth than did low frequencies, but this did not translate into lower stimulation thresholds. Both TAMS and conventional rectangular pulses activated more superficial fibers in addition to the deeper, target fibers, and at no frequency did we observe an inversion of the strength-distance relationship. Current regulated stimulation was more strongly influenced by fiber depth, whereas voltage regulated stimulation was more strongly influenced by skin thickness. Finally, our model reproduced the threshold-frequency relationship of experimentally measured motor thresholds. Significance. The model may be used for prediction of motor thresholds in TES, and contributes to the understanding of high-frequency TES.

  7. Electrical Stimulation of Coleopteran Muscle for Initiating Flight

    Science.gov (United States)

    Choo, Hao Yu; Li, Yao; Cao, Feng; Sato, Hirotaka

    2016-01-01

    Some researchers have long been interested in reconstructing natural insects into steerable robots or vehicles. However, until recently, these so-called cyborg insects, biobots, or living machines existed only in science fiction. Owing to recent advances in nano/micro manufacturing, data processing, and anatomical and physiological biology, we can now stimulate living insects to induce user-desired motor actions and behaviors. To improve the practicality and applicability of airborne cyborg insects, a reliable and controllable flight initiation protocol is required. This study demonstrates an electrical stimulation protocol that initiates flight in a beetle (Mecynorrhina torquata, Coleoptera). A reliable stimulation protocol was determined by analyzing a pair of dorsal longitudinal muscles (DLMs), flight muscles that oscillate the wings. DLM stimulation has achieved with a high success rate (> 90%), rapid response time (< 1.0 s), and small variation (< 0.33 s; indicating little habituation). Notably, the stimulation of DLMs caused no crucial damage to the free flight ability. In contrast, stimulation of optic lobes, which was earlier demonstrated as a successful flight initiation protocol, destabilized the beetle in flight. Thus, DLM stimulation is a promising secure protocol for inducing flight in cyborg insects or biobots. PMID:27050093

  8. Electrical stimulation of the dorsolateral prefrontal cortex improves memory monitoring.

    Science.gov (United States)

    Chua, Elizabeth F; Ahmed, Rifat

    2016-05-01

    The ability to accurately monitor one's own memory is an important feature of normal memory function. Converging evidence from neuroimaging and lesion studies have implicated the dorsolateral prefrontal cortex (DLPFC) in memory monitoring. Here we used high definition transcranial direct stimulation (HD-tDCS), a non-invasive form of brain stimulation, to test whether the DLPFC has a causal role in memory monitoring, and the nature of that role. We used a metamemory monitoring task, in which participants first attempted to recall the answer to a general knowledge question, then gave a feeling-of-knowing (FOK) judgment, followed by a forced choice recognition task. When participants received DLPFC stimulation, their feeling-of-knowing judgments were better predictors of memory performance, i.e., they had better memory monitoring accuracy, compared to stimulation of a control site, the anterior temporal lobe (ATL). Effects of DLPFC stimulation were specific to monitoring accuracy, as there was no significant increase in memory performance, and if anything, there was poorer memory performance with DLPFC stimulation. Thus we have demonstrated a causal role for the DLPFC in memory monitoring, and showed that electrically stimulating the left DLPFC led people to more accurately monitor and judge their own memory. PMID:26970142

  9. Localization of cortical function using electrical stimulation and functional magnetic resonance imaging. Paradigms of neuronal stimulation

    International Nuclear Information System (INIS)

    In this review, localization of function is discussed with respect to distributed cortical areas involved in complex mental processing. After introducing the methodology of lesion studies, some results of studies using electrical cortical stimulation are presented. With respect to functional magnetic resonance imaging, results and problems from several experiments are reported, and further questions and perspectives regarding the two methods are outlined. (orig.)

  10. Direct-current electrical stimulation of tendon healing in vitro

    International Nuclear Information System (INIS)

    The intrinsic capacity of tendons to heal in response to injury has recently been demonstrated by many investigators. Electrical stimulation is often assumed to augment regeneration of various tissues. Using newly developed methods of whole-tendon culture, the authors examined the effect of direct-current electricity on healing in vitro. Deep flexor tendons of rabbits were excised, transected, repaired, and grown in an acellular culture medium for seven, 14, 21, or 42 days. Tendons through which a continuous 7-microAmp current was passed at the repair site were compared with nonstimulated controls. The incorporation of (14C)proline and its conversion to (14C)hydroxyproline was measured at seven days. The mean (14C)proline and (14C)hydroxyproline activities were 91% and 255% greater, respectively, in the stimulated group. The activity was also higher in the stimulated group, by 42 days. Histologic sections showed that intrinsic tenoblastic repair may be enhanced with electrical stimulation in vitro

  11. Remote electrical stimulation by means of implanted rectifiers.

    Science.gov (United States)

    Ivorra, Antoni

    2011-01-01

    Miniaturization of active implantable medical devices is currently compromised by the available means for electrically powering them. Most common energy supply techniques for implants--batteries and inductive couplers--comprise bulky parts which, in most cases, are significantly larger than the circuitry they feed. Here, for overcoming such miniaturization bottleneck in the case of implants for electrical stimulation, it is proposed to make those implants act as rectifiers of high frequency bursts supplied by remote electrodes. In this way, low frequency currents will be generated locally around the implant and these low frequency currents will perform stimulation of excitable tissues whereas the high frequency currents will cause only innocuous heating. The present study numerically demonstrates that low frequency currents capable of stimulation can be produced by a miniature device behaving as a diode when high frequency currents, neither capable of thermal damage nor of stimulation, flow through the tissue where the device is implanted. Moreover, experimental evidence is provided by an in vivo proof of concept model consisting of an anesthetized earthworm in which a commercial diode was implanted. With currently available microelectronic techniques, very thin stimulation capsules (diameter <500 µm) deliverable by injection are easily conceivable. PMID:21850274

  12. Electrical stimulation of primary neonatal rat ventricular cardiomyocytes using pacemakers.

    Science.gov (United States)

    Martherus, Ruben S R M; Zeijlemaker, Volkert A; Ayoubi, Torik A Y

    2010-01-01

    The study of gene regulation in cardiac myocytes requires a reliable in vitro model. However, monolayer cultures used for this purpose are typically not exposed to electrical stimulation, though this has been shown to strongly affect cardiomyocyte gene expression. Based on pacemakers for clinical use, we developed an easy-to-use portable system that allows the user to perform electro-stimulation of cardiomyocyte cultures in standard tissue incubators without the need for bulky equipment. In addition, we present a refined protocol for culturing high-purity cardiomyocyte cultures with excellent contractile properties for a wide variety of applications. PMID:20078430

  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...... likely 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...

  14. Comparative effects of unilateral and bilateral subthalamic nucleus deep brain stimulation on gait kinematics in Parkinson's disease: a randomized, blinded study.

    Science.gov (United States)

    Lizarraga, Karlo J; Jagid, Jonathan R; Luca, Corneliu C

    2016-08-01

    Gait dysfunction in Parkinson's disease (PD) does not always respond to bilateral subthalamic nucleus deep brain stimulation (STN-DBS). Since right hemisphere motor networks may be dominant for gait control, identical stimulation of asymmetric circuits could account for gait dysfunction. We compared the effects of bilateral and unilateral STN-DBS on gait kinematics in PD patients who developed gait impairment after STN-DBS. Twenty-two PD patients with >50 % improvement in motor scores, but dopamine-resistant gait dysfunction 6-12 months after bilateral STN-DBS were blindly tested off dopaminergic effects in four randomly assigned DBS conditions: bilateral, right-sided, left-sided and off stimulation. Motor scores (MDS-UPDRS III), gait scores (MDS-UPRDS 2.11-2.13 + 3.9-3.13), turning time (seconds), stride length (meters) and velocity (meters/second) were measured 1 h after DBS changes. Motor and gait scores significantly improved with bilateral versus unilateral STN-DBS. Stride length and velocity (0.95 ± 0.06, 0.84 ± 0.07) significantly improved with bilateral (1.09 ± 0.04, 0.95 ± 0.05), right-sided (1.06 ± 0.04, 0.92 ± 0.05) and left-sided stimulation (1.01 ± 0.05, 0.90 ± 0.05) (p programming of right versus left-sided STN-DBS is unclear, this approach could be considered in the management of treatment-resistant gait dysfunction in PD. PMID:27278062

  15. Neuromuscular Electrical Stimulation for Mobility Support of Elderly.

    Science.gov (United States)

    Mayr, Winfried

    2015-08-24

    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. Therefore the

  16. Modeling auditory-nerve responses to electrical stimulation

    DEFF Research Database (Denmark)

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

    2014-01-01

    Cochlear implants (CI) directly stimulate the auditory nerve (AN), bypassing the mechano-electricaltransduction in the inner ear. Trains of biphasic, charge-balanced pulses (anodic and cathodic) areused as stimuli to avoid damage of the tissue. The pulses of either polarity are capable of producing...... 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 to...... monophasic pulses. Strategies for improving the model performance with respect to correct AP timing are discussed. Eventually, a model that is able to account for correct spike timing in electrichearing will be useful for objective evaluation and improvement of CI stimulation strategies....

  17. 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...... high-quality head models from magnetic resonance images and their usage in subsequent field calculations based on the FEM. The pipeline starts by extracting the borders between skin, skull, cerebrospinal fluid, gray and white matter. The quality of the resulting surfaces is subsequently improved...... the successful usage of the pipeline in six subjects, including field calculations for transcranial magnetic stimulation and transcranial direct current stimulation. The quality of the head volume meshes is validated both in terms of capturing the underlying anatomy and of the well-shapedness of the mesh...

  18. Ultrasound guided, painful electrical stimulation of lumbar facet joint structures

    DEFF Research Database (Denmark)

    O'Neill, Søren; Graven-Nielsen, Thomas; Manniche, Claus; Arendt-Nielsen, Lars

    Quantitative sensory testing has indicated generalized muscle hyperalgesia in patients with chronic low back pain. The temporal development of such hyperalgesia is not well understood. The aim of the present study was to demonstrate whether generalized muscle hyperalgesia can develop within minutes...... of acute low back pain using a new experimental model of lumbar facet joint pain. Thirteen healthy volunteers were included and baseline pressure pain thresholds were assessed at eight separate sites, outside the area of evoked low back and referred pain. Using ultrasonography, two electrode needles...... were placed either side of a lumbar facet joint (right L3-4) and used to induce experimental low back pain for 10 min with continuous stimulation. Thresholds, stimulus-response relationships, distribution and quality of the electrically induced pain were recorded. Electrical facet joint stimulation...

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

    OpenAIRE

    2013-01-01

    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 fema...

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

    OpenAIRE

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

    2014-01-01

    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 ...

  1. Transcutaneous electrical nerve stimulation for cancer pain in adults.

    OpenAIRE

    Robb, Karen; Bennett, Michael I.; Johnson, Mark I.; Simpson, Karen H; Oxberry, Stephen G.

    2008-01-01

    Background Cancer-related pain is complex and multi-dimensional but the mainstay of cancer pain management has predominately used a biomedical approach. There is a need for non-pharmacological and innovative approaches. Transcutaneous Electric Nerve Stimulation (TENS) may have a role for a significant number of patients but the effectiveness of TENS is currently unknown. Objectives The aim of this systematic review was to determine the effectiveness of TENS for cancer-related pain in adults. ...

  2. Myogenic cell response to muscle contraction with short electrical stimulation

    OpenAIRE

    Tanaka, Shoji; Kawahara, Ei; Nakagawa, Takao

    2015-01-01

    [Purpose] The present study aimed to determine the effects of short muscle strength exercise on hepatocyte growth factor expression and satellite cell activation. [Subjects] The study included 72 2–12-week-old male Sprague-Dawley rats. [Methods] The rat plantaris muscle was contracted with a 5-min electrical stimulation of the sciatic nerve, and then, the mRNA expressions of hepatocyte growth factor and myogenic regulatory factors in the plantaris muscle were determined, and the phosphorylati...

  3. A clinical exercise system for paraplegics using functional electrical stimulation.

    Science.gov (United States)

    Bremner, L A; Sloan, K E; Day, R E; Scull, E R; Ackland, T

    1992-09-01

    A low cost clinical exercise system was developed for the spinal cord injured, based on a bicycle ergometer and electrical stimulation. A pilot project was conducted, using the system, to examine the effects of stimulation induced cycling in long term paraplegics. The project comprised 2 phases of exercise, a strengthening phase involving a 12 week programme of electrical stimulation to the quadriceps and hamstrings and a 12 week cycling phase. Physiological, morphological and biochemical parameters were measured for each subject, at the beginning of the programme and following each phase. Results showed that a programme of stimulation induced lower limb exercise increased the exercise tolerance of all patients, as determined by a progressive increase in exercise time, cycling rate and exercise load. The enhanced exercise tolerance was a result of increases in local muscle strength and endurance. Increases in thigh muscle area and joint range of motion were recorded and all incomplete subjects reported an improvement in functional capabilities and general wellbeing. PMID:1408342

  4. Response in primary somatosensory cortex following electrical stimulation of median nerve using fMRI

    International Nuclear Information System (INIS)

    To determine the location of the central sulcus is often clinically important, especially as presurgical information. To identify the central sulcus, we detected the post-central sulcus (primary somatosensory cortex, SI) using fMRI (functional magnetic resonance imaging). Ten healthy volunteers participated in this study. Using 3 Tesla MR imager (Medspec S300, Bruker), box-car design was applied following electrical median nerve stimulation. SPM99 (Welcome Department of Cognitive Neurology, London, UK) was used for the analysis and the statistical threshold was set at P<0.05. Contralateral response on SI was found in 8 out of 10 subjects. This response was divided into two patterns: group 1, SI activation only and group 2, both SI and primary motor cortex (MI) activation. Secondary somatosensory cortex (SII) activation was observed bilaterally in 5 subjects. Ipsilateral response was identified in 6 out of 8 subjects who showed contralateral response of SI. These fMRI findings were useful in defining the SI in the contralateral hemisphere following electrical stimulation of the median nerve, and led to the central sulcus, MI, or both. (author)

  5. Respiratory compromise: a rare complication of transcutaneous electrical nerve stimulation for angina pectoris.

    OpenAIRE

    Mann, C. J.

    1996-01-01

    Electrical stimulation of any muscle group may produce tetany. If the intercostal muscles are involved this may lead to respiratory embarrasment. A case is presented in which transcutaneous electrical nerve stimulation (TENS) treatment for angina pectoris resulted in respiratory arrest.

  6. New secure bilateral transaction determination and study of pattern under contingencies and UPFC in competitive hybrid electricity markets

    International Nuclear Information System (INIS)

    In the competitive electricity environment, the flexibility of power transactions is expected to drastically increase among the trading partners and can compromise the system security and reliability. These transactions are to be evaluated ahead of their scheduling in a day-ahead and hour-ahead market to avoid congestion and ensure their feasibility with respect to the system operating conditions. The security of the transactions has become essential in the new environment for better planning and management of competitive electricity markets. This paper proposes a new method of secure bilateral transaction determination using AC distribution factors based on the full Jacobian sensitivity and considering the impact of slack bus for pool and bilateral coordinated markets. The secure bilateral transactions have also been determined considering critical line outage contingencies cases. The bilateral transaction matrix pattern has also been determined in the presence of unified power flow controller (UPFC). The optimal location of UPFC has been determined using mixed integer non-linear programming approach. The proposed technique has been applied on IEEE 24-bus reliability test system (RTS). (author)

  7. Gender differences in current received during transcranial electrical stimulation

    Directory of Open Access Journals (Sweden)

    Michael eRussell

    2014-08-01

    Full Text Available Low current transcranial electrical stimulation is an effective but somewhat inconsistent tool for augmenting neuromodulation. In this study, we used 3D MRI guided electrical transcranial stimulation (GETS modeling to estimate the range of current intensities received at cortical brain tissues. Combined T1, T2, Proton Density MRIs from 24 adult subjects (12 male and 12 female were modeled with virtual electrodes placed at F3, F4, C3 and C4. Two sizes of electrodes 20 mm round and 50 x 45 mm square were examined at 0.5, 1 and 2 mA input currents. The intensity of current received was sampled in a one centimeter sphere placed at the cortex directly under each scalp electrode. There was a tenfold range in the current received by individuals. A large gender difference was observed with female subjects receiving significantly less current at targeted parietal cortex than male subjects when stimulated at identical current levels (P <0.05. Larger electrodes delivered somewhat larger amounts of current then the smaller ones (P <0.01. Electrodes in the frontal regions delivered less current than those in the parietal region (P<0.05. There were large individual differences in current levels the subjects received. Analysis of the cranial bone showed that the gender difference and the frontal parietal differences are due to differences in cranial bone. Males have more cancellous parietal bone and females more dense parietal bone (p<0.01. These differences should be considered when planning transcranial electrical stimulation studies and call into question earlier reports of gender differences due to hormonal influences.

  8. Effects of electrical stimulated hypothalamuic paraventricular nucleus ongastric ischemia-reperfusion injury in rats

    Institute of Scientific and Technical Information of China (English)

    Jian Fu Zhang; Yong Mei Zhang; Chang Dong Yan

    2000-01-01

    AIM To investigate the effect and regulation of electrical stimulation on the paraventricular nucleus (PVN)of hypothalamus using rat gastric ischemia-reperfusion injury (I-RI)induced ulcer model.METHODS Adult male Sprague-Dawley rats weighing 150 g-250 g were used. The surgically prepared ratswere kept fasting for 24 h, but allowed free access to water. They were then anesthetized with urathane(1 g/kg), the celiac artery was clamped with a small clip (holding force 145 g) for 30min, reperfusion wasestablished by removal of the clamp, 60min after reperfusion, the rats were killed and their stomachs wereremoved and perfused intragastrically with 100 mL/L formalin for 30min, and the ulcer index was scoredaccording to Guth et al. The PVN was obtained according to atlas of Paxinos and Watson. The electrodesand cannula were inserted into the PVN for the electrical stimulation, electrical injury and PVN injection,RESULTS In control group (30min ischemia and 60ain reperfusion only), ulcer index was 184.70±60.80(n = 8); in electrical stimulations of PVN (0.2mA, 0.4mA and 0.6mA) + I-RI group, ulcer indexes were102.40±20.39, 85.37±39.76 and 45.00±19.04 (n =8) respectively. Compared with the control groupthere was significant difference ( P < 0.01) in a dose-dependent manner. In electrical lesion of bilateral PVN+ I-RI group, ulcer index was greatly increased (230.00±47.30, n = 8). Microinjection of 3% L-glutamate0.5μL into PVN could produce similar effect to that of PVN stimulation (ulcer index 75.14±37.18, n = 8).A further study indicated that the MDA, pepsin activity and gastric acidity were reduced by PVN stimulationbut no obvious changes of gastric juice volume, total acid output and gastric mucus barrier were observed.CONCLUSION The PVN is one of the specific CNS areas capable of protecting the gastric ischemic-reperfusion injury in rats, and related to decreased MPA, pepsin activity, gastric acidity, while gastric juicevolume, total acid output and gastric

  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. PMID:19481236

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

    International Nuclear Information System (INIS)

    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.

  11. 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.

  12. Preoperative transcutaneous electrical nerve stimulation for localizing superficial nerve paths.

    Science.gov (United States)

    Natori, Yuhei; Yoshizawa, Hidekazu; Mizuno, Hiroshi; Hayashi, Ayato

    2015-12-01

    During surgery, peripheral nerves are often seen to follow unpredictable paths because of previous surgeries and/or compression caused by a tumor. Iatrogenic nerve injury is a serious complication that must be avoided, and preoperative evaluation of nerve paths is important for preventing it. In this study, transcutaneous electrical nerve stimulation (TENS) was used for an in-depth analysis of peripheral nerve paths. This study included 27 patients who underwent the TENS procedure to evaluate the peripheral nerve path (17 males and 10 females; mean age: 59.9 years, range: 18-83 years) of each patient preoperatively. An electrode pen coupled to an electrical nerve stimulator was used for superficial nerve mapping. The TENS procedure was performed on patients' major peripheral nerves that passed close to the surgical field of tumor resection or trauma surgery, and intraoperative damage to those nerves was apprehensive. The paths of the target nerve were detected in most patients preoperatively. The nerve paths of 26 patients were precisely under the markings drawn preoperatively. The nerve path of one patient substantially differed from the preoperative markings with numbness at the surgical region. During surgery, the nerve paths could be accurately mapped preoperatively using the TENS procedure as confirmed by direct visualization of the nerve. This stimulation device is easy to use and offers highly accurate mapping of nerves for surgical planning without major complications. The authors conclude that TENS is a useful tool for noninvasive nerve localization and makes tumor resection a safe and smooth procedure. PMID:26420473

  13. PI controller scheme for charge balance in implantable electrical stimulators

    Indian Academy of Sciences (India)

    C Rathna

    2016-01-01

    Electrical stimulation has been used in a wide variety of medical implant applications. In all of these applications, due to safety concerns, maintaining charge balance becomes a critically important issue that needs to be addressed at the design stage. It is important that charge balancing schemes be robust to circuit (process) and load impedance variations, and at the same time must also lend themselves to miniaturization. In this communication, simulation studies on the effectiveness of using Proportional Integral (P-I) control schemes for managing charge balance in electrical stimulation are presented. The adaptation of the P-I control scheme to implant circuits leads to two possible circuit realizations in the analog domain. The governing equations for these realizations are approximated to simple linear equations. Considering typical circuit and tissue parameter values and their expected uncertainties, Matlab as well as circuit simulations have been carried out. Simulation results presented indicate that the tissue voltages settle to well below 20% of the safe levels and within about 20 stimulations cycles, thus confirming the validity and robustness of the proposed schemes.

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

    OpenAIRE

    Beckwée, David; Bautmans, Ivan; Swinnen, Eva; Vermet, Yorick; Lefeber, Nina; Lievens, Pierre; Vaes, Peter

    2014-01-01

    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...

  15. Modulating Human Auditory Processing by Transcranial Electrical Stimulation.

    Science.gov (United States)

    Heimrath, Kai; Fiene, Marina; Rufener, Katharina S; Zaehle, Tino

    2016-01-01

    Transcranial electrical stimulation (tES) has become a valuable research tool for the investigation of neurophysiological processes underlying human action and cognition. In recent years, striking evidence for the neuromodulatory effects of transcranial direct current stimulation, transcranial alternating current stimulation, and transcranial random noise stimulation has emerged. While the wealth of knowledge has been gained about tES in the motor domain and, to a lesser extent, about its ability to modulate human cognition, surprisingly little is known about its impact on perceptual processing, particularly in the auditory domain. Moreover, while only a few studies systematically investigated the impact of auditory tES, it has already been applied in a large number of clinical trials, leading to a remarkable imbalance between basic and clinical research on auditory tES. Here, we review the state of the art of tES application in the auditory domain focussing on the impact of neuromodulation on acoustic perception and its potential for clinical application in the treatment of auditory related disorders. PMID:27013969

  16. Pattern of secure bilateral transactions ensuring power economic dispatch in hybrid electricity markets

    International Nuclear Information System (INIS)

    This paper proposes a new method for secure bilateral transactions determination ensuring economic power dispatch of the generators using new AC distribution factors for pool and bilateral coordinated markets. The new optimization problem considers simultaneous minimization of deviations from scheduled transactions and fuel cost of the generators in the network. The fuel cost has been obtained for hybrid market model and impact of different percentage of bilateral demand on fuel cost, generation share, and pattern of transactions has also been determined. The impact of optimally located unified power flow controller (UPFC) on the bilateral transactions, fuel cost and generation pattern has also been studied. The results have also been obtained for pool market model. The proposed technique has been applied on IEEE 24-bus reliability test system (RTS). (author)

  17. 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 < 0.001). There were no unique complications associated with the RMNS treatment. The current study, although with some limitations, showed that RMNS may serve as an easy, effective, and noninvasive technique to promote the recovery of traumatic coma in the early phase. PMID:25664378

  18. Neuronal excitability level transition induced by electrical stimulation

    Science.gov (United States)

    Florence, G.; Kurths, J.; Machado, B. S.; Fonoff, E. T.; Cerdeira, H. A.; Teixeira, M. J.; Sameshima, K.

    2014-12-01

    In experimental studies, electrical stimulation (ES) has been applied to induce neuronal activity or to disrupt pathological patterns. Nevertheless, the underlying mechanisms of these activity pattern transitions are not clear. To study these phenomena, we simulated a model of the hippocampal region CA1. The computational simulations using different amplitude levels and duration of ES revealed three states of neuronal excitability: burst-firing mode, depolarization block and spreading depression wave. We used the bifurcation theory to analyse the interference of ES in the cellular excitability and the neuronal dynamics. Understanding this process would help to improve the ES techniques to control some neurological disorders.

  19. Functional electrical stimulation for incomplete spinal cord injury

    OpenAIRE

    Fazio, Christina

    2014-01-01

    This case report describes the early use of functional electrical stimulation on an individual with an incomplete spinal cord injury to assist with motor recovery and a return to ambulation. A 32-year-old woman sustained a C7 burst fracture after a fall, requiring anterior cervical fixation from C6 to T1 prior to transfer to acute rehabilitation. She presented as a C8 AIS B spinal cord injury, meaning she had some sensory function spared below the level of injury but not motor function. At di...

  20. Stroke Rehabilitation using Learning Control Mediated by Electrical Stimulation

    OpenAIRE

    Meadmore, Katie L.; Hughes, Anne-Marie; Cai, Zhonglun; Tong, Daisy; Freeman, Christopher; Burridge, Jane; Rogers, Eric

    2010-01-01

    Many people have problems with using their arm after a stroke, which can affect their ability to perform activities like reaching out to pick an object up. Over the last few years new technologies which use robots and electrical stimulation (ES) of muscles have been used to help with these problems. We have developed a new system which employs both of these technologies in conjunction with a technique called “Iterative Learning Control” (ILC) to help people recover movement in their arm. The ...

  1. 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.

  2. Chronological Changes of C-Reactive Protein Levels Following Uncomplicated, Two-Staged, Bilateral Deep Brain Stimulation

    Science.gov (United States)

    Kim, Jae-hun; Ha, Sang-woo; Choi, Jin-gyu

    2015-01-01

    Objective The occurrence of acute cerebral infection following deep brain stimulation (DBS) is currently being reported with elevation of C-reactive protein (CRP) level. The aim of the present study was to establish normal range of the magnitude and time-course of CRP increases following routine DBS procedures in the absence of clinical and laboratory signs of infection. Methods A retrospective evaluation of serial changes of plasma CRP levels in 46 patients undergoing bilateral, two-staged DBS was performed. Because DBS was performed as a two-staged procedure involving; implantation of lead and internal pulse generator (IPG), CRP was measured preoperatively and postoperatively every 2 days until normalization of CRP (post-lead implantation day 2 and 4, post-IPG implantation day 2, 4, and 6). Results Compared with preoperative CRP levels (0.12±0.17 mg/dL, n=46), mean CRP levels were significantly elevated after lead insertion day 2 and 4 (1.68±1.83 mg/dL, n=46 and 0.76±0.38 mg/dL, n=16, respectively, p0.05). Mean CRP levels after IPG implantation were significantly higher in patients whose IPGs were implanted at post-lead day 3 than those at post-lead day 5-6 (3.99±2.80 mg/dL, n=30, and 2.31±1.56 mg/dL, n=16, respectively, p0.05). Conclusion The mean postoperative CRP levels were highest on post-IPG insertion day 2 and decreased rapidly, returning to the normal range on post-IPG implantation day 6. The duration of post-lead implantation period influenced the magnitude of CRP elevation at post-IPG insertion day 2. Information about the normal response of CRP following DBS could help to avoid unnecessary diagnostic and therapeutic efforts. PMID:26587192

  3. Temporal lobe cortical electrical stimulation during the encoding and retrieval phase reduces false memories.

    Directory of Open Access Journals (Sweden)

    Paulo S Boggio

    Full Text Available A recent study found that false memories were reduced by 36% when low frequency repetitive transcranial magnetic stimulation (rTMS was applied to the left anterior temporal lobe after the encoding (study phase. Here we were interested in the consequences on a false memory task of brain stimulation throughout the encoding and retrieval task phases. We used transcranial direct current stimulation (tDCS because it has been shown to be a useful tool to enhance cognition. Specifically, we examined whether tDCS can induce changes in a task assessing false memories. Based on our preliminary results, three conditions of stimulation were chosen: anodal left/cathodal right anterior temporal lobe (ATL stimulation ("bilateral stimulation"; anodal left ATL stimulation (with a large contralateral cathodal electrode--referred as "unilateral stimulation" and sham stimulation. Our results showed that false memories were reduced significantly after the two active conditions (unilateral and bilateral stimulation as compared with sham stimulation. There were no significant changes in veridical memories. Our findings show that false memories are reduced by 73% when anodal tDCS is applied to the anterior temporal lobes throughout the encoding and retrieval stages, suggesting a possible strategy for improving certain aspects of learning.

  4. Electrical stimulation to optimize cardioprotective exosomes from cardiac stem cells.

    Science.gov (United States)

    Campbell, C R; Berman, A E; Weintraub, N L; Tang, Y L

    2016-03-01

    Injured or ischemic cardiac tissue has limited intrinsic capacity for regeneration. While stem cell transplantation is a promising approach to stimulating cardiac repair, its success in humans has thus far been limited. Harnessing the therapeutic benefits of stem cells requires a better understanding of their mechanisms of action and methods to optimize their function. Cardiac stem cells (CSC) represent a particularly effective cellular source for cardiac repair, and pre-conditioning CSC with electrical stimulation (EleS) was demonstrated to further enhance their function, although the mechanisms are unknown. Recent studies suggest that transplanted stem cells primarily exert their effects through communicating with endogenous tissues via the release of exosomes containing cardioprotective molecules such as miRNAs, which upon uptake by recipient cells may stimulate survival, proliferation, and angiogenesis. Exosomes are also effective therapeutic agents in isolation and may provide a feasible alternative to stem cell transplantation. We hypothesize that EleS enhances CSC-mediated cardiac repair through its beneficial effects on production of cardioprotective exosomes. Moreover, we hypothesize that the beneficial effects of biventricular pacing in patients with heart failure may in part result from EleS-induced preconditioning of endogenous CSC to promote cardiac repair. With future research, our hypothesis may provide applications to optimize stem cell therapy and augment current pacing protocols, which may significantly advance the treatment of patients with heart disease. PMID:26880625

  5. A combined pool/bilateral dispatch model for electricity markets with security constraints Un modelo combinado de despacho pool/bilateral para mercados

    Directory of Open Access Journals (Sweden)

    Jesús María López–Lezama

    2011-06-01

    Full Text Available The secure operation of the electric power system is a challenging task for the system operator which is responsible of its coordination, control and monitoring. In most power systems security is typically handled on a multi–stateapproach. In which case, security criteria are incorporated by means of additional constraints, modifying the initial dispatch calculation. In this papera generation dispatch model for competitive energy markets considering security constraints is presented. The proposed approach combines the generationdispatch related to pool and bilateral markets with coupled post–contingency optimal power flows into a single optimal dispatch model, avoiding economic inefficiencies that appear in conventional multi–stage dispatch approaches.The proposed model is linear, and as such, it is based on a DC model of the network. A 6–bus didactic system and the IEEE RTS–24 bus test systemare used in order to show the operation and effectiveness of the proposed approach and to compare it with the basic pool/bilateral dispatch with no security constraints. Results show that the inclusion of security constraints leadto a higher dispatch cost. Furthermore, it was found that the enforcement offirmed bilateral contracts might lead to system congestion.La operacíon segura del sistema de potencia es una tarea difícil para el operador del sistema, el cual es responsable por la coordinación, control y monitoreo de este. En la mayoría de los sistemas de potencia, la seguridad es manejada mediante una metodología multi–etapa. En este caso, los criterios de seguridad son incorporados mediante restricciones adicionales que modifican el cálculo de despacho inicial. En este artículo se presenta un modelo de despacho de generación para mercados eléctricos competitivos considerando restricciones de seguridad. La metodología propuesta combina el despacho de generación de mercados pool y contratos bilaterales con flujos de potencia

  6. Effectiveness of electrical stimulation in idiopathic Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Ebrahim NKC

    2015-04-01

    Full Text Available Background: Parkinson's disease is one of the most disabling chronic neurologic diseases and leads to a significant loss of quality of life. Electrical stimulation activate nerves innervating extremities affected by paralysis resulting from Spinal Cord Injury (SCI, head injury, stroke and hence is primarily used to restore function in people with disabilities. Methods: The study was performed after the institutional ethical clearance and informed consent from all the participants. The parameters assessed were time taken to complete 20 M walk with turn round, distance covered in the first 3 minutes of walking, gait dynamics like stride length, step length and cadence and number of falls with the help of video tape recorder, stop watch and measuring tape. Results: We observed a non-significant reduction (P = 0.471 of UPDRS, mean score of PDQ-39 was declined non-significantly (P = 0.36, time taken to complete 20 meters walk with turn was declined significantly (P = 0.017, The distances walked in 3 minutes by the patients were increased significantly (P = 0.000, number of steps during 20 meter walk was recorded and was found to be declined significantly (P = 0.088, stride length of the patients were increased significantly (P = 0.000, step length of the patients was increased significantly (P = 0.000, average number of falls reduced significantly (P = 0.00 during the stimulation period from week 0 to week 8. Conclusion: This study demonstrated the superior efficacy of electrical stimulation over best medical management in patients with advanced Parkinson's disease. [Int J Res Med Sci 2015; 3(4.000: 963-967

  7. 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

  8. High-Voltage Pulsed Current Electrical Stimulation in Wound Treatment.

    Science.gov (United States)

    Polak, Anna; Franek, Andrzej; Taradaj, Jakub

    2014-02-01

    Significance: A range of studies point to the efficacy of electrical stimulation (ES) in wound treatment, but the methodology of its application has not been determined to date. This article provides a critical review of the results of clinical trials published by researchers using high-voltage pulsed current (HVPC) to treat chronic wounds. In describing the methodology of the trials, the article gives special attention to electric stimulus parameters, the frequency of procedures and total treatment duration. Recent Advances: HVPC is a monophasic pulsed electric current that consists of double-peaked impulses (5-200 μs), at very high peak-current amplitude (2-2.5 A), and high voltage (up to 500 V), at a frequency of 1-125 pulses per second. HVPC can activate "skin battery" and cellular galvanotaxis, and improves blood flow and capillary density. Critical Issues: HVPC efficacy was evaluated in conservatively treated patients with diabetic foot, venous leg and pressure ulcers (PUs), and in some patients with surgically treated venous insufficiency. Future Directions: The efficacy of HVPC as one of several biophysical energies promoting venous leg ulcer (VLU) and PU healing has been confirmed. Additional studies are needed to investigate its effect on the healing of other types of soft tissue defects. Other areas that require more research include the identification of the therapeutic effect of HVPC on infected wounds, the determination of the efficacy of cathodal versus anodal stimulation, and the minimal daily/weekly duration of HVPC required to ensure optimal promotion of wound healing. PMID:24761351

  9. Interferential electrical stimulation improves peripheral vasodilatation in healthy individuals

    Directory of Open Access Journals (Sweden)

    Francisco V. Santos

    2013-06-01

    Full Text Available BACKGROUND: Interferential electrical stimulation (IES, which may be linked to greater penetration of deep tissue, may restore blood flow by sympathetic nervous modulation; however, studies have found no association between the frequency and duration of the application and blood flow. We hypothesized that 30 min of IES applied to the ganglion stellate region might improve blood flow redistribution. OBJECTIVES: The purpose of this study was to determine the effect of IES on metaboreflex activation in healthy individuals. METHOD: Interferential electrical stimulation or a placebo stimulus (same protocol without electrical output was applied to the stellate ganglion region in eleven healthy subjects (age 25±1.3 years prior to exercise. Mean blood pressure (MBP, heart rate (HR, calf blood flow (CBF and calf vascular resistance (CVR were measured throughout exercise protocols (submaximal static handgrip exercise and with recovery periods with or without postexercise circulatory occlusion (PECO+ and PECO -, respectively. Muscle metaboreflex control of calf vascular resistance was estimated by subtracting the area under the curve when circulation was occluded from the area under the curve from the AUC without circulatory occlusion. RESULTS: At peak exercise, increases in mean blood pressure were attenuated by IES (p<0.05, and the effect persisted under both the PECO+ and PECO- treatments. IES promoted higher CBF and lower CVR during exercise and recovery. Likewise, IES induced a reduction in the estimated muscle metaboreflex control (placebo, 21±5 units vs. IES, 6±3, p<0.01. CONCLUSION: Acute application of IES prior to exercise attenuates the increase in blood pressure and vasoconstriction during exercise and metaboreflex activation in healthy subjects.

  10. Organ of Corti Micromechanics with Local Electrical Stimulation

    Science.gov (United States)

    Chen, Fangyi; Zheng, Jiefu; Choudhury, Niloy; Jaques, Steve; Nuttall, Alfred L.

    2009-02-01

    Optical low coherence interferometry is able to both image and measure the vibration of the cellular and non-cellular structures of the organ of Corti in vivo. In this study we applied an electric current to the basal turn from a pair of electrodes, one in scala tympani and the other in scala vestibuli, at the location corresponding to ~17 kHz when interferometry measurements were made. The coherence gate of the interferometer was positioned 1) at the basilar membrane (BM) near the radial location of the outer hair cells (OHCs) (approximately 1/2 the width of the BM) and 2) at the reticular lamina (RL) where the OHCs are located. We confirmed that electrical stimulation with a frequency sweep (12 kHz -25 kHz) caused a mechanical BM displacement with a peak and a traveling wave-like phase delay as we reported previously using laser Doppler velocimetry and reflective beads on the BM. Reflective beads were not used in the current study. The vibration of the RL had little or no phase delay that would characterize a traveling wave. These data suggest a very high compliance system for the electrically activated cellular structure of the organ.

  11. Characterization of pulse amplitude and pulse rate modulation for a human vestibular implant during acute electrical stimulation

    Science.gov (United States)

    Nguyen, T. A. K.; DiGiovanna, J.; Cavuscens, S.; Ranieri, M.; Guinand, N.; van de Berg, R.; Carpaneto, J.; Kingma, H.; Guyot, J.-P.; Micera, S.; Perez Fornos, A.

    2016-08-01

    Objective. The vestibular system provides essential information about balance and spatial orientation via the brain to other sensory and motor systems. Bilateral vestibular loss significantly reduces quality of life, but vestibular implants (VIs) have demonstrated potential to restore lost function. However, optimal electrical stimulation strategies have not yet been identified in patients. In this study, we compared the two most common strategies, pulse amplitude modulation (PAM) and pulse rate modulation (PRM), in patients. Approach. Four subjects with a modified cochlear implant including electrodes targeting the peripheral vestibular nerve branches were tested. Charge-equivalent PAM and PRM were applied after adaptation to baseline stimulation. Vestibulo-ocular reflex eye movement responses were recorded to evaluate stimulation efficacy during acute clinical testing sessions. Main results. PAM evoked larger amplitude eye movement responses than PRM. Eye movement response axes for lateral canal stimulation were marginally better aligned with PRM than with PAM. A neural network model was developed for the tested stimulation strategies to provide insights on possible neural mechanisms. This model suggested that PAM would consistently cause a larger ensemble firing rate of neurons and thus larger responses than PRM. Significance. Due to the larger magnitude of eye movement responses, our findings strongly suggest PAM as the preferred strategy for initial VI modulation.

  12. 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. PMID:27233590

  13. 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...

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

    Science.gov (United States)

    Opitz, Alexander; Falchier, Arnaud; Yan, Chao-Gan; Yeagle, Erin M; Linn, Gary S; Megevand, Pierre; Thielscher, Axel; Deborah A, Ross; Milham, Michael P; Mehta, Ashesh D; Schroeder, Charles E

    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 mV/mm. Our results provide crucial information of the underlying biophysics in TES applications in humans and the optimization and design of TES stimulation protocols. In addition, our findings have broad implications concerning electric field propagation in non-invasive recording techniques such as EEG/MEG. PMID:27535462

  16. Different Movement of Hyolaryngeal Structures by Various Application of Electrical Stimulation in Normal Individuals

    OpenAIRE

    Kim, Sae Hyun; Oh, Byung-Mo; Han, Tae Ryun; Jeong, Ho Joong; Sim, Young Joo

    2015-01-01

    Objective To identify the differences in the movement of the hyoid bone and the vocal cord with and without electrical stimulation in normal subjects. Methods Two-dimensional motion analysis using a videofluoroscopic swallowing study with and without electrical stimulation was performed. Surface electrical stimulation was applied during swallowing using electrodes placed at three different locations on each subject. All subjects were analyzed three times using the following electrode placemen...

  17. Charge-balanced biphasic electrical stimulation inhibits neurite extension of spiral ganglion neurons.

    Science.gov (United States)

    Shen, Na; Liang, Qiong; Liu, Yuehong; Lai, Bin; Li, Wen; Wang, Zhengmin; Li, Shufeng

    2016-06-15

    Intracochlear application of exogenous or transgenic neurotrophins, such as neurotrophin-3 (NT-3) and brain derived neurotrophic factor (BDNF), could promote the resprouting of spiral ganglion neuron (SGN) neurites in deafened animals. These resprouting neurites might reduce the gap between cochlear implant electrodes and their targeting SGNs, allowing for an improvement of spatial resolution of electrical stimulation. This study is to investigate the impact of electrical stimulation employed in CI on the extension of resprouting SGN neurites. We established an in vitro model including the devices delivering charge-balanced biphasic electrical stimulation, and spiral ganglion (SG) dissociated culture treated with BDNF and NT-3. After electrical stimulation with varying durations and intensities, we quantified neurite lengths and Schwann cell densities in SG cultures. Stimulations that were greater than 50μA or longer than 8h significantly decreased SG neurite length. Schwann cell density under 100μA electrical stimulation for 48h was significantly lower compared to that in non-stimulated group. These electrical stimulation-induced decreases of neurite extension and Schwann cell density were attenuated by various types of voltage-dependent calcium channel (VDCC) blockers, or completely prevented by their combination, cadmium or calcium-free medium. Our study suggested that charge-balanced biphasic electrical stimulation inhibited the extension of resprouting SGN neurites and decreased Schwann cell density in vitro. Calcium influx through multiple types of VDCCs was involved in the electrical stimulation-induced inhibition. PMID:27163199

  18. Autonomic Modulation by Electrical Stimulation of the Parasympathetic Nervous System: An Emerging Intervention for Cardiovascular Diseases.

    Science.gov (United States)

    He, Bo; Lu, Zhibing; He, Wenbo; Huang, Bing; Jiang, Hong

    2016-06-01

    The cardiac autonomic nervous system has been known to play an important role in the development and progression of cardiovascular diseases. Autonomic modulation by electrical stimulation of the parasympathetic nervous system, which increases the parasympathetic activity and suppresses the sympathetic activity, is emerging as a therapeutic strategy for the treatment of cardiovascular diseases. Here, we review the recent literature on autonomic modulation by electrical stimulation of the parasympathetic nervous system, including vagus nerve stimulation, transcutaneous auricular vagal stimulation, spinal cord stimulation, and ganglionated plexi stimulation, in the treatment of heart failure, atrial fibrillation, and ventricular arrhythmias. PMID:26914959

  19. Numerical simulation of electrically stimulated osteogenesis in dental implants.

    Science.gov (United States)

    Vanegas-Acosta, J C; Garzón-Alvarado, D A; Lancellotti, V

    2014-04-01

    Cell behavior and tissue formation are influenced by a static electric field (EF). Several protocols for EF exposure are aimed at increasing the rate of tissue recovery and reducing the healing times in wounds. However, the underlying mechanisms of the EF action on cells and tissues are still a matter of research. In this work we introduce a mathematical model for electrically stimulated osteogenesis at the bone-dental implant interface. The model describes the influence of the EF in the most critical biological processes leading to bone formation at the bone-dental implant interface. The numerical solution is able to reproduce the distribution of spatial-temporal patterns describing the influence of EF during blood clotting, osteogenic cell migration, granulation tissue formation, displacements of the fibrillar matrix, and formation of new bone. In addition, the model describes the EF-mediated cell behavior and tissue formation which lead to an increased osteogenesis in both smooth and rough implant surfaces. Since numerical results compare favorably with experimental evidence, the model can be used to predict the outcome of using electrostimulation in other types of wounds and tissues. PMID:24413341

  20. Validating computationally predicted TMS stimulation areas using direct electrical stimulation in patients with brain tumors near precentral regions

    Directory of Open Access Journals (Sweden)

    Alexander Opitz

    2014-01-01

    Full Text Available The spatial extent of transcranial magnetic stimulation (TMS is of paramount interest for all studies employing this method. It is generally assumed that the induced electric field is the crucial parameter to determine which cortical regions are excited. While it is difficult to directly measure the electric field, one usually relies on computational models to estimate the electric field distribution. Direct electrical stimulation (DES is a local brain stimulation method generally considered the gold standard to map structure–function relationships in the brain. Its application is typically limited to patients undergoing brain surgery. In this study we compare the computationally predicted stimulation area in TMS with the DES area in six patients with tumors near precentral regions. We combine a motor evoked potential (MEP mapping experiment for both TMS and DES with realistic individual finite element method (FEM simulations of the electric field distribution during TMS and DES. On average, stimulation areas in TMS and DES show an overlap of up to 80%, thus validating our computational physiology approach to estimate TMS excitation volumes. Our results can help in understanding the spatial spread of TMS effects and in optimizing stimulation protocols to more specifically target certain cortical regions based on computational modeling.

  1. Alterations in body composition and spasticity following subtetanic neuromuscular electrical stimulation training in spinal cord injury

    Directory of Open Access Journals (Sweden)

    Louis Crowe, MB, BCh, BAO

    2013-04-01

    Full Text Available The objective of this prospective cohort study was to investigate alterations in body composition variables and spasticity following subtetanic neuromuscular electrical stimulation (NMES training in an adult population with spinal cord injury (SCI. Fourteen sedentary adults with SCI (thoracic [T]4–T11; American Spinal Injury Association Impairment Scale A/B; time since injury: 10.17 +/– 11.17 yr were recruited from the National SCI database. Four adhesive electrodes (175 cm2 each were placed bilaterally on the proximal and distal quadriceps and hamstrings muscle groups and subtetanic contractions were elicited using a handheld NMES device. Lean body mass (LBM and other body composition variables were measured using dual-energy X-ray absorptiometry. Spasticity was measured using the Spinal Cord Assessment Tool for Spastic Reflexes (SCATs and visual analog scales. Verbal and written feedback was obtained to subjectively evaluate spasticity. LBM and spasticity measurements were taken before and after an 8 wk NMES training program in order to assess change. A statistically significant increase in lower-limb LBM, i.e., muscle tissue (p > 0.001, and a reduction in SCATs (p < 0.001 score, indicating reduced spasticity, was observed. Subjective responses were positive. Improvements in body composition and SCATs scores indicate that subtetanic NMES training elicits favorable responses and may have important clinical implications for an SCI population.

  2. Evaluation of Functional Electrical Stimulation to Assist Cycling in Four Adolescents with Spastic Cerebral Palsy

    Directory of Open Access Journals (Sweden)

    Ann Tokay Harrington

    2012-01-01

    Full Text Available Introduction. Adolescents with cerebral palsy (CP often have difficulty participating in exercise at intensities necessary to improve cardiovascular fitness. Functional electrical stimulation- (FES- assisted cycling is proposed as a form of exercise for adolescents with CP. The aims of this paper were to adapt methods and assess the feasibility of applying FES cycling technology in adolescents with CP, determine methods of performing cycling tests in adolescents with CP, and evaluate the immediate effects of FES assistance on cycling performance. Materials/Methods. Four participants (12–14 years old; GMFCS levels III-IV participated in a case-based pilot study of FES-assisted cycling in which bilateral quadriceps muscles were activated using surface electrodes. Cycling cadence, power output, and heart rate were collected. Results. FES-assisted cycling was well tolerated (n=4 and cases are presented demonstrating increased cadence (2–43 rpm, power output (19–70%, and heart rates (4-5% and decreased variability (8–13% in cycling performance when FES was applied, compared to volitional cycling without FES assistance. Some participants (n=2 required the use of an auxiliary hub motor for assistance. Conclusions. FES-assisted cycling is feasible for individuals with CP and may lead to immediate improvements in cycling performance. Future work will examine the potential for long-term fitness gains using this intervention.

  3. 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.

  4. 电刺激对脑梗死大鼠运动功能和Rho激酶表达的影响%Effects of electric stimulation on motor function and the expression of Rho kinase following cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    陈涛; 张秀清; 唐吉友

    2010-01-01

    目的 探讨单侧与双侧电刺激对脑梗死大鼠肢体运动功能和Rho激酶表达的影响.方法 采用线栓法制作Sprague-Dawley大鼠大脑中动脉永久性闭塞模型,将造模成功且存活的脑梗死大鼠分为假手术组、对照组、单侧电刺激组、双侧电刺激组(各36只),假手术组、对照组自然恢复,单、双侧电刺激组接受电刺激治疗.利用平衡木试验(BWT)观察造模后第3天、第7天、第14天和第21天各组大鼠运动功能恢复情况,同时采用免疫组化染色法检测脑梗死灶周边区Rho激酶的表达水平,采用2,3,5-氯化三苯基四氮唑(TTC)染色法检测脑梗死灶体积的变化.结果 第7,14,21天,电刺激组大鼠BWT评分明显高于对照组(P0.05),第21天脑梗死灶体积显著缩小(P0.05).结论 早期电刺激能够促进脑梗死大鼠运动功能的恢复,并且促进脑梗死灶体积缩小,双侧电刺激疗效优于单侧电刺激,其机制可能与下调脑梗死灶周边区Rho激酶的表达有关.%Objective To investigate the effects of electric stimulation on motor function and expression of Rho kinase following cerebral infarction in rats. Methods Acute cerebral infarction was modeled in adult male Sprague-Dawley ( SD) rats using the permanent middle cerebral artery occlusion ( PMCAO) technique. The rats were randomly divided into sham operation, control, unilateral electric stimulation and bilateral electric stimulation groups ( each group had 36 rats). Electric stimulation was applied to the paralyzed ( unilateral or bilateral) limbs in the last two groups. Motor function recovery and the expression of Rho kinase were examined using a beam walking test ( BWT) and immunohistochemistry respectively at the 3rd, 7th, 14th and 21st day after stimulation. In addition, the cerebral infarction volume was also determined by 2, 3, 5-triphenyl tetrazolium chloride (TTC) staining at different time points. Results Motor function improved significantly in the

  5. On-off control of burst high frequency electrical stimulation to suppress 4-AP induced seizures

    Science.gov (United States)

    Chiang, Chia-Chu; Lin, Chou-Ching K.; Ju, Ming-Shaung

    2013-06-01

    Objective. The goal of this study was to investigate, using model simulations and animal experiments, the efficiency and the side effects of burst high frequency stimulation combined with on-off control in seizure suppression. Approach. A modified mathematical hippocampal seizure model was created to provide evidence of the eligibility of this approach. In the experimental setup, two recording electrodes were inserted into bilateral septal CA1 of the hippocampus, and a stimulation electrode was placed on the ventral hippocampal commissure of a rat. After seizures had been induced by 4-aminopyridine treatment, on-off control stimulation was used to suppress the seizures at 20 s intervals. The stimulation time, cumulative charge and post-stimulation suppression were used to assess the effects of burst duration. Main results. The results showed that burst stimulation could suppress the seizures during the control period and burst stimulation of a shorter duration could keep the seizure suppressed with less effort. By decreasing the burst duration, the cumulative stimulation time became shorter, the delivered cumulative charge became lower, and the cumulative time of post-stimulation suppression became longer. Significance. The on-off control stimulation not only prolonged the duration of suppression but also avoided the side effects of the conversion of seizure patterns. In particular, decreasing the specified burst duration increased the efficiency of the burst stimulation.

  6. 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.

  7. Bacterial growth in ground beef prepared from electrically stimulated and nonstimulated muscles.

    OpenAIRE

    Butler, J L; Smith, G. C.; Savell, J W; Vanderzant, C.

    1981-01-01

    Ground beef samples prepared from electrically stimulated and nonstimulated biceps femoris and infraspinatus muscles were inoculated with Lactobacillus sp., Pseudomonas sp., Acinetobacter sp., or a mixture of Lactobacillus spp., Pseudomonas spp., Acinetobacter spp., Moraxella sp., Microbacterium thermosphactum, and Erwinia herbicola. There were no significant differences in growth of various bacteria in ground beef made from electrically stimulated and nonstimulated muscles.

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

    DEFF Research Database (Denmark)

    Komiyama, Osamu; Wang, Kelun; Svensson, Peter;

    2010-01-01

    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<0.01). CONCLUSIONS: 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...

  9. Use of transcutaneous electrical nerve stimulation for chronic pruritus.

    Science.gov (United States)

    Mohammad Ali, Basma Mourad; Hegab, Doaa Salah; El Saadany, Hanan Mohammad

    2015-01-01

    Pruritus is a distressing symptom in many dermatological as well as systemic conditions, and it is sometimes very chronic and relapsing. Transcutaneous electrical nerve stimulation (TENS) is an inexpensive form of analgesia that could also ameliorate itching. This study aimed to evaluate TENS efficacy in patients with pruritus due to some types of chronic eczema, and in patients with chronic hepatic disease. Ten patients with atopic dermatitis (AD), 20 patients with lichen simplex chronicus (LSC), and 16 patients with chronic liver disease having chronic distressing pruritus received three sessions of TENS weekly for 12 sessions, and the effect on the visual analogue scale (VAS) scores was recorded after 2 weeks of therapy, at treatment end, and after an additional month for follow up. There was a statistically significant decline in the mean VAS score for studied groups at weeks 2 and 4 of therapy compared to baseline, but the improvement was more significant in patients with AD, and LSC (p < 0.001 for both) than in those with chronic liver disease (p < 0.01) who also showed an early re-elevation of VAS score on follow up. TENS therapy holds promise as a palliative, alternative, safe and inexpensive treatment for patients with some chronic pruritic conditions. PMID:25973931

  10. Electrical stimulation for difficult wounds: only an alternative procedure?

    Science.gov (United States)

    Fraccalvieri, Marco; Salomone, Marco; Zingarelli, Enrico M; Rivarossa, Filippo; Bruschi, Stefano

    2015-12-01

    In the wound healing research, the exact mechanism of action of different modalities of electrical stimulation (ES) remains controversial and unresolved. In this study we discuss a particular ES, with a different type of waveform, corresponding to the principle of stochastic resonance. Between July 2008 and May 2010, 32 patients were enrolled and ES was applied to wounds using the bioelectrical signal therapy (BST) device (LifeWave, Petach Tiqwa, Israel). The outcome evaluated in group 1 (n = 21) was wound healing, while group 2 (n = 11) was evaluated for wound-related pain [Visual Number Scale (VNS) pain scale] during treatment. In group 1, 87% of the wounds closed in an average time of 97 days (range 10-150 days); three patients were lost to follow-up. In group 2, 45% of the patients experienced a complete pain disappearance after 7 days of treatment; 36% reported a reduction in VNS from 9·3 to 3·2 in 7 days; 19% stopped morphine-like painkillers after 2 weeks. The clinical application of the stochastic resonance enables the usage of easy-to-use, non-invasive, painless and pain-relief treatment. Our experience with ES has demonstrated the BST device to be a very good alternative in cases of small size defects, compared with other therapies such as surgery, dressing and negative pressure devices. PMID:24443795

  11. Electrical stimulation (ES counteracts muscle decline in seniors

    Directory of Open Access Journals (Sweden)

    Helmut eKern

    2014-07-01

    Full Text Available The loss in muscle mass coupled with a decrease in specific force and shift in fiber composition are all marks of aging. Training and regular exercise attenuate the signs of sarcopenia. However, pathologic conditions limit the ability to perform physical exercise.We addressed whether electrical stimulation (ES is an alternative intervention to improve muscle recovery and defined the molecular mechanism associated with improvement in muscle structure and function.We analyzed, at functional, structural, and molecular level, the effects of ES training on healthy seniors with normal life style, without routine sport activity.ES was able to improve muscle torque and functional performances of seniors and increased the size of fast muscle fibers. At molecular level, ES induced up-regulation of IGF-1 and modulation of MuRF1, a muscle-specific atrophy-related gene. ES also induced up-regulation of relevant markers of differentiating satellite cells and of extracellular matrix remodeling, which might guarantee shape and mechanical forces of trained skeletal muscle as well as maintenance of satellite cell function, reducing fibrosis.Our data provide evidence that ES is a safe method to counteract muscle decline associated with aging.

  12. FUNCTIONAL ELECTRICAL STIMULATION FOR CONTROL OF EPILEPTIC SEIZURES

    DEFF Research Database (Denmark)

    Jiao, Jianhang

    parameters regarding their ability to inhibit seizures. The present thesis hypothesized that the antiepileptic effects of vagus nerve stimulation and spinal cord stimulation could be improved by using higher stimulation frequencies than those that are currently used in clinic or proposed in the literature....

  13. 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.).

  14. Videoradiography at submental electrical stimulation during apnea in obstructive sleep apnea syndrome

    International Nuclear Information System (INIS)

    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.)

  15. The Neural Correlates of Long-Term Carryover following Functional Electrical Stimulation for Stroke

    OpenAIRE

    Marta Gandolla; Ward, Nick S; Franco Molteni; Eleonora Guanziroli; Giancarlo Ferrigno; Alessandra Pedrocchi

    2016-01-01

    Neurorehabilitation effective delivery for stroke is likely to be improved by establishing a mechanistic understanding of how to enhance adaptive plasticity. Functional electrical stimulation is effective at reducing poststroke foot drop; in some patients, the effect persists after therapy has finished with an unknown mechanism. We used fMRI to examine neural correlates of functional electrical stimulation key elements, volitional intent to move and concurrent stimulation, in a group of chron...

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

    OpenAIRE

    Adeyemi, Kazeem Dauda; Sazili, Awis Qurni

    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...

  17. Principles of electrical stimulation and dorsal column mapping as it relates to spinal cord stimulation: an overview.

    Science.gov (United States)

    Ramasubbu, Chitra; Flagg, Artemus; Williams, Kayode

    2013-02-01

    The last 30 years have witnessed the growth of spinal cord stimulation as a treatment modality for an increasing number of chronic pain conditions. In spite of this growth, one of the greatest criticisms is the lack of concrete evidence for the mechanism of action. With the ever increasing enlightenment with regards to the neurophysiology of pain, and the development of more dynamic neuroimaging techniques, the opportunity to better define the mechanism of action of the spinal cord stimulator will continue to expand. In the interim, clinicians will benefit from the consolidation of the available knowledge that will enhance the effective use of the device. This review serves to provide an overview of the key principles of electrical stimulation and dorsal column mapping as it relates to spinal cord stimulation. We aim at enhancing the understanding regarding the basis for successful placement of leads and manipulation of electrical parameters. PMID:23299905

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

    OpenAIRE

    Kroon, de, H.; 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 following stroke. Methods: A systematic literature search was performed to identify clinical trials evaluating the effect of electrical stimulation on motor control. The reported outcomes were exa...

  19. 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). PMID:19691937

  20. 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

  1. Superimposed electrical stimulation comfortably improves the endurance of maximal voluntary contractions.

    OpenAIRE

    Boisgontier, Matthieu; Moineau, Bastien; Nougier, Vincent

    2012-01-01

    AIM: Electrical stimulation has shown to improve muscle endurance in sub-maximal contractions but sessions were painful due to the electric stimuli parameters. Therefore, the present study tested the effects of the superimposed electrical stimulation technique using comfortable current on endurance in repetitions of maximal voluntary contraction. METHODS: Seventeen young healthy subjects performed fifty maximal voluntary contractions of the triceps brachii in two conditions of contraction (vo...

  2. Transcutaneous Electrical Nerve Stimulation Improves Exercise Tolerance in Healthy Subjects.

    Science.gov (United States)

    Tomasi, F P; Chiappa, G; Maldaner da Silva, V; Lucena da Silva, M; Lima, A S C G B; Arena, R; Bottaro, M; Cipriano, G

    2015-07-01

    Transcutaneous electrical nerve stimulation (TENS) increases peripheral blood flow by attenuation of the muscle metaboreflex, improving oxygen supply to working muscles. We tested the hypothesis that application of TENS at ganglion improves exercise performance. 11 subjects underwent constant-work rate tests (CWR) to the limit of tolerance (Tlim) while receiving TENS or placebo. Oxygen uptake (V.O2), carbon dioxide (V.CO2), minute ventilation (V.E), ventilatory equivalent (V.E/V.CO2), heart rate (HR) and oxygen pulse (V.O2/HR) were analyzed at isotime separated by percentile and Tlim. V.O2 was lower and V.CO2 was higher at 100% of isotime during TENS, while there were no differences in V.E and V.E/V.CO2. HR was lower during exercise with TENS, and V.O2/HR increased at peak exercise (17.96±1.9 vs. 20.38±1 ml/min/bpm, P<0.05). TENS increased mechanical efficiency at isotime and Tlim (4.10±0.50 vs. 3.39±0.52%, P<0.05 and 3.95±0.67 vs. 3.77±0.45%, P<0.05) and exercise tolerance compared to P-TENS (390±41 vs. 321±41 s; P<0.05). Our data shows that the application of TENS can potentially increase exercise tolerance and oxygen supply in healthy subjects. PMID:25607523

  3. Agent-based simulation of retail electricity markets: Bilateral trading players

    OpenAIRE

    Lopes, Fernando; Algarvio, Hugo; Coelho, Helder

    2013-01-01

    The electricity industry throughout the world, which has long been dominated by vertically integrated utilities, has experienced major changes. Deregulation, unbundling, wholesale and retail wheeling, and real-time pricing were abstract concepts a few years ago. Today market forces drive the price of electricity and reduce the net cost through increased competition. As power markets continue to evolve, there is a growing need for advanced modeling approaches. Accordingly, this article loo...

  4. Functional magnetic resonance imaging of the rat cerebellum during electrical stimulation of the fore- and hindpaw at 7 T

    Science.gov (United States)

    Peeters, Ronald; Verhoye, Marleen; Vos, Bart; De Schutter, Erik; Van der Linden, Anne-Marie

    1999-05-01

    Blood oxygenation level dependent contrast (BOLD) functional MRI responses at 7T were observed in the cerebellum of alpha- chloralose anesthetized rats in response to innocuous electrical stimulation of a forepaw or hindpaw. The responses were imaged in both coronal and sagittal slices which allowed for a clear delineation and localization of the observed activations. We demonstrate the validity of our fMRI protocol by imaging the responses in somatosensory cortex to the same stimuli and by showing a high level of reproducibility of the cerebellar responses. Widespread bilateral activations were found with mainly a patchy and medio-lateral band organization, more pronounced ipsilaterally. There was no overlap between the cerebellar activations caused by forepaw or hindpaw stimulation. Most remarkable was the overall horizontal organization of these responses: for both stimulation paradigms the patches and bands of activation were roughly positioned in either a cranial or caudal plane running antero-posteriorly through the whole cerebellum. This is the first fMRI study in the cerebellum of the rat. We relate our findings to the known projection patterns found with other techniques and to human fMRI studies. The horizontal organization found wasn't observed before in other studies using other techniques.

  5. The combined effect of electrical stimulation and resistance isometric contraction on muscle atrophy in rat tibialis anterior muscle.

    Science.gov (United States)

    Fujita, Naoto; Murakami, Shinichiro; Arakawa, Takamitsu; Miki, Akinori; Fujino, Hidemi

    2011-05-01

    Electrical stimulation has been used to prevent muscle atrophy, but this method is different in many previous studies, appropriate stimulation protocol is still not decided. Although resistance exercise has also been shown to be an effective countermeasure on muscle atrophy, almost previous studies carried out an electrical stimulation without resistance. It was hypothesized that electrical stimulation without resistance is insufficient to contract skeletal muscle forcefully, and the combination of electrical stimulation and forceful resistance contraction is more effective than electrical stimulation without resistance to attenuate muscle atrophy. This study investigated the combined effects of electrical stimulation and resistance isometric contraction on muscle atrophy in the rat tibialis anterior muscle. The animals were divided into control, hindlimb unloading (HU), hindlimb unloading plus electrical stimulation (ES), and hindlimb unloading plus the combination of electrical stimulation and resistance isometric contraction (ES+IC). Electrical stimulation was applied to the tibialis anterior muscle percutaneously for total 240 sec per day. In the ES+IC group, the ankle joint was fixed to produce resistance isometric contraction during electrical stimulation. After 7 days, the cross-sectional areas of each muscle fiber type in the HU group decreased. Those were prevented in the ES+IC group rather than the ES group. The expression of heat shock protein 72 was enhanced in the ES and ES+IC groups. These results indicated that although electrical stimulation is effective to prevent muscle atrophy, the combination of electrical stimulation and isometric contraction have further effect. PMID:21619551

  6. Bioreactor for modulation of cardiac microtissue phenotype by combined static stretch and electrical stimulation

    International Nuclear Information System (INIS)

    We describe here a bioreactor capable of applying electrical field stimulation in conjunction with static strain and on-line force of contraction measurements. It consisted of a polydimethylsiloxane (PDMS) tissue chamber and a pneumatically driven stretch platform. The chamber contained eight tissue microwells (8.05 mm in length and 2.5 mm in width) with a pair of posts (2.78 mm in height and 0.8 mm in diameter) in each well to serve as fixation points and for measurements of contraction force. Carbon rods, stimulating electrodes, were placed into the PDMS chamber such that one pair stimulated four microwells. For feasibility studies, neonatal rat cardiomyocytes were seeded in collagen gels into the microwells. Following 3 days of gel compaction, electrical field stimulation at 3–4 V cm−1 and 1 Hz, mechanical stimulation of 5% static strain or electromechanical stimulation (field stimulation at 3–4 V cm−1, 1 Hz and 5% static strain) were applied for 3 days. Cardiac microtissues subjected to electromechanical stimulation exhibited elevated amplitude of contraction and improved sarcomere structure as evidenced by sarcomeric α-actinin, actin and troponin T staining compared to microtissues subjected to electrical or mechanical stimulation alone or non-stimulated controls. The expression of atrial natriuretic factor and brain natriuretic peptide was also elevated in the electromechanically stimulated group. (papers)

  7. Ouabain-induced increases in resting tone of human hyperplastic prostate following repeated noradrenaline and electrical field stimulation.

    OpenAIRE

    Guh, J. H.; Ko, F. N.; Chueh, S. C.; Lai, M.K.; Teng, C. M.

    1996-01-01

    1. The effect of ouabain on contractions to repeated noradrenaline stimulation and electrical field stimulation of human hyperplastic prostate was examined. Ouabain (1 microM) did not induce contractile response per se but progressively increased the resting tone (i.e., the tone between one noradrenaline stimulation, or electrical field stimulation, and the following) of human hyperplastic prostate. 2. The increased tone by ouabain following repeated noradrenaline stimulations or electrical f...

  8. Treatment of Idiopathic Chronic Orchialgia with Transcutaneous Electrical Nerve Stimulation (TENS:A Preliminary Result

    Directory of Open Access Journals (Sweden)

    Ekrem Akdeniz

    2016-01-01

    Full Text Available 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. Medical history revealed that multiple conservative therapy attempts failed to alleviate the pain. Two of the patients had right sided ICO. Traditional TENS device is placed to the most painful points. TENS applied 3 times in a week with duration 30 minutes for 4 weeks. Before and after TENS application, patients were evaluated by using Visual Analog Scale (VAS at first and third months. Results: Median age of patients was 26.20±2.38 (22-30. Mean VAS value was 6.52 ± 0.89 before the procedure. After 1 month VAS value was 3.82 ± 0.83 (p0.05. None of the patients needed any analgesics after during the one month. No complications, hyperemia or hypoesthesia of the scrotal or penile skin, occurred after the procedure. Conclusion: TENS reduces pain by increasing endorphin release in the spinal cord dorsal horn. TENS is very effective method for first 1 month in patients with ICO but its effect reduces by the time. There is no standard therapeutic protocol for idiopathic chronic orchialgia. Therefore TENS may be an alternative for patients who do not benefit from medical therapy and do not want invasive procedures. Short-term use of TENS and low number of the patients are the limitations of this study. Randomized, placebo-controlled, and longer follow-up period studies are needed to better assess the efficacy of TENS for ICO.

  9. Effectiveness of transcutaneous electrical nerve stimulation and microcurrent electrical nerve stimulation in bruxism associated with masticatory muscle pain - A comparative study

    OpenAIRE

    Rajpurohit Bharat; Khatri Subhash; Metgud Deepa; Bagewadi Anjana

    2010-01-01

    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...

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

    International Nuclear Information System (INIS)

    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-1 to 0.333 S m-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

  11. Evaluation of Low-Intensity Transcutaneous Electrical Nerve Stimulation in Combination with Aspirin for Reduction of Controlled Thermal Sensation

    OpenAIRE

    Kajander, Keith C.

    1988-01-01

    Reductions in cutaneous thermal sensation produced by placebo, aspirin, transcutaneous electrical nerve stimulation, and transcutaneous electrical nerve stimulation plus aspirin were compared in 60 normal volunteers. The combination of transcutaneous electrical nerve stimulation plus aspirin produced a statistically significant reduction as compared with placebo. The results suggest this treatment combination may provide levels of analgesia useful for completion of minor dental procedures.

  12. 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.

  13. Bridging peripheral nerves using a deacetyl chitin conduit combined with short-term electrical stimulation

    Institute of Scientific and Technical Information of China (English)

    Zhongli Zhang; Xin Li; Songjie Zuo; Jie Xin; Peixun Zhang

    2014-01-01

    Previous studies have demonstrated that deacetyl chitin conduit nerve bridging or electrical stimulation can effectively promote the regeneration of the injured peripheral nerve. We hypoth-esized that the combination of these two approaches could result in enhanced regeneration. Rats with right sciatic nerve injury were subjected to deacetyl chitin conduit bridging combined with electrical stimulation (0.1 ms, 3 V, 20 Hz, for 1 hour). At 6 and 12 weeks after treatment, nerve conduction velocity, myelinated axon number, ifber diameter, axon diameter and the thickness of the myelin sheath in the stimulation group were better than in the non-stimulation group. The results indicate that deacetyl chitin conduit bridging combined with temporary electrical stimu-lation can promote peripheral nerve repair.

  14. Bridging peripheral nerves using a deacetyl chitin conduit combined with short-term electrical stimulation.

    Science.gov (United States)

    Zhang, Zhongli; Li, Xin; Zuo, Songjie; Xin, Jie; Zhang, Peixun

    2014-05-15

    Previous studies have demonstrated that deacetyl chitin conduit nerve bridging or electrical stimulation can effectively promote the regeneration of the injured peripheral nerve. We hypothesized that the combination of these two approaches could result in enhanced regeneration. Rats with right sciatic nerve injury were subjected to deacetyl chitin conduit bridging combined with electrical stimulation (0.1 ms, 3 V, 20 Hz, for 1 hour). At 6 and 12 weeks after treatment, nerve conduction velocity, myelinated axon number, fiber diameter, axon diameter and the thickness of the myelin sheath in the stimulation group were better than in the non-stimulation group. The results indicate that deacetyl chitin conduit bridging combined with temporary electrical stimulation can promote peripheral nerve repair. PMID:25206762

  15. Electrical stimulation in the bed nucleus of the stria terminalis alleviates severe obsessive-compulsive disorder.

    Science.gov (United States)

    Luyten, L; Hendrickx, S; Raymaekers, S; Gabriëls, L; Nuttin, B

    2016-09-01

    In 1998, we proposed deep brain stimulation as a last-resort treatment option for patients suffering from severe, treatment-resistant obsessive-compulsive disorder (OCD). Here, 24 OCD patients were included in a long-term follow-up study to evaluate the effects of electrical stimulation in the anterior limbs of the internal capsule (ALIC) and bed nucleus of the stria terminalis (BST). We find that electrical stimulation in the ALIC/BST area is safe and significantly decreases obsessions, compulsions, and associated anxiety and depressive symptoms, and improves global functioning in a blinded crossover trial (n=17), after 4 years (n=18), and at last follow-up (up to 171 months, n=24). Moreover, our data indicate that BST may be a better stimulation target compared with ALIC to alleviate OCD symptoms. We conclude that electrical stimulation in BST is a promising therapeutic option for otherwise treatment-resistant OCD patients. PMID:26303665

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

    OpenAIRE

    Walter J. Fagundes-Pereyra; Manoel Jacobsen Teixeira; Nicolas Reyns; Gustavo Touzet; Sérgio Dantas; Emmanuelle Laureau; Serge Blond

    2010-01-01

    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 reconstru...

  17. Loudness summation using focused and unfocused electrical stimulation

    OpenAIRE

    Padilla, Monica; David M Landsberger

    2014-01-01

    With a cochlear implant, when stimulation from multiple channels is interleaved, the perceived loudness is greater than the loudness associated with any of the individual channels presented in isolation. This phenomenon is known as loudness summation. This study examined if loudness summation with monopolar and tripolar stimulation were equivalent at two loudnesses and two spacing configurations. Results suggest that loudness summation is similar for monopolar and tripolar mode...

  18. 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.

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

    International Nuclear Information System (INIS)

    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-γ co-activator-1 (PGC-1α) 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.

  20. A reliable method for intracranial electrode implantation and chronic electrical stimulation in the mouse brain

    OpenAIRE

    Jeffrey, Melanie; Lang, Min; Gane, Jonathan; Wu, Chiping; Burnham, W McIntyre; Zhang, Liang

    2013-01-01

    Background Electrical stimulation of brain structures has been widely used in rodent models for kindling or modeling deep brain stimulation used clinically. This requires surgical implantation of intracranial electrodes and subsequent chronic stimulation in individual animals for several weeks. Anchoring screws and dental acrylic have long been used to secure implanted intracranial electrodes in rats. However, such an approach is limited when carried out in mouse models as the thin mouse skul...

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

    OpenAIRE

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

  2. Effects of Electrical Stimulation on Lipid Oxidation and Warmed-over Flavor of Precooked Roast Beef

    OpenAIRE

    Cheng, Jen-Hua; Ockerman, Herbert W.

    2013-01-01

    Many manufacturing processes damage the structure of meat products and this often contributes to lipid oxidation which could influence warmed-over flavor (WOF) in precooked beef that is reheated beef. Electrical stimulation causes contraction of muscles and improves tissue tenderization. The purpose of this study was to evaluate the rate of lipid oxidation or warmed-over flavor that could be affected by electrical stimulation of precooked roast beef after refrigerated storage and reheating. T...

  3. Electrical Stimulation of the Suprahyoid Muscles in Brain-injured Patients with Dysphagia: A Pilot Study

    OpenAIRE

    Beom, Jaewon; Kim, Sang Jun; Han, Tai Ryoon

    2011-01-01

    Objective To investigate the therapeutic effects of repetitive electrical stimulation of the suprahyoid muscles in brain-injured patients with dysphagia. Method Twenty-eight brain-injured patients who showed reduced laryngeal elevation and supraglottic penetration or subglottic aspiration during a videofluoroscopic swallowing study (VFSS) were selected. The patients received either conventional dysphagia management (CDM) or CDM with repetitive electrical stimulation of the suprahyoid muscles ...

  4. Synchronization of Ghostburster neuron in external electrical stimulation via H∞ variable universe fuzzy adaptive control

    International Nuclear Information System (INIS)

    In this paper, H∞ variable universe fuzzy adaptive control law is derived and applied to synchronize two unidirectional coupled Ghostbursters neurons under external electrical stimulation. Firstly, the dynamical behavior of the nonlinear Ghostburster model responding to various external electrical stimulations is studied. Then, using the results of the analysis, a robust adaptive variable universe fuzzy control scheme is designed to synchronize two unidirectional coupled neurons. Numerical simulations demonstrate the validity and feasibility of the proposed method.

  5. Bridging peripheral nerves using a deacetyl chitin conduit combined with short-term electrical stimulation

    OpenAIRE

    Zhang, Zhongli; Xin LI; Zuo, Songjie; Xin, Jie; Zhang, Peixun

    2014-01-01

    Previous studies have demonstrated that deacetyl chitin conduit nerve bridging or electrical stimulation can effectively promote the regeneration of the injured peripheral nerve. We hypothesized that the combination of these two approaches could result in enhanced regeneration. Rats with right sciatic nerve injury were subjected to deacetyl chitin conduit bridging combined with electrical stimulation (0.1 ms, 3 V, 20 Hz, for 1 hour). At 6 and 12 weeks after treatment, nerve conduction velocit...

  6. Effects of swallowing training combined with low-frequency electrical stimulation on dysphagia after ischemic stroke

    OpenAIRE

    Zhi-zhong ZHU; Li-ling CUI; Miao-miao YIN; Yu, Yang; Hong-tu WANG

    2015-01-01

    Objective To investigate the effects of swallowing training combined with low-frequency electrical stimulation on dysphagia after ischemic stroke.  Methods A total of 68 patients with dysphagia after ischemic stroke were divided into control group (N = 34, receiving swallowing training and feeding strategies) and combined treatment group (N = 34, receiving swallowing training, feeding strategies and low-frequency electrical stimulation). Video Fluoroscopic Swallowing Study (VFSS) and St...

  7. Electrical stimulation of smooth muscle strips from the urinary bladder of the pig

    NARCIS (Netherlands)

    R. van Mastrigt (Ron); J.J. Glerum (Jacobus)

    1985-01-01

    textabstractStrips of smooth muscle from pig urinary bladders were electrically stimulated to contract. Stimulation parameters and conditions were optimized so as to obtain a maximum number of isometric contractions with maximal force. It was found that the contractions could be described mathematic

  8. 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

  9. 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 t

  10. Effects of Electrical Stimulation on Lipid Oxidation and Warmed-over Flavor of Precooked Roast Beef.

    Science.gov (United States)

    Cheng, Jen-Hua; Ockerman, Herbert W

    2013-02-01

    Many manufacturing processes damage the structure of meat products and this often contributes to lipid oxidation which could influence warmed-over flavor (WOF) in precooked beef that is reheated beef. Electrical stimulation causes contraction of muscles and improves tissue tenderization. The purpose of this study was to evaluate the rate of lipid oxidation or warmed-over flavor that could be affected by electrical stimulation of precooked roast beef after refrigerated storage and reheating. The results show that there was no significant difference between chemical compositions and cooking yields when comparing non-electrically stimulated and electrically stimulated roast beef. Moreover, electrical stimulation had no significant effect on oxidative stability and off-flavor problems of precooked roast beef as evaluated by thiobarbituric acid reactive substances (TBARS) and sensory test (warmed-over aroma and warmed-over flavor). However, there was an increased undesirable WOF and a decrease in tenderness for both ES and Non-ES treatments over refrigerated storage time. Electrical stimulation did cause reactions of amino acids or other compounds to decrease the desirable beef flavor in re-cooked meat. PMID:25049788

  11. Manganese-enhanced MR imaging of brain activation evoked by noxious peripheral electrical stimulation.

    Science.gov (United States)

    Cha, Myeounghoon; Lee, Kyuhong; Lee, Chulhyun; Cho, Jee-Hyun; Cheong, Chaejoon; Sohn, Jin-Hun; Lee, Bae Hwan

    2016-02-01

    As imaging technology develops, magnetic resonance imaging (MRI) has furthered our understanding of brain function by clarifying the anatomical structure and generating functional imaging data related to information processing in pain conditions. Recent studies have reported that manganese (Mn(2+))-enhanced MRI (MEMRI) provides valuable information about the functions of the central nervous system. The aim of this study was to identify specific brain regions activated during noxious electric stimulation using high-resolution MEMRI. Male Sprague Dawley rats were divided into three groups: naïve, sham electrical stimulation, and noxious electric stimulation. Under urethane with α-chloralose mixture anesthesia, a catheter was placed in the external carotid artery to administrate 20% mannitol and manganese chloride (25mM MnCl2). Noxious electric stimulation (2Hz, 10V) was applied to the hind paw with a needle electrode. Stimulation-induced neuronal activation was detected using 4.7-T MRI. In response to noxious electrical stimulation, remarkable Mn(2+)-enhanced signals were observed in the agranular insular cortex, auditory cortex, primary somatosensory cortex of the hind limb, and granular and dysgranular insular cortex, which correspond to sensory tactile electric stimulus to the hindpaws. These results indicate that the combination of MEMRI with activity-induced Mn(2+)-dependent contrast can delineate functional areas in the rat brain. PMID:26733299

  12. Efficacy and safety of bilateral continuous theta burst stimulation (cTBS for the treatment of chronic tinnitus: design of a three-armed randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Plontke Stefan K

    2009-08-01

    Full Text Available Abstract Background Tinnitus, the perception of sound and noise in absence of an auditory stimulus, has been shown to be associated with maladaptive neuronal reorganization and increased activity of the temporoparietal cortex. Transient modulation of tinnitus by repetitive transcranial magnetic stimulation (rTMS indicated that these areas are critically involved in the pathophysiology of tinnitus and suggested new treatment strategies. However, the therapeutic efficacy of rTMS in tinnitus is still unclear, individual response is variable, and the optimal stimulation area disputable. Recently, continuous theta burst stimulation (cTBS has been put forward as an effective rTMS protocol for the reduction of pathologically enhanced cortical excitability. Methods 48 patients with chronic subjective tinnitus will be included in this randomized, placebo controlled, three-arm trial. The treatment consists of two trains of cTBS applied bilaterally to the secondary auditory cortex, the temporoparietal associaction cortex, or to the lower occiput (sham condition every working day for four weeks. Primary outcome measure is the change of tinnitus distress as quantified by the Tinnitus Questionnaire (TQ. Secondary outcome measures are tinnitus loudness and annoyance as well as tinnitus change during and after treatment. Audiologic and speech audiometric measurements will be performed to assess potential side effects. The aim of the present trail is to investigate effectiveness and safety of a four weeks cTBS treatment on chronic tinnitus and to compare two areas of stimulation. The results will contribute to clarify the therapeutic capacity of rTMS in tinnitus. Trial registration The trial was registered with the clinical trials register of http://www.clinicaltrials.gov (NCT00518024.

  13. On the Cause and Control of Residual Voltage Generated by Electrical Stimulation of Neural Tissue

    Science.gov (United States)

    Krishnan, Ashwati; Kelly, Shawn K.

    2016-01-01

    Functional electrical stimulation of neural tissue is traditionally performed with symmetric cathodic-first biphasic pulses of current through an electrode/electrolyte interface. When the interface is modeled by a series R-C circuit, as is sometimes done for stimulator circuit design, the appearance of a net residual voltage across the electrode cannot be explained. Residual voltage can cause polarization of the electrode and pose a problem for safe electrical stimulation. This paper aims to (1) theoretically explain one reason for the residual voltage, which is the inclusion of the Faradaic impedance (2) suggest a simple dynamic feedback mechanism to eliminate residual voltage. PMID:23366780

  14. Intrusive Thoughts Elicited by Direct Electrical Stimulation during Stereo-Electroencephalography.

    Science.gov (United States)

    Popa, Irina; Donos, Cristian; Barborica, Andrei; Opris, Ioan; Mălîia, Mihai Dragoş; Ene, Mirela; Ciurea, Jean; Mîndruţă, Ioana

    2016-01-01

    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. PMID:27486431

  15. Resuscitation therapy for traumatic brain injury-induced coma in rats: mechanisms of median nerve electrical stimulation

    OpenAIRE

    Zhen Feng; Ying-jun Zhong; Liang Wang; Tian-qi Wei

    2015-01-01

    In this study, rats were put into traumatic brain injury-induced coma and treated with median nerve electrical stimulation. We explored the wake-promoting effect, and possible mechanisms, of median nerve electrical stimulation. Electrical stimulation upregulated the expression levels of orexin-A and its receptor OX1R in the rat prefrontal cortex. Orexin-A expression gradually increased with increasing stimulation, while OX1R expression reached a peak at 12 hours and then decreased. In additio...

  16. The combined effect of electrical stimulation and resistance isometric contraction on muscle atrophy in rat tibialis anterior muscle

    OpenAIRE

    Fujita, Naoto; Murakami, Shinichiro; Arakawa, Takamitsu; Miki, Akinori; Fujino, Hidemi

    2011-01-01

    Electrical stimulation has been used to prevent muscle atrophy, but this method is different in many previous studies, appropriate stimulation protocol is still not decided. Although resistance exercise has also been shown to be an effective countermeasure on muscle atrophy, almost previous studies carried out an electrical stimulation without resistance. It was hypothesized that electrical stimulation without resistance is insufficient to contract skeletal muscle forcefully, and the combinat...

  17. [Interest of EEG recording during direct electrical stimulation for brain mapping function in surgery].

    Science.gov (United States)

    Trebuchon, A; Guye, M; Tcherniack, V; Tramoni, E; Bruder, N; Metellus, P

    2012-06-01

    Brain tumor surgery is at risk when lesions are located in eloquent areas. The interindividual anatomo-functional variability of the central nervous system implies that brain surgery within eloquent regions may induce neurological sequelae. Brain mapping using intraoperative direct electrical stimulation in awake patients has been for long validated as the standard for functional brain mapping. Direct electrical stimulation inducing a local transient electrical and functional disorganization is considered positive if the task performed by the patient is disturbed. The brain area stimulated is then considered as essential for the function tested. However, the exactitude of the information provided by this technique is cautious because the actual impact of cortical direct electrical stimulation is not known. Indeed, the possibility of false negative (insufficient intensity of the stimulation due to the heterogeneity of excitability threshold of different cortical areas) or false positive (current spread, interregional signal propagation responsible for remote effects, which make difficult the interpretation of positive or negative behavioural effects) constitute a limitation of this technique. To improve the sensitivity and specificity of this technique, we used an electrocorticographic recording system allowing a real time visualization of the local. We provide here evidence that direct cortical stimulation combined with electrocorticographic recording could be useful to detect remote after discharge and to adjust stimulation parameters. In addition this technique offers new perspective to better assess connectivity of cerebral networks. PMID:22683402

  18. Treatment of refractory chest angina with spinal electrical stimulator: literature review

    International Nuclear Information System (INIS)

    There is a group of patients with chronic refractory chest angina, who are not ideal candidates for surgical or percutaneous revascularization and who although having a good medical handling continues to experience severe episodes of angina. The spinal electrical stimulator is a neuromodulators used as an alternative to treat these patients. The objective is to realize a review of scientific literature regarding the spinal electric stimulation in the treatment of chest angina, its mechanism of action, benefits and its cost effectiveness. Materials and methods: using the Cochrane methodology, a search of articles published from January 1980 to January 2007 in Medline using the terms spinal cord stimulation, was realized. The papers considered most pertinent were selected. Conclusions: the anti-ischemic effect of the electrical spinal stimulator reduces the episodes of chest angina, improves the quality of life and the tolerance to exercise, diminishes the hospital stay and delays the appearance of ischemic signs

  19. Applied electric field enhances DRG neurite growth: influence of stimulation media, surface coating and growth supplements

    Science.gov (United States)

    Wood, Matthew D.; Willits, Rebecca Kuntz

    2009-08-01

    Electrical therapies have been found to aid repair of nerve injuries and have been shown to increase and direct neurite outgrowth during stimulation. This enhanced neural growth existed even after the electric field (EF) or stimulation was removed, but the factors that may influence the enhanced growth, such as stimulation media or surface coating, have not been fully investigated. This study characterized neurite outgrowth and branching under various conditions: EF magnitude and application time, ECM surface coating, medium during EF application and growth supplements. A uniform, low-magnitude EF (24 or 44 V m-1) was applied to dissociated chick embryo dorsal root ganglia seeded on collagen or laminin-coated surfaces. During the growth period, cells were either exposed to NGF or N2, and during stimulation cells were exposed to either unsupplemented media (Ca2+) or PBS (no Ca2+). Parallel controls for each experiment included cells exposed to the chamber with no stimulation and cells remaining outside the chamber. After brief electrical stimulation (10 min), neurite length significantly increased 24 h after application for all conditions studied. Of particular interest, increased stimulation time (10-100 min) further enhanced neurite length on laminin but not on collagen surfaces. Neurite branching was not affected by stimulation on any surface, and no preferential growth of neurites was noted after stimulation. Overall, the results of this report suggest that short-duration electric stimulation is sufficient to enhance neurite length under a variety of conditions. While further data are needed to fully elucidate a mechanism for this increased growth, these data suggest that one focus of those investigations should be the interaction between the growth cone and the substrata.

  20. 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.

  1. Dynamic response of the human retina to pulsed optical and electrical stimulation

    Science.gov (United States)

    Akchurin, Garif G.; Bakutkin, Valery V.; Kamenskih, Tatyana G.; Zemskova, Tatyana M.; Ahuja, Poonam

    2000-04-01

    Transcutaneous millisecond stimulation of the retina by electric pulses is used for diagnosis, determination of the extent of optic nerve damage, and also partial restoration of visual function in patients with glaucoma, myopia and different types of optic nerve atrophy. Correlation between the threshold of phosphen formation and duration of the stimulating electric pulses was determined experimentally in normal eyes and in eyes with various pathologies. Comparison of optical and electrical scintillating frequency gives information about the dynamic processes in the normal and pathological retina.

  2. A model of auditory nerve responses to electrical stimulation

    DEFF Research Database (Denmark)

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

    peripheral for the cathodic phase. This results in an average difference of 200 μs in spike latency for AP generated by anodic vs cathodic pulses. It is hypothesized here that this difference is large enough to corrupt the temporal coding in the AN. To quantify effects of pulse polarity on auditory...... as a framework to test various stimulation strategies and to quantify their effect on the performance of CI listeners in psychophysical tasks....

  3. [Exploration Research of Treatment Effect Improvement of Transcutaneous Electrical Nerve Stimulation Using Parameter-changing Chaotic Signal].

    Science.gov (United States)

    Zheng, Jincun; Zhang, Hui; Qin, Binyi; Wang, Hai; Nie, Guochao; Chen, Tiejun

    2015-10-01

    This article presents a transcutaneous electric stimulator that is based on chaotic signal. Firstly, we in the study used the MATLAB platform in the PC to generate chaotic signal through the chaos equation, and then we transferred the signal out by data acquisition equipment of USB-6251 manufactured by NI Company. In order to obtain high-power signal for transcutaneous electric stimulator, we used the chip of LM3886 to amplify the signal. Finally, we used the power-amplified chaotic signal to stimulate the internal nerve of human through the electrodes fixed on the skin. We obtained different stimulation effects of transcutaneous electric stimulator by changing the parameters of chaotic model. The preliminary test showed that the randomness of chaotic signals improved the applicability of electrical stimulation and the rules of chaos ensured that the stimulation was comfort. The method reported in this paper provides a new way for the design of transcutaneous electric stimulator. PMID:26964307

  4. 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

  5. Electrical stimulation as a biomimicry tool for regulating muscle cell behavior

    OpenAIRE

    Ahadian, Samad; Ostrovidov, Serge; Hosseini, Vahid; Kaji, Hirokazu; Ramalingam, Murugan; Bae, Hojae; Khademhosseini, Ali

    2013-01-01

    There is a growing need to understand muscle cell behaviors and to engineer muscle tissues to replace defective tissues in the body. Despite a long history of the clinical use of electric fields for muscle tissues in vivo, electrical stimulation (ES) has recently gained significant attention as a powerful tool for regulating muscle cell behaviors in vitro. ES aims to mimic the electrical environment of electroactive muscle cells (e.g., cardiac or skeletal muscle cells) by helping to regulate ...

  6. Neurite outgrowth on electrospun PLLA fibers is enhanced by exogenous electrical stimulation

    Science.gov (United States)

    Koppes, A. N.; Zaccor, N. W.; Rivet, C. J.; Williams, L. A.; Piselli, J. M.; Gilbert, R. J.; Thompson, D. M.

    2014-08-01

    Objective. Both electrical stimuli (endogenous and exogenous) and topographical cues are instructive to axonal extension. This report, for the first time, investigated the relative dominance of directional topographical guidance cues and directional electrical cues to enhance and/or direct primary neurite extension. We hypothesized the combination of electrical stimulation with electrospun fiber topography would induce longer neurite extension from dorsal root ganglia neurons than the presence of electrical stimulation or aligned topography alone. Approach. To test the hypothesis, neurite outgrowth was examined on laminin-coated poly-L-lactide films or electrospun fibers (2 µm in diameter) in the presence or absence of electrical stimulation. Immunostained neurons were semi-automatically traced using Neurolucida software and morphology was evaluated. Main Results. Neurite extension increased 74% on the aligned fibers compared to film controls. Stimulation alone increased outgrowth by 32% on films or fibers relative to unstimulated film controls. The co-presentation of topographical (fibers) with biophysical (electrical stimulation) cues resulted in a synergistic 126% increase in outgrowth relative to unstimulated film controls. Field polarity had no influence on the directionality of neurites, indicating topographical cues are responsible for guiding neurite extension. Significance. Both cues (electrical stimulation and fiber geometry) are modular in nature and can be synergistically applied in conjunction with other common methods in regenerative medicine such as controlled release of growth factors to further influence axonal growth in vivo. The combined application of electrical and aligned fiber topographical guidance cues described herein, if translated in vivo, could provide a more supportive environment for directed and robust axonal regeneration following peripheral nerve injury.

  7. Effortful swallowing training combined with electrical stimulation in post-stroke dysphagia: a randomized controlled study.

    Science.gov (United States)

    Park, Jin-Woo; Kim, Youngsun; Oh, Jong-Chi; Lee, Ho-Jun

    2012-12-01

    We tested the effect of effortful swallow combined with surface electrical stimulation used as a form of resistance training in post-stroke patients with dysphagia. Twenty post-stroke dysphagic patients were randomly divided into two groups: those who underwent effortful swallow with infrahyoid motor electrical stimulation (experimental group, n = 10) and effortful swallow with infrahyoid sensory electrical stimulation (control group, n = 10). In the experimental group, electrical stimulation was applied to the skin above the infrahyoid muscle with the current was adjusted until muscle contraction occurred and the hyoid bone was depressed. In the control group, the stimulation intensity was applied just above the sensory threshold. The patients in both groups were then asked to swallow effortfully in order to elevate their hyolaryngeal complex when the stimulation began. A total of 12 sessions of 20 min of training for 4 weeks were performed. Blinded biomechanical measurements of the extent of hyolaryngeal excursion, the maximal width of the upper esophageal sphincter (UES) opening, and the penetration-aspiration scale before and after training were performed. In the experimental group, the maximal vertical displacement of the larynx was increased significantly after the intervention (p method in post-stroke patients with dysphagia. PMID:22447240

  8. ELECTRICAL STIMULATION OF THE SKIN--A SELECTED BIBLIOGRAPHY.

    Science.gov (United States)

    GIBSON, ROBERT H., COMP.

    ONE OF A SERIES OF PROVISIONAL BIBLIOGRAPHIES IN THE FIELD OF SENSORY RESEARCH RELATED TO SENSORY (ESPECIALLY VISUAL) IMPAIRMENT, THE DOCUMENT LISTS 284 SELECTED WORKS ON ELECTRICAL STIMUATION OF SKIN. PRIMARILY JOURNAL ARTICLES, BUT INCLUDING SOME BOOKS AND SEVERAL THESES, THE ITEMS DATE FROM 1891 THROUGH 1967 (IN PRESS). PUBLICATIONS CITED ARE…

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

    Institute of Scientific and Technical Information of China (English)

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

    2013-01-01

    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 Mackin-non’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. Histo-logical observation revealed that intraoperative electric stimulation and decimeter wave therapy could improve the local blood circulation of repaired sites, al eviate 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 rege-neration. 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.

  10. Effects of BAY K 8644 on the responses of rabbit ear artery to electrical stimulation

    International Nuclear Information System (INIS)

    BAY K 8644 at 6.25 nM to 1 microM enhanced, in a concentration-dependent manner, both phases of the vasoconstrictor response of the isolated perfused rabbit ear artery to electrical stimulation. At 1 microM, BAY K 8644 enhanced the constrictor response by more than 250%. To study possible involvement of neurotransmitter release in the enhancement of the vasoconstrictor response by BAY K 8644, rabbit ear arteries were preincubated with [3H]norepinephrine and stimulated either electrically (for 1 or 5 min) or by 60 mM K+. BAY K 8644 (1 microM) had no effect on tritium release caused by 1-min periods of electrical stimulation. However, tritium release caused by 5-min periods of electrical stimulation or by 60 mM K+ was enhanced in the presence of BAY K 8644. It was concluded that BAY K 8644 enhances vasoconstrictor effects of electrical stimulation of rabbit ear artery by primarily a direct agonist action on Ca2+ channels in vascular smooth muscle cells. Following sustained depolarization, however, the drug may also enhance the release of neurotransmitter from sympathetic nerve endings. Under certain conditions, this release may contribute to the overall action of BAY K 8644

  11. 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.

  12. 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.

  13. Evaluation of the brain activation induced by functional electrical stimulation and voluntary contraction using functional magnetic resonance imaging

    Directory of Open Access Journals (Sweden)

    Joa Kyung-Lim

    2012-07-01

    Full Text Available Abstract Background To observe brain activation induced by functional electrical stimulation, voluntary contraction, and the combination of both using functional magnetic resonance imaging (fMRI. Methods Nineteen healthy young men were enrolled in the study. We employed a typical block design that consisted of three sessions: voluntary contraction only, functional electrical stimulation (FES-induced wrist extension, and finally simultaneous voluntary and FES-induced movement. MRI acquisition was performed on a 3.0 T MR system. To investigate activation in each session, one-sample t-tests were performed after correcting for false discovery rate (FDR; p t-test was performed using a contrast map (p  Results In the voluntary contraction alone condition, brain activation was observed in the contralateral primary motor cortex (MI, thalamus, bilateral supplementary motor area (SMA, primary sensory cortex (SI, secondary somatosensory motor cortex (SII, caudate, and cerebellum (mainly ipsilateral. During FES-induced wrist movement, brain activation was observed in the contralateral MI, SI, SMA, thalamus, ipsilateral SII, and cerebellum. During FES-induced movement combined with voluntary contraction, brain activation was found in the contralateral MI, anterior cingulate cortex (ACC, SMA, ipsilateral cerebellum, bilateral SII, and SI. The activated brain regions (number of voxels of the MI, SI, cerebellum, and SMA were largest during voluntary contraction alone and smallest during FES alone. SII-activated brain regions were largest during voluntary contraction combined with FES and smallest during FES contraction alone. The brain activation extent (maximum t score of the MI, SI, and SII was largest during voluntary contraction alone and smallest during FES alone. The brain activation extent of the cerebellum and SMA during voluntary contraction alone was similar during FES combined with voluntary contraction; however, cerebellum and SMA activation

  14. Ex Vivo Assay of Electrical Stimulation to Rat Sciatic Nerves: Cell Behaviors and Growth Factor Expression.

    Science.gov (United States)

    Du, Zhiyong; Bondarenko, Olexandr; Wang, Dingkun; Rouabhia, Mahmoud; Zhang, Ze

    2016-06-01

    Neurite outgrowth and axon regeneration are known to benefit from electrical stimulation. However, how neuritis and their surroundings react to electrical field is difficult to replicate by monolayer cell culture. In this work freshly harvested rat sciatic nerves were cultured and exposed to two types of electrical field, after which time the nerve tissues were immunohistologically stained and the expression of neurotrophic factors and cytokines were evaluated. ELISA assay was used to confirm the production of specific proteins. All cell populations survived the 48 h culture with little necrosis. Electrical stimulation was found to accelerate Wallerian degeneration and help Schwann cells to switch into migratory phenotype. Inductive electrical stimulation was shown to upregulate the secretion of multiple neurotrophic factors. Cellular distribution in nerve tissue was altered upon the application of an electrical field. This work thus presents an ex vivo model to study denervated axon in well controlled electrical field, bridging monolayer cell culture and animal experiment. It also demonstrated the critical role of electrical field distribution in regulating cellular activities. PMID:26516696

  15. Electric field stimulation setup for photoemission electron microscopes

    International Nuclear Information System (INIS)

    Manipulating magnetisation by the application of an electric field in magnetoelectric multiferroics represents a timely issue due to the potential applications in low power electronics and the novel physics involved. Thanks to its element sensitivity and high spatial resolution, X-ray photoemission electron microscopy is a uniquely suited technique for the investigation of magnetoelectric coupling in multiferroic materials. In this work, we present a setup that allows for the application of in situ electric and magnetic fields while the sample is analysed in the microscope. As an example of the performances of the setup, we present measurements on Ni/Pb(Mg0.66Nb0.33)O3-PbTiO3 and La0.7Sr0.3MnO3/PMN-PT artificial multiferroic nanostructures

  16. Electric field stimulation setup for photoemission electron microscopes

    Energy Technology Data Exchange (ETDEWEB)

    Buzzi, M.; Vaz, C. A. F.; Raabe, J.; Nolting, F., E-mail: frithjof.nolting@psi.ch [Paul Scherrer Institut, 5232 Villigen PSI (Switzerland)

    2015-08-15

    Manipulating magnetisation by the application of an electric field in magnetoelectric multiferroics represents a timely issue due to the potential applications in low power electronics and the novel physics involved. Thanks to its element sensitivity and high spatial resolution, X-ray photoemission electron microscopy is a uniquely suited technique for the investigation of magnetoelectric coupling in multiferroic materials. In this work, we present a setup that allows for the application of in situ electric and magnetic fields while the sample is analysed in the microscope. As an example of the performances of the setup, we present measurements on Ni/Pb(Mg{sub 0.66}Nb{sub 0.33})O{sub 3}-PbTiO{sub 3} and La{sub 0.7}Sr{sub 0.3}MnO{sub 3}/PMN-PT artificial multiferroic nanostructures.

  17. Electric field stimulation setup for photoemission electron microscopes

    Science.gov (United States)

    Buzzi, M.; Vaz, C. A. F.; Raabe, J.; Nolting, F.

    2015-08-01

    Manipulating magnetisation by the application of an electric field in magnetoelectric multiferroics represents a timely issue due to the potential applications in low power electronics and the novel physics involved. Thanks to its element sensitivity and high spatial resolution, X-ray photoemission electron microscopy is a uniquely suited technique for the investigation of magnetoelectric coupling in multiferroic materials. In this work, we present a setup that allows for the application of in situ electric and magnetic fields while the sample is analysed in the microscope. As an example of the performances of the setup, we present measurements on Ni/Pb(Mg0.66Nb0.33)O3-PbTiO3 and La0.7Sr0.3MnO3/PMN-PT artificial multiferroic nanostructures.

  18. Electrical stimulation with multichannel electrodes in deaf patients.

    Science.gov (United States)

    Burian, K; Hochmair, E; Hochmair-Desoyer, I; Lessel, M R

    1980-01-01

    Design and function of a 6- or 8-channel electrode assembly, which was introduced through the round window into the scala tympani, are described. Two different receiver systems, a more simple one with reed contacts and a more complex one in hybrid technology, are also described. Signal and energy are delivered transcutaneously via inductively coupled coils. The results of the electrical tests are described and discussed. PMID:6892764

  19. 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

  20. Electrical stimulation treatment for facial palsy after revision pleomorphic adenoma surgery

    Science.gov (United States)

    Goldie, Simon; Sandeman, Jack; Cole, Richard; Dennis, Simon; Swain, Ian

    2016-01-01

    Surgery for pleomorphic adenoma recurrence presents a significant risk of facial nerve damage that can result in facial weakness effecting patients’ ability to communicate, mental health and self-image. We report two case studies that had marked facial weakness after resection of recurrent pleomorphic adenoma and their progress with electrical stimulation. Subjects received electrical stimulation twice daily for 24 weeks during which photographs of expressions, facial measurements and Sunnybrook scores were recorded. Both subjects recovered good facial function demonstrating Sunnybrook scores of 54 and 64 that improved to 88 and 96, respectively. Neither subjects demonstrated adverse effects of treatment. We conclude that electrical stimulation is a safe treatment and may improve facial palsy in patients after resection of recurrent pleomorphic adenoma. Larger studies would be difficult to pursue due to the low incidence of cases. PMID:27106613

  1. Is there a role for ultrasound and electrical stimulation following injury to tendon and nerve?

    Science.gov (United States)

    Michlovitz, Susan L

    2005-01-01

    Ultrasound (US) and electrical stimulation have been widely used in hand therapy to promote recovery after nerve and tendon injuries. There is support for the use of low-dosage continuous wave and pulsed US for carpal tunnel syndrome and tendonitis. Iontophoresis with dexamethasone sodium phosphate can relieve pain in acute elbow tendonitis, but there is no support for phonophoresis for any tendonitis. Animal model research supports the use of low-dosage US to improve the mechanical properties of the Achilles tendon when initiated immediately after tenorrhaphy. There are no studies available which have examined US applied to tendons in humans after repair. Electrical stimulation has been extensively studied in animal models after nerve axonotmesis and neurotmesis with nerve repair, with some support of enhancing recovery. There is a void in the literature on the use of electrical stimulation for humans after nerve transection and repair. PMID:15891986

  2. Tuning and disrupting the brain – modulating the McGurk illusion with electrical stimulation

    Directory of Open Access Journals (Sweden)

    Lotfi B Merabet

    2014-08-01

    Full Text Available In the so-called McGurk illusion, when the synchronized presentation of the visual stimulus /ga/ is paired with the auditory stimulus /ba/, people in general hear it as /da/. Multisensory integration processing underlying this illusion seems to occur within the Superior Temporal Sulcus (STS. Herein, we present evidence demonstrating that bilateral cathodal transcranial direct current stimulation (tDCS of this area can decrease the McGurk illusion-type responses. Additionally, we show that the manipulation of this audio-visual integrated output occurs irrespective of the number of eye-fixations on the mouth of the speaker. Bilateral anodal tDCS of the Parietal Cortex also modulates the illusion, but in the opposite manner, inducing more illusion-type responses. This is the first demonstration of using non-invasive brain stimulation to modulate multisensory speech perception in an illusory context (i.e., both increasing and decreasing illusion-type responses to a verbal audio-visual integration task. These findings provide clear evidence that both the superior temporal and parietal areas contribute to multisensory integration processing related to speech perception. Specifically, STS seems fundamental for the temporal synchronization and integration of auditory and visual inputs. For its part, PPC may adjust the arrival of incoming audio and visual information to STS thereby enhancing their interaction in this latter area.

  3. Electrical stimulation of dog pudendal nerve regulates the excitatory pudendal-to-bladder reflex

    OpenAIRE

    Yan-he Ju; Li-min Liao

    2016-01-01

    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 pu...

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

    OpenAIRE

    van Rijn Clementina M; van Heck Casper H; van den Broeke Emanuel N; Wilder-Smith Oliver HG

    2011-01-01

    Abstract 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 to investigate HFS-induced central plasticity of sensory processing at the level of the brain using the electroencephalogram (EEG). To this end we measured evoked potentials in response to ...

  5. Flight behavior of the rhinoceros beetle Trypoxylus dichotomus during electrical nerve stimulation

    International Nuclear Information System (INIS)

    Neuronal stimulation is an intricate part of understanding insect flight behavior and control insect itself. In this study, we investigated the effects of electrical pulses applied to the brain and basalar muscle of the rhinoceros beetle (Trypoxylus dichotomus). To understand specific neuronal stimulation mechanisms, responses and flight behavior of the beetle, four electrodes were implanted into the two optic lobes, the brain's central complex and the ventral nerve cord in the posterior pronotum. We demonstrated flight initiation, turning and cessation by stimulating the brain. The change undergone by the wing flapping in response to the electrical signal was analyzed from a sequence of images captured by a high-speed camera. Here, we provide evidence to distinguish the important differences between neuronal and muscular flight stimulations in beetles. We found that in the neural potential stimulation, both the hind wing and the elytron were suppressed. Interestingly, the beetle stopped flying whenever a stimulus potential was applied between the pronotum and one side of the optic lobe, or between the ventral nerve cord in the posterior pronotum and the central complex. In-depth experimentation demonstrated the effective of neural stimulation over muscle stimulation for flight control. During electrical stimulation of the optic lobes, the beetle performed unstable flight, resulting in alternating left and right turns. By applying the electrical signal into both the optic lobes and the central complex of the brain, we could precisely control the direction of the beetle flight. This work provides an insight into insect flight behavior for future development of insect-micro air vehicle. (paper)

  6. Depression of corticomotor excitability after muscle fatigue induced by electrical stimulation and voluntary contraction

    OpenAIRE

    Shinichi Kotan

    2015-01-01

    In this study, we examined the effect of muscle fatigue induced by tetanic electrical stimulation (ES) and submaximal isometric contraction on corticomotor excitability. Experiments were performed in a cross-over design. Motor-evoked potentials (MEPs) were elicited by transcranial magnetic stimulation (TMS). Corticomotor excitability was recorded before and after thumb opposition muscle fatigue tasks, in which 10% of the maximal tension intensity was induced by tetanic ES or voluntary contrac...

  7. Electrical Stimulation of the Insular Region Attenuates Nicotine-Taking and Nicotine-Seeking Behaviors

    OpenAIRE

    Pushparaj, Abhiram; Hamani, Clement; Yu, Wilson; Shin, Damian S; Kang, Bin; Nobrega, José N; Le Foll, Bernard

    2012-01-01

    Pharmacological inactivation of the granular insular cortex is able to block nicotine-taking and -seeking behaviors in rats. In this study, we explored the potential of modulating activity in the insular region using electrical stimulation. Animals were trained to self-administer nicotine (0.03 mg/kg per infusion) under a fixed ratio-5 (FR-5) schedule of reinforcement followed by a progressive ratio (PR) schedule. Evaluation of the effect of stimulation in the insular region was performed on ...

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

    OpenAIRE

    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 to investigate HFS-induced central plasticity of sensory processing at the level of the brain using the electroencephalogram (EEG). To this end we measured evoked potentials in response to noxious e...

  9. Electrical potentials from the eye and optic nerve of Strombus: effects of electrical stimulation of the optic nerve.

    Science.gov (United States)

    Gillary, H L

    1977-02-01

    1. Photic stimulation of the mature eye of Strombus can evoke in the optic nerve 'on' activity in numerous small afferent fibres and repetitive 'off' bursts of afferent impulses in a smaller number of larger fibres. 2. Synchronous invasion of the eye by electrically evoked impulses in small optic nerve fibres (apparently the 'on' afferents, antidromically activated) can evoke a burst of impulses in the larger 'off' fibres which propagate away from the eye. Invasion of the eye via one branch of optic nerve can evoke an answering burst in another branch. 3. Such electrically evoked bursts are similar to light-evoked 'off' bursts with respect to their impulse composition, their ability to be inhibited by illumination of the eye, and their susceptibility to MgCl2 anaesthesia. 4. Invasion of the eye by a train of repetitive electrically evoked impulses in the absence of photic stimulation can give rise to repetitive 'off' bursts as well as concomitant oscillatory potentials in the eye which are similar to those normally evoked by cessation of a photic stimulus. 5. The electrically evoked 'off' bursts appear to be caused by an excitatory rebound following the cessation of inhibitory synaptic input from photoreceptors which can be antidromically activated by electrical stimulation of the optic nerve. 6. The experimental results suggest that the rhythmic discharge of the 'off' fibres evoked by the cessation of a photic stimulus is mediated by the abrupt decrease of inhibitory synaptic input from the receptors. PMID:192827

  10. Cyclical electrical stimulation increases strength and improves activity after stroke: a systematic review

    Directory of Open Access Journals (Sweden)

    Lucas R Nascimento

    2014-03-01

    Full Text Available Question: Does electrical stimulation increase strength after stroke and are any benefits maintained beyond the intervention period or carried over to activity? Design: Systematic review with meta-analysis of randomised or controlled trials. Participants: Adults who have had a stroke. Intervention: Cyclical electrical stimulation applied in order to increase muscle strength. Outcome measures: Strength measures had to be representative of maximum voluntary contraction and were obtained as continuous measures of force or torque, or ordinal measures such as manual muscle tests. Activity was measured using direct measures of performance that produced continuous or ordinal data, or with scales that produced ordinal data. Results: Sixteen trials representing 17 relevant comparisons were included in this systematic review. Effect sizes were calculated as standardised mean differences because various muscles were studied and different outcome measures were used. Overall, electrical stimulation increased strength by a standardised mean difference (SMD of 0.47 (95% CI 0.26 to 0.68 and this effect was maintained beyond the intervention period (SMD 0.33, 95% CI 0.07 to 0.60. Electrical stimulation also improved activity (SMD 0.30, 95% CI 0.05 to 0.56 and this effect was also maintained beyond the intervention period (SMD 0.38, 95% CI 0.09 to 0.66. Conclusion: Cyclical electrical stimulation increases strength and improves activity after stroke. These benefits were maintained beyond the intervention period with a small-to-moderate effect size. The sustained effect on activity suggests that the benefits were incorporated into daily life. Review registration: PROSPERO (CRD42013003895. [Nascimento LR, Michaelsen SM, Ada L, Polese JC, Teixeira-Salmela LF (2014 Cyclical electrical stimulation increases strength and improves activity after stroke: a systematic review. Journal of Physiotherapy 60: 22–30

  11. Technical aspects of neurostimulation: Focus on equipment, electric field modeling, and stimulation protocols.

    Science.gov (United States)

    Klooster, D C W; de Louw, A J A; Aldenkamp, A P; Besseling, R M H; Mestrom, R M C; Carrette, S; Zinger, S; Bergmans, J W M; Mess, W H; Vonck, K; Carrette, E; Breuer, L E M; Bernas, A; Tijhuis, A G; Boon, P

    2016-06-01

    Neuromodulation is a field of science, medicine, and bioengineering that encompasses implantable and non-implantable technologies for the purpose of improving quality of life and functioning of humans. Brain neuromodulation involves different neurostimulation techniques: transcranial magnetic stimulation (TMS), transcranial direct current stimulation (tDCS), vagus nerve stimulation (VNS), and deep brain stimulation (DBS), which are being used both to study their effects on cognitive brain functions and to treat neuropsychiatric disorders. The mechanisms of action of neurostimulation remain incompletely understood. Insight into the technical basis of neurostimulation might be a first step towards a more profound understanding of these mechanisms, which might lead to improved clinical outcome and therapeutic potential. This review provides an overview of the technical basis of neurostimulation focusing on the equipment, the present understanding of induced electric fields, and the stimulation protocols. The review is written from a technical perspective aimed at supporting the use of neurostimulation in clinical practice. PMID:27021215

  12. Synchronizing two coupled chaotic neurons in external electrical stimulation using backstepping control

    International Nuclear Information System (INIS)

    Backstepping design is a recursive procedure that combines the choice of a Lyapunov function with the design of a controller. In this paper, the backstepping control is used to synchronize two coupled chaotic neurons in external electrical stimulation. The coupled model is based on the nonlinear cable model and only one state variable can be controlled in practice. The backstepping design needs only one controller to synchronize two chaotic systems and it can be applied to a variety of chaotic systems whether they contain external excitation or not, so the two coupled chaotic neurons in external electrical stimulation can be synchronized perfectly by backstepping control. Numerical simulations demonstrate the effectiveness of this design

  13. Synchronization of FitzHugh-Nagumo neurons in external electrical stimulation via nonlinear control

    International Nuclear Information System (INIS)

    Synchronization of FitzHugh-Nagumo neural system under external electrical stimulation via the nonlinear control is investigated in this paper. Firstly, the different dynamical behavior of the nonlinear cable model based on the FitzHugh-Nagumo model responding to various external electrical stimulations is studied. Next, using the result of the analysis, a nonlinear feedback linearization control scheme and an adaptive control strategy are designed to synchronization two neurons. Computer simulations are provided to verify the efficiency of the designed synchronization schemes

  14. 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.

  15. Synchronization of FitzHugh-Nagumo neurons in external electrical stimulation via nonlinear control

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jiang [School of Electrical and Automation Engineering, Tianjin University, Tianjin 300072 (China)]. E-mail: jiangwang@tju.edu.cn; Zhang Ting [School of Electrical and Automation Engineering, Tianjin University, Tianjin 300072 (China); Deng Bin [School of Electrical and Automation Engineering, Tianjin University, Tianjin 300072 (China)

    2007-01-15

    Synchronization of FitzHugh-Nagumo neural system under external electrical stimulation via the nonlinear control is investigated in this paper. Firstly, the different dynamical behavior of the nonlinear cable model based on the FitzHugh-Nagumo model responding to various external electrical stimulations is studied. Next, using the result of the analysis, a nonlinear feedback linearization control scheme and an adaptive control strategy are designed to synchronization two neurons. Computer simulations are provided to verify the efficiency of the designed synchronization schemes.

  16. Synchronizing two coupled chaotic neurons in external electrical stimulation using backstepping control

    Energy Technology Data Exchange (ETDEWEB)

    Deng Bin [School of Electrical and Automation Engineering, Tianjin University, 300072 Tianjin (China); Wang Jiang [School of Electrical and Automation Engineering, Tianjin University, 300072 Tianjin (China)]. E-mail: jiangwang@tju.edu.cn; Fei Xiangyang [School of Electrical and Automation Engineering, Tianjin University, 300072 Tianjin (China)

    2006-07-15

    Backstepping design is a recursive procedure that combines the choice of a Lyapunov function with the design of a controller. In this paper, the backstepping control is used to synchronize two coupled chaotic neurons in external electrical stimulation. The coupled model is based on the nonlinear cable model and only one state variable can be controlled in practice. The backstepping design needs only one controller to synchronize two chaotic systems and it can be applied to a variety of chaotic systems whether they contain external excitation or not, so the two coupled chaotic neurons in external electrical stimulation can be synchronized perfectly by backstepping control. Numerical simulations demonstrate the effectiveness of this design.

  17. Electrical stimulation of cerebellar fastigial nucleus protects rat brain, in vitro, from staurosporine-induced apoptosis.

    Science.gov (United States)

    Zhou, P; Qian, L; Glickstein, S B; Golanov, E V; Pickel, V M; Reis, D J

    2001-10-01

    Electrical stimulation of the cerebellar fastigial nucleus (FN) elicits a prolonged ( approximately 10 days) and substantial (50-80%) protection against ischemic and excitotoxic injuries. The mechanism(s) of protection are unknown. We investigated whether FN stimulation directly protects brain cells against apoptotic cell death in an in vitro rat brain slice culture model. Rats were electrically stimulated in FN or, as control, the cerebellar dentate nucleus (DN). Coronal slices through the forebrain were explanted, exposed to staurosporine, harvested, and analyzed for caspase-3 activity by a fluorescence assay. FN, but not DN, stimulation significantly reduced staurosporine-induced caspase-3 activity by 39 +/- 7% at 3 h, 31 +/- 3% at 6 h and 26 +/- 4% at 10 h of incubation. Immunocytochemistry revealed FN-specific reductions in activated caspase-3 mainly in glial-like cells throughout the forebrain. FN stimulation also results in a 56.5% reduction in cytochrome c release upon staurosporine incubation. We conclude that neuroprotection elicited from FN stimulation can directly modify the sensitivity of brain cells to apoptotic stimuli and thereby suppress staurosporine induced apoptosis in adult rat brain slices. This model indicates that neuroprotection can be studied in vitro and provides new insight into the potential role of glial cells in ischemic protection of neurons induced by FN stimulation. PMID:11677261

  18. Using evoked EMG as a synthetic force sensor of isometric electrically stimulated muscle.

    Science.gov (United States)

    Erfanian, A; Chizeck, H J; Hashemi, R M

    1998-02-01

    A method for the estimation of the force generated by electrically stimulated muscle during isometric contraction is developed here. It is based upon measurements of the evoked electromyogram (EMG) [EEMG] signal. Muscle stimulation is provided to the quadriceps muscle of a paralyzed human subject using percutaneous intramuscular electrodes, and EEMG signals are collected using surface electrodes. Through the use of novel signal acquisition and processing techniques, as well as a mathematical model that reflects both the excitation and activation phenomena involved in isometric muscle force generation, accurate prediction of stimulated muscle forces is obtained for large time horizons. This approach yields synthetic muscle force estimates for both unfatigued and fatigued states of the stimulated muscle. In addition, a method is developed that accomplishes automatic recalibration of the model to account for day-to-day changes in pickup electrode mounting as well as other factors contributing to EEMG gain variations. It is demonstrated that the use of the measured EEMG as the input to a predictive model of muscle torque generation is superior to the use of the electrical stimulation signal as the model input. This is because the measured EEMG signal captures all of the neural excitation, whereas stimulation-to-torque models only reflect that portion of the neural excitation that results directly from stimulation. The time-varying properties of the excitation process cannot be captured by existing stimulation-to-torque models, but they are tracked by the EEMG-to-torque models that are developed here. This work represents a promising approach to the real-time estimation of stimulated muscle force in functional neuromuscular stimulation applications. PMID:9473842

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

    Directory of Open Access Journals (Sweden)

    Caroline Garcia Forlim

    Full Text Available 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.

  20. 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.

  1. 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. PMID:27006422

  2. 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. PMID:26926578

  3. Treatment of Early-stage Adhesive Shoulder Periarthritis with Transcutaneous Electric Stimulation on Acupoints

    Institute of Scientific and Technical Information of China (English)

    徐晓; 方剑乔; 张奕; 刘侃卓; 韩丑萍

    2006-01-01

    目的:观察经皮穴位电刺激对粘连前期肩关节周围炎的治疗作用.方法:采用大样本、多中心、随机化等循证医学研究方法,对163例粘连前期肩关节周围炎患者分别进行经皮穴位电刺激治疗和电针治疗,观察经皮穴位电刺激对粘连前期肩周炎的治疗作用及与电针治疗的效应比较.结果与结论:经皮穴位电刺激对粘连前期肩周炎的总有效率达到96.59%,与电针比较无明显差异;该疗法不仅具有明显的止痛效应,对肩关节活动障碍也有明显的改善作用.经皮穴位电刺激为治疗肩周炎有效、简便的疗法.%To observe the therapeutic effects of transcutaneous electric acupoint stimulation on early-stage adhesive shoulder periarthritis. Methods:by using the research approach of evidence-based medicine such as multi-center,large sample and randomization,the 163 cases of early-stage adhesive shoulder periarthritis were treated with transcutaneous electric point stimulation and electric acupuncture respectively to observe the therapeutic effect of transcutaneous electric acupoint stimulation and compare its effect with electric acupuncture.Results and Conclusion:The total effective rate of transcutaneous electric point stimulation on early-stage adhesive shoulder periarthritis reached 96.5%,showing no significant difference with the electric acupuncture group;the transcutaneous electric acupoint stimulation could not only relieve pain,but also improve the shoulder joint movement. As a result,the transcutaneous electric acupoint stimulation is an easy and more effective therapy for shoulder periarthritis.

  4. 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.

  5. 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

  6. 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...

  7. Peripheral electrical stimulation in Alzheimer's disease - A randomized controlled trial on cognition and behavior

    NARCIS (Netherlands)

    van Dijk, KRA; Scheltens, P; Luijpen, MW; Sergeant, JA; Scherder, EJA

    2005-01-01

    In a number of studies, peripheral electrical nerve stimulation has been applied to Alzheimer's disease (AD) patients who lived in a nursing home. Improvements were observed in memory, verbal fluency, affective behavior, activities of daily living and on the rest-activity rhythm and pupillary light

  8. 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…

  9. Negative expectations facilitate mechanical hyperalgesia after high-frequency electrical stimulation of human skin

    NARCIS (Netherlands)

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

    2014-01-01

    BACKGROUND: High-frequency electrical stimulation (HFS) of human skin induces not only an increased pain sensitivity in the conditioning area but also an increased pain sensitivity to mechanical punctate stimuli in the non-conditioned surrounding skin area. The aim of the present study was to invest

  10. 42 CFR 414.232 - Special payment rules for transcutaneous electrical nerve stimulators (TENS).

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Special payment rules for transcutaneous electrical nerve stimulators (TENS). 414.232 Section 414.232 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICARE PROGRAM PAYMENT FOR PART B MEDICAL AND...

  11. 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

  12. Electrically stimulated free-flap graciloplasty for urinary sphincter reconstruction : a new surgical procedure

    NARCIS (Netherlands)

    van Aalst, V C; Werker, P M; Stremel, R W; Perez Abadia, G A; Petty, G D; Heilman, S J; Palacio, M M; Kon, M; Tobin, G R; Barker, J H

    1998-01-01

    In electrically stimulated (dynamic) graciloplasty for urinary incontinence, the gracilis muscle is transposed into the pelvis, and the distal part is used to reconstruct a neosphincter. Clinical outcomes using this technique have been disappointing due to stricture of the urethra caused by ischemia

  13. 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...

  14. 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 a...... 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...... (interquartile range, 20–29), respectively. During the 7-day study period, the volume of the quadriceps muscle on the control thigh decreased by 16% (4–21%, p = .03) corresponding to a rate of 2.3% per day. The volume of the stimulated muscle decreased by 20% (3–25%, p = .04) corresponding to a rate of 2.9% per...

  15. [Real-time Gait Training System with Embedded Functional Electrical Stimulation].

    Science.gov (United States)

    Gu, Linyan; Ruan, Zhaomin; Jia, Guifeng; Xla, Jing; Qiu, Lijian; Wu, Changwang; Jin, Xiaoqing; Ning, Gangmin

    2015-07-01

    To solve the problem that mostly gait analysis is independent from the treatment, this work proposes a system that integrates the functions of gait training and assessment for foot drop treatment. The system uses a set of sensors to collect gait parameters and designes multi-mode functional electrical stimulators as actuator. Body area network technology is introduced to coordinate the data communication and execution of the sensors and stimulators, synchronize the gait analysis and foot drop treatment. Bluetooth 4.0 is applied to low the power consumption of the system. The system realizes the synchronization of treatment and gait analysis. It is able to acquire and analyze the dynamic parameters of ankle, knee and hip in real-time, and treat patients by guiding functional electrical stimulation delivery to the specific body locations of patients. PMID:26665943

  16. Efficacy of bilateral pallidotomy.

    Science.gov (United States)

    Kim, R; Alterman, R; Kelly, P J; Fazzini, E; Eidelberg, D; Beric, A; Sterio, D

    1997-03-15

    Unilateral pallidotomy is a safe and effective treatment for medically refractory bradykinetic Parkinson's disease, especially in those patients with levodopa-induced dyskinesia and severe on-off fluctuations. The efficacy of bilateral pallidotomy is less certain. The authors completed 11 of 12 attempted bilateral pallidotomies among 150 patients undergoing pallidotomy at New York University. In all but one patient, the pallidotomies were separated by at least 9 months. Patients were selected for bilateral pallidotomy if they exhibited bilateral rigidity, bradykinesia, or levodopa-induced dyskinesia prior to treatment or if they exhibited disease progression contralateral to their previously treated side. The Unified Parkinson's Disease Rating Scale (UPDRS) and timed upper-extremity tasks of the Core Assessment Protocol for Intracerebral Transplantation (CAPIT) were administered to all 12 patients in the "off" state (12 hours without receiving medications) preoperatively and again at 6 and 12 months after each procedure. The median UPDRS and contralateral CAPIT scores improved 60% following the initial procedure (p = 0.008, Wilcoxon rank sums test). The second pallidotomy generated only an additional 10% improvement in the UPDRS and CAPIT scores ipsilateral to the original procedure (p = 0.05). Worsened speech was observed in two cases. In the 12th case, total speech arrest was noted during test stimulation. Speech returned within minutes after stimulation was halted. Lesioning was not performed. These results indicate that bilateral pallidotomy has a narrow therapeutic window. Motor improvement ipsilateral to the first lesion leaves little room for further improvement from the second lesion and the risk of speech deficit is greatly enhanced. Chronic pallidal stimulation contralateral to a previously successful pallidotomy may prove to be a safer alternative for the subset of patients who require bilateral procedures. PMID:15096015

  17. Neuromuscular electrical stimulation and testosterone did not influence heterotopic ossification size after spinal cord injury: A case series.

    Science.gov (United States)

    Moore, Pamela D; Gorgey, Ashraf S; Wade, Rodney C; Khalil, Refka E; Lavis, Timothy D; Khan, Rehan; Adler, Robert A

    2016-07-16

    Neuromuscular electrical stimulation (NMES) and testosterone replacement therapy (TRT) are effective rehabilitation strategies to attenuate muscle atrophy and evoke hypertrophy in persons with spinal cord injury (SCI). However both interventions might increase heterotopic ossification (HO) size in SCI patients. We present the results of two men with chronic traumatic motor complete SCI who also had pre-existing HO and participated in a study investigating the effects of TRT or TRT plus NMES resistance training (RT) on body composition. The 49-year-old male, Subject A, has unilateral HO in his right thigh. The 31-year-old male, Subject B, has bilateral HO in both thighs. Both participants wore transdermal testosterone patches (4-6 mg/d) daily for 16 wk. Subject A also underwent progressive NMES-RT twice weekly for 16 wk. Magnetic resonance imaging scans were acquired prior to and post intervention. Cross-sectional areas (CSA) of the whole thigh and knee extensor skeletal muscles, femoral bone, and HO were measured. In Subject A (NMES-RT + TRT), the whole thigh skeletal muscle CSA increased by 10%, the knee extensor CSA increased by 17%, and the HO + femoral bone CSA did not change. In Subject B (TRT), the whole thigh skeletal muscle CSA increased by 13% in the right thigh and 6% in the left thigh. The knee extensor CSA increased by 7% in the right thigh and did not change in the left thigh. The femoral bone and HO CSAs in both thighs did not change. Both the TRT and NMES-RT + TRT protocols evoked muscle hypertrophy without stimulating the growth of pre-existing HO. PMID:27458592

  18. 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.

  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. Development of network-based multichannel neuromuscular electrical stimulation system for stroke rehabilitation.

    Science.gov (United States)

    Qu, Hongen; Xie, Yongji; Liu, Xiaoxuan; He, Xin; Hao, Manzhao; Bao, Yong; Xie, Qing; Lan, Ning

    2016-01-01

    Neuromuscular electrical stimulation (NMES) is a promising assistive technology for stroke rehabilitation. Here we present the design and development of a multimuscle stimulation system as an emerging therapy for people with paretic stroke. A network-based multichannel NMES system was integrated based on dual bus architecture of communication and an H-bridge current regulator with a power booster. The structure of the system was a body area network embedded with multiple stimulators and a communication protocol of controlled area network to transmit muscle stimulation parameter information to individual stimulators. A graphical user interface was designed to allow clinicians to specify temporal patterns and muscle stimulation parameters. We completed and tested a prototype of the hardware and communication software modules of the multichannel NMES system. The prototype system was first verified in nondisabled subjects for safety, and then tested in subjects with stroke for feasibility with assisting multijoint movements. Results showed that synergistic stimulation of multiple muscles in subjects with stroke improved performance of multijoint movements with more natural velocity profiles at elbow and shoulder and reduced acromion excursion due to compensatory trunk rotation. The network-based NMES system may provide an innovative solution that allows more physiological activation of multiple muscles in multijoint task training for patients with stroke. PMID:27149687

  1. Electrical stimulation of the auditory nerve: direct current measurement in vivo.

    Science.gov (United States)

    Huang, C Q; Shepherd, R K; Carter, P M; Seligman, P M; Tabor, B

    1999-04-01

    Neural prostheses use charge recovery mechanisms to ensure the electrical stimulus is charge balanced. Nucleus cochlear implants short all stimulating electrodes between pulses in order to achieve charge balance, resulting in a small residual direct current (DC). In the present study we sought to characterize the variation of this residual DC with different charge recovery mechanisms, stimulation modes, and stimulation parameters, and by modeling, to gain insight into the underlying mechanisms. In an acute study with anaesthetised guinea pigs, DC was measured in four platinum intracochlear electrodes stimulated using a Nucleus C124M cochlear implant at moderate to high pulse rates (1200-14,500 pulses/s) and stimulus intensities (0.2-1.75 mA at 26-200 microseconds/phase). Both monopolar and bipolar stimulation modes were used, and the effects of shorting or combining a capacitor with shorting for charge recovery were investigated. Residual DC increased as a function of stimulus rate, stimulus intensity, and pulse width. DC was lower for monopolar than bipolar stimulation, and lower still with capacitively coupled monopolar stimulation. Our model suggests that residual DC is a consequence of Faradaic reactions which allow charge to leak through the electrode tissue interface. Such reactions and charge leakage are still present when capacitors are used to achieve charge recovery, but anodic and cathodic reactions are balanced in such a way that the net charge leakage is zero. PMID:10217884

  2. Commentary: physical approaches for the treatment of epilepsy: electrical and magnetic stimulation and cooling.

    Science.gov (United States)

    Löscher, Wolfgang; Cole, Andrew J; McLean, Michael J

    2009-04-01

    Physical approaches for the treatment of epilepsy currently under study or development include electrical or magnetic brain stimulators and cooling devices, each of which may be implanted or applied externally. Some devices may stimulate peripheral structures, whereas others may be implanted directly into the brain. Stimulation may be delivered chronically, intermittently, or in response to either manual activation or computer-based detection of events of interest. Physical approaches may therefore ultimately be appropriate for seizure prophylaxis by causing a modification of the underlying substrate, presumably with a reduction in the intrinsic excitability of cerebral structures, or for seizure termination, by interfering with the spontaneous discharge of pathological neuronal networks. Clinical trials of device-based therapies are difficult due to ethical issues surrounding device implantation, problems with blinding, potential carryover effects that may occur in crossover designs if substrate modification occurs, and subject heterogeneity. Unresolved issues in the development of physical treatments include optimization of stimulation parameters, identification of the optimal volume of brain to be stimulated, development of adequate power supplies to stimulate the necessary areas, and a determination that stimulation itself does not promote epileptogenesis or adverse long-term effects on normal brain function. PMID:19332318

  3. Comparison of skin sensory thresholds using pre-programmed or single-frequency transcutaneous electrical nerve stimulation

    Science.gov (United States)

    Kang, Jong Ho

    2015-01-01

    [Purpose] The purpose of the present study was to compare the sensory thresholds of healthy subjects using pre-programmed or single-frequency transcutaneous electrical nerve stimulation. [Subjects] Ninety healthy adult subjects were randomly assigned to pre-programmed or single-frequency stimulation groups, each consisting of 45 participants. [Methods] Sensory thresholds were measured in the participants’ forearms using von Frey filaments before and after pre-programmed or single-frequency transcutaneous electrical nerve stimulation, and the result in values were analyzed. [Results] Significant increases in sensory threshold after stimulation were observed in both groups. However, there were no significant differences between the two groups in sensory thresholds after stimulation or in the magnitude of threshold increases following stimulation. [Conclusion] Our results show that there are no differences between sensory threshold increases induced by pre-programmed and single-frequency transcutaneous electrical nerve stimulation. PMID:26834358

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

    Science.gov (United States)

    Adeyemi, Kazeem Dauda; Sazili, Awis Qurni

    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 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. PMID:25049973

  5. Classification of methods in transcranial Electrical Stimulation (tES) and evolving strategy from historical approaches to contemporary innovations

    OpenAIRE

    Guleyupoglu, Berkan; Schestatsky, Pedro; Edwards, Dylan; Fregni, Felipe; Bikson, Marom

    2013-01-01

    Transcranial Electrical Stimulation (tES) encompasses all methods of non-invasive current application to the brain used in research and clinical practice. We present the first comprehensive and technical review, explaining the evolution of tES in both terminology and dosage over the past 100 years of research to present day. Current transcranial Pulsed Current Stimulation (tPCS) approaches such as Cranial Electrotherapy Stimulation (CES) descended from Electrosleep (ES) through Cranial Electr...

  6. 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.

  7. Electrical stimulation of the parabrachial nucleus induces reanimation from isoflurane general anesthesia.

    Science.gov (United States)

    Muindi, Fanuel; Kenny, Jonathan D; Taylor, Norman E; Solt, Ken; Wilson, Matthew A; Brown, Emery N; Van Dort, Christa J

    2016-06-01

    Clinically, emergence from general anesthesia is viewed as a passive process where anesthetics are discontinued at the end of surgery and anesthesiologists wait for the drugs to wear off. The mechanisms involved in emergence are not well understood and there are currently no drugs that can actively reverse the state of general anesthesia. An emerging hypothesis states that brain regions that control arousal become active during emergence and are a key part of the return to wakefulness. In this study, we tested the hypothesis that electrical activation of the glutamatergic parabrachial nucleus (PBN) in the brainstem is sufficient to induce reanimation (active emergence) during continuous isoflurane general anesthesia. Using c-Fos immunohistochemistry as a marker of neural activity, we first show a selective increase in active neurons in the PBN during passive emergence from isoflurane anesthesia. We then electrically stimulated the PBN to assess whether it is sufficient to induce reanimation from isoflurane general anesthesia. Stimulation induced behavioral arousal and restoration of the righting reflex during continuous isoflurane general anesthesia. In contrast, stimulation of the nearby central inferior colliculus (CIC) did not restore the righting reflex. Spectral analysis of the electroencephalogram (EEG) revealed that stimulation produced a significant decrease in EEG delta power during PBN stimulation. The results are consistent with the hypothesis that the PBN provides critical arousal input during emergence from isoflurane anesthesia. PMID:26971629

  8. 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

    Objective. 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. Approach. 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. Main results. 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. Significance. 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.

  9. 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.

  10. 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.

  11. 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. PMID:20382974

  12. Coupled chemo-electro-mechanical finite element simulation of hydrogels: II. Electrical stimulation

    International Nuclear Information System (INIS)

    Certain polyelectrolyte gels are distinguished by a large swelling or bending capability under the influence of external physical, chemical or electrical stimuli. In this paper we investigate the mechanisms occurring in polyelectrolyte gels due to externally applied electric fields. By applying a coupled chemo-electro-mechanical model which is extended and predestined for electrical stimulation, we describe the concentrations and the electric potential in both the gel and the solution as well as the locally different swelling and shrinking in the gel. The local change of geometry is formulated by a local osmotic pressure difference between the gel and the solution next to the gel phase. In addition to this effect, the change of the local gel domain leads to a local variation of the concentration of bound groups and thus to a change of the local concentrations of mobile ions. As the focus of the presented work we demonstrate the superiority of the fully coupled chemo-electro-mechanical description compared to the previously developed one-way chemo-electric to mechanical coupled model. Finally, by a qualitative comparison with experimental results, the validity of the fully coupled chemo-electro-mechanical model for electrical stimulation is demonstrated

  13. In situ electric fields causing electro-stimulation from conductor contact of charged human

    International Nuclear Information System (INIS)

    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. (authors)

  14. 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.

  15. Infrared neural stimulation (INS) inhibits electrically evoked neural responses in the deaf white cat

    Science.gov (United States)

    Richter, Claus-Peter; Rajguru, Suhrud M.; Robinson, Alan; Young, Hunter K.

    2014-03-01

    Infrared neural stimulation (INS) has been used in the past to evoke neural activity from hearing and partially deaf animals. All the responses were excitatory. In Aplysia californica, Duke and coworkers demonstrated that INS also inhibits neural responses [1], which similar observations were made in the vestibular system [2, 3]. In deaf white cats that have cochleae with largely reduced spiral ganglion neuron counts and a significant degeneration of the organ of Corti, no cochlear compound action potentials could be observed during INS alone. However, the combined electrical and optical stimulation demonstrated inhibitory responses during irradiation with infrared light.

  16. Electrical stimulation of the hypothalamic nucleus paraventricularis mimics the effects of light on pineal melatonin synthesis

    International Nuclear Information System (INIS)

    In an attempt to clarify further the role of the hypothalamic paraventricular nuclei (PVN) in the control of pineal function, the effects of 2 min electrical stimulation of these nuclei were investigated in acutely blinded, adult, male Sprague-Dawley rats. Pineal serotonin-N-acetyltransferase (NAT) activity, melatonin content and catecholamine levels were measured by means of radio-enzymatic, radioimmunoassay and high-performance liquid-chromatography methods, respectively. All three pineal parameters underwent significant declines following brief PVN stimulation during the night time. These observations lend credence to the view that the neural pathways transmitting light information to the sympathetic innervation controlling pineal melatonin synthesis. 22 references, 1 figure

  17. 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

  18. Use of tricalcium phosphate or electrical stimulation to enhance the bone-porous implant interface.

    Science.gov (United States)

    Berry, J L; Geiger, J M; Moran, J M; Skraba, J S; Greenwald, A S

    1986-01-01

    Implant stabilization by biologic ingrowth into a porous surface offers a durable method of prosthetic fixation. These systems, however, lack the immediate stability offered by the use of acrylic bone cement. The interface strength of porous coated Co--Cr--Mo in a canine model does not approach that of acrylic bone cement until two weeks postoperatively. It is expected that this would be a minimum time period in clinical applications. Both chemical and electrical means have been advocated as methods to affect tissue ingrowth. A study using a canine model was undertaken to determine tissue ingrowth rates utilizing examples of these two methods: (1) impregnation of the porous structures with tricalcium phosphate powder (TCP); or (2) the application of an electrical stimulator to the implant with the implant itself serving as the cathode. Ten implants were coated with TCP, two each at weekly intervals from 1 to 5 weeks. Plain porous rods were likewise implanted, serving as the controls. While histology did reveal a slightly more dense bony structure, the interface bond strength was not affected by TCP. Electrical stimulation of the implant was similarly investigated with an additional time period of 10 weeks. Compared to the controls, the electrically stimulated implants reveal no statistically demonstratable difference in interface strength. Histologic specimens indicate larger areas of calcification than are observed in the controls. PMID:3949824

  19. A Comparative Study of the Effects of Magnetic Stimulation and Electric Stimulation on Peripheral Nerve Injury in Rat

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The influence of pulsed magnetic stimulation (MS) on the sciatic nerve injury was investigated. Thirty rats were divided into three groups equally: MS group (A), electric stimulation (ES) group (B) and the control group (C). The MS and ES were applied immediately after the first 10 min of the sciatic nerve crush. Sciatic function index (SFI), toe spreading reflex (TSR), muscular weight and volume were measured after the experiment. The TSR of in the groups A and B occurred at 4th day while in the control group it occurs at 10th day. There was statistically significant difference in SFI between groups A and B (P<0.01). The weight and volume of the gastrocnemius muscle were statistically greater in the groups A and B than in the control group (P<0.01). The effect of MS was similar to that of ES. It was suggested that the application of MS immediately after the nerve injury might have an important clinical value as it can accelerate functional recovery and prevent or minimize muscle atrophy. The technique is easily to operate, non-invasion, painless and permits tolerance of high intensity output to be used.

  20. Differential responsiveness of the right parahippocampal region to electrical stimulation in fixed human brains: Implications for historical surgical stimulation studies?

    Science.gov (United States)

    Rouleau, Nicolas; Persinger, Michael A

    2016-07-01

    If structure dictates function within the living human brain, then the persistence of specific responses to weak electric currents in fixed, deceased brains could reflect "hardwired" properties. Different key structures from the left and right hemispheres of brains that had been fixed for over 20years with ethanol-formalin-acetic acid were stimulated with either 1-Hz, 7-Hz, 10-Hz, 20-Hz, or 30-Hz, sine-wave, square-wave, or pulsed currents while needle-recorded quantitative electroencephalographic responses were obtained. Differential responses occurred only within the right hippocampus and parahippocampal gyrus. The right hippocampus displayed frequency-independent increases in gamma power relative to the left hemispheric homologue. The parahippocampal region responded exclusively to 7-Hz pulsed currents with wideband (8-30Hz) power. These profiles are consistent with dynamic connections associated with memory and consciousness and may partially explain the interactions resultant of pulse type and hemisphere for experiential elicitations during the golden age of surgical stimulations. The results also indicate that there may be an essential "hardwiring" within the human brain that is maintained for decades when it is fixed appropriately. PMID:27208828

  1. 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.

  2. Comparison of two models of electric neuro-stimulation and consequences for the design of retinal prostheses

    OpenAIRE

    Schmid, Erich W.

    2007-01-01

    Two simple mathematical models of electric neuro-stimulation are derived and discussed. It is found that the common injected-charge model is less realistic than a model, in which a latency period, which follows after a short electric pulse, plays a role as important as the electric pulse. A stimulation signal is proposed that takes advantage of these findings and calls for experimental testing.

  3. The application of preoperative functional MRI in neurosurgical treatment of intraoperative electrical stimulation for gliomas involving motor areas at 3 T

    International Nuclear Information System (INIS)

    Objective: To assess the value of preoperative blood oxygen level dependent (BOLD) 3 T functional magnetic resonance imaging (fMRI) to identify motor cortical areas in neurosurgical treatment of intraoperative electrical stimulation for gliomas involving motor areas. Methods: The study included 26 consecutive preoperative BOLD-fMRI sessions in patients with brain gliomas in or near senorimotor cortices. The bilateral hand movement fMRI paradigm was preformed in all patients. The BOLD data were analyzed by the workstation (Leonardo Syngo 2003A, Siemens)to obtain the BOLD-fMRI images, which were used to guide the preoperative neurosurgical planning. With guidance of preoperative mapping, all patients received microsurgery under anaesthesia retaining consciousness using intraoperative motor functional brain mapping with the method of direct electrical stimulations. The brain lesions were removed as far as possible in the case of eloquent areas preservation. The preoperative and postoperative KPS of all patients were operated to evaluate the state of patients. Results: The preoperative mappings of the hand area on primary sensorimotor cortex using BOLD-fMRI were obtained successfully in twenty-three of twenty-six patients. Under anaesthesia retaining consciousness, the primary motor area was monitored by the method of direct electrical stimulations with the guidance of preoperative BOLD-fMRI. There was good correlation between preoperative fMRI findings and intraoperative cortical stimulation. Furthermore, the preoperative mappings could make up for the un-monitored areas during operative cortical stimulation. For the 21 patients of the pre-KPS from 80.0 to 90.0, the pre-KPS and post-KPS are 85.7 and 95.2 respectively, and for the 5 patients of the pre-KPS from 40. 0 to 70.0, the pre-KPS and post-KPS are 68.0 and 90.0 respectively. Conclusion: The preoperative mapping of the hand area on primary sensorimotor cortex using BOLD-fMRI could non-invasively localize the

  4. Alternating current electrical stimulation enhanced chemotherapy: a novel strategy to bypass multidrug resistance in tumor cells

    International Nuclear Information System (INIS)

    Tumor burden can be pharmacologically controlled by inhibiting cell division and by direct, specific toxicity to the cancerous tissue. Unfortunately, tumors often develop intrinsic pharmacoresistance mediated by specialized drug extrusion mechanisms such as P-glycoprotein. As a consequence, malignant cells may become insensitive to various anti-cancer drugs. Recent studies have shown that low intensity very low frequency electrical stimulation by alternating current (AC) reduces the proliferation of different tumor cell lines by a mechanism affecting potassium channels while at intermediate frequencies interfere with cytoskeletal mechanisms of cell division. The aim of the present study is to test the hypothesis that permeability of several MDR1 over-expressing tumor cell lines to the chemotherapic agent doxorubicin is enhanced by low frequency, low intensity AC stimulation. We grew human and rodent cells (C6, HT-1080, H-1299, SKOV-3 and PC-3) which over-expressed MDR1 in 24-well Petri dishes equipped with an array of stainless steel electrodes connected to a computer via a programmable I/O board. We used a dedicated program to generate and monitor the electrical stimulation protocol. Parallel cultures were exposed for 3 hours to increasing concentrations (1, 2, 4, and 8 μM) of doxorubicin following stimulation to 50 Hz AC (7.5 μA) or MDR1 inhibitor XR9576. Cell viability was assessed by determination of adenylate kinase (AK) release. The relationship between MDR1 expression and the intracellular accumulation of doxorubicin as well as the cellular distribution of MDR1 was investigated by computerized image analysis immunohistochemistry and Western blot techniques. By the use of a variety of tumor cell lines, we show that low frequency, low intensity AC stimulation enhances chemotherapeutic efficacy. This effect was due to an altered expression of intrinsic cellular drug resistance mechanisms. Immunohistochemical, Western blot and fluorescence analysis revealed

  5. Alternating current electrical stimulation enhanced chemotherapy: a novel strategy to bypass multidrug resistance in tumor cells

    Directory of Open Access Journals (Sweden)

    Dini Gabriele

    2006-03-01

    Full Text Available Abstract Background Tumor burden can be pharmacologically controlled by inhibiting cell division and by direct, specific toxicity to the cancerous tissue. Unfortunately, tumors often develop intrinsic pharmacoresistance mediated by specialized drug extrusion mechanisms such as P-glycoprotein. As a consequence, malignant cells may become insensitive to various anti-cancer drugs. Recent studies have shown that low intensity very low frequency electrical stimulation by alternating current (AC reduces the proliferation of different tumor cell lines by a mechanism affecting potassium channels while at intermediate frequencies interfere with cytoskeletal mechanisms of cell division. The aim of the present study is to test the hypothesis that permeability of several MDR1 over-expressing tumor cell lines to the chemotherapic agent doxorubicin is enhanced by low frequency, low intensity AC stimulation. Methods We grew human and rodent cells (C6, HT-1080, H-1299, SKOV-3 and PC-3 which over-expressed MDR1 in 24-well Petri dishes equipped with an array of stainless steel electrodes connected to a computer via a programmable I/O board. We used a dedicated program to generate and monitor the electrical stimulation protocol. Parallel cultures were exposed for 3 hours to increasing concentrations (1, 2, 4, and 8 μM of doxorubicin following stimulation to 50 Hz AC (7.5 μA or MDR1 inhibitor XR9576. Cell viability was assessed by determination of adenylate kinase (AK release. The relationship between MDR1 expression and the intracellular accumulation of doxorubicin as well as the cellular distribution of MDR1 was investigated by computerized image analysis immunohistochemistry and Western blot techniques. Results By the use of a variety of tumor cell lines, we show that low frequency, low intensity AC stimulation enhances chemotherapeutic efficacy. This effect was due to an altered expression of intrinsic cellular drug resistance mechanisms. Immunohistochemical

  6. 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...... changes at the level of the z-lines were investigated by transmission electron microscopy. Blood samples were collected for measurement of creatine kinase activity, and muscle soreness was assessed in the days following stimulation. The biopsies from the stimulated muscle revealed macrophage infiltration...... of damage at the myofiber and sarcomere levels. These data support the hypothesis that muscle damage at the level of the sarcomere can be induced without lengthening muscle contractions....

  7. Experimental model for transcutaneous electrical nerve stimulation on ischemic random skin flap in rats

    Directory of Open Access Journals (Sweden)

    Liebano Richard Eloin

    2003-01-01

    Full Text Available The objective of this paper was to develop an experimental model to be used in the study of Transcutaneous Electrical Nerve Stimulation (TENS on viability of random skin flap in rats. The sample was 15 Wistar-EPM rats. The random skin flap measured 10x4 cm and a plastic barrier was placed between the flap and the donnor site. The animals were submited to TENS for 1 hour immediately after the surgery and on the two subsequent days. On the seventh postoperative day, the percentage of necrotic area was measured and calculated. The experimental model proved to be reliable to be used in the study of effects of Transcutaneous Electrical Nerve Stimulation in random skin flap in rats.

  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. PMID:26210898

  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 the......% 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...

  10. 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...... pain (rho = -0.13, P = .09, and rho = -1.2, P = .4, respectively. PERSPECTIVE: Although preoperative electrical nociceptive stimulation may predict patients at risk of high-intensity acute pain after other surgical procedures, this was not the case in groin hernia repair patients receiving concomitant...

  11. Prefrontal electrical stimulation in nondepressed reduces levels of reported negative affects from daily stressors

    Directory of Open Access Journals (Sweden)

    Adelaide H Austin

    2016-03-01

    Full Text Available Negative emotional responses to the daily life stresses have cumulative effects which, in turn, impose wide-ranging negative constraints on emotional well being and neurocognitive performance (Kalueff et al, 2007, Charles et al, 2013, Nadler et al, 2010. Crucial cognitive functions such as memory and problem solving, as well more short term emotional responses (e.g., anticipation of- and response to- monetary rewards or losses are influenced by mood. The negative impact of these behavioural responses is felt at the individual level, but it also imposes major economic burden on modern healthcare systems. Although much research have been undertaken to understand the underlying mechanisms of depressed mood and design efficient treatment pathways, comparatively little was done to characterize mood modulations that remain within the boundaries of a healthy mental functioning. In one placebo-controlled experiments, we applied daily prefrontal transcranial Direct Current Stimulation (tDCS at five points in time, and found reliable improvements on self-reported mood evaluation. We replicated this finding in an independent double-blinded placebo-controlled experiment and showed that stimulation over a shorter period of time (3 days is sufficient to create detectable mood improvements. Taken together, our data show that repeated bilateral prefrontal tDCS can reduce psychological distress in nondepressed individuals.

  12. 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 (< 1.4 ms). In separate studies, we compared the latency of the responses to electrical stimulation of the corticospinal tract in the relaxed muscle with that in the contracting muscle. The latency was the same in the......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...

  13. Evoked Electromyography-Based Closed-Loop Torque Control in Functional Electrical Stimulation

    OpenAIRE

    Zhang, Qin; Hayashibe, Mitsuhiro; Azevedo Coste, Christine

    2013-01-01

    This work proposed a closed-loop torque control strategy of functional electrical stimulation (FES) with the aim of obtaining an accurate, safe and robust FES system. Generally, FES control systems are faced with the challenge of how to deal with time-variant muscle dynamics due to physiological and biochemical factors (such as fatigue). The degraded muscle force needs to be compensated in order to ensure the accuracy of the motion restored by FES. Another challenge concerns the fact that imp...

  14. EFFECT OF TRAINING WITH NEUROMUSCULAR ELECTRICAL STIMULATION ON ELBOW FLEXION STRENGTH

    OpenAIRE

    Holcomb, William R.

    2006-01-01

    Neuromuscular electrical stimulation (NMES) may be used to prevent strength loss associated with post-surgical immobilization. Most studies testing the effectiveness of NMES have trained the knee extensors. The purpose of this investigation was to test the effectiveness of NMES when training the elbow flexors. Twenty-four students were randomly assigned to one of three groups: NMES training, isometric training or control. Testing and training were completed using a Biodex™ dynamometer. After ...

  15. Electrical stimulation of sympathetic nerves increases the concentration of cyclic AMP in rat pineal gland.

    OpenAIRE

    Heydorn, W E; Frazer, A; Weiss, B.

    1981-01-01

    Electrical stimulation of the superior cervical ganglia causes a rapid increase in the concentration of cyclic AMP in the pineal gland of rats. This effect is dependent upon the frequency, voltage, and duration of the stimulus and is markedly potentiated by pretreating the animals with desmethylimipramine. The increase in cyclic AMP is blocked by prior treatment of the rats with reserpine, bretylium, or propanolol but not with phentolamine. These results provide direct evidence that electrica...

  16. Microsoft Kinect-Based Artificial Perception System for Control of Functional Electrical Stimulation Assisted Grasping

    OpenAIRE

    Matija Štrbac; Slobodan Kočović; Marko Marković; Popović, Dejan B.

    2014-01-01

    We present a computer vision algorithm that incorporates a heuristic model which mimics a biological control system for the estimation of control signals used in functional electrical stimulation (FES) assisted grasping. The developed processing software acquires the data from Microsoft Kinect camera and implements real-time hand tracking and object analysis. This information can be used to identify temporal synchrony and spatial synergies modalities for FES control. Therefore, the algorithm ...

  17. Robotics combined with electrical stimulation: hybrid support of arm and hand for functional training after stroke

    OpenAIRE

    Westerveld, A.J.

    2014-01-01

    Reach, grasp and release is part of many functional movements. Graying of society leads to more stroke victims and fewer health care professionals. Technology might be a solution to support certain rehabilitation therapies in future health care. Robotic systems have been developed for support of arm and hand movements and functional electrical stimulation (FES) has been applied to activate arm and hand muscles. Therapeutic effects of both techniques have been shown similar to conventional the...

  18. The Effect of Mirror Therapy Integrating Functional Electrical Stimulation on the Gait of Stroke Patients

    OpenAIRE

    Ji, Sang-Goo; Cha, Hyun-Gyu; Kim, Myoung-Kwon; Lee, Chang-Ryeol

    2014-01-01

    [Purpose] The aim of the present study was to examine whether mirror therapy in conjunction with FES in stroke patients can improve gait ability. [Subjects] This study was conducted with 30 subjects who were diagnosed with hemiparesis due to stroke. [Methods] Experimental group I contained 10 subjects who received mirror therapy in conjunction with functional electrical stimulation, experimental group II contained 10 subjects who received mirror therapy, and the control group contained 10 sub...

  19. The Synergic Effects of Mirror Therapy and Neuromuscular Electrical Stimulation for Hand Function in Stroke Patients

    OpenAIRE

    Yun, Gi Jeong; Chun, Min Ho; Park, Ji Young; Kim, Bo Ryun

    2011-01-01

    Objective To investigate the synergic effects of mirror therapy and neuromuscular electrical stimulation (NMES) for hand function in stroke patients. Method Sixty patients with hemiparesis after stroke were included (41 males and 19 females, average age 63.3 years). Twenty patients had NMES applied and simultaneously underwent mirror therapy. Twenty patients had NMES applied only, and twenty patients underwent mirror therapy only. Each treatment was done five days per week, 30 minutes per day...

  20. Role of transcutaneous electric nerve stimulation in the management of trigeminal neuralgia

    OpenAIRE

    Sanju Singla; Vikram Prabhakar; Rajan Kumar Singla

    2011-01-01

    Background: Trigeminal neuralgia typically involves nerves supplying teeth, jaws and face of older females. Though the etiology is usually obscure, different treatment modalities have been tried for it viz. medicinal treatment, injection alcohol, peripheral neurectomy, rhizotomy, and microvascular decompression etc. Transcutaneous electric nerve stimulation (TENS) is an emerging and promising option for management of such patients. Aims and Design: The present study was designed with an aim t...

  1. Remodelling of the contractile apparatus of striated muscle stimulated electrically in a shortened position.

    OpenAIRE

    Jakubiec-Puka, A; Carraro, U

    1991-01-01

    The aim of this study was to examine reorganisation of the contractile apparatus during adaptation to function when the length of a muscle is decreased. The rat soleus muscle was maintained in a shortened position and simultaneously stimulated electrically at a low frequency for 1-45 h. This experimental model decreased the length of the muscle and made the contractile apparatus irregular. The length of the sarcomeres decreased and became variable. The Z-line appeared wavy or fragmented. Foci...

  2. Changes in Hyolaryngeal Movement and Swallowing Function After Neuromuscular Electrical Stimulation in Patients With Dysphagia

    OpenAIRE

    Lee, Hoo Young; Hong, Ji Seong; Lee, Kil Chan; Shin, Yoon-Kyum; Cho, Sung-Rae

    2015-01-01

    Objective To investigate immediate changes in hyolaryngeal movement and swallowing function after a cycle of neuromuscular electrical stimulation (NMES) on both submental and throat regions and submental placement alone in patients with dysphagia. Methods Fifteen patients with dysphagia were recruited. First, videofluoroscopic swallowing study (VFSS) was performed before NMES. All patients thereafter received a cycle of NMES by 2 methods of electrode placement: 1) both submental and throat re...

  3. Chaotic synchronization with gap junction of multi-neurons in external electrical stimulation

    International Nuclear Information System (INIS)

    The synchronization of n(n 3) neurons coupled with gap junction in external electrical stimulation is investigated. In this paper, the coupled model is established on the basis of nonlinear cable model, and then the relation between coupling strength of the gap junction and the synchronization is discussed in detail. The sufficient condition of complete synchronization is attained from rigorous mathematical derivation. The synchronizations of periodic neurons and chaotic neurons are studied respectively

  4. Chaotic synchronization of neurons coupled with gap junction under external electrical stimulation

    International Nuclear Information System (INIS)

    The synchronization of neurons coupled with gap junction in the condition of external electrical stimulation is investigated. In this paper, the coupled model is established on the basis of the nonlinear cable equation, and then the relation of coupling strength of the gap junction and the synchronization is discussed in detail. The sufficient condition of complete synchronization is obtained from rigorous mathematical derivation. The synchronizations of periodic neurons and chaotic neurons are studied, respectively

  5. 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 ...

  6. Evaluation of Functional Electrical Stimulation to Assist Cycling in Four Adolescents with Spastic Cerebral Palsy

    OpenAIRE

    McRae, Calum G. A.; Lee, Samuel C. K.; Ann Tokay Harrington

    2012-01-01

    Introduction. Adolescents with cerebral palsy (CP) often have difficulty participating in exercise at intensities necessary to improve cardiovascular fitness. Functional electrical stimulation- (FES-) assisted cycling is proposed as a form of exercise for adolescents with CP. The aims of this paper were to adapt methods and assess the feasibility of applying FES cycling technology in adolescents with CP, determine methods of performing cycling tests in adolescents with CP, and evaluate the im...

  7. Haemodynamic performance of neuromuscular electrical stimulation (NMES) during recovery from total hip arthroplasty

    OpenAIRE

    Broderick, Barry J.; Breathnach, Oisin; Condon, Finbarr; Masterson, Eric; ÓLaighin, Gearóid

    2013-01-01

    Background Patients post total hip arthroplasty (THA) remain at high risk of developing Deep Vein Thrombosis (DVT) during the recovery period following surgery despite the availability of effective pharmacological and mechanical prophylactic methods. The use of calf muscle neuromuscular electrical stimulation (NMES) during the hospitalised recovery period on this patient group may be effective at preventing DVT. However, the haemodynamic effectiveness and comfort characteristics of NMES in po...

  8. Differences in end-point force trajectories elicited by electrical stimulation of individual human calf muscles

    OpenAIRE

    Giordano, S B; Segal, R L; Abelew, T A

    2009-01-01

    The purpose of this study was to investigate the end-point force trajectories of the fibularis longus (FIB), lateral gastrocnemius (LG) and medial gastrocnemius (MG) muscles. Most information about individual muscle function has come from studies which use models based on electromyographic (EMG) recordings. In this study (N=20 subjects) we used electrical stimulation (20Hz) to elicit activity in individual muscles, recorded the end-point forces at the foot and verified the selectivity of stim...

  9. Transcutaneous electric acupoint stimulation at Jiaji points reduce abdominal pain after colonoscopy: a randomized controlled trial

    OpenAIRE

    Chen, Yanqing; Wu, Weilan; Yao, Yusheng; Yang, Yang; Zhao, Qiuyan; Qiu, Liangcheng

    2015-01-01

    Background: Transcutaneous electric acupoint stimulation (TEAS) at Jiaji acupuncture points has therapeutic potential for relieving viscera pain and opioid-related side effects. This prospective, randomized, triple-blinded, placebo-controlled trial was to investigate the efficacy of TEAS on abdominal pain after colonoscopy. Methods: Consecutive outpatients with American Society of Anesthesiologists (ASA) physical status I or II underwent selective colonoscopy were randomly assigned into two g...

  10. Low-Frequency Electrical Stimulation Attenuates Muscle Atrophy in CKD—A Potential Treatment Strategy

    OpenAIRE

    Hu, Li; Klein, Janet D.; Hassounah, Faten; Cai, Hui; Zhang, Cong; Xu, Ping; Wang, Xiaonan H.

    2014-01-01

    Effective therapeutic strategies to treat CKD-induced muscle atrophy are urgently needed. Low-frequency electrical stimulation (LFES) may be effective in preventing muscle atrophy, because LFES is an acupuncture technique that mimics resistance exercise by inducing muscle contraction. To test this hypothesis, we treated 5/6-nephrectomized mice (CKD mice) and control mice with LFES for 15 days. LFES prevented soleus and extensor digitorum longus muscle weight loss and loss of hind-limb muscle ...

  11. Microcurrent Electrical Neuromuscular Stimulation Facilitates Regeneration of Injured Skeletal Muscle in Mice

    OpenAIRE

    Fujiya, Hiroto; Ogura, Yuji; Ohno, Yoshitaka; Goto, Ayumi; Nakamura, Ayane; Ohashi, Kazuya; Uematsu, Daiki; Aoki, Haruhito; Musha, Haruki; Goto, Katsumasa

    2015-01-01

    Conservative therapies, mainly resting care for the damaged muscle, are generally used as a treatment for skeletal muscle injuries (such as muscle fragmentation). Several past studies reported that microcurrent electrical neuromuscular stimulation (MENS) facilitates a repair of injured soft tissues and shortens the recovery period. However, the effects of MENS on the regeneration in injured skeletal muscle are still unclear. The purpose of this study was to investigate the effect of MENS on t...

  12. 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.

  13. A simulation study of harmonics regeneration in noise reduction for electric and acoustic stimulation

    OpenAIRE

    Hu, Yi

    2010-01-01

    Recent research results show that combined electric and acoustic stimulation (EAS) significantly improves speech recognition in noise, and it is generally established that access to the improved F0 representation of target speech, along with the glimpse cues, provide the EAS benefits. Under noisy listening conditions, noise signals degrade these important cues by introducing undesired temporal-frequency components and corrupting harmonics structure. In this study, the potential of combining n...

  14. Gastric Electrical Stimulation Reduces Visceral Sensitivity to Gastric Distention in Healthy Canines

    OpenAIRE

    Chen, Ji-Hong; Song, Geng-Qing; Yin, Jieyun; Yan SUN; Chen, Jiande DZ

    2010-01-01

    The aim of this study was to investigate the effects and mechanisms of gastric electrical stimulation (GES) on proximal stomach distention-induced visceral sensitivity. Isobaric gastric distention was performed using a barostat system in 8 normal and 6 vagotomized dogs and animal behaviors were noted and graded. The normal dogs were studied in 4 sessions: control (no GES), short pulse GES, long pulse GES, and dual-pulse GES, and the vagotomized dogs were studied in three sessions: control (no...

  15. Feasibility of functional electrical stimulated cycling in subjects with spinal cord injury: an energetic assessment

    OpenAIRE

    Perret, Claudio; Berry, Helen; Hunt, Kenneth J; Donaldson, Nick; Kakebeeke, Tanja H

    2010-01-01

    Objective: To determine the functional electrical stimulated (FES) cycling volume necessary to reach the recommended weekly exercise caloric expenditure of 1000–2200 kcal in FES-trained subjects with paraplegia.Subjects: Eight (7 males, 1 female) FES-trained subjects with traumatic motor and sensory complete paraplegia (AIS A, lesion level between Th3 and Th9) of at least 3 years duration were included.Methods: Subjects performed an FES-training session at the highest workload they were able ...

  16. Radio electric asymmetric brain stimulation in the treatment of behavioral and psychiatric symptoms in Alzheimer disease

    OpenAIRE

    Mannu P; Rinaldi S; Fontani V; Castagna A

    2011-01-01

    Piero Mannu1, Salvatore Rinaldi1,2, Vania Fontani1, Alessandro Castagna11Rinaldi Fontani Institute, Department of Neuro Psycho Physio Pathology, Florence, Italy; 2Medical School of Occupational Medicine, University of Florence, Florence, ItalyPurpose: Behavioral and psychiatric symptoms of dementia (BPSD) are common in Alzheimer's disease (AD) and disrupt the effective management of AD patients. The present study explores the use of radio electric asymmetric brain stimulation (REAC) i...

  17. COMBINED EFFECTS OF FAST TREADMILL WALKING AND FUNCTIONAL ELECTRICAL STIMULATION ON POST-STROKE GAIT

    OpenAIRE

    Kesar, Trisha M.; Reisman, Darcy S.; Perumal, Ramu; Jancosko, Angela M.; Higginson, Jill S.; Rudolph, Katherine S.; Binder-Macleod, Stuart A

    2010-01-01

    Gait dysfunctions are highly prevalent in individuals post-stroke and affect multiple lower extremity joints. Recent evidence suggests that treadmill walking at faster than self-selected speeds can help improve post-stroke gait impairments. Also, the combination of functional electrical stimulation (FES) and treadmill training has emerged as a promising post-stroke gait rehabilitation intervention. However, the differential effects of combining FES with treadmill walking at the fast versus a ...

  18. Saccade Modulation by Optical and Electrical Stimulation in the Macaque Frontal Eye Field

    OpenAIRE

    Ohayon, Shay; Grimaldi, Piercesare; Schweers, Nicole; Tsao, Doris Y.

    2013-01-01

    Recent studies have demonstrated that strong neural modulations can be evoked with optogenetic stimulation in macaque motor cortex without observing any evoked movements (Han et al., 2009, 2011; Diester et al., 2011). It remains unclear why such perturbations do not generate movements and if conditions exist under which they may evoke movements. In this study, we examine the effects of five optogenetic constructs in the macaque frontal eye field and use electrical microstimulation to assess w...

  19. Chaotic synchronization of neurons coupled with gap junction under external electrical stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Jiang Wang E-mail: jiangwang@tju.edu.cn; Bin Deng; Tsang, K.M

    2004-10-01

    The synchronization of neurons coupled with gap junction in the condition of external electrical stimulation is investigated. In this paper, the coupled model is established on the basis of the nonlinear cable equation, and then the relation of coupling strength of the gap junction and the synchronization is discussed in detail. The sufficient condition of complete synchronization is obtained from rigorous mathematical derivation. The synchronizations of periodic neurons and chaotic neurons are studied, respectively.

  20. Chaotic synchronization with gap junction of multi-neurons in external electrical stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Deng Bin [School of Electrical and Automation Engineering, Tianjin University, 300072 Tianjin (China); Wang Jiang [School of Electrical and Automation Engineering, Tianjin University, 300072 Tianjin (China)] e-mail: jiangwang@tju.edu.cn; Fei Xiangyang [School of Electrical and Automation Engineering, Tianjin University, 300072 Tianjin (China)

    2005-09-01

    The synchronization of n(n 3) neurons coupled with gap junction in external electrical stimulation is investigated. In this paper, the coupled model is established on the basis of nonlinear cable model, and then the relation between coupling strength of the gap junction and the synchronization is discussed in detail. The sufficient condition of complete synchronization is attained from rigorous mathematical derivation. The synchronizations of periodic neurons and chaotic neurons are studied respectively.

  1. Portable EMG devices, Biofeedback and Contingent Electrical Stimulation applications in Bruxism

    OpenAIRE

    Castrillon, Eduardo

    2016-01-01

    Portable EMG devices, Biofeedback and Contingent Electrical Stimulation applications in BruxismEduardo Enrique, Castrillon Watanabe, DDS, MSc, PhDSection of Orofacial Pain and Jaw Function, Department of Dentistry, Aarhus University, Aarhus, Denmark; Scandinavian Center for Orofacial NeuroscienceSummary: 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 d...

  2. 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. PMID:23182636

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

    Science.gov (United States)

    Ganji, Yasaman; Li, Qian; Quabius, Elgar Susanne; Böttner, Martina; Selhuber-Unkel, Christine; Kasra, Mehran

    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. PMID:26652343

  4. Pulse electrical arc stimulator based on single-electrode for active exercise in tail-suspension rat

    Institute of Scientific and Technical Information of China (English)

    孙联文; 谢添; 樊瑜波; 张晓薇; 孙瑶; 杨肖

    2008-01-01

    To make rat do active exercise to counteract bone loss in the rat tail-suspension model, a pulse electrical stimulator based on single-electrode with a low-current and a high-voltage was designed. The stimulator was controlled by SCM (single chip micyoco) that could accurately control the stimulation duration and the interval between stimulations, and cease the operation after the recorded number of stimulation had reached the value set by the program. With the help of posture estimation part, the device would operate intelligently by determining whether to stimulate or not, depending on the posture of rat’s limb. Software was developed to make operator control the stimulator using computer, save the experiment data and print the report. In practical experiment, the voltaic arc is generated by the stimulator, and impacted on the rat’s thenar. This induced pain to the rat and the rat would actively contract its hindlimb to evade the pain, so active exercise was carried out. The tail-suspension rats were trained twice every day for 14 d. At the 0 and 14th day, bone mineral density of rat femurs was determined by dual energy X-ray absorptiometry (DXA). The results show that the active exercise stimulated by the pulse electrical arc stimulator can attenuate weightlessness-induced bone loss, and this device is a convenient steady performance electrical stimulator that can surely induce rat’s hindlimb to do active exercise.

  5. Surface electrical stimulation for foot drop: Control aspects and walking performance

    Directory of Open Access Journals (Sweden)

    Stein Richard B.

    2008-01-01

    Full Text Available Use of electrical stimulation to correct foot drop in hemiplegia was proposed over 40 years ago. Recently, improved control strategies have been developed and implemented in commercially available devices. In this article we review the control methods that have been used and present some results from a multi-center clinical trial. A foot-drop stimulator improves the gait pattern and results in an immediate increase in walking speed. In this sense it acts like an ankle-foot orthosis and this immediate increase will be referred to as an orthotic effect. Prolonged use of a foot drop stimulator over a period of months results in further, large increases in walking speed both with the stimulator on and off. Evidence indicates that a part of this increase results from daily use that strengthens residual cortico-spinal connections. Therefore the improvement over time will be referred to as a therapeutic effect. We found that people with non-progressive and progressive conditions of the central nervous system have an orthotic benefit, as well as a therapeutic up to 3 months of use. In generally non-progressive conditions such as stroke, further therapeutic increases are seen up to at least 11 months of use. In disorders such as multiple sclerosis, the progression of the disease eventually overcomes the early therapeutic effects. In conclusion, many individuals can benefit from commercially available foot-drop stimulators with improved control strategies and cosmetic design.

  6. Electrical stimulation directs engineered cardiac tissue to an age-matched native phenotype

    Directory of Open Access Journals (Sweden)

    Richard A Lasher

    2012-07-01

    Full Text Available Quantifying structural features of native myocardium in engineered tissue is essential for creating functional tissue that can serve as a surrogate for in vitro testing or the eventual replacement of diseased or injured myocardium. We applied three-dimensional confocal imaging and image analysis to quantitatively describe the features of native and engineered cardiac tissue. Quantitative analysis methods were developed and applied to test the hypothesis that environmental cues direct engineered tissue toward a phenotype resembling that of age-matched native myocardium. The analytical approach was applied to engineered cardiac tissue with and without the application of electrical stimulation as well as to age-matched and adult native tissue. Individual myocytes were segmented from confocal image stacks and assigned a coordinate system from which measures of cell geometry and connexin-43 spatial distribution were calculated. The data were collected from 9 nonstimulated and 12 electrically stimulated engineered tissue constructs and 5 postnatal day 12 and 7 adult hearts. The myocyte volume fraction was nearly double in stimulated engineered tissue compared to nonstimulated engineered tissue (0.34 ± 0.14 vs 0.18 ± 0.06 but less than half of the native postnatal day 12 (0.90 ± 0.06 and adult (0.91 ± 0.04 myocardium. The myocytes under electrical stimulation were more elongated compared to nonstimulated myocytes and exhibited similar lengths, widths, and heights as in age-matched myocardium. Furthermore, the percentage of connexin-43-positive membrane staining was similar in the electrically stimulated, postnatal day 12, and adult myocytes, whereas it was significantly lower in the nonstimulated myocytes. Connexin-43 was found to be primarily located at cell ends for adult myocytes and irregularly but densely clustered over the membranes of nonstimulated, stimulated, and postnatal day 12 myocytes. These findings support our hypothesis and reveal

  7. Bilateral dacryoadenitis

    Directory of Open Access Journals (Sweden)

    Charlotte Derr

    2012-01-01

    Full Text Available Acute dacryoadenitis is an uncommon condition that involves inflammation of the lacrimal gland. In rare instances, dacryoadenitis may be bilateral. A delay in proper treatment of an otherwise simple case of dacryoadenitis may lead to significant soft tissue morbidity such as cellulitis, lacrimal gland abscess, or orbital abscess. We report the case of a 24-year-old male who presented to the emergency department with acute bilateral dacryoadenitis. The patient′s symptoms did not respond to oral antibiotics and he subsequently required admission for intravenous antibiotics. During his hospitalization the patient had diagnostic testing to try to determine the etiology for his symptoms. The unique aspects of managing a case of bilateral dacryoadenitis as well as treatment recommendations are discussed in this case report.

  8. 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. PMID:26913137

  9. Neuromuscular electrical stimulation improves exercise tolerance in chronic obstructive pulmonary disease patients with better preserved fat-free mass

    Directory of Open Access Journals (Sweden)

    Lara Maris Nápolis

    2011-01-01

    Full Text Available BACKGROUND: High-frequency neuromuscular electrical stimulation increases exercise tolerance in patients with advanced chronic obstructive pulmonary disease (COPD patients. However, it is conceivable that its benefits are more prominent in patients with better-preserved peripheral muscle function and structure. OBJECTIVE: To investigate the effects of high-frequency neuromuscular electrical stimulation in COPD patients with better-preserved peripheral muscle function. Design: Prospective and cross-over study. METHODS: Thirty COPD patients were randomly assigned to either home-based, high-frequency neuromuscular electrical stimulation or sham stimulation for six weeks. The training intensity was adjusted according to each subject's tolerance. Fat-free mass, isometric strength, six-minute walking distance and time to exercise intolerance (Tlim were assessed. RESULTS: Thirteen (46.4% patients responded to high-frequency neuromuscular electrical stimulation; that is, they had a post/pre Δ Tlim >10% after stimulation (unimproved after sham stimulation. Responders had a higher baseline fat-free mass and six-minute walking distance than their seventeen (53.6% non-responding counterparts. Responders trained at higher stimulation intensities; their mean amplitude of stimulation during training was significantly related to their fat-free mass (r = 0.65; p<0.01. Logistic regression revealed that fat-free mass was the single independent predictor of Tlim improvement (odds ratio [95% CI] = 1.15 [1.04-1.26]; p<0.05. CONCLUSIONS: We conclude that high-frequency neuromuscular electrical stimulation improved the exercise capacity of COPD patients with better-preserved fat-free mass because they tolerated higher training stimulus levels. These data suggest that early training with high-frequency neuromuscular electrical stimulation before tissue wasting begins might enhance exercise tolerance in patients with less advanced COPD.

  10. The assessment of a novel electrical stimulation waveform recently introduced for the treatment of overactive bladder

    International Nuclear Information System (INIS)

    Transdermal amplitude modulated signal (TAMS) is a novel electrical stimulus which has been recently introduced for the treatment of overactive bladder (OAB) syndrome. It has been suggested that it has advantages over conventional waveforms by providing more effective penetration of the skin to enhance the efficacy of therapy. As there is no literature which supports this, we performed this study to evaluate potential advantages of the TAMS signal for electrical stimulation of subcutaneous nerves as compared to conventional stimuli. The stimuli were applied on forearms of ten healthy volunteers and electrical parameters of stimuli and sensation measurements were recorded. None of the recorded electrical parameters showed significant differences (paired t-test p ≥ 0.250) between the TAMS and conventional waveforms. Similarly, the mean sensation recorded at motor threshold level and at 50% of maximal motor response level showed no differences (paired t-test p = 0.242 and p = 0.687 respectively). It is unlikely, based on the results of this study, that TAMS provides any enhancement of the efficacy of conventional stimuli. We would recommend that further studies are carried out to clearly demonstrate in man what, if any, advantages the TAMS waveform has over conventional stimulation before it is widely deployed into clinical practice. (paper)

  11. Meridian electrical potential response to acupuncture stimulation between operator and subject.

    Science.gov (United States)

    Lee, Yongheum; Kim, Soobyung; Son, Taeyoon; Kang, Dongyeon; Jung, Byungjo

    2010-12-01

    The human body has a symmetric structure and maintains a physiological balance through the harmony of yin and yang. One of the fundamental principles of acupuncture is that unbalanced or abnormal bioenergetic conditions on the left and right meridians may be restored to a balanced, normal condition by acupuncture therapy. In this study, the electrical potential along the stomach meridian was measured to investigate the bioenergy consensus between the operator and subject during acupuncture stimulation, and the acupuncture response on opposite meridians was investigated by comparing the electric potential on the left and right stomach meridian during stimulation of the left side stomach meridian-36. When meridian electrical potential was simultaneously measured in both the operator and subject, opposite polarities were observed, which might indicate the transfer of bioenergy between operator and subject. In addition, the meridian electrical potentials of the subjects' left and right stomach meridians were also always of opposite polarity and presented three different signal patterns, which might have represented the condition of the associated meridian. PMID:21185539

  12. Binaural Unmasking of Multi-channel Stimuli in Bilateral Cochlear Implant Users

    OpenAIRE

    Van Deun, Lieselot; Van Wieringen, Astrid; Francart, Tom; Büchner, Andreas; Lenarz, Thomas; Wouters, Jan

    2011-01-01

    Previous work suggests that bilateral cochlear implant users are sensitive to interaural cues if experimental speech processors are used to preserve accurate interaural information in the electrical stimulation pattern. Binaural unmasking occurs in adults and children when an interaural delay is applied to the envelope of a high-rate pulse train. Nevertheless, for speech perception, binaural unmasking benefits have not been demonstrated consistently, even with coordinated stimulation at both ...

  13. Directing lineage specification of human mesenchymal stem cells by decoupling electrical stimulation and physical patterning on unmodified graphene

    Science.gov (United States)

    Balikov, Daniel A.; Fang, Brian; Chun, Young Wook; Crowder, Spencer W.; Prasai, Dhiraj; Lee, Jung Bok; Bolotin, Kiril I.; Sung, Hak-Joon

    2016-07-01

    The organization and composition of the extracellular matrix (ECM) have been shown to impact the propagation of electrical signals in multiple tissue types. To date, many studies with electroactive biomaterial substrates have relied upon passive electrical stimulation of the ionic media to affect cell behavior. However, development of cell culture systems in which stimulation can be directly applied to the material - thereby isolating the signal to the cell-material interface and cell-cell contracts - would provide a more physiologically-relevant paradigm for investigating how electrical cues modulate lineage-specific stem cell differentiation. In the present study, we have employed unmodified, directly-stimulated, (un)patterned graphene as a cell culture substrate to investigate how extrinsic electrical cycling influences the differentiation of naïve human mesenchymal stem cells (hMSCs) without the bias of exogenous biochemicals. We first demonstrated that cyclic stimulation does not deteriorate the cell culture media or result in cytotoxic pH, which are critical experiments for correct interpretation of changes in cell behavior. We then measured how the expression of osteogenic and neurogenic lineage-specific markers were altered simply by exposure to electrical stimulation and/or physical patterns. Expression of the early osteogenic transcription factor RUNX2 was increased by electrical stimulation on all graphene substrates, but the mature marker osteopontin was only modulated when stimulation was combined with physical patterns. In contrast, the expression of the neurogenic markers MAP2 and β3-tubulin were enhanced in all electrical stimulation conditions, and were less responsive to the presence of patterns. These data indicate that specific combinations of non-biological inputs - material type, electrical stimulation, physical patterns - can regulate hMSC lineage specification. This study represents a substantial step in understanding how the interplay of

  14. Effect of early treatment with transcutaneous electrical diaphragmatic stimulation (TEDS on pulmonary inflammation induced by bleomycin

    Directory of Open Access Journals (Sweden)

    Laisa A. Santos

    2013-12-01

    Full Text Available 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 B (intratracheally, 2.5 mg/kg (B; and a group treated with B and electric stimulation (B + TEDS. After the B instillation, the electrical stimulation was applied for 7 days, for a duration of 20 minutes. Lung fragments were histologically processed with hematoxylin and eosin (HE and 8-isoprostane-PGF2α (8-iso-PGF2α. The density of the alveolar area was determined by planimetry, the inflammatory profile was defined by the number of cells, and the level of oxidative stress in the pulmonary tissue was evaluated by 8-iso-PGF2α. For statistical analysis of the data, the Shapiro-Wilk test was used, followed by a one-way ANOVA with the post-hoc Bonferroni test (p≤0.05. RESULTS : The B group exhibited a significant reduction in the area density, and the acute treatment with B + TEDS prevented this reduction. There were increased numbers of fibroblasts, leukocytes, and macrophages in the B group, as well as increased lipid peroxidation, which was observed only in this group. CONCLUSION : B promoted a reduction in the alveolar density area, thereby inducing the inflammatory process and increasing the production of free radicals. These effects were minimized by the application of TEDS at the initial treatment stage.

  15. Modelling extracellular electrical stimulation: III. Derivation and interpretation of neural tissue equations

    Science.gov (United States)

    Meffin, Hamish; Tahayori, Bahman; Sergeev, Evgeni N.; Mareels, Iven M. Y.; Grayden, David B.; Burkitt, Anthony N.

    2014-12-01

    Objective. A common approach in modelling extracellular electrical stimulation is to represent neural tissue by a volume conductor when calculating the activating function as the driving term in a cable equation for the membrane potential. This approach ignores the cellular composition of tissue, including the neurites and their combined effect on the extracellular potential. This has a number of undesirable consequences. First, the two natural and equally valid choices of boundary conditions for the cable equation (i.e. using either voltage or current) lead to two mutually inconsistent predictions of the membrane potential. Second, the spatio-temporal distribution of the extracellular potential can be strongly affected by the combined cellular composition of the tissue. In this paper, we develop a mean field volume conductor theory to overcome these shortcomings of available models. Approach. This method connects the microscopic properties of the constituent fibres to the macroscopic electrical properties of the tissue by introducing an admittivity kernel for the neural tissue that is non-local, non-instantaneous and anisotropic. This generalizes the usual tissue conductivity. A class of bidomain models that is mathematically equivalent to this class of self-consistent volume conductor models is also presented. The bidomain models are computationally convenient for simulating the activation map of neural tissue using numerical methods such as finite element analysis. Main results. The theory is first developed for tissue composed of identical, parallel fibres and then extended to general neural tissues composed of mixtures of neurites with different and arbitrary orientations, arrangements and properties. Equations describing the extracellular and membrane potential for the longitudinal and transverse modes of stimulation are derived. Significance. The theory complements our earlier work, which developed extensions to cable theory for the micro-scale equations of

  16. The epileptic amygdala: Toward the development of a neural prosthesis by temporally coded electrical stimulation.

    Science.gov (United States)

    Cota, Vinícius Rosa; Drabowski, Bruna Marcela Bacellar; de Oliveira, Jasiara Carla; Moraes, Márcio Flávio Dutra

    2016-06-01

    Many patients with epilepsy do not obtain proper control of their seizures through conventional treatment. We review aspects of the pathophysiology underlying epileptic phenomena, with a special interest in the role of the amygdala, stressing the importance of hypersynchronism in both ictogenesis and epileptogenesis. We then review experimental studies on electrical stimulation of mesiotemporal epileptogenic areas, the amygdala included, as a means to treat medically refractory epilepsy. Regular high-frequency stimulation (HFS) commonly has anticonvulsant effects and sparse antiepileptogenic properties. On the other hand, HFS is related to acute and long-term increases in excitability related to direct neuronal activation, long-term potentiation, and kindling, raising concerns regarding its safety and jeopardizing in-depth understanding of its mechanisms. In turn, the safer regular low-frequency stimulation (LFS) has a robust antiepileptogenic effect, but its pro- or anticonvulsant effect seems to vary at random among studies. As an alternative, studies by our group on the development and investigation of temporally unstructured electrical stimulation applied to the amygdala have shown that nonperiodic stimulation (NPS), which is a nonstandard form of LFS, is capable of suppressing both acute and chronic spontaneous seizures. We hypothesize two noncompetitive mechanisms for the therapeutic role of amygdala in NPS, 1) a direct desynchronization of epileptic circuitry in the forebrain and brainstem and 2) an indirect desynchronization/inhibition through nucleus accumbens activation. We conclude by reintroducing the idea that hypersynchronism, rather than hyperexcitability, may be the key for epileptic phenomena and epilepsy treatment. © 2016 Wiley Periodicals, Inc. PMID:27091311

  17. Influence of S3 electrical stimulation on gastrointestinal dysfunction after spinal cord injury in rabbits

    Institute of Scientific and Technical Information of China (English)

    Bai Chunhong; Li Shuangying; An Hong

    2014-01-01

    Objective:To investigate the effect of electrical stimulation to sacral spinal nerve 3 (S3 stimulation) on gastrointestinal dysfunction after spinal cord injury (SCI).Methods:Six rabbits were taken as normal controls to record their gastrointestinal multipoint biological discharge,colon pressure and rectoanal inhibitory reflex.Electrodes were implanted into S3 in another 18 rabbits.Then the model of SCI was conducted following Fehling's method:the rabbit S3 was clamped to induce transverse injury,which was claimed by both somatosensory evoked potential and motion evoked potential.Two hours after SCI,S3 stimulation was conducted.The 18 rabbits were subdivided into 3 groups to respectively record their gastrointestinal electric activities (n=6),colon pressure (n=6),and rectum pressure (n=6).Firstly the wave frequency was fixed at 15 Hz and pulse width at 400 μs and three stimulus intensities (6 V,8 V,10 V) were tested.Then the voltage was fixed at 6 V and the pulse width changed from 200 μs,400 μs to 600 μs.The response was recorded and analyzed.The condition of defecation was also investigated.Results:After SCI,the mainly demonstrated change was dyskinesia of the single haustrum and distal colon.The rectoanal inhibitory reflex almost disappeared.S3 stimulation partly recovered the intestinal movement after denervation,promoting defecation.The proper stimulus parameters were 15 Hz,400 μs,6 V,10 s with 20 s intervals and 10 min with 10 min intervals,total 2 h.Conclusion:S3 stimulation is able to restore the intestinal movement after denervation (especially single haustrum and distal colon),which promotes defecation.

  18. Validation, reproducibility and safety of trans dermal electrical stimulation in chronic pain patients and healthy volunteers

    Directory of Open Access Journals (Sweden)

    Acosta Juan

    2010-01-01

    Full Text Available Abstract Background Surrogate pain models have been extensively tested in Normal Human Volunteers (NHV. There are few studies that examined pain models in chronic pain patients. Patients are likely to have altered pain mechanisms. It is of interest to test patient pain responses to selective pain stimuli under controlled laboratory conditions. Methods The Institutional Ethic Committee approved the study. 16 patients with chronic neuropathic radiculopathy and 16 healthy volunteers were enrolled to the study after obtaining informed consent. During electrical stimulation (150 minutes for volunteers and 75 minutes for patients the following parameters were measured every 10 minutes: Ongoing pain: Visual Analogue Scale (VAS and Numeric Rate Scale (NRS Allodynia (soft foam brush Hyperalgesia (von Frey monofilament 20 g Flare For each endpoint, the area under the curve (AUC was estimated from the start of stimulation to the end of stimulation by the trapezoidal rule. The individual AUC values for both periods were plotted to show the inter- and intra-subject variability. For each endpoint a mixed effect model was fitted with random effect subject and fixed effect visit. The estimate of intra-subject variance and the mean value were then used to estimate the sample size of a crossover study required to have a probability of 0.80 to detect a 25% change in the mean value. Analysis was done using GenStat 8th edition. Results Each endpoint achieved very good reproducibility for patients and NHV. Comparison between groups revealed trends towards: Faster habituation to painful stimuli in patients Bigger areas of hyperalgesia in patients Similar area of allodynia and flare (no statistical significance Conclusion The differences demonstrated between patients and NHVs suggest that the electrical stimulation device used here may stimulate pathways that are affected in the pathological state.

  19. Classification of methods in transcranial electrical stimulation (tES) and evolving strategy from historical approaches to contemporary innovations.

    Science.gov (United States)

    Guleyupoglu, Berkan; Schestatsky, Pedro; Edwards, Dylan; Fregni, Felipe; Bikson, Marom

    2013-10-15

    Transcranial Electrical Stimulation (tES) encompasses all methods of non-invasive current application to the brain used in research and clinical practice. We present the first comprehensive and technical review, explaining the evolution of tES in both terminology and dosage over the past 100 years of research to present day. Current transcranial Pulsed Current Stimulation (tPCS) approaches such as Cranial Electrotherapy Stimulation (CES) descended from Electrosleep (ES) through Cranial Electro-stimulation Therapy (CET), Transcerebral Electrotherapy (TCET), and NeuroElectric Therapy (NET) while others like Transcutaneous Cranial Electrical Stimulation (TCES) descended from Electroanesthesia (EA) through Limoge, and Interferential Stimulation. Prior to a contemporary resurgence in interest, variations of transcranial Direct Current Stimulation were explored intermittently, including Polarizing current, Galvanic Vestibular Stimulation (GVS), and Transcranial Micropolarization. The development of these approaches alongside Electroconvulsive Therapy (ECT) and pharmacological developments are considered. Both the roots and unique features of contemporary approaches such as transcranial Alternating Current Stimulation (tACS) and transcranial Random Noise Stimulation (tRNS) are discussed. Trends and incremental developments in electrode montage and waveform spanning decades are presented leading to the present day. Commercial devices, seminal conferences, and regulatory decisions are noted. We conclude with six rules on how increasing medical and technological sophistication may now be leveraged for broader success and adoption of tES. PMID:23954780

  20. Classification of methods in transcranial Electrical Stimulation (tES) and evolving strategy from historical approaches to contemporary innovations

    Science.gov (United States)

    Guleyupoglu, Berkan; Schestatsky, Pedro; Edwards, Dylan; Fregni, Felipe; Bikson, Marom

    2013-01-01

    Transcranial Electrical Stimulation (tES) encompasses all methods of non-invasive current application to the brain used in research and clinical practice. We present the first comprehensive and technical review, explaining the evolution of tES in both terminology and dosage over the past 100 years of research to present day. Current transcranial Pulsed Current Stimulation (tPCS) approaches such as Cranial Electrotherapy Stimulation (CES) descended from Electrosleep (ES) through Cranial Electro-stimulation Therapy (CET), Transcerebral Electrotherapy (TCET), and NeuroElectric Therapy (NET) while others like Transcutaneous Cranial Electrical Stimulation (TCES) descended from Electroanesthesia (EA) through Limoge, and Interferential Stimulation. Prior to a contemporary resurgence in interest, variations of trans-cranial Direct Current Stimulation were explored intermittently, including Polarizing current, Galvanic Vestibular Stimulation (GVS), and Transcranial Micropolarization. The development of these approaches alongside Electroconvulsive Therapy (ECT) and pharmacological developments are considered. Both the roots and unique features of contemporary approaches such as transcranial Alternating Current Stimulation (tACS) and transcranial Random Noise Stimulation (tRNS) are discussed. Trends and incremental developments in electrode montage and waveform spanning decades are presented leading to the present day. Commercial devices, seminal conferences, and regulatory decisions are noted. We conclude with six rules on how increasing medical and technological sophistication may now be leveraged for broader success and adoption of tES. PMID:23954780

  1. Evaluation of electric field distribution in electromagnetic stimulation of human femoral head.

    Science.gov (United States)

    Su, Yukun; Souffrant, Robert; Kluess, Daniel; Ellenrieder, Martin; Mittelmeier, Wolfram; van Rienen, Ursula; Bader, Rainer

    2014-12-01

    Electromagnetic stimulation is a common therapy used to support bone healing in the case of avascular necrosis of the femoral head. In the present study, we investigated a bipolar induction screw system with an integrated coil. The aim was to analyse the influence of the screw parameters on the electric field distribution in the human femoral head. In addition, three kinds of design parameters (the shape of the screw tip, position of the screw in the femoral head, and size of the screw insulation) were varied. The electric field distribution in the bone was calculated using the finite element software Comsol Multiphysics. Moreover, a validation experiment was set up for an identical bone specimen with an implanted screw. The electric potential of points inside and on the surface of the bone were measured and compared to numerical data. The electric field distribution within the bone was clearly changed by the different implant parameters. Repositioning the screw by a maximum of 10 mm and changing the insulation length by a maximum of 4 mm resulted in electric field volume changes of 16% and 7%, respectively. By comparing the results of numerical simulation with the data of the validation experiment, on average, the electric potential difference of 19% and 24% occurred when the measuring points were at a depth of approximately 5 mm within the femoral bone and directly on the surface of the femoral bone, respectively. The results of the numerical simulations underline that the electro-stimulation treatment of bone in clinical applications can be influenced by the implant parameters. PMID:25251424

  2. Frequency-place map for electrical stimulation in cochlear implants: Change over time.

    Science.gov (United States)

    Vermeire, Katrien; Landsberger, David M; Van de Heyning, Paul H; Voormolen, Maurits; Kleine Punte, Andrea; Schatzer, Reinhold; Zierhofer, Clemens

    2015-08-01

    The relationship between the place of electrical stimulation from a cochlear implant and the corresponding perceived pitch remains uncertain. Previous studies have estimated what the pitch corresponding to a particular location should be. However, perceptual verification is difficult because a subject needs both a cochlear implant and sufficient residual hearing to reliably compare electric and acoustic pitches. Additional complications can arise from the possibility that the pitch corresponding to an electrode may change as the auditory system adapts to a sound processor. In the following experiment, five subjects with normal or near-to-normal hearing in one ear and a cochlear implant with a long electrode array in the other ear were studied. Pitch matches were made between single electrode pulse trains and acoustic tones before activation of the speech processor to gain an estimate of the pitch provided by electrical stimulation at a given insertion angle without the influence of exposure to a sound processor. The pitch matches were repeated after 1, 3, 6, and 12 months of experience with the sound processor to evaluate the effect of adaptation over time. Pre-activation pitch matches were lower than would be estimated by a spiral ganglion pitch map. Deviations were largest for stimulation below 240° degrees and smallest above 480°. With experience, pitch matches shifted towards the frequency-to-electrode allocation. However, no statistically significant pitch shifts were observed over time. The likely explanation for the lack of pitch change is that the frequency-to-electrode allocations for the long electrode arrays were already similar to the pre-activation pitch matches. Minimal place pitch shifts over time suggest a minimal amount of perceptual remapping needed for the integration of electric and acoustic stimuli, which may contribute to shorter times to asymptotic performance. PMID:25840373

  3. A connectomics approach combining structural and effective connectivity assessed by intracranial electrical stimulation.

    Science.gov (United States)

    Donos, Cristian; Mălîia, Mihai Dragoş; Mîndruţă, Ioana; Popa, Irina; Ene, Mirela; Bălănescu, Bogdan; Ciurea, Ana; Barborica, Andrei

    2016-05-15

    In the context of the human brain, the term "connectivity" can refer to structural, functional or effective connectivity. Intracranial electrical stimulation is perhaps the most direct way of investigating the effective connectivity. We propose a method of mapping the effective connectivity, revealed by the electrical stimulation of brain structures, over the structural connectome (SC), obtained through diffusion spectrum imaging (DSI), to form a structural-effective connectome (SEC). A number of 24 patients with refractory epilepsy were implanted with depth electrodes for pre-surgical evaluation. Effective connectivity was assessed by analyzing the responses to single pulse electrical stimulation (SPES). Stimulation pulses having variable amplitude were applied to each pair of adjacent contacts and responses evoked by stimulation were recorded from other contacts located in other brain areas. Early responses (10-110 ms) on the stimulation-activated contacts located outside the epileptogenic zone were averaged for each patient, resulting in a patient-level physiological effective connectome (EC). The population level EC is computed by averaging the connections of the individual ECs, on a structure by structure basis. A fiber activation factor is used to weight the number of fibers connecting a pair of structures in the SC by its corresponding normalized EC value. The resulting number of effectively activated fibers describes the directional connection strength between two structures in the SEC. A physiological SEC comprising directional connections between 70 segmented brain areas in both hemispheres, was obtained by inclusion of structures outside the epileptogenic zone only. Over the entire structure set, the Spearman's correlation coefficient ρ between the number of fibers extracted from the DSI Atlas and the normalized RMS responses to SPES was ρ=0.21 (p<0.001), while Kendall's tau coefficients ranged -0.52-0.44 (p<0.05). The physiological structural

  4. Effects of electrical stimulation in early Bells palsy on facial disability index scores

    Directory of Open Access Journals (Sweden)

    P. Alakram

    2011-02-01

    Full Text Available Recovery following facial nerve palsy is variable. Physiotherapists try  to restore  function  in  patients  with  Bell’s  palsy.  The  choice  of treatment modality  depends  on  the  stage  of  the  condition.  Although limited  evidence  exists  for  the  use  of  electrical  stimulation  in  the acute  stage  of  Bell’s  palsy, some physiotherapists in South Africa have been applying this modality. This study examined the effects of electrical stimulation on functional recovery from  Bell’s palsy using the Facial Disability Index, a tool that documents recovery from the patients’ perspective. A two group pre-test post-test experimental design comprising of 16 patients with Bell’s Palsy of less than 30 days duration was utilized. Patients with a clinical diagnosis of Bell’s Palsy were systematically allocated to the control and experimental groups. Patients (n=16 were pre-tested and post-tested using the Facial Disability Index. Both groups were treated with heat, massage, exercises and given a home program. The experimental group also received electrical stimulation. The FDI of the control group improved between 17, 8% and 95, 4% with a mean of 52, 8%. The improvement in the experimental group ranged between 14, 8% and 126% with a mean of 49, 8%. Certain clinical residuals persisted in a mild form in both groups on discharge from the study.  The effects of electrical stimulation as used in this study during the acute phase of Bell’s palsy, quantified as the FDI was clinically but not statistically significant. A larger sample size, longer stimulation time or both should be investigated.

  5. Effect of high frequency transcutaneous electrical nerve stimulation on viability of random skin flap in rats

    Directory of Open Access Journals (Sweden)

    Liebano Richard Eloin

    2006-01-01

    Full Text Available PURPOSE: To determine the effect of high frequency Transcutaneous Electrical Nerve Stimulation (TENS on viability of random skin flap in rats. METHODS: The sample of this study was 75 Wistar rats. The skin flap measured 10 x 4 cm and a plastic barrier was interposed between the flap and donor site. After the operative procedure, animals of all groups were maintained anesthetized one more hour with electrodes positioned in the base of the flap and submitted to treatment according of their respective group. This procedure was repeated on the two subsequent days. G1: sham stimulation (control, G2: TENS (f = 80 Hz and I = 5 mA, G3: TENS (f = 80 Hz and I = 10 mA, G4: TENS (f = 80 Hz and I = 15 mA, G5: TENS (f = 80 Hz and I = 20 mA. RESULTS: The average percentage of necrotic area was 43,11, 34,65, 49,44, 23,52, 45,10 in groups 1, 2, 3, 4 and 5 respectively. CONCLUSION: The amplitude of 15 mA presented a lower necrotic area than control group and Transcutaneous Electrical Nerve Stimulation was efficient in increasing the random skin flap viability.

  6. Muscle twitch responses for shaping the multi-pad electrode for functional electrical stimulation

    Directory of Open Access Journals (Sweden)

    Malešević Nebojša

    2010-01-01

    Full Text Available In this paper we present a method for optimization of multi-pad electrode spatial selectivity during transcutaneous Functional Electrical Stimulation (FES of hand. The presented method is based on measurement of individual muscle twitch responses during low frequency electrical stimulation via pads within multi-pad electrode. Twitch responses are recorded by Micro-Electro-Mechanical Systems (MEMS accelerometers. The aim of this methodology is to substitute bulky sensors, torque sensors and goniometers, in multi-pad electrode optimization algorithm with smaller and lighter sensors; therefore making multi-pad stimulation suitable for daily use. Additionally we present method for minimizing number of MEMS accelerometers, which relies on characteristic waveforms of joint acceleration during wrist or fingers flexion/extension. These signals can be used to train Artificial Neural Network (ANN to distinguish between different waveform classes and define correlation of each pad and activated muscle beneath. Results presented in this paper show high agreement of goniometers based classification and accelerometers based classification. As for classification with minimized number of sensors (one accelerometer our ANN backed algorithm achieved high degree of accurate classification in intra-subject testing, but lower performance in inter-subject testing.

  7. Electric pulse stimulation of cultured murine muscle cells reproduces gene expression changes of trained mouse muscle.

    Directory of Open Access Journals (Sweden)

    Nathalie Burch

    Full Text Available Adequate levels of physical activity are at the center of a healthy lifestyle. However, the molecular mechanisms that mediate the beneficial effects of exercise remain enigmatic. This gap in knowledge is caused by the lack of an amenable experimental model system. Therefore, we optimized electric pulse stimulation of muscle cells to closely recapitulate the plastic changes in gene expression observed in a trained skeletal muscle. The exact experimental conditions were established using the peroxisome proliferator-activated receptor gamma coactivator 1alpha (PGC-1alpha as a marker for an endurance-trained muscle fiber. We subsequently compared the changes in the relative expression of metabolic and myofibrillar genes in the muscle cell system with those observed in mouse muscle in vivo following either an acute or repeated bouts of treadmill exercise. Importantly, in electrically stimulated C2C12 mouse muscle cells, the qualitative transcriptional adaptations were almost identical to those in trained muscle, but differ from the acute effects of exercise on muscle gene expression. In addition, significant alterations in the expression of myofibrillar proteins indicate that this stimulation could be used to modulate the fiber-type of muscle cells in culture. Our data thus describe an experimental cell culture model for the study of at least some of the transcriptional aspects of skeletal muscle adaptation to physical activity. This system will be useful for the study of the molecular mechanisms that regulate exercise adaptation in muscle.

  8. Updates on gastric electrical stimulation to treat obesity: Systematic review and future perspectives

    Institute of Scientific and Technical Information of China (English)

    Ryan; Cha; Jacques; Marescaux; Michele; Diana

    2014-01-01

    AIM: To evaluate the current state-of-the-art of gastric electrical stimulation to treat obesity. METHODS: Systematic reviews of all studies have been conducted to evaluate the effect of different types of gastric electrical stimulation(GES) on obesity.RESULTS: Thirty-one studies consisting of a total of 33 different trials were included in the systematic review for data analysis. Weight loss was achieved in most studies, especially during the first 12 mo, but only very few studies had a follow-up period longer than 1 year. Among those that had a longer follow-up period, many were from the Transcend(Implantable Gastric Stimulation) device group and maintained significant weight loss. Other significant results included changes in appetite/satiety, gastric emptying rate, blood pressure and neurohormone levels or biochemical markers such as ghrelin or HbA1 c respectively. CONCLUSION: GES holds great promises to be an effective obesity treatment. However, stronger evidence is required through more studies with a standardized way of carrying out trials and reporting outcomes, to determine the long-term effect of GES on obesity.

  9. Multicycle fatigue tests of 45G17Yu3 steel under conditions of electric stimulation. Evolution of grain ensemble

    International Nuclear Information System (INIS)

    Using methods of metallography a study is made into the behaviour of grain ensembles and intragranular structure of steel 45G17Yu3 on high-cycle fatigue testing under conditions of intermediate electric stimulation. It is revealed that electric stimulation has an essential effect on steel structure formed as on rolling (initial state structure) so on fatigue testing. The steel fracture resulted from high-cycle fatigue tests, performed using both a continuous regime and electric stimulation and is accompanied by multiple microtwinning. The observed enhancement of operational capability of the specimens subjected to intermediate electric stimulation may be connected with deceleration of martensitic γ→ε transformation that actively proceeds under conditions of microtwinning in the austenitic steel

  10. Estimation of Optical Stimulus Amplitude for Balance Training Using Electrical Stimulation of the Vestibular System

    Science.gov (United States)

    Goel, R.; De Dios, Y. E.; Cohen, H. S.; Bloomberg, J. J.; Mulavara, A. P.

    2016-01-01

    Sensorimotor changes such as postural and gait instabilities can affect the functional performance of astronauts following gravitational transitions. By training astronauts preflight with supra-threshold noisy stochastic vestibular stimulation (SVS), the central nervous system can be trained to reweight sensory information by utilizing veridical information from other sensory inputs, such as vision and proprioception, for postural and gait control. This, in turn, can enhance functional performance in novel gravitational environments. The optimal maximum amplitude of stimulation to simulate the effect of deterioration in vestibular inputs for preflight training or for evaluating vestibular contribution in functional tests in general, however, has not yet been identified. Most studies have used arbitrary but fixed maximum current amplitudes from 3 to 5 mA in the medio-lateral (ML) direction to disrupt balance function in both ML and anterior-posterior directions in healthy adults. The goal of this study was to determine the minimum SVS level that yields an equivalently degraded balance performance. Fourteen subjects stood on a compliant surface with their eyes closed and were instructed to maintain a stable upright stance. Measures of stability of the head, trunk, and whole body were quantified in the ML direction. Objective perceptual motion thresholds, were estimated ahead of time by having subjects sit on a chair with their eyes closed and giving 1 Hz bipolar binaural sinusoidal electrical stimulation at various current amplitudes. Results from the balance task suggest that using stimulation amplitudes of 280% of motion-perceptual threshold (2.2 mA on average) significantly degraded balance performance and increasing the stimulation amplitude did not lead to further degradation. We anticipate that preflight training using supra-threshold SVS stimulation will be a component of preflight sensorimotor adaptability training designed to improve adaptability to novel

  11. Paresia diafragmática bilateral idiopática Idiopathic bilateral diaphragmatic paresis

    Directory of Open Access Journals (Sweden)

    Mônica Corso Pereira

    2006-10-01

    Full Text Available Relata-se o caso de um paciente com dispnéia intensa ao se deitar, em que foram excluídas doenças pulmonares, neuromusculares ou cardíacas, cuja investigação revelou paresia diafragmática bilateral. Um sinal chave para o diagnóstico foi a evidência de respiração paradoxal com o doente em decúbito supino. Havia piora da oxigenação e da capacidade vital forçada com a mudança da posição ortostática para supina. A fluoroscopia ortostática foi normal. A pressão inspiratória máxima estava muito reduzida. A estimulação elétrica transcutânea do diafragma foi normal, e a eletroestimulação do nervo frênico mostrou ausência de resposta, permitindo o diagnóstico de paresia bilateral do diafragma.We report the case of a patient with severe dyspnea upon reclining. Lung disease, neuromuscular disorders and heart disease were ruled out. However, during the course of the investigation, bilateral diaphragmatic paresis was discovered. A key sign leading to the diagnosis was evidence of paradoxical respiration in the dorsal decubitus position. When the patient was moved from the orthostatic position to the dorsal decubitus position, oxygenation and forced vital capacity worsened. The orthostatic fluoroscopy was normal. Maximal inspiratory pressure was severely reduced. The responses to transcutaneous electric stimulation of the diaphragm were normal. However, electric stimulation of the phrenic nerve produced no response, leading to the diagnosis of bilateral diaphragmatic paresis.

  12. Electrical stimulation of quadriceps femoris in an elite weight lifter: a single subject experiment.

    Science.gov (United States)

    Delitto, A; Brown, M; Strube, M J; Rose, S J; Lehman, R C

    1989-06-01

    The response to treatment of high intensity neuromuscular electrical stimulation (NMES) to both quadriceps femoris muscles as an adjunct to ongoing weight training was evaluated using a single subject experimental design. For an elite weight lifter weekly maximal measurements of snatch (S), clean and jerk (CJ), and front squat (SQ) were obtained over 4 months during which the subject weight trained daily for 3 h. The 1st month, baseline data were collected. After baseline measurements, a 1-month period of high-intensity NMES was added to the subject's weight training. NMES was then withdrawn for 1 month and administered once more for 2 weeks. Three quadriceps femoris muscle biopsies were taken, two during the initial baseline period and one just before the end of the first stimulation period. The results showed a significant and clear relationship between performance gains and NMES administration and withdrawal. Steep gains for S, CJ, and SQ were seen after 2 weeks of stimulation, with front squat showing a 20-kg increase within the 1st week of both stimulation periods. Muscle biopsy showed an increased type I fiber area, decreased type IIa and IIb fiber area, and an increase of type II fibers after NMES. The results of this study support the use of high-dose NMES as an adjunct to weight training in elite lifters. PMID:2674035

  13. Comparison of efficiency of Kinesio® taping and electrical stimulation in patients with patellofemoral pain syndrome

    OpenAIRE

    Kuru, Tugba; Yaliman, Ayse; Dereli, E. Elcin

    2012-01-01

    Objective: The aim of this study was to compare the efficiency of Kinesio® taping and electrical stimulation in the treatment of patellofemoral pain syndrome. Methods: Thirty patients (26 females, 4 females; mean age: 32.9±12.2 years) with patellofemoral pain syndrome were equally divided into two groups; the KT group receiving Kinesio® taping and an exercise program, and the ES group receiving electrical stimulation and the same exercise program. All patients received stretching and stren...

  14. BIOMECHANICAL ANALYSYS OF LOWER EXTREMITIES DURING CONVENTIONAL AND FUNCTIONAL ELECTRICAL STIMULATION (FES) ROWING IN NON-DISABLED INDIVIDUALS

    OpenAIRE

    Takeshima, Masaaki; Shimada, Yoichi; Matsunaga, Toshiki; Iwami, Takehiro; HIRAMOTO, Kazuhiko

    2010-01-01

    Functional electrical stimulation (FES) rowing is a whole-body exercise in which the lower extremities are moved by electric stimulation and the upper extremities are moved voluntarily by paraplegics. The purpose of this study was to identify the kinematic factors of the lower extremities required to perform FES-rowing through the biomechanical analysis. Eighteen healthy adult men participated in this study. A mathematical model was developed to analyze the conventional rowing with or without...

  15. Neuromuscular electrical stimulation improves exercise tolerance in chronic obstructive pulmonary disease patients with better preserved fat-free mass

    OpenAIRE

    Lara Maris Nápolis; Simone Dal Corso; José Alberto Neder; Carla Malaguti; Ana Cristina Oliveira Gimenes; Luiz Eduardo Nery

    2011-01-01

    BACKGROUND: High-frequency neuromuscular electrical stimulation increases exercise tolerance in patients with advanced chronic obstructive pulmonary disease (COPD patients). However, it is conceivable that its benefits are more prominent in patients with better-preserved peripheral muscle function and structure. OBJECTIVE: To investigate the effects of high-frequency neuromuscular electrical stimulation in COPD patients with better-preserved peripheral muscle function. Design: Prospective and...

  16. Synchronization of Ghostburster neuron in external electrical stimulation via H{sub {infinity}} variable universe fuzzy adaptive control

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jiang [School of Electrical and Automation Engineering, Tianjin University, Tianjin 300072 (China)], E-mail: jiangwang@tju.edu.cn; Chen Lisong; Deng Bin [School of Electrical and Automation Engineering, Tianjin University, Tianjin 300072 (China)

    2009-03-15

    In this paper, H{sub {infinity}} variable universe fuzzy adaptive control law is derived and applied to synchronize two unidirectional coupled Ghostbursters neurons under external electrical stimulation. Firstly, the dynamical behavior of the nonlinear Ghostburster model responding to various external electrical stimulations is studied. Then, using the results of the analysis, a robust adaptive variable universe fuzzy control scheme is designed to synchronize two unidirectional coupled neurons. Numerical simulations demonstrate the validity and feasibility of the proposed method.

  17. Improving Balance Function Using Low Levels of Electrical Stimulation of the Balance Organs

    Science.gov (United States)

    Bloomberg, Jacob; Reschke, Millard; Mulavara, Ajitkumar; Wood, Scott; Serrador, Jorge; Fiedler, Matthew; Kofman, Igor; Peters, Brian T.; Cohen, Helen

    2012-01-01

    Crewmembers returning from long-duration space flight face significant challenges due to the microgravity-induced inappropriate adaptations in balance/ sensorimotor function. The Neuroscience Laboratory at JSC is developing a method based on stochastic resonance to enhance the brain s ability to detect signals from the balance organs of the inner ear and use them for rapid improvement in balance skill, especially when combined with balance training exercises. This method involves a stimulus delivery system that is wearable/portable providing imperceptible electrical stimulation to the balance organs of the human body. Stochastic resonance (SR) is a phenomenon whereby the response of a nonlinear system to a weak periodic input signal is optimized by the presence of a particular non-zero level of noise. This phenomenon of SR is based on the concept of maximizing the flow of information through a system by a non-zero level of noise. Application of imperceptible SR noise coupled with sensory input in humans has been shown to improve motor, cardiovascular, visual, hearing, and balance functions. SR increases contrast sensitivity and luminance detection; lowers the absolute threshold for tone detection in normal hearing individuals; improves homeostatic function in the human blood pressure regulatory system; improves noise-enhanced muscle spindle function; and improves detection of weak tactile stimuli using mechanical or electrical stimulation. SR noise has been shown to improve postural control when applied as mechanical noise to the soles of the feet, or when applied as electrical noise at the knee and to the back muscles.

  18. Effect of low-frequency pulse percutaneous electric stimulation on peripheral nerve injuries at different sites

    Institute of Scientific and Technical Information of China (English)

    Jinwu Wang; Liye Chen; Qi Li; Weifeng Ni; Min Zhang; Shangchun Guo; Bingfang Zeng

    2006-01-01

    BACKGROUND: The postoperative recovery of nerve function in patients with peripheral nerve injury is always an important problem to solve after treatment. The electric stimulation induced electromagnetic field can nourish nerve, postpone muscular atrophy, and help the postoperative neuromuscular function.OBJECTIVE: To observe the effects of low-frequency pulse percutaneous electric stimulation on the functional recovery of postoperative patients with peripheral nerve injury, and quantitatively evaluate the results of electromyogram (EMG) examination before and after treatment.DESIGN: A retrospective case analysis.SETTING: The Sixth People's Hospital affiliated to Shanghai Jiaotong University.PARTICIPANTS: Nineteen postoperative inpatients with peripheral nerve injury were selected from the Department of Orthopaedics, the Sixth People's Hospital affiliated to Shanghai Jiaotong University from June 2005 to January 2006, including 13 males and 6 females aged 24-62 years with an average of 36 years old.There were 3 cases of brachial plexus nerve injury, 3 of median nerve injury, 7 of radial nerve injury, 3 of ulnar nerve injury and 3 of common peroneal nerve injury, and all the patients received probing nerve fiber restoration. Their main preoperative manifestations were dennervation, pain in limbs, motor and sensory disturbances. All the 19 patients were informed with the therapeutic program and items for evaluation.METHODS : ① Low-frequency pulse percutaneous electric stimulation apparatus: The patients were given electric stimulation with the TERESA cantata instrument (TERESA-0, Shanghai Teresa Health Technology, Co.,Ltd.). The patients were stimulated with symmetric square waves of 1-111 Hz, and the intensity was 1.2-5.0 mA, and it was gradually adjusted according to the recovered conditions of neural regeneration following the principle that the intensity was strong enough and the patients felt no obvious upset. They were treated for 4-24 weeks, 10-30 minutes

  19. Muscular reflexes elicited by electrical stimulation of the anterior cruciate ligament in humans

    DEFF Research Database (Denmark)

    Dyhre-Poulsen, P; Krogsgaard, M R

    2000-01-01

    no sign of ACL disease, thin wire electrodes were inserted into the proximal and mid parts of the ACL. Postoperatively, the sensory nerve fibers inside the ACL were stimulated electrically while motor activity in the knee muscles was recorded using electromyography. In seven of the eight patients, a...... muscular contraction of the semitendinosus muscle could be elicited with stimulus trains consisting of at least two stimuli. The latency was 95 +/- 35 ms. Stimulation during isometric contraction of either extensor or flexor muscles elicited a short, complete inhibition of the muscle activity in the...... contracting muscles. The latency of the inhibitory responses was 65 +/- 20 ms in the semitendinosus muscle and 70 +/- 15 ms in the rectus femoris muscle....

  20. Mechanical design and driving mechanism of an isokinetic functional electrical stimulation-based leg stepping trainer.

    Science.gov (United States)

    Hamzaid, N A; Fornusek, C; Ruys, A; Davis, G M

    2007-12-01

    The mechanical design of a constant velocity (isokinetic) leg stepping trainer driven by functional electrical stimulation-evoked muscle contractions was the focus of this paper. The system was conceived for training the leg muscles of neurologically-impaired patients. A commercially available slider crank mechanism for elliptical stepping exercise was adapted to a motorized isokinetic driving mechanism. The exercise system permits constant-velocity pedalling at cadences of 1-60 rev x min(-1). The variable-velocity feature allows low pedalling forces for individuals with very weak leg muscles, yet provides resistance to higher pedalling effort in stronger patients. In the future, the system will be integrated with a computer-controlled neuromuscular stimulator and a feedback control unit to monitor training responses of spinal cord-injured, stroke and head injury patients. PMID:18274073

  1. Functional Electrical Stimulation Alters the Postural Component of Locomotor Activity in Healthy Humans

    Science.gov (United States)

    Talis, Vera; Ballay, Yves; Grishin, Alexander; Pozzo, Thierry

    2015-01-01

    Knowledge of the effects of Functional Electrical Stimulation (FES) of different intensity on postural stability during walking in healthy subjects is necessary before these relationships in patients with postural disorders can be assessed and understood. We examined healthy subjects in Control group walking on a treadmill for 40 min and in FES group—provided with 30 min of stimulation, which intensity increased every 10 min. The main difference between Control and FES group was the progressive increase of trunk oscillations in sagittal, frontal, and horizontal planes and an increase of relative stance duration in parallel with FES intensity increase. Both Control and FES groups exhibited shank elevation angle increase as an after-effect. It is concluded, that high intensity FES significantly changes the postural component of locomotor activity, but the fatigue signs afterwards were not FES specific. PMID:26733791

  2. The combined effects of transcutaneous electrical nerve stimulation (TENS) and stretching on muscle hardness and pressure pain threshold

    Science.gov (United States)

    Karasuno, Hiroshi; Ogihara, Hisayoshi; Morishita, Katsuyuki; Yokoi, Yuka; Fujiwara, Takayuki; Ogoma, Yoshiro; Abe, Koji

    2016-01-01

    [Purpose] This study aimed to clarify the immediate effects of a combined transcutaneous electrical nerve stimulation and stretching protocol. [Subjects] Fifteen healthy young males volunteered to participate in this study. The inclusion criterion was a straight leg raising range of motion of less than 70 degrees. [Methods] Subjects performed two protocols: 1) stretching (S group) of the medial hamstrings, and 2) tanscutaneous electrical nerve stimulation (100 Hz) with stretching (TS group). The TS group included a 20-minute electrical stimulation period followed by 10 minutes of stretching. The S group performed 10 minutes of stretching. Muscle hardness, pressure pain threshold, and straight leg raising range of motion were analyzed to evaluate the effects. The data were collected before transcutaneous electrical nerve stimulation (T1), before stretching (T2), immediately after stretching (T3), and 10 minutes after stretching (T4). [Results] Combined transcutaneous electrical nerve stimulation and stretching had significantly beneficial effects on muscle hardness, pressure pain threshold, and straight leg raising range of motion at T2, T3, and T4 compared with T1. [Conclusion] These results support the belief that transcutaneous electrical nerve stimulation combined with stretching is effective in reducing pain and decreasing muscle hardness, thus increasing range of motion. PMID:27190439

  3. Pilot acute study of feedback-controlled retrograde peristalsis invoked by neural gastric electrical stimulation

    International Nuclear Information System (INIS)

    Neural gastric electrical stimulation (NGES) is a new method for invoking gastric contractions under microprocessor control. However, optimization of this technique using feedback mechanisms to minimize power consumption and maximize effectiveness has been lacking. The present pilot study proposes a prototype feedback-controlled neural gastric electric stimulator for the treatment of obesity. Both force-based and inter-electrode impedance-based feedback neurostimulators were implemented and tested. Four mongrel dogs (2 M, 2 F, weight 14.9 ± 2.3 kg) underwent subserosal implantation of two-channel, 1 cm, bipolar electrode leads and two force transducers in the distal antrum. Two of the dogs were stimulated with a force feedback system utilizing the force transducers, and the other two animals were stimulated utilizing an inter-electrode impedance-based feedback system utilizing the proximal electrode leads. Both feedback systems were able to recognize erythromycin-driven contractions of the stomach and were capable of overriding them with NGES-invoked retrograde contractions which exceeded the magnitudes of the erythromycin-driven contractions by an average of 100.6 ± 33.5% in all animals. The NGES-invoked contractions blocked the erythromycin-driven contractions past the proximal electrode pair and induced temporary gastroparesis in the vicinity of the distal force transducer despite the continuing erythromycin infusion. The amplitudes of the erythromycin-invoked contractions in the vicinity of the proximal force transducer decreased abruptly by an average of 47.9 ± 6.3% in all four dogs after triggering-invoked retrograde contractions, regardless of the specific feedback-controlled mechanism. The proposed technique could be helpful for retaining food longer in the stomach, thus inducing early satiety and diminishing food intake

  4. Salivary alpha-amylase and cortisol responsiveness following electrically stimulated physical stress in bipolar disorder patients

    Directory of Open Access Journals (Sweden)

    Tanaka Y

    2013-12-01

    Full Text Available Yoshihiro Tanaka, Yoshihiro Maruyama, Yoshinobu Ishitobi, Aimi Kawano, Tomoko Ando, Rie Ikeda, Ayako Inoue, Junko Imanaga, Shizuko Okamoto, Masayuki Kanehisa, Taiga Ninomiya, Jusen Tsuru, Jotaro Akiyoshi Department of Neuropsychiatry, Faculty of Medicine, Oita University, Hasama-Machi, Oita, Japan Background: Bipolar disorder (BP is often associated with a change in hypothalamus–pituitary–adrenal axis function change due to chronic stress. Salivary α-amylase (sAA levels increase in response to psychosocial stress and thus function as a marker of sympathoadrenal medullary system activity. However, sAA has been studied less often than salivary cortisol in BP patients. Method: We measured Profile of Mood States and State-Trait Anxiety Inventory scores, heart rate variability, and salivary cortisol levels during electrical stimulation stress in 25 BP patients and 22 healthy volunteers. Results: Tension–anxiety, depression–dejection, anger–hostility, fatigue, and confusion scores in BP patients significantly increased compared with those of the healthy controls. In contrast, the vigor scores of BP patients significantly decreased compared with those of the healthy controls. Significant difference in the sAA levels was observed between BP patients and healthy controls. sAA of female patients was significantly higher than that of female healthy controls, and sAA in male patients tended to be higher than that of male healthy controls. No difference in salivary cortisol was observed between BP patients and the healthy controls. Only three time points were measured before and after the electrical stimulation stress. Furthermore, sAA secretion by BP patients increased before and after electrical stimulation. Conclusion: These preliminary results suggest that sAA may be a useful biological marker for BP patients. Keywords: HPA axis, bipolar disorder, α-amylase, cortisol, SAM activity

  5. Artifacts produced during electrical stimulation of the vestibular nerve in cats. [autonomic nervous system components of motion sickness

    Science.gov (United States)

    Tang, P. C.

    1973-01-01

    Evidence is presented to indicate that evoked potentials in the recurrent laryngeal, the cervical sympathetic, and the phrenic nerve, commonly reported as being elicited by vestibular nerve stimulation, may be due to stimulation of structures other than the vestibular nerve. Experiments carried out in decerebrated cats indicated that stimulation of the petrous bone and not that of the vestibular nerve is responsible for the genesis of evoked potentials in the recurrent laryngeal and the cervical sympathetic nerves. The phrenic response to electrical stimulation applied through bipolar straight electrodes appears to be the result of stimulation of the facial nerve in the facial canal by current spread along the petrous bone, since stimulation of the suspended facial nerve evoked potentials only in the phrenic nerve and not in the recurrent laryngeal nerve. These findings indicate that autonomic components of motion sickness represent the secondary reactions and not the primary responses to vestibular stimulation.

  6. Induction of long-term depression-like plasticity by pairings of motor imagination and peripheral electrical stimulation

    Directory of Open Access Journals (Sweden)

    Imran Khan Niazi

    2015-12-01

    Full Text Available Long-term depression (LTD and long-term potentiation (LTP-like plasticity are models of synaptic plasticity which have been associated with memory and learning. The induction of LTD and LTP-like plasticity, using different stimulation protocols, has been proposed as a means of addressing abnormalities in cortical excitability associated with conditions such as focal hand dystonia and stroke. The aim of this study was to investigate whether the excitability of the cortical projections to the tibialis anterior muscle could be decreased when dorsiflexion of the ankle joint was imagined and paired with peripheral electrical stimulation of the nerve supplying the antagonist soleus muscle. The effect of stimulus timing was evaluated by comparing paired stimulation timed to reach the cortex before, at and after the onset of imagined movement. Fourteen healthy subjects participated in six experimental sessions held on non-consecutive days. The timing of stimulation delivery was determined offline based on the contingent negative variation (CNV of electroencephalography (EEG brain data obtained during imagined dorsiflexion. Afferent stimulation was provided via a single pulse electrical stimulation to the peripheral nerve paired, based on the CNV, with motor imagination of ankle dorsiflexion. A significant decrease (P=0.001 in the excitability of the cortical projection of tibialis anterior was observed when the afferent volley from the electrical stimulation of the tibial nerve (TN reached the cortex at the onset of motor imagination based on the CNV. When TN stimulation was delivered before (P=0.62, or after (P=0.23 imagined movement onset there was no significant effect. Nor was a significant effect found when electrical stimulation of the TN was applied independent of imagined movement (P=0.45. Therefore, the excitability of the cortical projection to a muscle can be inhibited when electrical stimulation of the nerve supplying the antagonist muscle

  7. Functional Changes in the Care-needing Elderly after Surface Electrical Stimulation to the Abdomen

    OpenAIRE

    Miura, Misa; Seki, Kazunori; Ito, Osamu; Handa, Yasunobu; Kohzuki, Masahiro

    2012-01-01

    Background: Strength of the trunk muscles is a key component of motor control, but it declines easily with the process of aging and/or disuse. Objectives: To investigate the effects of surface electrical stimulation (ES) to the abdominal muscles and the motor performance for care-needing elderly. Design: Controlled trial. Participants: Twenty-one elderly people (60–90 years) with care-needing, who were admitted to a nursing home or hospital for daily care and their score of Barthel Index had ...

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

    Science.gov (United States)

    Li, C B; Li, J; Zhou, G H; Lametsch, R; Ertbjerg, P; Brüggemann, D A; Huang, H G; Karlsson, A H; Hviid, M; Lundström, K

    2012-05-01

    The objective of this study was to investigate the response of sarcoplasmic proteins in bovine LM to low-voltage electrical stimulation (ES; 80 V, 35 s) after dressing and its contribution to meat tenderization at an early postmortem time. Proteome analysis showed that ES resulted in decreased (P tenderization, resulting in lesser (P tenderization of beef. Our results suggested the possible importance of the activation of μ-calpain, phosphorylation of sarcoplasmic proteins, and release of lysosomal enzymes for ES-induced tenderization of beef muscle. PMID:22147478

  9. Preventing Ischial Pressure Ulcers: III. Clinical Pilot Study of Chronic Neuromuscular Electrical Stimulation

    Directory of Open Access Journals (Sweden)

    Hilton M. Kaplan

    2011-01-01

    Full Text Available Objective: BIONs™ (BIOnic Neurons are injectable, wireless microstimulators that make chronic BION Active Seating (BAS possible for pressure ulcer prevention (PUP. Neuromuscular electrical stimulation (NMES produces skeletal motion and activates trophic factors, counteracting three major etiological mechanisms leading to pressure ulcers (PUs: immobility, soft-tissue atrophy, and ischemia. Companion papers I and II reviewed prior experience with NMES for PUP, and analyzed the biomechanical considerations, respectively. This paper presents a treatment strategy derived from this analysis, and the clinical results of the first three cases.

  10. Detailed 3D models of the induced electric field of transcranial magnetic stimulation coils

    International Nuclear Information System (INIS)

    Previous models neglected contributions from current elements spanning the full geometric extent of wires in transcranial magnetic stimulation (TMS) coils. A detailed account of TMS coil wiring geometry is shown to provide significant improvements in the accuracy of electric field (E-field) models. Modeling E-field dependence based on the TMS coil's wire width, height, shape and number of turns clearly improved the fit of calculated-to-measured E-fields near the coil body. Detailed E-field models were accurate up to the surface of the coil body (within 0.5% of measured) where simple models were often inadequate (up to 32% different from measured)

  11. Robust synchronization control of coupled chaotic neurons under external electrical stimulation

    International Nuclear Information System (INIS)

    In this paper, a robust adaptive neural network (NN) controller is proposed to realize the synchronization of two gap junction coupled chaotic FitzHugh-Nagumo (FHN) neurons under external electrical stimulation. Based on the Lyapunov stability theory, we derive the update laws of NN for approximating the nonlinear uncertain functions of the error dynamical system. The control scheme is robust to the uncertainties such as approximate error, ionic channel noise and external disturbances. Chaos synchronization is obtained by proper choice of the control parameters. The simulation results demonstrate the effectiveness of the proposed control method.

  12. Experimental model for transcutaneous electrical nerve stimulation on ischemic random skin flap in rats

    OpenAIRE

    Liebano Richard Eloin; Ferreira Lydia Masako; Sabino Neto Miguel

    2003-01-01

    The objective of this paper was to develop an experimental model to be used in the study of Transcutaneous Electrical Nerve Stimulation (TENS) on viability of random skin flap in rats. The sample was 15 Wistar-EPM rats. The random skin flap measured 10x4 cm and a plastic barrier was placed between the flap and the donnor site. The animals were submited to TENS for 1 hour immediately after the surgery and on the two subsequent days. On the seventh postoperative day, the percentage of necrotic ...

  13. [The electrical stimulation bicycle: a neuroprosthesis for the everyday use of paraplegic patients].

    Science.gov (United States)

    Szecsi, J; Fiegel, M; Krafczyk, S; Straube, A; Quintern, J; Brandt, Th

    2004-06-24

    Until recently, few patients with complete paraplegia could walk or stand with the help of functional electrical stimulation (FES) of the leg muscles regularly at home. In comparison, FES cycling with an adapted tricycle is easy to put into practice because the legs remain connected to the pedals and through the use of a tricycle or stationary bicycle, the balancing problems of the patient recedes into the background. In the first German feasibility studies for paraplegic cycling, eleven completely paraplegic patients have been tested so far. The goal is to make FES cycling a daily activity in the lives of as many patients as possible. PMID:15529690

  14. 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 in...... lower (P <0.05) phosphorylation levels of creatine kinase M chain, fructose bisphosphate aldolase C-A, ß-enolase and pyruvate kinase at 3 h postmortem. Zymography indicated an earlier (P <0.05) activation of µ-calpain in ES muscles. Free lysosomal cathepsin B&L activity increased faster (P <0.05) in ES...

  15. Electrical stimulation promotes regeneration of defective peripheral nerves after delayed repair intervals lasting under one month.

    Directory of Open Access Journals (Sweden)

    Chungui Xu

    Full Text Available BACKGROUND: Electrical stimulation (ES has been proven to be an effective means of enhancing the speed and accuracy of nerve regeneration. However, these results were recorded when the procedure was performed almost immediately after nerve injury. In clinical settings, most patients cannot be treated immediately. Some patients with serious trauma or contaminated wounds need to wait for nerve repair surgery. Delays in nerve repair have been shown to be associated with poorer results than immediate surgery. It is not clear whether electrical stimulation still has any effect on nerve regeneration after enough time has elapsed. METHODS: A delayed nerve repair model in which the rats received delayed nerve repair after 1 day, 1 week, 1 month, and 2 months was designed. At each point in time, the nerve stumps of half the rats were bridged with an absorbable conduit and the rats were given 1 h of weak electrical stimulation. The other half was not treated. In order to analyze the morphological and molecular differences among these groups, 6 ES rats and 6 sham ES rats per point in time were killed 5 days after surgery. The other rats in each group were allowed to recover for 6 weeks before the final functional test and tissue observation. RESULTS: The amounts of myelinated fibers in the distal nerve stumps decreased as the delay in repair increased for both ES rats and sham ES rats. In the 1-day-delay and 1-week-delay groups, there were more fibers in ES rats than in sham ES rats. And the compound muscle action potential (CMAP and motor nerve conduction velocity (MNCV results were better for ES rats in these two groups. In order to analyze the mechanisms underlying these differences, Masson staining was performed on the distal nerves and quantitative PCR on the spinal cords. Results showed that, after delays in repair of 1 month and 2 months, there was more collagen tissue hyperplasia in the distal nerve in all rats. The brain-derived neurotrophic

  16. Robust synchronization control of coupled chaotic neurons under external electrical stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Che Yanqiu [School of Electrical Engineering and Automation, Tianjin University, Tianjin 300072 (China); Wang Jiang [School of Electrical Engineering and Automation, Tianjin University, Tianjin 300072 (China)], E-mail: jiangwang@tju.edu.cn; Zhou Sisi; Deng Bin [School of Electrical Engineering and Automation, Tianjin University, Tianjin 300072 (China)

    2009-05-15

    In this paper, a robust adaptive neural network (NN) controller is proposed to realize the synchronization of two gap junction coupled chaotic FitzHugh-Nagumo (FHN) neurons under external electrical stimulation. Based on the Lyapunov stability theory, we derive the update laws of NN for approximating the nonlinear uncertain functions of the error dynamical system. The control scheme is robust to the uncertainties such as approximate error, ionic channel noise and external disturbances. Chaos synchronization is obtained by proper choice of the control parameters. The simulation results demonstrate the effectiveness of the proposed control method.

  17. Electrical Stimulation: A Panacea for Disease?: DARPA Investigates New Bioelectrical Interfaces for a Range of Disorders.

    Science.gov (United States)

    Grifantini, Kristina

    2016-01-01

    It seems simple: send a small electrical current to a major nerve in the body and stimulate hormones and organs to react in the way you want. New efforts by research teams are doing just that, zapping peripheral nerves attached to major organs in the hopes of addressing problems as diverse as inflammatory bowel disease, chronic pain, and posttraumatic stress disorder. Thanks to the continued advance of smaller and more efficient electronics, researchers are finding new ways to develop implantable bioelectrical devices to treat a wide range of ailments. PMID:27414632

  18. Evaluation of the neuromuscular compartments in the peroneus longus muscle through electrical stimulation and accelerometry

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    Guillermo A. Mendez

    2013-10-01

    Full Text Available BACKGROUND: Muscles are innervated exclusively by a nerve branch and possess definite actions. However, mammalian skeletal muscles, such as the trapezius, the medial gastrocnemius, and the peroneus longus, are compartmentalized. In the peroneus longus muscle, multiple motor points, which innervate individual neuromuscular compartments (NMC, the superior (S-NMC, anteroinferior (AI-NMC, and posteroinferior (PI-NMC, have been described. The contribution of each neuromuscular compartment to the final action of the muscle is fundamental for the rehabilitation of patients afflicted by neurological and muscle dysfunctions. Interventions are often based on electrical principles that take advantage of the physiological characteristics of muscles and nerves to generate therapeutic effects. OBJECTIVE: To compare the effects of stimulating the different neuromuscular compartments (NMCs of the peroneus longus muscle on the motor threshold (MT and acceleration of the foot. METHOD: This is a cross-sectional study comprising 37 subjects. The three NMCs of the peroneus longus muscle were stimulated, and the acceleration of the foot and the motor threshold of each NMC were evaluated. A repeated measures analysis of variance with Bonferroni corrections of two intra-subjects factors was performed. RESULTS: The stimulation of the different NMCs did not result in any differences in MT (F=2.635, P=0.079. There were significant differences between the axes of acceleration caused by the stimulation of the different NMCs (F=56,233; P=0.000. The stimulation of the posteroinferior compartment resulted in the greatest acceleration in the X-axis (mean 0.614; standard deviation 0.253. CONCLUSIONS: The posteroinferior compartment primarily contributes to the eversion movement of the foot. NMCs have specific functional roles that contribute to the actions of the muscles to which they belong.

  19. The Parameters of Transcutaneous Electrical Nerve Stimulation Are Critical to Its Regenerative Effects When Applied Just after a Sciatic Crush Lesion in Mice

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    Diana Cavalcante Miranda de Assis

    2014-01-01

    Full Text Available We investigated the effect of two frequencies of transcutaneous electrical nerve stimulation (TENS applied immediately after lesion on peripheral nerve regeneration after a mouse sciatic crush injury. The animals were anesthetized and subjected to crushing of the right sciatic nerve and then separated into three groups: nontreated, Low-TENS (4 Hz, and High-TENS (100 Hz. The animals of Low- and High-TENS groups were stimulated for 2 h immediately after the surgical procedure, while the nontreated group was only positioned for the same period. After five weeks the animals were euthanized, and the nerves dissected bilaterally for histological and histomorphometric analysis. Histological assessment by light and electron microscopy showed that High-TENS and nontreated nerves had a similar profile, with extensive signs of degeneration. Conversely, Low-TENS led to increased regeneration, displaying histological aspects similar to control nerves. High-TENS also led to decreased density of fibers in the range of 6–12 μm diameter and decreased fiber diameter and myelin area in the range of 0–2 μm diameter. These findings suggest that High-TENS applied just after a peripheral nerve crush may be deleterious for regeneration, whereas Low-TENS may increase nerve regeneration capacity.

  20. The sound sensation of apical electric stimulation in cochlear implant recipients with contralateral residual hearing.

    Directory of Open Access Journals (Sweden)

    Diane S Lazard

    Full Text Available BACKGROUND: Studies using vocoders as acoustic simulators of cochlear implants have generally focused on simulation of speech understanding, gender recognition, or music appreciation. The aim of the present experiment was to study the auditory sensation perceived by cochlear implant (CI recipients with steady electrical stimulation on the most-apical electrode. METHODOLOGY/PRINCIPAL FINDINGS: Five unilateral CI users with contralateral residual hearing were asked to vary the parameters of an acoustic signal played to the non-implanted ear, in order to match its sensation to that of the electric stimulus. They also provided a rating of similarity between each acoustic sound they selected and the electric stimulus. On average across subjects, the sound rated as most similar was a complex signal with a concentration of energy around 523 Hz. This sound was inharmonic in 3 out of 5 subjects with a moderate, progressive increase in the spacing between the frequency components. CONCLUSIONS/SIGNIFICANCE: For these subjects, the sound sensation created by steady electric stimulation on the most-apical electrode was neither a white noise nor a pure tone, but a complex signal with a progressive increase in the spacing between the frequency components in 3 out of 5 subjects. Knowing whether the inharmonic nature of the sound was related to the fact that the non-implanted ear was impaired has to be explored in single-sided deafened patients with a contralateral CI. These results may be used in the future to better understand peripheral and central auditory processing in relation to cochlear implants.

  1. Resuscitation therapy for traumatic brain injury-induced coma in rats:mechanisms of median nerve electrical stimulation

    Institute of Scientific and Technical Information of China (English)

    Zhen Feng; Ying-jun Zhong; Liang Wang; Tian-qi Wei

    2015-01-01

    In this study, rats were put into traumatic brain injury-induced coma and treated with median nerve electrical stimulation. We explored the wake-promoting effect, and possible mechanisms, of median nerve electrical stimulation. Electrical stimulation upregulated the expression levels of orexin-A and its receptor OX1R in the rat prefrontal cortex. Orexin-A expression gradually in-creased with increasing stimulation, while OX1R expression reached a peak at 12 hours and then decreased. In addition, after the OX1R antagonist, SB334867, was injected into the brain of rats after traumatic brain injury, fewer rats were restored to consciousness, and orexin-A and OXIR expression in the prefrontal cortex was downregulated. Our ifndings indicate that median nerve electrical stimulation induced an up-regulation of orexin-A and OX1R expression in the pre-frontal cortex of traumatic brain injury-induced coma rats, which may be a potential mechanism involved in the wake-promoting effects of median nerve electrical stimulation.

  2. Resuscitation therapy for traumatic brain injury-induced coma in rats: mechanisms of median nerve electrical stimulation

    Directory of Open Access Journals (Sweden)

    Zhen Feng

    2015-01-01

    Full Text Available In this study, rats were put into traumatic brain injury-induced coma and treated with median nerve electrical stimulation. We explored the wake-promoting effect, and possible mechanisms, of median nerve electrical stimulation. Electrical stimulation upregulated the expression levels of orexin-A and its receptor OX1R in the rat prefrontal cortex. Orexin-A expression gradually increased with increasing stimulation, while OX1R expression reached a peak at 12 hours and then decreased. In addition, after the OX1R antagonist, SB334867, was injected into the brain of rats after traumatic brain injury, fewer rats were restored to consciousness, and orexin-A and OXIR expression in the prefrontal cortex was downregulated. Our findings indicate that median nerve electrical stimulation induced an up-regulation of orexin-A and OX1R expression in the prefrontal cortex of traumatic brain injury-induced coma rats, which may be a potential mechanism involved in the wake-promoting effects of median nerve electrical stimulation.

  3. Establishment of an animal model of extra-vertebral foramen cervical nerve entrapment by local electrical stimulation and selection of suitable stimulation parameters

    Institute of Scientific and Technical Information of China (English)

    Jinwu Wang; Zhenan Zhu; Kerong Dai; Guang H Yue; Juliet Hou; Qi Li; Jian Tang; Biyu Rui; Shangchun Guo; Haitao Jiang; Cunyi Fan; You Wang

    2011-01-01

    A rat model of extra-vertebral foramen cervical nerve entrapment was established according to the following parameters: stimulation intensity 20 V; frequency 50 Hz; pulse width 200 μs; duration 333 ms/s for a total of 8 hours. After the electrical stimulation, rats exhibited mild muscle fiber atrophy, mild inflammatory exudates, connective tissue local fibrosis and chondrocyte metaplasia. Mean muscle fiber cross-sectional area was reduced. The nerve myelin sheath continuity was partially demyelinated. The microstructure of nerve cells was disrupted and these symptoms worsened with prolongation of the stimulation. The shoulder, neck and upper extremity muscles on the tested side demonstrated positive sharp waves and fibrillations. The severity increased with continuation of the stimulation. High amplitude and polyphasic motor unit potentials gradually appeared. Similar findings were seen in the contralateral side, but at a less severe level.

  4. Low-frequency electrical stimulation improves neurite outgrowth of dorsal root ganglion neurons in vitro via upregulating Ca2+-mediated brain-derived neurotrophic factor expression

    Institute of Scientific and Technical Information of China (English)

    Lidan Wan; Rong Xia; Wenlong Ding

    2010-01-01

    Short-term,low-frequency electrical stimulation of neural tissues significantly enhances axonal regeneration of peripheral nerves following injury.However,little is known about the mechanisms of electrical stimulation to induce neurite outgrowth.In the present study,short-term,low-frequency electrical stimulation,using identical stimulation parameters of in vivo experiments,was administered to in vitro dorsal root ganglion(DRG)neurons.Enhanced neurite outgrowth,as well as synthesis and release of brain-derived neurotrophic factor(BDNF),were examined in electrical stimulation-treated DRG neuronal cultures.Because the effects of electrical stimulation on neuronal intracellular signaling molecules are less reported,classic calcium intracellular signals are directly or indirectly involved in electrical stimulation effects on neurons.Cultured DRG neurons were pretreated with the calcium channel blocker nifedipine,followed by electrical stimulation.Results suggested that electrical stimulation not only promoted in vitro neurite outgrowth,but also enhanced BDNF expression.However,nifedipine reduced electrical stimulation-enhanced neurite outgrowth and BDNF biosynthesis.These results suggest that the promoting effects of electrical stimulation on DRG neurite outgrowth could be associated with altered calcium influx,which is involved induction of neuronal BDNF expression and secretion.

  5. Programmed acute electrical stimulation of ventral tegmental area alleviates depressive-like behavior.

    Science.gov (United States)

    Friedman, Alexander; Frankel, Michael; Flaumenhaft, Yakov; Merenlender, Avia; Pinhasov, Albert; Feder, Yuval; Taler, Michal; Gil-Ad, Irit; Abeles, Moshe; Yadid, Gal

    2009-03-01

    Depressive disorders affect approximately 5% of the population in any given year. Antidepressants may require several weeks to produce their clinical effects. Despite progress being made in this area there is still room and a need to explore additional therapeutic modes to increase treatment effectiveness and responsiveness. Herein, we examined a new method for intervention in depressive states based on deep brain stimulation of the ventral tegmental area (VTA) as a source of incentive motivation and hedonia, in comparison to chemical antidepressants. The pattern of stimulation was fashioned to mimic the firing pattern of VTA neurons in the normal rat. Behavioral manifestations of depression were then monitored weekly using a battery of behavioral tests. The results suggest that treatment with programmed acute electrical stimulation of the VTA substantially alleviates depressive behavior, as compared to chemical antidepressants or electroconvulsive therapy, both in onset time and longitudinal effect. These results were also highly correlated with increases in brain-derived neurotrophic factor mRNA levels in the prefrontal cortex. PMID:18843267

  6. Right Cortical and Axonal Structures Eliciting Ocular Deviation During Electrical Stimulation Mapping in Awake Patients.

    Science.gov (United States)

    Montemurro, Nicola; Herbet, Guillaume; Duffau, Hugues

    2016-07-01

    To investigate the neural network underpinning eye movements, a cortical and subcortical intraoperative mapping using direct electrical stimulation (DES) was achieved in six awake patients during surgery for a right frontal low-grade glioma. We assessed the relationship between the occurrence of ocular deviation during both cortical and axonal DES and the anatomic location for each response. The corresponding stimulation sites were reported on a standard brain template for visual analysis and between-subjects comparisons. Our results showed that DES of the cortical frontal eye field (FEF) elicited horizontal (anterior FEF) or upward (posterior FEF) eye movements in 3 patients, supporting the fact that FEF comprises several distinct functional subregions. In addition, subcortical stimulation of the white matter tracts underneath the FEF evoked conjugate contraversive ocular deviation in 3 other patients. Interestingly, this region seems to be a crossroad between the fronto-striatal tract, the frontal aslant tract, the inferior fronto-occipital fascicle and the superior longitudinal fascicle. No deficits in eye movements were observed following surgery. To our knowledge, this is the first study reporting ocular deviation during axonal electrostimulation mapping of the white matter fibers in awake patients. Therefore, our original data issued from DES give new insights into the cortical and subcortical structures involved in the control of eye movements and their strong relationships with other functional pathways. PMID:27067598

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

    Directory of Open Access Journals (Sweden)

    van Rijn Clementina M

    2011-04-01

    Full Text Available Abstract 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 to investigate HFS-induced central plasticity of sensory processing at the level of the brain using the electroencephalogram (EEG. To this end we measured evoked potentials in response to noxious electrical pinprick-like stimuli applied in the heterotopic skin area before, directly after and 30 minutes after HFS. Results We observed potential cortical electrophysiological correlates of heterotopic facilitation. Two different cortical correlates were found; the first one was a lateralized effect, i.e. a larger N100 amplitude on the conditioned arm than the control arm 30 minutes after end of HFS. This was comparable with the observed lateralized effect of visual analogue scale (VAS scores as response to the mechanical punctate stimuli. The second correlate seems to be a more general (non-lateralized effect, because the result affects both arms. On average for both arms the P200 amplitude increased significantly 30 minutes after end of HFS with respect to baseline. Conclusions We suggest that for studying heterotopic nociceptive facilitation the evoked brain response is suitable and relevant for investigating plasticity at the level of the brain and is perhaps a more sensitive and reliable marker than the perceived pain intensity (e.g. VAS.

  8. Fuzzy control with amplitude/pulse-width modulation of nerve electrical stimulation for muscle force control

    Science.gov (United States)

    Lin, C.-C. K.; Liu, W.-C.; Chan, C.-C.; Ju, M.-S.

    2012-04-01

    The main goal of this study was to study the performance of fuzzy logic controllers combined with simplified hybrid amplitude/pulse-width (AM/PW) modulation to regulate muscle force via nerve electrical stimulation. The recruitment curves with AM/PW and AM modulations were constructed for the calf muscles of rabbits. Integrated with the modulation methods, a proportional-integral-derivative (PID) and three fuzzy logic controllers were designed and applied for the electrical stimulation of tibial nerves to control the ankle torque under isometric conditions. The performance of the two modulation methods combined with the four controllers was compared when the ankle was fixed at three positions for both in vivo experiments and model simulations using a nonlinear muscle model. For the animal experiments, AM/PW modulation performed better than AM modulation alone. The fuzzy PI controller performed marginally better and was resistant to external noises, though it tended to have a larger overshoot. The performance of the controllers had a similar trend in the three different joint positions, and the simulation results with the nonlinear model matched the experimental results well. In conclusion, AM/PW modulation improved controller performance, while the contribution of fuzzy logic was only marginal.

  9. Gastric electrical stimulation for the treatment of obesity: from entrainment to bezoars-a functional review.

    Science.gov (United States)

    Mintchev, Martin P

    2013-01-01

    GROWING WORLDWIDE OBESITY EPIDEMIC HAS PROMPTED THE DEVELOPMENT OF TWO MAIN TREATMENT STREAMS: (a) conservative approaches and (b) invasive techniques. However, only invasive surgical methods have delivered significant and sustainable benefits. Therefore, contemporary research exploration has focused on the development of minimally invasive gastric manipulation methods featuring a safe but reliable and long-term sustainable weight loss effect similar to the one delivered by bariatric surgeries. This antiobesity approach is based on placing external devices in the stomach ranging from electrodes for gastric electrical stimulation to temporary intraluminal bezoars for gastric volume displacement for a predetermined amount of time. The present paper examines the evolution of these techniques from invasively implantable units to completely noninvasive patient-controllable implements, from a functional, rather than from the traditional, parametric point of view. Comparative discussion over the available pilot and clinical studies related to gastric electrical stimulation outlines the promises and the fallacies of this concept as a reliable alternative anti-obesity strategy. PMID:23476793

  10. Effectiveness of neuromuscular electrical stimulation in the functional knee rehabilitation in soldiers

    Directory of Open Access Journals (Sweden)

    R. Castillo-Lozano

    2015-12-01

    Full Text Available 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 of the literature about NMES in physiotherapy was performed using the following electronic databases: Web of Science, PubMed, Cochrane, Physiotherapy Evidence Database (PEDro and CINAHL. The search strategy was: "neuromuscular electrical stimulation" and "physical therapy" and "strengthening" and "knee". Inclusion criteria were: original articles published and peer reviewed between 2004-2015, focusing on physiotherapy interventions by NMES on subjects older than 18 years. A total resulting from 46 studies was included in the study. Results: The results show the evidence on the effectiveness of NMES therapeutic/preventive purposes in the muscular system; and the importance of physical therapy in the army. Conclusion: As a method of functional knee rehabilitation, NMES proves effective in achieving the therapeutic/preventive objectives in soldiers. Level of Evidence: II. Systematic review of randomized clinical trials with homogeneity.

  11. Characteristics of retinal reflectance changes induced by transcorneal electrical stimulation in cat eyes.

    Directory of Open Access Journals (Sweden)

    Takeshi Morimoto

    Full Text Available Transcorneal electrical stimulation (TES activates retinal neurons leading to visual sensations. How the retinal cells are activated by TES has not been definitively determined. Investigating the reflectance changes of the retina is an established technique and has been used to determine the mechanism of retinal activation. The purpose of this study was to evaluate the reflectance changes elicited by TES in cat eyes. Eight eyes of Eight cats were studied under general anesthesia. Biphasic electrical pulses were delivered transcornealy. The fundus images observed with near-infrared light (800-880 nm were recorded every 25 ms for 26 s. To improve the signal-to-noise ratio, the images of 10 consecutive recordings were averaged. Two-dimensional topographic maps of the reflective changes were constructed by subtracting images before from those after the TES. The effects of different stimulus parameters, e.g., current intensity, pulse duration, frequency, and stimulus duration, on the reflective changes were studied. Our results showed that after TES, the reflective changes appeared on the retinal vessels and optic disc. The intensity of reflectance changes increased as the current intensity, pulse duration, and stimulation duration increased (P<0.05 for all. The maximum intensity of the reflective change was obtained when the stimulus frequency was 20 Hz. The time course of the reflectance changes was also altered by the stimulation parameters. The response started earlier and returned to the baseline later with higher current intensities, longer pulse durations, but the time of the peak of the response was not changed. These results showed that the reflective changes were due to the activation of retinal neurons by TES and might involve the vascular changes induced by an activation of the retinal neurons.

  12. Effect of 3 postmortem electrical stimulation treatments on the quality of early deboned broiler breast meat.

    Science.gov (United States)

    Zhuang, H; Savage, E M; Lawrence, K

    2010-08-01

    The present experiment was carried out to evaluate the effects of electrical stimulation (ES) immediately prescalding (PS), ES immediately postdefeathering (PD), or PS combined with PD (PSPD) on the quality of early deboned (2 h) broiler breast muscles, pectoralis major (fillets), and pectoralis minor (tenders). No stimulation, early-deboned (2 h), and 24-h deboned (24 h) fillets were used for the comparison. The 42-d-old broiler carcasses were electrically stimulated with pulsed current at 200 V for 30 s over a 90-s time interval (total of 1 min over 180 s for PSPD), and breast meat was deboned 2 h postmortem. Quality indicators evaluated were CIE L*, a*, and b* color and pH of the raw fillets and cook yields and Warner-Bratzler (WB) shear force of the fillets and tenders. There were no differences in raw fillet color, pH, and cook yields of both the fillets and tenders between the 3 ES treatments. Effects of different ES treatments on meat WB shear force values varied with breast muscles. For the fillets, the average WB shear force values of both the PS and PSPD samples, which were not different from each other, were significantly lower than those of the PD samples. For the tenders, there were no differences in the average shear force values between the 3 ES treatments. Regardless of ES treatment and breast muscle, early deboned broiler breast meat from ES carcasses required significantly less force to shear than the 2-h control. These results indicate that ES can tenderize early deboned poultry breast muscles; however, the effectiveness of ES tenderization varies with ES treatments for the fillets. The PS treatment is more effective in reducing fillet shear values than PD, and there is no further reduction in shear values with PSPD compared with the PS treatment. PMID:20634531

  13. Gastric electrical stimulation for gastroparesis: A goal greatly pursued, but not yet attained

    Institute of Scientific and Technical Information of China (English)

    Mauro Bortolotti

    2011-01-01

    The lack of an effective medical treatment for gastroparesis has pushed the research of new techniques of gastric electrical stimulation (GES) for nearly half a century of experimentation with a large variety of electrical stimuli delivered to the gastric wall of animals and patients with gastroparesis. Three principal methods are currently available: gastric low-frequency/high-energy GES with long pulse stimulation, high-frequency/lowenergy GES with short pulse stimulation and neural sequential GES. The first method aims to reset a regular slow wave rhythm, but has variable effects on contractions and requires devices with large and heavy batteries unsuitable for implantation. High-frequency/lowenergy GES, although inadequate to restore a normal gastric electro-mechanical activity, improves dyspeptic symptoms, such as nausea and vomiting, giving patients a better quality of life together with a more satisfactory nutritional status and is suitable for implantation. Unfortunately, the numerous clinical studies using this type of GES, with the exception of two, were not controlled and there is a need for definitive verification of the effectiveness of this technique to justify the cost and the risks of this procedure. The last method, which is neural sequential GES, consists of a microprocessor-controlled sequential activation of a series of annular electrodes along the distal two thirds of the stomach and is able to induce propagated contractions causing forceful emptying of the gastric content. The latter method is the most promising, but has been used only in animals and needs to be tested in patients with gastroparesis before it is regarded as a solution for this disease.

  14. Compression Stockings versus Neuromuscular Electrical Stimulation Devices in the Management of Occupational Leg Swelling.

    Science.gov (United States)

    Wou, J; Williams, K J; Davies, A H

    2016-06-01

    Background Occupational edema is reported to occur in healthy individuals after working in a sitting or standing position for extensive periods of time. It can be associated with feelings of tiredness, heaviness of the legs, and pain. Three licensed medical devices were compared in their management of occupational edema. Subjects and Methods A total of 10 subjects were recruited from a clinical workspace. Right leg volume and great saphenous vein diameter was measured in the morning, and 6 hours later. On subsequent separate days, grade 2 graduated compression stockings (Active Compression Socks, Mediven, United Kingdom), geko (Firstkind Ltd, United Kingdom), and Revitive (Actegy Ltd, United Kingdom) were used bilaterally according to manufacturer's instructions. Results Leg volumes increased by median 41 mL (p < 0.05) with no intervention. Percentage increase in leg volume was found to be significantly reduced by stockings compared with control (-1.7%, p < 0.01), and were more effective than electrical devices. Changes in vein diameter poorly correlate with leg volume changes. Conclusion Occupational edema can occur over as little as 6 hours. All devices were well tolerated and reduced leg swelling. Stockings were the only device to significantly reduce leg swelling in this small trial. PMID:27231426

  15. Enhancement of differentiation and mineralisation of osteoblast-like cells by degenerate electrical waveform in an in vitro electrical stimulation model compared to capacitive coupling.

    Directory of Open Access Journals (Sweden)

    Michelle Griffin

    Full Text Available Electrical stimulation (ES is effective in enhancing bone healing, however the best electrical waveform, mode of application and mechanisms remains unclear. We recently reported the in vitro differential healing response of a novel electrical waveform called degenerate sine wave (DW compared to other forms of ES. This study further explores this original observation on osteoblast cells. Here, we electrically stimulated SaOS-2 osteoblast-like cells with DW in an in vitro ES chamber (referred to as 'DW stimulation' and compared the intracellular effects to capacitive coupling (CC stimulation. ES lasted for 4 h, followed by an incubation period of 20 h and subsequent ES for 4 additional hours. Cytotoxicity, proliferation, differentiation and mineralisation of the osteoblast-like cells were evaluated to determine the cell maturation process. DW significantly enhanced the differentiation of cells when compared to CC stimulation with increased alkaline phosphatase and collagen I gene expression by quantitative real time- polymerase chain reaction analysis (p<0.01. Moreover, DW significantly increased the mineralisation of cells compared to CC stimulation. Furthermore the transcription of osteocalcin, osteonectin, osteopontin and bone sialoprotein (p<0.05 was also up regulated by DW. However, ES did not augment the proliferation of cells. Translational analysis by immunocytochemistry and Western blotting showed increased collagen I, osteocalcin and osteonectin expression after DW than CC stimulation. In summary, we have demonstrated for the first time that DW stimulation in an in vitro ES chamber has a significant effect on maturation of osteoblast-like cells compared to CC stimulation of the same magnitude.

  16. A single session of neuromuscular electrical stimulation does not augment postprandial muscle protein accretion.

    Science.gov (United States)

    Dirks, Marlou L; Wall, Benjamin T; Kramer, Irene Fleur; Zorenc, Antoine H; Goessens, Joy P B; Gijsen, Annemie P; van Loon, Luc J C

    2016-07-01

    The loss of muscle mass and strength that occurs with aging, termed sarcopenia, has been (at least partly) attributed to an impaired muscle protein synthetic response to food intake. Previously, we showed that neuromuscular electrical stimulation (NMES) can stimulate fasting muscle protein synthesis rates and prevent muscle atrophy during disuse. We hypothesized that NMES prior to protein ingestion would increase postprandial muscle protein accretion. Eighteen healthy elderly (69 ± 1 yr) males participated in this study. After a 70-min unilateral NMES protocol was performed, subjects ingested 20 g of intrinsically l-[1-(13)C]phenylalanine-labeled casein. Plasma samples and muscle biopsies were collected to assess postprandial mixed muscle and myofibrillar protein accretion as well as associated myocellular signaling during a 4-h postprandial period in both the control (CON) and stimulated (NMES) leg. Protein ingestion resulted in rapid increases in both plasma phenylalanine concentrations and l-[1-(13)C]phenylalanine enrichments, which remained elevated during the entire 4-h postprandial period (P 0.05). In agreement, no differences were observed in the postprandial rise in myofibrillar protein bound l-[1-(13)C]phenylalanine enrichments between the CON and NMES legs (0.0115 ± 0.0014 vs. 0.0133 ± 0.0013 MPE, respectively, P > 0.05). Significant increases in mTOR and P70S6K phosphorylation status were observed in the NMES-stimulated leg only (P food intake does not augment postprandial muscle protein accretion in healthy older men. PMID:27279248

  17. Safety and Feasibility of Intermittent Electrical Stimulation for the Prevention of Deep Tissue Injury

    Science.gov (United States)

    Ahmetović, Alisa; Mushahwar, Vivian K.; Sommer, Ryan; Schnepf, Dana; Kawasaki, Lisa; Warwaruk-Rogers, Robyn; Barlott, Tim; Chong, Su Ling; Isaacson, Glen; Kim, Seoyoung; Ferguson-Pell, Martin; Stein, Richard B.; Ho, Chester; Dukelow, Sean; Chan, K. Ming

    2015-01-01

    Objective: To investigate the safety, feasibility, and acceptability of a novel treatment, intermittent electrical stimulation (IES), for preventing deep tissue injury (DTI) in different healthcare settings. Approach: Testing was conducted in an acute rehabilitation unit of a general hospital, a tertiary rehabilitation hospital, a long-term care facility, and homecare (HC). IES was delivered through surface electrodes placed either directly on the gluteal muscles or through mesh panels inside a specialized garment. Study participants at risk for DTI used the system for an average of 4 weeks. Outcome measures included skin reaction to long-term stimulation, demands on the caregiver, stability of induced muscle contraction, and acceptability as part of the users' daily routine. Results: A total of 48 study participants used the IES system. The system proved to be safe and feasible in all four clinical settings. No pressure ulcers were observed in any of the participants. There was no difference between the clinical settings in patient positioning, ease of finding optimal stimulation site, and patient acceptance. Although donning and doffing time was longer in the long-term care and HC settings than the acute rehabilitation unit and tertiary rehabilitation facility, time required to apply the IES system was <18 min (including data collection). The patients and caregivers did not find the application disruptive and indicated that the stimulation was acceptable as part of their daily routine in over 97% of the time. Innovation and Conclusion: We demonstrated the safety, feasibility, and acceptability of a novel method of IES to prevent DTI in a continuum of healthcare settings. PMID:25785240

  18. Optical and electrical stimulation of the rat prostate cavernous nerves: priming and fatigue studies

    Science.gov (United States)

    Kaouk, Ghallia S.; Perkins, William C.; Lagoda, Gwen A.; Burnett, Arthur L.; Fried, Nathaniel M.

    2015-02-01

    Optical nerve stimulation (ONS) is being explored as an alternative to electrical nerve stimulation (ENS) for use as an intra-operative diagnostic method for identification and preservation of prostate cavernous nerves (CNs) during radical prostatectomy. Nerve priming and fatigue studies were performed to further characterize CNs and provide insight into the different ONS and ENS mechanisms. ONS studies were conducted using a 1455-nm diode laser, coupled to fiber optic probe, and delivering a collimated, 1-mm-diameter laser spot on CNs. For nerve priming studies, laser power was escalated in 5 mW increments (15 - 60 mW) with each stimulation lasting 15 s, until a strong ICP response was observed, and then power was similarly de-escalated. For ONS fatigue studies, a constant laser power was delivered for a period of 10 min. ENS studies were conducted for comparison, with standard parameters (4 V, 5 ms, 16 Hz) for fatigue studies (10 min. duration), but incrementally increasing/decreasing voltage (0.1 - 4.0 V) for priming studies with 15 s stimulations. ONS threshold was approximately 20% higher during initial escalating laser power steps (6.4 W/cm2) than in subsequently de-escalating laser power steps (5.1 W/cm2), demonstrating a nerve priming effect. Evidence of nerve priming during ENS was not observed. For nerve fatigue studies, ONS of CNs showed a peak ICP response at about 60 s, followed by a gradual decay in ICP, while ENS maintained a strong, but cyclical ICP. Nerve priming may allow repetitive ONS of CNs at lower and hence safer laser power settings. Both nerve priming and fatigue studies revealed different mechanisms for ONS and ENS.

  19. The effect of electrode return configuration on multi-unit activity of the visual cortex from supra choroidal electrical stimulation

    International Nuclear Information System (INIS)

    Full text: To compare differences in thresholds and spatial selec tivity of various electrode return configurations using multi-unit cortical activity in response to electrical stimulation of a supracho roidal retinal prosthesis. Methods A polyimide substrate flexible platinum electrode array was inserted into the suprachoroidal space of normally sighted anaesthe tised cats (n 8). lndividual electrodes were electrically stimulated with biphasic, cathodic first CUITent pulses (500 lS per phase, 0-725 pAl using monopolar, hexagonal and common ground stimulation. Multi-unit activity was recorded with a 32-channel array inserted into the exposed primary visual cortex. Results Both, monopolar and hexagonal stimulation elicited cortical activity with significantly lower thresholds (monopolar, 69 27 nC; hexagonal, 86 15 nC) than common ground stimulation (J 53 15 nC), however no significant difference was found between the thresholds for monopolar and hexagonal stimulation (One way RM-ANOYA, p < 0.00 I; Pairwise multiple comparisons, Tukey test). Further, cortical thresholds increased by 58 nC for the mon polar return, 79 nC for the hexagonal return, and II nC for the common ground return for every I mm change in retinal stimulating position from the retinal position that elicited the lowest cortical threshold. Conclusion A successful retinal prosthesis will need to produce discrete phosphenes at charge levels which will not harm the retina or the stimulating electrodes. Our data shows that hexagonal stimulation is efficient in inducing cortical activity both with lower charge thresholds and a higher degree of spatial selectivity compared to monopolar and common ground stimulation. Our results suggest that hexagonal stimulation is the ideal mode of stimulation for a retinal prosthesis.

  20. Electrical stimulation of the isolated rat intestine in the presence of nutrient stimulus enhances glucagon-like peptide-1 release

    International Nuclear Information System (INIS)

    The release of small intestinal hormones by constituents of ingested food, such as fatty acids, is integral to post-prandial responses that reduce food intake. Recent evidence suggests that small intestinal electrical stimulation reduces food intake, although the mechanism of action is debated. To test the hypothesis that intestinal stimulation directly alters hormone release locally we used isolated rat distal ileum and measured glucagon-like peptide-1 (GLP-1) released in the presence or absence of linoleic acid (LA) and electrical field stimulation (EFS). Intact segments were oriented longitudinally between bipolar stimulating electrodes in organ bath chambers containing modified Krebs–Ringers bicarbonate (KRB) buffer including protease inhibitors. Incubation in LA (3 mg ml−1) for 45 min increased GLP-1 concentration (21.9 ± 2.6 pM versus KRB buffer alone 3.6 ± 0.1 pM). Eleven electrical stimulation conditions were tested. In the presence of LA none of the stimulation conditions inhibited LA-evoked GLP-1 release, whereas two high frequency short pulse widths (14 V, 20 Hz, 5 ms and 14 V, 40 Hz, 5 ms) and one low frequency long pulse width (14 V, 0.4 Hz, 300 ms) EFS conditions enhanced LA-evoked GLP-1 release by >250%. These results are consistent with a local effect of intestinal electrical stimulation to enhance GLP-1 release in response to luminal nutrients in the intestines. Enhancing hormone release could improve the efficacy of intestinal electrical stimulation and provide a potential treatment for obesity and metabolic conditions

  1. Final Report: Electric Power for India: A US-India Bilateral Study, January 1, 1998 - September 30, 1999

    Energy Technology Data Exchange (ETDEWEB)

    Arunachalam, V. S.; Morgan, Granger

    1999-12-01

    The objective of this project is to study and evaluate various technology and policy options for improving the availability of electric power in India. This project was carried out in collaboration with a number of Indian experts who participated in a joint Indo-US meeting at the University of Warwick, UK, in September 1999. This group made recommendations on capital and finance, technology, and policy initiatives for Indian and US planners to consider. These recommendations are summarized in the report.

  2. Analyzing the tradeoff between electrical complexity and accuracy in patient-specific computational models of deep brain stimulation

    Science.gov (United States)

    Howell, Bryan; McIntyre, Cameron C.

    2016-06-01

    Objective. Deep brain stimulation (DBS) is an adjunctive therapy that is effective in treating movement disorders and shows promise for treating psychiatric disorders. Computational models of DBS have begun to be utilized as tools to optimize the therapy. Despite advancements in the anatomical accuracy of these models, there is still uncertainty as to what level of electrical complexity is adequate for modeling the electric field in the brain and the subsequent neural response to the stimulation. Approach. We used magnetic resonance images to create an image-based computational model of subthalamic DBS. The complexity of the volume conductor model was increased by incrementally including heterogeneity, anisotropy, and dielectric dispersion in the electrical properties of the brain. We quantified changes in the load of the electrode, the electric potential distribution, and stimulation thresholds of descending corticofugal (DCF) axon models. Main results. Incorporation of heterogeneity altered the electric potentials and subsequent stimulation thresholds, but to a lesser degree than incorporation of anisotropy. Additionally, the results were sensitive to the choice of method for defining anisotropy, with stimulation thresholds of DCF axons changing by as much as 190%. Typical approaches for defining anisotropy underestimate the expected load of the stimulation electrode, which led to underestimation of the extent of stimulation. More accurate predictions of the electrode load were achieved with alternative approaches for defining anisotropy. The effects of dielectric dispersion were small compared to the effects of heterogeneity and anisotropy. Significance. The results of this study help delineate the level of detail that is required to accurately model electric fields generated by DBS electrodes.

  3. BILATERAL OVARIAN TORSION: A CASE REPORT

    OpenAIRE

    Manohar; Gopalakrishna; Kavyashree; Kala; Karthik

    2014-01-01

    : Bilateral ovarian torsion is a rare event with only a few cases reported in literature in women using ovarian stimulation drugs and in pre-menarchal age group with synchronous and asynchronous ovarian tumors. We hereby present a case of bilateral ovarian torsion in a 16 year old girl who presented as an acute pain abdomen and was diagnosed intra operatively.

  4. Electrical stimulation as a biomimicry tool for regulating muscle cell behavior.

    Science.gov (United States)

    Ahadian, Samad; Ostrovidov, Serge; Hosseini, Vahid; Kaji, Hirokazu; Ramalingam, Murugan; Bae, Hojae; Khademhosseini, Ali

    2013-01-01

    There is a growing need to understand muscle cell behaviors and to engineer muscle tissues to replace defective tissues in the body. Despite a long history of the clinical use of electric fields for muscle tissues in vivo, electrical stimulation (ES) has recently gained significant attention as a powerful tool for regulating muscle cell behaviors in vitro. ES aims to mimic the electrical environment of electroactive muscle cells (e.g., cardiac or skeletal muscle cells) by helping to regulate cell-cell and cell-extracellular matrix (ECM) interactions. As a result, it can be used to enhance the alignment and differentiation of skeletal or cardiac muscle cells and to aid in engineering of functional muscle tissues. Additionally, ES can be used to control and monitor force generation and electrophysiological activity of muscle tissues for bio-actuation and drug-screening applications in a simple, high-throughput, and reproducible manner. In this review paper, we briefly describe the importance of ES in regulating muscle cell behaviors in vitro, as well as the major challenges and prospective potential associated with ES in the context of muscle tissue engineering. PMID:23823664

  5. The influence of sulcus width on simulated electric fields induced by transcranial magnetic stimulation

    International Nuclear Information System (INIS)

    Volume conduction models can help in acquiring knowledge about the distribution of the electric field induced by transcranial magnetic stimulation. One aspect of a detailed model is an accurate description of the cortical surface geometry. Since its estimation is difficult, it is important to know how accurate the geometry has to be represented. Previous studies only looked at the differences caused by neglecting the complete boundary between cerebrospinal fluid (CSF) and grey matter (Thielscher et al 2011 NeuroImage 54 234–43, Bijsterbosch et al 2012 Med. Biol. Eng. Comput. 50 671–81), or by resizing the whole brain (Wagner et al 2008 Exp. Brain Res. 186 539–50). However, due to the high conductive properties of the CSF, it can be expected that alterations in sulcus width can already have a significant effect on the distribution of the electric field. To answer this question, the sulcus width of a highly realistic head model, based on T1-, T2- and diffusion-weighted magnetic resonance images, was altered systematically. This study shows that alterations in the sulcus width do not cause large differences in the majority of the electric field values. However, considerable overestimation of sulcus width produces an overestimation of the calculated field strength, also at locations distant from the target location. (paper)

  6. A new paradigm of electrical stimulation to enhance sensory neural function.

    Science.gov (United States)

    Breen, Paul P; ÓLaighin, Gearóid; McIntosh, Caroline; Dinneen, Sean F; Quinlan, Leo R; Serrador, Jorge M

    2014-08-01

    The ability to improve peripheral neural transmission would have significant therapeutic potential in medicine. A technology of this kind could be used to restore and/or enhance sensory function in individuals with depressed sensory function, such as older adults or patients with peripheral neuropathies. The goal of this study was to investigate if a new paradigm of subsensory electrical noise stimulation enhances somatosensory function. Vibration (50Hz) was applied with a Neurothesiometer to the plantar aspect of the foot in the presence or absence of subsensory electrical noise (1/f type). The noise was applied at a proximal site, on a defined region of the tibial nerve path above the ankle. Vibration perception thresholds (VPT) of younger adults were measured in control and experimental conditions, in the absence or presence of noise respectively. An improvement of ∼16% in VPT was found in the presence of noise. These are the first data to demonstrate that modulation of axonal transmission with externally applied electrical noise improves perception of tactile stimuli in humans. PMID:24894033

  7. Electrical stimulation of the vagus nerve protects against cerebral ischemic injury through an anti-infammatory mechanism

    Directory of Open Access Journals (Sweden)

    Yao-xian Xiang

    2015-01-01

    Full Text Available Vagus nerve stimulation exerts protective effects against ischemic brain injury; however, the underlying mechanisms remain unclear. In this study, a rat model of focal cerebral ischemia was established using the occlusion method, and the right vagus nerve was given electrical stimulation (constant current of 0.5 mA; pulse width, 0.5 ms; frequency, 20 Hz; duration, 30 seconds; every 5 minutes for a total of 60 minutes 30 minutes, 12 hours, and 1, 2, 3, 7 and 14 days after surgery. Electrical stimulation of the vagus nerve substantially reduced infarct volume, improved neurological function, and decreased the expression levels of tumor necrosis factor-and interleukin- 6 in rats with focal cerebral ischemia. The experimental findings indicate that the neuroprotective effect of vagus nerve stimulation following cerebral ischemia may be associated with the inhibition of tumor necrosis factor- and interleukin-6 expression.

  8. The effects of anodal transcranial direct current stimulation and patterned electrical stimulation on spinal inhibitory interneurons and motor function in patients with spinal cord injury.

    Science.gov (United States)

    Yamaguchi, Tomofumi; Fujiwara, Toshiyuki; Tsai, Yun-An; Tang, Shuen-Chang; Kawakami, Michiyuki; Mizuno, Katsuhiro; Kodama, Mitsuhiko; Masakado, Yoshihisa; Liu, Meigen

    2016-06-01

    Supraspinal excitability and sensory input may play an important role for the modulation of spinal inhibitory interneurons and functional recovery among patients with incomplete spinal cord injury (SCI). Here, we investigated the effects of anodal transcranial direct current stimulation (tDCS) combined with patterned electrical stimulation (PES) on spinal inhibitory interneurons in patients with chronic incomplete SCI and in healthy individuals. Eleven patients with incomplete SCI and ten healthy adults participated in a single-masked, sham-controlled crossover study. PES involved stimulating the common peroneal nerve with a train of ten 100 Hz pulses every 2 s for 20 min. Anodal tDCS (1 mA) was simultaneously applied to the primary motor cortex that controls the tibialis anterior muscle. We measured reciprocal inhibition and presynaptic inhibition of a soleus H-reflex by stimulating the common peroneal nerve prior to tibial nerve stimulation, which elicits the H-reflex. The inhibition was assessed before, immediately after, 10 min after and 20 min after the stimulation. Compared with baseline, simultaneous application of anodal tDCS with PES significantly increased changes in disynaptic reciprocal inhibition and long-latency presynaptic inhibition in both healthy and SCI groups for at least 20 min after the stimulation (all, p < 0.001). In patients with incomplete SCI, anodal tDCS with PES significantly increased the number of ankle movements in 10 s at 20 min after the stimulation (p = 0.004). In conclusion, anodal tDCS combined with PES could induce spinal plasticity and improve ankle movement in patients with incomplete SCI. PMID:26790423

  9. Different effects of transcutaneous electric nerve stimulation and electroacupuncture at ST36–ST37 on the cerebral cortex

    OpenAIRE

    Kang, Yu-Tien; Liao, Yi-Sheng; Hsieh, Ching-Liang

    2014-01-01

    Background The effects of transcutaneous electric nerve stimulation (TENS) and electroacupuncture (EA) on the cerebral cortex are largely unclear. The purpose of the present study was to investigate the effect of TENS and EA on the cerebral cortex by examining their effect on the median nerve-somatosensory evoked potentials (MN-SEPs). Methods Twenty volunteers were studied. The cortical and cervical spinal potentials were recorded by median nerve stimulation at the left wrist. Sham TENS, 2 Hz...

  10. Effects of Functional Electrical Stimulation on Gait Function and Quality of Life for People with Multiple Sclerosis Taking Dalfampridine

    OpenAIRE

    Mayer, Lori; Warring, Tina; Agrella, Stephanie; Rogers, Helen L.; Fox, Edward J.

    2015-01-01

    Background: Multiple sclerosis (MS) can adversely affect gait, causing gait slowing, loss of balance, decreased functional mobility, and gait deficits, such as footdrop. Current treatments for gait dysfunction due to MS are pharmacologic, using dalfampridine, or orthotic, using an ankle-foot orthosis. Functional electrical stimulation (FES) to the fibular nerve stimulates active dorsiflexion and provides an alternative treatment for gait dysfunction caused by footdrop. The objective of this s...

  11. A Three Spatial Dimension Wave Latent Force Model for Describing Excitation Sources and Electric Potentials Produced by Deep Brain Stimulation

    OpenAIRE

    Alvarado, Pablo A.; Álvarez, Mauricio A.; Orozco, Álvaro A.

    2016-01-01

    Deep brain stimulation (DBS) is a surgical treatment for Parkinson's Disease. Static models based on quasi-static approximation are common approaches for DBS modeling. While this simplification has been validated for bioelectric sources, its application to rapid stimulation pulses, which contain more high-frequency power, may not be appropriate, as DBS therapeutic results depend on stimulus parameters such as frequency and pulse width, which are related to time variations of the electric fiel...

  12. Control system design for electrical stimulation in upper limb rehabilitation modelling, identification and robust performance

    CERN Document Server

    Freeman, Chris

    2016-01-01

    This book presents a comprehensive framework for model-based electrical stimulation (ES) controller design, covering the whole process needed to develop a system for helping people with physical impairments perform functional upper limb tasks such as eating, grasping and manipulating objects. The book first demonstrates procedures for modelling and identifying biomechanical models of the response of ES, covering a wide variety of aspects including mechanical support structures, kinematics, electrode placement, tasks, and sensor locations. It then goes on to demonstrate how complex functional activities of daily living can be captured in the form of optimisation problems, and extends ES control design to address this case. It then lays out a design methodology, stability conditions, and robust performance criteria that enable control schemes to be developed systematically and transparently, ensuring that they can operate effectively in the presence of realistic modelling uncertainty, physiological variation an...

  13. Bioelectronic neural pixel: Chemical stimulation and electrical sensing at the same site.

    Science.gov (United States)

    Jonsson, Amanda; Inal, Sahika; Uguz, Llke; Williamson, Adam J; Kergoat, Loïg; Rivnay, Jonathan; Khodagholy, Dion; Berggren, Magnus; Bernard, Christophe; Malliaras, George G; Simon, Daniel T

    2016-08-23

    Local control of neuronal activity is central to many therapeutic strategies aiming to treat neurological disorders. Arguably, the best solution would make use of endogenous highly localized and specialized regulatory mechanisms of neuronal activity, and an ideal therapeutic technology should sense activity and deliver endogenous molecules at the same site for the most efficient feedback regulation. Here, we address this challenge with an organic electronic multifunctional device that is capable of chemical stimulation and electrical sensing at the same site, at the single-cell scale. Conducting polymer electrodes recorded epileptiform discharges induced in mouse hippocampal preparation. The inhibitory neurotransmitter, γ-aminobutyric acid (GABA), was then actively delivered through the recording electrodes via organic electronic ion pump technology. GABA delivery stopped epileptiform activity, recorded simultaneously and colocally. This multifunctional "neural pixel" creates a range of opportunities, including implantable therapeutic devices with automated feedback, where locally recorded signals regulate local release of specific therapeutic agents. PMID:27506784

  14. Morphometric data of canine sacral nerve roots with reference to electrical sacral root stimulation.

    Science.gov (United States)

    Rijkhoff, N J; Koldewijn, E L; d'Hollosy, W; Debruyne, F M; Wijkstra, H

    1996-01-01

    Experiments to investigate restoration of lower urinary tract control by electrical stimulation of the sacral nerve roots are mostly performed on dogs, yet little morphometric data (such as canine root and fiber diameter distributions) are available. The aim of this study was to acquire morphometric data of the intradural canine sacral dorsal and ventral roots (S1-S3). Cross-sections of sacral roots of two beagle dogs were analyzed using a light microscope and image processing software. The cross-sectional area of each root was measured. The diameters of the fibers and the axons in the cross-sections of the S2 and S3 roots were measured and used to construct nerve fiber diameter frequency distribution histograms. The results show a unimodal diameter distribution for the dorsal roots and a bimodal distribution for the ventral roots. In addition the average ratio g of the axon diameter to fiber diameter was calculated for each root. PMID:8732990

  15. Portable EMG devices, Biofeedback and Contingent Electrical Stimulation applications in Bruxism

    DEFF Research Database (Denmark)

    Castrillon, Eduardo

    (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 and...... characteristics make it complicated to assess bruxism using portable EMG devices. The possibility to assess bruxism like EMG activity on a portable device made it possible to use biofeedback and CES approaches in order to treat / manage bruxism. The available scientific information about CES effects on bruxism...... 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...

  16. Etofenamate and transcutaneous electrical nerve stimulation treatment of painful spinal syndromes.

    Science.gov (United States)

    Coletta, R; Maggiolo, F; Di Tizio, S

    1988-01-01

    Thirty patients suffering from painful syndromes of the spine were admitted to a randomized controlled clinical trial. They were divided into two groups and treated either with transcutaneous electrical nerve stimulation (TENS), one application every other day, for 20 days or with TENS and an ointment containing etofenamate 10% gel, 3-5 cm daily on the day of TENS therapy, and the same dose twice daily on the other days. The associated therapy achieved, when compared with TENS alone, a statistically significant better outcome. Furthermore a marked improvement of symptoms was observed in a shorter period of time. Therapy was well tolerated and in only four cases mild, self-limiting, skin reactions were observed. On the basis of these results the use of etofenamate and TENS could represent a viable alternative to systemic nonsteroidal antiinflammatory drug therapy. PMID:2972631

  17. Combined effect of electrical stimulation and blade tenderization on some bovine muscles

    Energy Technology Data Exchange (ETDEWEB)

    Raccach, M.; Henrickson, R.L.

    1979-01-01

    The electrical stimulation (ES) period was a very important factor determining the tenderness of three bovine muscles: Biceps femoris (BF), Longissimus dorsi (LD), and Semimembranosus (SM). Tenderness (shear force values) increased in most cases with increasing the ES period. An ES period of 15 min was optimal for obtaining a tenderness equal to that obtained by conventional processing of beef. The shortest ES period used (1 min) was adequate in most cases to set the muscles in rigor mortis and in preventing cold shortening. The tenderness of blade tenderized muscles was in most cases independent from the ES period. Blade tenderization was very effective to tenderize the BF muscle followed in decreasing order of efficacy by the LD and SM muscles. The cooking times and cooking losses of the three muscles were not affected by either the ES period or by blade tenderization.

  18. 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 tenderness was improved depending on voltage range used (P < 0.001). ES caused difference in instrumental colour (CIE L∗, a∗, b∗) values of lamb and goat meat compared with the control groups (P < 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. PMID:22593699

  19. Adaptive synchronization control of coupled chaotic neurons in an external electrical stimulation

    International Nuclear Information System (INIS)

    In this paper we present a combined algorithm for the synchronization control of two gap junction coupled chaotic FitzHugh—Nagumo (FHN) neurons in an external electrical stimulation. The controller consists of a combination of dynamical sliding mode control and adaptive backstepping control. The combined algorithm yields an adaptive dynamical sliding mode control law which has the advantage over static sliding mode-based controllers of being chattering-free, i.e., a sufficiently smooth control input signal is generated. It is shown that the proposed control scheme can not only compensate for the system uncertainty, but also guarantee the stability of the synchronized error system. In addition, numerical simulations are also performed to demonstrate the effectiveness of the proposed adaptive controller. (interdisciplinary physics and related areas of science and technology)

  20. Effect of hypothalamic electrical stimulation on protein synthesis in organs of adult and old rats

    International Nuclear Information System (INIS)

    Age differences in hypothalamic regulation of total protein synthesis in different organs and also of liver chromatin proteins were compared in this investigation. Rats were used in the experiments and the intensity of protein synthesis was judged from the relative specific radioactivity which was determined as the ratio of the specific radioactivities of acid-insoluble and acid-soluble materials, separated by means of nitrocellulose membrane filters. Protein was determined by two-wave spectrophotometry and the radioactivity of all samples was measured on a Mark III radio spectrometer. The investigations showed that hypothalmic electrical stimulation causes a marked increase in 3H-leucine incorporation into protein of active and inactive liver chromatin

  1. The Effect of Aging on Erectile Function Induced by Apomorphine and Electric Field Stimulation to Rat

    Institute of Scientific and Technical Information of China (English)

    李铮; 郑松; 向祖琼; 刘勇; 王益鑫

    2002-01-01

    Objective To explore the effect and mechanism of aging on erection by using ratmodel.Materials & Methods Forty male SD rats of 3, 9, 18 and 24 months old were divid-ed into 4 groups equally according to their age. Apomorphine given subcutaneously andcavernous nerve electric field stimulation was used to induce erection of rats.Results The successful erection rate, number of erection times, and intracavernouspressure (ICP) in the rats of 18 and 24 month old was significantly lower than that of3 and 9 month old.Conclusion The erectile function in aging rats is deteriorated. The damage mecha-nism with aging might be related to dopaminergic system in central nerves.

  2. Adaptive synchronization control of coupled chaotic neurons in an external electrical stimulation

    Institute of Scientific and Technical Information of China (English)

    Yu Hai-Tao; Wang Jiang; Deng Bin; Wei Xi-Le; Chen Ying-Yuan

    2013-01-01

    In this paper we present a combined algorithm for the synchronization control of two gap junction coupled chaotic FitzHugh-Nagumo (FHN) neurons in an external electrical stimulation.The controller consists of a combination of dynamical sliding mode control and adaptive backstepping control.The combined algorithm yields an adaptive dynamical sliding mode control law which has the advantage over static sliding mode-based controllers of being chattering-free,i.e.,a sufficiently smooth control input signal is generated.It is shown that the proposed control scheme can not only compensate for the system uncertainty,but also guarantee the stability of the synchronized error system.In addition,numerical simulations are also performed to demonstrate the effectiveness of the proposed adaptive controller.

  3. Application of the Actor-Critic Architecture to Functional Electrical Stimulation Control of a Human Arm.

    Science.gov (United States)

    Thomas, Philip; Branicky, Michael; van den Bogert, Antonie; Jagodnik, Kathleen

    2009-01-01

    Clinical tests have shown that the dynamics of a human arm, controlled using Functional Electrical Stimulation (FES), can vary significantly between and during trials. In this paper, we study the application of the actor-critic architecture, with neural networks for the both the actor and the critic, as a controller that can adapt to these changing dynamics of a human arm. Development and tests were done in simulation using a planar arm model and Hill-based muscle dynamics. We begin by training it using a Proportional Derivative (PD) controller as a supervisor. We then make clinically relevant changes to the dynamics of the arm and test the actor-critic's ability to adapt without supervision in a reasonable number of episodes. Finally, we devise methods for achieving both rapid learning and long-term stability. PMID:20689654

  4. Creating a Reinforcement Learning Controller for Functional Electrical Stimulation of a Human Arm.

    Science.gov (United States)

    Thomas, Philip S; Branicky, Michael; van den Bogert, Antonie; Jagodnik, Kathleen

    2008-01-01

    Clinical tests have shown that the dynamics of a human arm, controlled using Functional Electrical Stimulation (FES), can vary significantly between and during trials. In this paper, we study the application of Reinforcement Learning to create a controller that can adapt to these changing dynamics of a human arm. Development and tests were done in simulation using a two-dimensional arm model and Hill-based muscle dynamics. An actor-critic architecture is used with artificial neural networks for both the actor and the critic. We begin by training it using a Proportional Derivative (PD) controller as a supervisor. We then make clinically relevant changes to the dynamics of the arm and test the actor-critic's ability to adapt without supervision in a reasonable number of episodes. PMID:22081795

  5. Electrical stimulation of the brain and the development of cortical visual prostheses: An historical perspective.

    Science.gov (United States)

    Lewis, Philip M; Rosenfeld, Jeffrey V

    2016-01-01

    Rapid advances are occurring in neural engineering, bionics and the brain-computer interface. These milestones have been underpinned by staggering advances in micro-electronics, computing, and wireless technology in the last three decades. Several cortically-based visual prosthetic devices are currently being developed, but pioneering advances with early implants were achieved by Brindley followed by Dobelle in the 1960s and 1970s. We have reviewed these discoveries within the historical context of the medical uses of electricity including attempts to cure blindness, the discovery of the visual cortex, and opportunities for cortex stimulation experiments during neurosurgery. Further advances were made possible with improvements in electrode design, greater understanding of cortical electrophysiology and miniaturisation of electronic components. Human trials of a new generation of prototype cortical visual prostheses for the blind are imminent. This article is part of a Special Issue entitled Hold Item. PMID:26348986

  6. Mild electrical stimulation with heat shock ameliorates insulin resistance via enhanced insulin signaling.

    Directory of Open Access Journals (Sweden)

    Saori Morino

    Full Text Available Low-intensity electrical current (or mild electrical stimulation; MES influences signal transduction and activates phosphatidylinositol-3 kinase (PI3K/Akt pathway. Because insulin resistance is characterized by a marked reduction in insulin-stimulated PI3K-mediated activation of Akt, we asked whether MES could increase Akt phosphorylation and ameliorate insulin resistance. In addition, it was also previously reported that heat shock protein 72 (Hsp72 alleviates hyperglycemia. Thus, we applied MES in combination with heat shock (HS to in vitro and in vivo models of insulin resistance. Here we show that 10-min treatment with MES at 5 V (0.1 ms pulse duration together with HS at 42 degrees C increased the phosphorylation of insulin signaling molecules such as insulin receptor substrate (IRS and Akt in HepG2 cells maintained in high-glucose medium. MES (12 V+mild HS treatment of high fat-fed mice also increased the phosphorylation of insulin receptor beta subunit (IRbeta and Akt in mice liver. In high fat-fed mice and db/db mice, MES+HS treatment for 10 min applied twice a week for 12-15 weeks significantly decreased fasting blood glucose and insulin levels and improved insulin sensitivity. The treated mice showed significantly lower weight of visceral and subcutaneous fat, a markedly improved fatty liver and decreased size of adipocytes. Our findings indicated that the combination of MES and HS alleviated insulin resistance and improved fat metabolism in diabetes mouse models, in part, by enhancing the insulin signaling pathway.

  7. Transcutaneous electrical nerve stimulation in the treatment of patients with poststroke urinary incontinence

    Directory of Open Access Journals (Sweden)

    Guo ZF

    2014-05-01

    Full Text Available Zhui-feng Guo,1,* Yi Liu,2,* Guang-hui Hu,1 Huan Liu,1 Yun-fei Xu11Department of Urology, 2Department of Neurology, Shanghai Tenth People’s Hospital, Tongji University, Shanghai, People’s Republic of China*These authors contributed equally to this workPurpose: To investigate the therapeutic effect of transcutaneous electrical nerve stimulation (TENS on poststroke urinary incontinence (UI.Patients and methods: Sixty-one patients with poststroke UI were enrolled at the Neurology Department in the Shanghai Tenth People’s Hospital of Tongji University between January 2010–January 2011 and were divided into treatment and control groups (n=32 and n=29, respectively. TENS was applied to the treatment group, while the control group received basic therapy. The therapeutic group completed the whole set of TENS therapy with a treatment frequency of 30 minutes once a day for 60 days. The positive electrode was placed on the second lumbar spinous process, and the negative electrodes were inside the middle and lower third of the junction between the posterior superior iliac spine and ischia node. The overactive bladder symptom score, Barthel Index, and urodynamics examination were estimated before and after therapy in both groups.Results: The daily micturition, nocturia, urgent urination, and urge UI in the treatment group significantly improved compared to the control group (P<0.05. The patients in the treatment group were superior in the self-care ability of daily living and also had an advantage over the indexes on maximum cystometry volume, flow rate, and the pressure of detrusor in the end of the filling phase.Conclusion: TENS improved incontinence symptoms, enhanced the quality of life, and decreased adverse effects; hence, it is recommended in treating poststroke UI.Keywords: stroke, urinary incontinence, OABSS, Barthel Index, urodynamics, transcutaneous electrical nerve stimulation

  8. Evoked electromyography-based closed-loop torque control in functional electrical stimulation.

    Science.gov (United States)

    Zhang, Qin; Hayashibe, Mitsuhiro; Azevedo-Coste, Christine

    2013-08-01

    This paper proposed a closed-loop torque control strategy of functional electrical stimulation (FES) with the aim of obtaining an accurate, safe, and robust FES system. Generally, FES control systems are faced with the challenge of how to deal with time-variant muscle dynamics due to physiological and biochemical factors (such as fatigue). The degraded muscle force needs to be compensated in order to ensure the accuracy of the motion restored by FES. Another challenge concerns the fact that implantable sensors are unavailable to feedback torque information for FES in humans. As FES-evoked electromyography (EMG) represents the activity of stimulated muscles, and also enables joint torque prediction as presented in our previous studies, here we propose an EMG-feedback predictive controller of FES to control joint torque adaptively. EMG feedback contributes to taking the activated muscle state in the FES torque control system into account. The nature of the predictive controller facilitates prediction of the muscle mechanical response and the system can therefore control joint torque from EMG feedback and also respond to time-variant muscle state changes. The control performance, fatigue compensation and aggressive control suppression capabilities of the proposed controller were evaluated and discussed through experimental and simulation studies. PMID:23529189

  9. The role of membrane dynamics in electrical and infrared neural stimulation

    Science.gov (United States)

    Moen, Erick K.; Beier, Hope T.; Ibey, Bennett L.; Armani, Andrea M.

    2016-03-01

    We recently developed a nonlinear optical imaging technique based on second harmonic generation (SHG) to identify membrane disruption events in live cells. This technique was used to detect nanoporation in the plasma membrane following nanosecond pulsed electric field (nsPEF) exposure. It has been hypothesized that similar poration events could be induced by the thermal gradients generated by infrared (IR) laser energy. Optical pulses are a highly desirable stimulus for the nervous system, as they are capable of inhibiting and producing action potentials in a highly localized but non-contact fashion. However, the underlying mechanisms involved with infrared neural stimulation (INS) are not well understood. The ability of our method to non-invasively measure membrane structure and transmembrane potential via Two Photon Fluorescence (TPF) make it uniquely suited to neurological research. In this work, we leverage our technique to understand what role membrane structure plays during INS and contrast it with nsPEF stimulation. We begin by examining the effect of IR pulses on CHO-K1 cells before progressing to primary hippocampal neurons. The use of these two cell lines allows us to directly compare poration as a result of IR pulses to nsPEF exposure in both a neuron-derived cell line, and one likely lacking native channels sensitive to thermal stimuli.

  10. Role of transcutaneous electrical nerve stimulation in post-operative analgesia

    Directory of Open Access Journals (Sweden)

    Sukhyanti Kerai

    2014-01-01

    Full Text Available The use of transcutaneous electrical nerve stimulation (TENS as non-pharmacological therapeutic modality is increasing. The types of TENS used clinically are conventional TENS, acupuncture TENS and intense TENS. Their working is believed to be based on gate control theory of pain and activation of endogenous opioids. TENS has been used in anaesthesia for treatment of post-operative analgesia, post-operative nausea vomiting and labour analgesia. Evidence to support analgesic efficacy of TENS is ambiguous. A systematic search of literature on PubMed and Cochrane Library from July 2012 to January 2014 identified a total of eight clinical trials investigating post-operative analgesic effects of TENS including a total of 442 patients. Most of the studies have demonstrated clinically significant reduction in pain intensity and supplemental analgesic requirement. However, these trials vary in TENS parameters used that is, duration, intensity, frequency of stimulation and location of electrodes. Further studies with adequate sample size and good methodological design are warranted to establish general recommendation for use of TENS for post-operative pain.

  11. Particle simulation of femtosecond laser stimulation of electrical discharges in small gaps

    International Nuclear Information System (INIS)

    A particle-in-cell/Monte Carlo collision simulation study of femtosecond laser stimulation of electrical discharges in submicron gaps between platinum scanning tunneling microscope cathode tips and gold film anodes in atmospheric pressure argon gas is described. The breakdown potential of gaps containing either preloaded electrons or preloaded neutral and ionized platinum atoms and electrons at various densities were compared to the breakdown potential of gaps with background argon gas alone. It was found that gaps preloaded with sufficient densities of either electrons or partially ionized electrode materials broke down at cathode potential of -80 V while gaps with background argon gas alone required applied cathode potentials between -200 to -250 V to cause a breakdown. Also, partially ionized material was much more effective at stimulating breakdown than electrons alone. The density of preloaded partially ionized platinum required to lower breakdown cathode potential to -80 V was approximately 12.5 times smaller than that required for the preloaded electrons alone in the same size gap. Analysis of the mechanism by which the preloaded partially ionized material promoted breakdown showed that laser ablated ions located near the cathode tip increased the local field at the cathode surface and the field-emitted electron flux from the cathode. This higher electron flux ionized background argon gas and preloaded platinum which resulted in gap breakdown. The threshold density of partially ionized platinum for gap breakdown varied approximately linearly with applied cathode potential.

  12. Specific disgust processing in the left insula: New evidence from direct electrical stimulation.

    Science.gov (United States)

    Papagno, Costanza; Pisoni, Alberto; Mattavelli, Giulia; Casarotti, Alessandra; Comi, Alessandro; Fumagalli, Francesca; Vernice, Mirta; Fava, Enrica; Riva, Marco; Bello, Lorenzo

    2016-04-01

    Neuropsychological and neuroimaging studies yielded controversial results concerning the specific role of the insula in recognizing the facial expression of disgust. To verify whether the insula has a selective role in facial disgust processing, emotion recognition was studied in thirteen patients during intraoperative stimulation of the insula in awake surgery performed for removal of a glioma close to this structure. Direct electrical stimulation of the left insula produced a general decrease in emotion recognition but only in the case of disgust there was a statistically significant detrimental effect (p=0.004). Happiness and anger were the best and the worst recognized emotion, respectively. The worst baseline performance with anger and, partly, fear could be explained with the involvement of the left temporal regions, striatum, and the connection between the striatum and the frontal lobe, as suggested in previous studies. Therefore, upon these intra-operative evidences, we argue for a selective role of the left insula in disgust recognition, although a (non significant) decrease in the recognition of other negative emotions was found. However, additional networks can develop, as demonstrated by the fact that disgust recognition was not impaired after surgery even in patients with insular resection in the current as in previous studies. PMID:26836143

  13. Nanostructured Polyaniline Coating on ITO Glass Promotes the Neurite Outgrowth of PC 12 Cells by Electrical Stimulation.

    Science.gov (United States)

    Wang, Liping; Huang, Qianwei; Wang, Jin-Ye

    2015-11-10

    A conducting polymer polyaniline (PANI) with nanostructure was synthesized on indium tin oxide (ITO) glass. The effect of electrical stimulation on the proliferation and the length of neurites of PC 12 cells was investigated. The dynamic protein adsorption on PANI and ITO surfaces in a cell culture medium was also compared with and without electrical stimulation. The adsorbed proteins were characterized using SDS-PAGE. A PANI coating on ITO surface was shown with 30-50 nm spherical nanostructure. The number of PC 12 cells was significantly greater on the PANI/ITO surface than on ITO and plate surfaces after cell seeding for 24 and 36 h. This result confirmed that the PANI coating is nontoxic to PC 12 cells. The electrical stimulation for 1, 2, and 4 h significantly enhanced the cell numbers for both PANI and ITO conducting surfaces. Moreover, the application of electrical stimulation also improved the neurite outgrowth of PC 12 cells, and the number of PC 12 cells with longer neurite lengths increased obviously under electrical stimulation for the PANI surface. From the mechanism, the adsorption of DMEM proteins was found to be enhanced by electrical stimulation for both PANI/ITO and ITO surfaces. A new band 2 (around 37 kDa) was observed from the collected adsorbed proteins when PC 12 cells were cultured on these surfaces, and culturing PC 12 cells also seemed to increase the amount of band 1 (around 90 kDa). When immersing PANI/ITO and ITO surfaces in a DMEM medium without a cell culture, the number of band 3 (around 70 kDa) and band 4 (around 45 kDa) proteins decreased compared to that of PC 12 cell cultured surfaces. These results are valuable for the design and improvement of the material performance for neural regeneration. PMID:25992643

  14. [Long-term adaptation of the patients to electrical stimulation in the course of rehabilitation following cochlear implantation].

    Science.gov (United States)

    Kruglov, A V; Potalova, L A

    2014-01-01

    The objective of the present work was to study long-term adaptation of the patients to electrical stimulation in the course of rehabilitation following cochlear implantation. The following parameters were determined: variations of threshold auditory sensation of electrical stimulation (ESS), alteration of the maximum electrical stimulation comfort level (MCL), changes in the dynamic range (DR) of the stimulus and changes in the threshold auditory nerve action potentials (ANAP). The observations on ESS dynamics and DR of the stimulus were collected during 2 years after the first connection of the processor in a group of 27 patients. The data obtained from the 3rd, 12th, and 20th stimulation channels were included in the study. The observations on ANAP dynamics were collected during 1 year after surgery in a group of 112 patients. It was shown that ESS variations largely occurred within the first two weeks after connection and did not reach statistical significance. In contrast, MCL and DR changes showed a stably increasing tendency throughout the entire period of observations, with the enhancement of MCL of DR amounting to 25-28% and roughly 50% of the initial values respectively. Threshold auditory sensation of electrical stimulation significantly decreased by the time of the first connection of the implant compared with the surgical data. Further changes in threshold ESS were relatively small and did not reach statistical significance. PMID:25246204

  15. Electrical Stimulation Decreases Coupling Efficiency Between Beta-Adrenergic Receptors and Cyclic AMP Production in Cultured Muscle Cells

    Science.gov (United States)

    Young, R. B.; Bridge, K. Y.

    1999-01-01

    Electrical stimulation of skeletal muscle cells in culture is an effective way to simulate the effects of muscle contraction and its effects on gene expression in muscle cells. Expression of the beta-adrenergic receptor and its coupling to cyclic AMP synthesis are important components of the signaling system that controls muscle atrophy and hypertrophy, and the goal of this project was to determine if electrical stimulation altered the beta-adrenergic response in muscle cells. Chicken skeletal muscle cells that had been grown for seven days in culture were subjected to electrical stimulation for an additional two days at a pulse frequency of 0.5 pulses/sec and a pulse duration of 200 msec. At the end of this two-day stimulation period, beta-adrenergic receptor population was measured by the binding of tritium-labeled CGP-12177 to muscle cells, and coupling to cAMP synthesis was measured by Radioimmunoassay (RIA) after treating the cells for 10 min with the potent (beta)AR agonist, isoproterenol. The number of beta adrenergic receptors and the basal levels of intracellular cyclic AMP were not affected by electrical stimulation. However, the ability of these cells to synthesize cyclic AMP was reduced by approximately 50%. Thus, an enhanced level of contraction reduces the coupling efficiency of beta-adrenergic receptors for cyclic AMP production.

  16. Postsurgical pathologies associated with intradural electrical stimulation in the central nervous system: design implications for a new clinical device.

    Science.gov (United States)

    Gibson-Corley, Katherine N; Flouty, Oliver; Oya, Hiroyuki; Gillies, George T; Howard, Matthew A

    2014-01-01

    Spinal cord stimulation has been utilized for decades in the treatment of numerous conditions such as failed back surgery and phantom limb syndromes, arachnoiditis, cancer pain, and others. The placement of the stimulating electrode array was originally subdural but, to minimize surgical complexity and reduce the risk of certain postsurgical complications, it became exclusively epidural eventually. Here we review the relevant clinical and experimental pathologic findings, including spinal cord compression, infection, hematoma formation, cerebrospinal fluid leakage, chronic fibrosis, and stimulation-induced neurotoxicity, associated with the early approaches to subdural electrical stimulation of the central nervous system, and the spinal cord in particular. These findings may help optimize the safety and efficacy of a new approach to subdural spinal cord stimulation now under development. PMID:24800260

  17. Cranial Electrical Stimulation Potential Use in Reducing Sleep and Mood Disturbances in Persons With Dementia and Their Family Caregivers

    Science.gov (United States)

    Rose, Karen M.; Taylor, Ann Gill; Bourguignon, Cheryl; Utz, Sharon W.; Goehler, Lisa E.

    2009-01-01

    Family caregivers of persons with dementia and their care recipients frequently experience sleep and mood disturbances throughout their caregiving and disease trajectories. Because conventional pharmacologic treatments of sleep and mood disturbances pose numerous risks and adverse effects to elderly persons, the investigation of other interventions is warranted. As older adults use complementary and alternative medicine interventions for the relief of sleep and mood disturbances, cranial electrical stimulation, an energy-based complementary and alternative medicine, may be a viable intervention. The proposed mechanism of action and studies that support cranial electrical stimulation as a modality to reduce distressing symptoms are reviewed. Directions for research are proposed. PMID:18552605

  18. An in vitro model for investigating impedance changes with cell growth and electrical stimulation: implications for cochlear implants

    Science.gov (United States)

    Newbold, Carrie; Richardson, Rachael; Huang, Christie Q.; Milojevic, Dusan; Cowan, Robert; Shepherd, Robert

    2004-12-01

    The impedance of stimulating electrodes used in cochlear implants and other neural prostheses often increases post-implantation, and is thought to be due to fibrous tissue encapsulation of the electrode array. Increased impedance results in higher power requirements to stimulate target neurons at set charge densities. We developed an in vitro model to investigate the electrode-tissue interface in a highly controlled environment. This model was tested using three cell types, with and without charge-balanced biphasic electrical stimulation. Under standard tissue culture conditions, a monolayer of cells was grown over the electrode surface. Electrode impedance increased in proportion to the extent of cell coverage of the electrode. Cell type was a significant factor in the amount of impedance increase, with kidney epithelial cells (MDCK) creating the greatest impedance, followed by dissociated rat skin fibroblasts and then macrophages (J774). The application of electrical stimulation to cell-covered electrodes caused impedance fluctuations similar to that seen in vivo, with a lowering of impedance immediately following stimulation, and a recovery to pre-stimulation levels during inactive periods. Examination of these electrodes suggests that the stimulation-induced impedance changes were due to the amount of cell cover over the electrodes. This in vitro technique accurately models the changes in impedance observed with neural prostheses in vivo, and shows the close relationship between impedance and tissue coverage adjacent to the electrode surface. We believe that this in vitro approach holds great promise to further our knowledge of the mechanisms contributing to electrode impedance.

  19. Phenomenon of non-associative learning in Hering-Breuer reflex simulated by electrical vagal stimulation in rabbits.

    Science.gov (United States)

    Wang, Gui-Min; Song, Gang; Zhang, Heng

    2005-08-25

    The purpose of this study was to explore learning and memory in the Hering-Breuer (HB) reflex simulated by a 60-second-long electrical stimulation of vagus nerve. The responses of phrenic nerve discharge to electrical stimulation (10-100 Hz, 20-60 muA, pulse duration 0.3 ms, for 60 s) of the vagus nerve were observed in rabbits. The results showed that 60-second-long stimulation of vagus nerve produced classic HB reflex, which is composed of two components - lung inflation reflex that is the inhibition of inspiration, and lung deflation reflex that is the facilitation of inspiration. (1) High frequency stimulation (>/=40 Hz, 60 s) of the central end of vagus nerve induced shortening of the inspiratory phase and lengthening of expiratory duration. The inhibitory effect on phrenic discharge was released gradually during sustained vagal stimulation, indicating the habituation of the inhibition. At the cessation of stimulation, the phrenic discharge showed transient post-stimulus rebound. Low frequency stimulation (end of vagus nerve caused an increase in respiratory frequency (f) and shortening of expiratory duration. The excitatory effect on phrenic discharge was also released gradually during the vagal stimulation. The phrenic discharge returned to control level gradually after the removal of the vagal stimulus, indicating short-term potentiation (STP). (2) The habituation of HB reflex was inversely dependent on stimulus intensity and frequency. With an increase in the stimulus frequency or intensity, the degree of the habituation decreased. On the other hand, with the decrease of stimulation intensity and frequency, the degree of the habituation increased. These data indicate a phenomenon of non-associative learning in HB reflex simulated by vagal stimulation. Neural synaptic plasticity and accommodation may exist in the reflex control of respiration in rabbits. PMID:16094501

  20. Dual-channel functional electrical stimulation improvements in speed-based gait classifications

    Directory of Open Access Journals (Sweden)

    Springer S

    2013-02-01

    Full Text Available Shmuel Springer,1,2 Yocheved Laufer,1 Meni Becher,1,2 Jean-Jacques Vatine3,41Department of Physical Therapy, Faculty of Social Welfare and Health Sciences, University of Haifa, Haifa, 2Clinical Department, Bioness Neuromodulation, Ra'anana, 3Outpatient and Research Division, Reuth Medical Center, Tel Aviv, 4Department of Rehabilitation Medicine, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, IsraelBackground: Functional electrical stimulation (FES is becoming an accepted treatment method for enhancing gait performance in patients who present with gait difficulties resulting from hemiparesis. The purpose of this study was to test whether individuals with hemiparesis who have varied gait speeds, which place them in different functional categories, benefit to the same extent from the application of FES.Methods: Thirty-six subjects with chronic hemiparesis demonstrating foot-drop and deficits in knee and/or hip control were fitted with a dual-channel FES system activating the dorsiflexors and hamstring muscles. Gait was assessed during a 2-minute walk test with and without stimulation. A second assessment was conducted after 6 weeks of daily use. Analysis was performed with the subjects stratified into three functional ambulation classes according to their initial gait categories.Results: The dual-channel FES improved the gait velocity of all three subgroups. No minimal gait velocity was required in order to gain benefits from FES. For example, subjects with limited household ambulation capabilities improved their gait speed by 63.3% (from 0.30 ± 0.09 m/sec to 0.49 ± 0.20 m/sec; P < 0.01, while subjects with functional community ambulation capabilities improved their gait speed by 25.5% (from 0.90 ± 0.11 m/sec to 1.13 ± 0.22 m/sec; P < 0.01.Conclusion: Dual-channel FES positively affects gait velocity in patients with chronic hemiparesis, regardless of their initial gait velocity. Furthermore, gait velocity gains may be large enough

  1. A simple method for EEG guided transcranial electrical stimulation without models

    Science.gov (United States)

    Cancelli, Andrea; Cottone, Carlo; Tecchio, Franca; Truong, Dennis Q.; Dmochowski, Jacek; Bikson, Marom

    2016-06-01

    Objective. There is longstanding interest in using EEG measurements to inform transcranial Electrical Stimulation (tES) but adoption is lacking because users need a simple and adaptable recipe. The conventional approach is to use anatomical head-models for both source localization (the EEG inverse problem) and current flow modeling (the tES forward model), but this approach is computationally demanding, requires an anatomical MRI, and strict assumptions about the target brain regions. We evaluate techniques whereby tES dose is derived from EEG without the need for an anatomical head model, target assumptions, difficult case-by-case conjecture, or many stimulation electrodes. Approach. We developed a simple two-step approach to EEG-guided tES that based on the topography of the EEG: (1) selects locations to be used for stimulation; (2) determines current applied to each electrode. Each step is performed based solely on the EEG with no need for head models or source localization. Cortical dipoles represent idealized brain targets. EEG-guided tES strategies are verified using a finite element method simulation of the EEG generated by a dipole, oriented either tangential or radial to the scalp surface, and then simulating the tES-generated electric field produced by each model-free technique. These model-free approaches are compared to a ‘gold standard’ numerically optimized dose of tES that assumes perfect understanding of the dipole location and head anatomy. We vary the number of electrodes from a few to over three hundred, with focality or intensity as optimization criterion. Main results. Model-free approaches evaluated include (1) voltage-to-voltage, (2) voltage-to-current; (3) Laplacian; and two Ad-Hoc techniques (4) dipole sink-to-sink; and (5) sink to concentric. Our results demonstrate that simple ad hoc approaches can achieve reasonable targeting for the case of a cortical dipole, remarkably with only 2–8 electrodes and no need for a model of the head

  2. Comparative study of chemo-electro-mechanical transport models for an electrically stimulated hydrogel

    International Nuclear Information System (INIS)

    The main objective of this work is to introduce a new expression for the hydrogel’s hydration for use within the Poisson Nernst–Planck chemo electro mechanical (PNP CEM) transport models. This new contribution to the models support large deformation by considering the higher order terms in the Green–Lagrangian strain tensor. A detailed discussion of the CEM transport models using Poisson Nernst–Planck (PNP) and Poisson logarithmic Nernst–Planck (PLNP) equations for chemically and electrically stimulated hydrogels will be presented. The assumptions made to simplify both CEM transport models for electric field application in the order of 0.833 kV m−1 and a highly diluted electrolyte solution (97% is water) will be explained. This PNP CEM model has been verified accurately against experimental and numerical results. In addition, different definitions for normalizing the parameters are used to derive the dimensionless forms of both the PNP and PLNP CEM. Four models, PNP CEM, PLNP CEM, dimensionless PNP CEM and dimensionless PNLP CEM transport models were employed on an axially symmetric cylindrical hydrogel problem with an aspect ratio (diameter to thickness) of 175:3. The displacement and osmotic pressure obtained for the four models are compared against the variation of the number of elements for finite element analysis, simulation duration and solution rate when using the direct numerical solver. (papers)

  3. Microsoft Kinect-Based Artificial Perception System for Control of Functional Electrical Stimulation Assisted Grasping

    Directory of Open Access Journals (Sweden)

    Matija Štrbac

    2014-01-01

    Full Text Available We present a computer vision algorithm that incorporates a heuristic model which mimics a biological control system for the estimation of control signals used in functional electrical stimulation (FES assisted grasping. The developed processing software acquires the data from Microsoft Kinect camera and implements real-time hand tracking and object analysis. This information can be used to identify temporal synchrony and spatial synergies modalities for FES control. Therefore, the algorithm acts as artificial perception which mimics human visual perception by identifying the position and shape of the object with respect to the position of the hand in real time during the planning phase of the grasp. This artificial perception used within the heuristically developed model allows selection of the appropriate grasp and prehension. The experiments demonstrate that correct grasp modality was selected in more than 90% of tested scenarios/objects. The system is portable, and the components are low in cost and robust; hence, it can be used for the FES in clinical or even home environment. The main application of the system is envisioned for functional electrical therapy, that is, intensive exercise assisted with FES.

  4. Biphasic electrical currents stimulation promotes both proliferation and differentiation of fetal neural stem cells.

    Directory of Open Access Journals (Sweden)

    Keun-A Chang

    Full Text Available The use of non-chemical methods to differentiate stem cells has attracted researchers from multiple disciplines, including the engineering and the biomedical fields. No doubt, growth factor based methods are still the most dominant of achieving some level of proliferation and differentiation control--however, chemical based methods are still limited by the quality, source, and amount of the utilized reagents. Well-defined non-chemical methods to differentiate stem cells allow stem cell scientists to control stem cell biology by precisely administering the pre-defined parameters, whether they are structural cues, substrate stiffness, or in the form of current flow. We have developed a culture system that allows normal stem cell growth and the option of applying continuous and defined levels of electric current to alter the cell biology of growing cells. This biphasic current stimulator chip employing ITO electrodes generates both positive and negative currents in the same culture chamber without affecting surface chemistry. We found that biphasic electrical currents (BECs significantly increased the proliferation of fetal neural stem cells (NSCs. Furthermore, BECs also promoted the differentiation of fetal NSCs into neuronal cells, as assessed using immunocytochemistry. Our results clearly show that BECs promote both the proliferation and neuronal differentiation of fetal NSCs. It may apply to the development of strategies that employ NSCs in the treatment of various neurodegenerative diseases, such as Alzheimer's and Parkinson's diseases.

  5. The effect of Functional Electric Stimulation in stroke patients' motor control - a case report

    International Nuclear Information System (INIS)

    Functional Electric Stimulation (FES) has been studied as a therapeutic resource to reduce spasticity in hemiplegic patients, however there are no studies about the effects of FES in motor control of these patients during functional tasks like balance maintenance. Muscular activation of gastrocnemius medialis and semitendinosus was investigated in both limbs of a hemiparetic patient during self-disturbed quiet stance before and after FES on tibialis anterior, by surface electromyography. The instant of maximum activation peak of GM and ST were calculated immediately after a motor self-disturbance, in order to observe muscular synergy between these two muscles, and possible balance strategies used (ankle or hip strategy). At the preserved limb there occurred distal-proximal synergy (GM followed by ST), expected for small perturbations; however, at spastic limb there was inversion of this synergy (proximal-distal) after FES. It is possible that intervention of electricity had inhibited synergical pathways due to antidromic effect, making it difficult to use ankle strategy in the spastic limb.

  6. Social anxiety disorder: radio electric asymmetric conveyor brain stimulation versus sertraline

    Directory of Open Access Journals (Sweden)

    Fontani V

    2011-11-01

    Full Text Available Vania Fontani1, Piero Mannu1,2, Alessandro Castagna1, Salvatore Rinaldi11Department of Neuro Psycho Physio Pathology, Rinaldi Fontani Institute, Florence; 2Psychic Studies Center, Cagliari, ItalyPurpose: Social anxiety disorder (SAD is a disabling condition that affects almost 5% of the general population. Many types of drugs have shown their efficacy in the treatment of SAD. There are also some data regarding psychotherapies, but no data are available today about the efficacy of brain stimulation techniques. The aim of the study is to compare the efficacy of noninvasive brain stimulation neuro psycho physical optimization (NPPO protocol performed by radio electric asymmetric conveyor (REAC with that of sertraline in adults with SAD.Patients and methods: Twenty SAD patients on sertraline were compared with 23 SAD patients who refused any drug treatment and who chose to be treated with NPPO-REAC brain stimulation. This was a 6-month, open-label, naturalistic study. Patients on sertraline received flexible doses, whereas NPPO-REAC patients received two 18-session cycles of treatment. Clinical Global Improvement scale items "much improved" or "very much improved" and Liebowitz Social Anxiety Scale total score variation on fear and avoidance components were used to detect the results. The statistical analysis was performed with t-test. All measures <0.05 have been considered statistically significant.Results: Ten of 23 subjects on NPPO-REAC and six of the 20 taking sertraline were much improved or very much improved 1 month after the first NPPO-REAC cycle (t1. Sixteen of the subjects on NPPO-REAC and ten of the subjects taking sertraline were much improved or very much improved 1 month after the second NPPO-REAC cycle (t2. In respect of the Liebowitz Social Anxiety Scale, at t1 NPPO-REAC resulted in statistically more efficacy for sertraline on both fear and avoidance total scores. At t2, NPPO-REAC resulted in statistically more efficacy for

  7. Bilateral vanished testes diagnosed with a single blood sample showing very high gonadotropins (follicle-stimulating hormone and luteinizing hormone) and very low inhibin B

    DEFF Research Database (Denmark)

    Thorup, Jørgen Mogens; Petersen, Bodil Laub; Kvist, Kolja;

    2011-01-01

    Objective. In boys with cryptorchidism median serum values of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are higher and median serum values of inhibin B lower than in normal controls. Serum values of inhibin B reflect the state of germinative epithelium in cryptorchid testes....

  8. Pain Does Not Follow the Boxcar Model: Temporal Dynamics of the BOLD FMRI Signal during Constant Current Painful Electric Nerve Stimulation

    OpenAIRE

    Ibinson, JW; Vogt, KM

    2013-01-01

    The temporal dynamics of the blood oxygen level dependent (BOLD) signal, especially for painful stimulations, is not completely understood. In this study, the BOLD signal response to a long painful electrical stimulation (a continuous painful stimulation of 2 minutes) is directly compared to that of a short painful stimulation (four 30-s periods of painful stimulation interleaved with 30-s rest) in an effort to further probe the relationship between the temporal dynamics of the BOLD signal du...

  9. Optimization of multifocal transcranial current stimulation for weighted cortical pattern targeting from realistic modeling of electric fields.

    Science.gov (United States)

    Ruffini, Giulio; Fox, Michael D; Ripolles, Oscar; Miranda, Pedro Cavaleiro; Pascual-Leone, Alvaro

    2014-04-01

    Recently, multifocal transcranial current stimulation (tCS) devices using several relatively small electrodes have been used to achieve more focal stimulation of specific cortical targets. However, it is becoming increasingly recognized that many behavioral manifestations of neurological and psychiatric disease are not solely the result of abnormality in one isolated brain region but represent alterations in brain networks. In this paper we describe a method for optimizing the configuration of multifocal tCS for stimulation of brain networks, represented by spatially extended cortical targets. We show how, based on fMRI, PET, EEG or other data specifying a target map on the cortical surface for excitatory, inhibitory or neutral stimulation and a constraint on the maximal number of electrodes, a solution can be produced with the optimal currents and locations of the electrodes. The method described here relies on a fast calculation of multifocal tCS electric fields (including components normal and tangential to the cortical boundaries) using a five layer finite element model of a realistic head. Based on the hypothesis that the effects of current stimulation are to first order due to the interaction of electric fields with populations of elongated cortical neurons, it is argued that the optimization problem for tCS stimulation can be defined in terms of the component of the electric field normal to the cortical surface. Solutions are found using constrained least squares to optimize current intensities, while electrode number and their locations are selected using a genetic algorithm. For direct current tCS (tDCS) applications, we provide some examples of this technique using an available tCS system providing 8 small Ag/AgCl stimulation electrodes. We demonstrate the approach both for localized and spatially extended targets defined using rs-fcMRI and PET data, with clinical applications in stroke and depression. Finally, we extend these ideas to more general

  10. Activation of delta-type opioid receptors modulates the responses of cat terminal ileum to field electrical stimulation.

    Science.gov (United States)

    Venkova, K; Pencheva, N; Radomirov, R

    1990-01-01

    1. The effects of (D-Ala2, D-Leu5) enkephalin amide (DADLE) on the responses of the cat terminal ileum to field electrical stimulation (pulse duration of 0.5 msec, train duration of 10 sec, 30 V) were evaluated by the changes in the contractile or the relaxatory responses of longitudinal and circular strips to electrical stimuli with a frequency of 2, 10 or 30 Hz. 2. Stimulation with a frequency of 2, 10 or 30 Hz elicited contractile responses from the longitudinal strips while in the circular strips 2 Hz stimulation induced contractions and 10 or 30 Hz stimulation caused relaxation. Tetrodotoxin (TTX) (0.1 mumol/l) abolished the electrically-induced responses in both longitudinal and circular strips. 3. DADLE (1 nmol/l) significantly inhibited the cholinergic contractile responses of the longitudinal strips to 2, 10 or 30 Hz stimulation and the contractile responses of the circular strips to 2 Hz stimulation. The relaxatory responses of the circular strips to 10 or 30 Hz stimulation were insignificantly increased by DADLE. 4. On the background of guanetidine (10 mumol/l) and atropine (3 mumol/l) DADLE significantly decreased the nonadrenergic, noncholinergic relaxatory responses of the circular strips to 2, 10 or 30 Hz stimulation. 5. DADLE did not change the maximum effects and the EC50 values of acetylcholine and noradrenaline in both longitudinal and circular strips. 6. It is suggested that in the cat terminal ileum activation of delta-type opioid receptors modulates the mechanical activity suppressing the cholinergic responses in the longitudinal and circular layers as well as the adrenergic and nonadrenergic, noncholinergic responses in the circular layer. PMID:2153605

  11. Intra-operative recording of motor tract potentials at the cervico-medullary junction following scalp electrical and magnetic stimulation of the motor cortex.

    Science.gov (United States)

    Thompson, P D; Day, B L; Crockard, H A; Calder, I; Murray, N M; Rothwell, J C; Marsden, C D

    1991-07-01

    Activity in descending motor pathways after scalp electrical and magnetic brain stimulation of the motor cortex was recorded from the exposed cervico-medullary junction in six patients having trans-oral surgery of the upper cervical spine. Recordings during deep anaesthesia without muscle paralysis revealed an initial negative potential (D wave) at about 2 ms with electrical stimulation in five of the six patients. This was followed by a muscle potential which obscured any later waveforms. Magnetic stimulation produced clear potentials in only one patient. The earliest wave to magnetic stimulation during deep anaesthesia was 1-2 ms later than the earliest potential to electrical stimulation. Following lightening of the anaesthetic and the administration of muscle relaxants a series of later negative potentials (I waves) were more clearly seen to both electrical and magnetic stimulation. More I waves were recorded to magnetic stimulation during light anaesthesia than during deep anaesthesia. Increasing the intensity of electrical stimulation also produced an extra late I wave. At the highest intensity of magnetic stimulation the latency of the earliest potential was comparable to the D wave to electrical stimulation. The intervals between these various D and I waves corresponded to those previously described for the timing of single motor unit discharge after cortical stimulation. PMID:1654395

  12. Bilateral agreements

    International Nuclear Information System (INIS)

    Ten bilateral agreements are presented. These are: 1) Co-operation agreement relating to the peaceful uses of nuclear energy between Argentina and EURATOM (1996); 2) Agreement on co-operation in the peaceful uses of nuclear energy between Argentina and Greece (1997); 3) Implementing arrangement for technical exchange and co-operation in the area of peaceful uses of nuclear energy between Argentina and the United States (1997); 4) Agreement concerning co-operation in nuclear science and technology between Australia and Indonesia (1997); 5) Implementation of the 1985 Agreement for co-operation concerning the peaceful uses of nuclear energy between the People's Republic of China and the United States (1998); 6) Protocol of co-operation between France and Lithuania (1997); 7) Agreement on co-operation in energy research, science and technology, and development between Germany and the United States (1998); 8) Agreement on early notification of a nuclear accident and exchange of information on nuclear facilities between Greece and Romania (1997); 9) Agreement on early notification of nuclear accidents and co-operation in the field of nuclear safety between Hungary and the Ukraine (1997); 10) Agreement in the field of radioactive waste management between Switzerland and the United States (1997). (K.A.)

  13. Effects of various frequency electrical stimulation of the dorsal raphe nucleus on spontaneous firing activities in the rat subthalamic nucleus

    Institute of Scientific and Technical Information of China (English)

    Hongmei Ran; Dongming Gao

    2008-01-01

    BACKGROUND: Some investigations have demonstrated that exogenous 5-hydroxytryptamine increases the spontaneous firing rate of subthalamic nucleus (STN) neurons in the rat brain.OBJECTIVE: To validate the effect of electrical stimulation to the dorsal raphe nucleus (DRN) on the neu-ronal activities of the STN in rats, as well as analyze the differences in the effects of electrical stimulation at various frequencies.DESIGN, TIME AND SETTING: Experiments were performed from March 2007 to June 2007 in the Electrophysiology Laboratory of Liaoning Medical University with a randomized controlled animal study design.MATERIALS: Twenty-four healthy male Sprague-Dawley (SD) rats, weighing 250-350 g, were selected for this study. An A320R constant electrical stimulator was purchased from World Precision Instruments Com-pany (USA); a Spike 2 biological signal acquisition system was purchased from British CED Company. METHODS: Twenty-four SD rats were randomly assigned into a model group and a normal group, with 12 rats in each group. To mimic Parkinson's disease, rats in the model group were injected with 4 μL of 6-hydroxydopamine into the right striatum, then received deep brain stimulation. Rats in the normal group re-ceived deep brain stimulation in same brain region without modeling. Electrical stimulation (width, 0.06 ms; intensity, 0.2-0.6 mA; frequency, 20-130 Hz; train duration, 5 seconds) was delivered to the DRN. MAIN OUTCOME MEASURES: The firing rates of STN neurons were observed by extracellular record-ing using a biological signal acquisition system. RESULTS: DRN-high-frequency stimulation (DRN-HFS) induced excitation in 59% of the STN neurons in the normal group and 50% of the STN neurons in the model group; mean firing rates increased significantly from (7.14± 0.75) and (7.94 ± 0.61) Hz to (11.17 ± 1.49) and (12.11 ± 1.05) Hz, respectively (P < 0.01). Spontaneous firing rate increased significantly in 53% of neurons in normal rats in a frequency

  14. Effects of remifentanil on intracellular Ca2+ and its transients induced by electrical stimulation and caffeine in rat ventricular myocytes

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ye; Michael G. Irwin; LI Rui; CHEN Zhiwu; Tak-Ming Wong

    2009-01-01

    Background Preconditioning with remifentanil confers cardioprotection. Since Ca2+ overload is a precipitating factor of injury, we determined the effects of remefentanil on intracellular Ca2+ ([Ca2+]I) and its transients induced by electrical stimulation and caffeine, which reflects Ca2+ handling by Ca2+ handling proteins, in rat ventricular myocytes. Methods Freshly isolated adult male Sprague-Dawley rat myocytes were loaded with Fura-2/AM and [Ca]I was determined by spectrofluorometry. Remifentanil at 0.1-1000 μg/L was administered. Ten minutes after administration, either 0.2 Hz electrical stimulation was applied or 10 mmol/L caffeine was added. The [Ca2+]I, and the amplitude, time resting and 50% decay (t50) of both transients induced by electrical stimulation (E[Ca2+]I) and caffeine (C[Ca2+]I) were determined.Results Remifentanil (0.1-1000.0 μg/L) decreased the [Ca2+]I in a dose-dependent manner. It also decreased the amplitude of both transients dose-dependently. Furthermore, it increased the time to peak and t50 of both transients dose-dependently.Conclusion Remifentanil reduced the [Ca2+]I and suppressed the transients induced by electrical stimulation and caffeine in rat ventricular myocytes.

  15. Acupuncture and transcutaneous electric nerve stimulation in the treatment of pain associated with chronic pancreatitis. A randomized study

    DEFF Research Database (Denmark)

    Ballegaard, Søren; Christophersen, S J; Dawids, Steen; Hesse, J; Olsen, Niels Vidiendal

    1985-01-01

    In 23 patients with pancreatitis, daily pain for at least 3 months, and no abuse of alcohol, the pain-relieving effect of electroacupuncture (13 patients) or transcutaneous electric nerve stimulation (TENS) (16 patients) was studied. In two prospective studies with a cross-over design, active...

  16. PLASMA EXTRAVASATION IN THE VISCERAL ORGANS CAUSED BY ELECTRICAL STIMULATION OF ACUPOINT “ZUSANLI” IN RATS

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Objective:To investigate the plasma extravasation of visceral organs caused by electrical stimulation of acupoint under the dorsal root reflex and axon reflex conditions.Methods:By the means of measuring the content of Evans blue,this study investigated the plasma extravasation of visceral organs induced by electrical stimulation of acupoint "Zusanli"(ST36).Results:The Evans blue content in the visceral organs such as liver,Spleen,pancreas and the whole gastrointestinal tract in rats increased significantly after electrical stimulation of acupoint"Zusanli" Compared with that of the control group(P<0.01),The evans blue xetravasstion in the above visceral organs was blocked by pre-treatment of capsaicin(66mmol.L-1,50μL)into the acupoint.Conclusion:The neurogenic inflammation of the visceral organs evoked by electrical stimulation of acupoint was mediated by the capsaicin-sensitive afferent fibers through the dorsal root reflex and axon reflex.It is a new method to study the correlation of meridian-viscera.

  17. Effects of preoperative neuromuscular electrical stimulation on quadriceps strength and functional recovery in total knee arthroplasty. A pilot study.

    LENUS (Irish Health Repository)

    Walls, Raymond J

    2010-01-01

    Supervised preoperative muscle strengthening programmes (prehabilitation) can improve recovery after total joint arthroplasty but are considered resource intensive. Neuromuscular electrical stimulation (NMES) has been shown to improve quadriceps femoris muscle (QFM) strength and clinical function in subjects with knee osteoarthritis (OA) however it has not been previously investigated as a prehabilitation modality.

  18. Electrical stimulation of skeletal muscles. An alternative to aerobic exercise training in patients with chronic heart failure?

    Science.gov (United States)

    Dobsák, Petr; Nováková, Marie; Fiser, Bohumil; Siegelová, Jarmila; Balcárková, Pavla; Spinarová, Lenka; Vítovec, Jirí; Minami, Naoyoshi; Nagasaka, Makoto; Kohzuki, Masahiro; Yambe, Tomoyuki; Imachi, Kou; Nitta, Shin-ichi; Eicher, Jean-Christophe; Wolf, Jean-Eric

    2006-05-01

    The aim of this study was to investigate whether electrical stimulation of skeletal muscles could represent a rehabilitation alternative for patients with chronic heart failure (CHF). Thirty patients with CHF and NYHA class II-III were randomly assigned to a rehabilitation program using either electrical stimulation of skeletal muscles or bicycle training. Patients in the first group (n = 15) had 8 weeks of home-based low-frequency electrical stimulation (LFES) applied simultaneously to the quadriceps and calf muscles of both legs (1 h/day for 7 days/week); patients in the second group (n = 15) underwent 8 weeks of 40 minute aerobic exercise (3 times a week). After the 8-week period significant increases in several functional parameters were observed in both groups: maximal VO2 uptake (LFES group: from 17.5 +/- 4.4 mL/kg/min to 18.3 +/- 4.2 mL/kg/min, P bicycle group: from 18.1 +/- 3.9 mL/kg/min to 19.3 +/- 4.1 mL/kg/min, P bicycle group: from 91.2 +/- 13.4 W to 112.9 +/- 10.8 W, P bicycle group: from 425 +/- 118 m to 483 +/- 120 m, P bicycle group: from 510 +/- 90 seconds to 611 +/- 112 seconds, P electrical stimulation. LFES should be considered as a valuable alternative to classical exercise training in patients with CHF. PMID:16823250

  19. Changes of Excitability in M1 Induced by Neuromuscular Electrical Stimulation Differ Between Presence and Absence of Voluntary Drive

    Science.gov (United States)

    Sugawara, Kenichi; Tanabe, Shigeo; Higashi, Toshio; Tsurumi, Takamasa; Kasai, Tatsuya

    2011-01-01

    The aim of this study is to investigate excitability changes in the human motor cortex induced by variable therapeutic electrical stimulations (TESs) with or without voluntary drive. We recorded motor-evoked potentials (MEPs) from extensor and flexor carpi radialis (FCR) muscles at rest and during FCR muscle contraction after the application of…

  20. Effect of three postmortem electrical stimulation treatments on the quality of early-deboned broiler breast meat

    Science.gov (United States)

    Electrical stimulation (ES) of animal carcasses during postmortem has been commonly used by beef industry to enhance meat tenderness, and has been recently adapted for commercial use with poultry. Majority of published investigations of ES effects on the tenderness of early-deboned poultry breast m...

  1. Effects of Electrical Stimulation, Exercise Training and Motor Skills Training on Strength of Children with Meningomyelocele: A Systematic Review

    Science.gov (United States)

    Dagenais, Liese M.; Lahay, Erin R.; Stueck, Kailey A.; White, Erin; Williams, Lindsay; Harris, Susan R.

    2009-01-01

    This systematic review provides a critical synthesis of research regarding the effects of electrical stimulation, exercise training, and motor skills training on muscle strength in children with meningomyelocele. Nine databases were searched using terms related to meningomyelocele and physical therapy interventions. Of 298 potentially relevant…

  2. Effects of electrical stimulation or voluntary contraction for strengthening the quadriceps femoris muscles in an aged male population.

    Science.gov (United States)

    Caggiano, E; Emrey, T; Shirley, S; Craik, R L

    1994-07-01

    Since musculoskeletal impairment increases with age, it is important to determine if exercise changes age-related muscle weakness. This study compared the training effects of electrical stimulation and voluntary isometric contraction, the traditional exercise, on the quadriceps femoris in males 65 years and older. Eighteen informed, nondisabled males, 72 +/- 4 years of age, participated in 12 training sessions over 4 weeks. Maximal voluntary isometric contraction (MVIC) torque was measured with a Cybex II dynamometer prior to and following training. An interclass correlation coefficient (3,1) of 0.982 demonstrated repeated reliable torque measurement. The electrical stimulation group trained at an average of 36% of pretest MVIC; the traditional exercise group trained at an average of 42% MVIC. Average (F = 14.06, p = 0.004) and peak (F = 14.32, p = 0.004) torque values were increased with both modes of training. Both methods of training using a low training load were effective in increasing torque in this older male sample. Electrical stimulation has the same potential as traditional exercise to provide improved strength for aged males. Future research should examine electrical stimulation in older persons with compromised ability to exercise using traditional methods. PMID:8081406

  3. Effects of different frequencies of transcutaneous electrical nerve stimulation on venous vascular reactivity

    Directory of Open Access Journals (Sweden)

    O.S. Franco

    2014-05-01

    Full Text Available Transcutaneous electrical nerve stimulation (TENS is a type of therapy used primarily for analgesia, but also presents changes in the cardiovascular system responses; its effects are dependent upon application parameters. Alterations to the cardiovascular system suggest that TENS may modify venous vascular response. The objective of this study was to evaluate the effects of TENS at different frequencies (10 and 100 Hz on venous vascular reactivity in healthy subjects. Twenty-nine healthy male volunteers were randomized into three groups: placebo (n=10, low-frequency TENS (10 Hz, n=9 and high-frequency TENS (100 Hz, n=10. TENS was applied for 30 min in the nervous plexus trajectory from the superior member (from cervical to dorsal region of the fist at low (10 Hz/200 μs and high frequency (100 Hz/200 μs with its intensity adjusted below the motor threshold and intensified every 5 min, intending to avoid accommodation. Venous vascular reactivity in response to phenylephrine, acetylcholine (endothelium-dependent and sodium nitroprusside (endothelium-independent was assessed by the dorsal hand vein technique. The phenylephrine effective dose to achieve 70% vasoconstriction was reduced 53% (P<0.01 using low-frequency TENS (10 Hz, while in high-frequency stimulation (100 Hz, a 47% increased dose was needed (P<0.01. The endothelium-dependent (acetylcholine and independent (sodium nitroprusside responses were not modified by TENS, which modifies venous responsiveness, and increases the low-frequency sensitivity of α1-adrenergic receptors and shows high-frequency opposite effects. These changes represent an important vascular effect caused by TENS with implications for hemodynamics, inflammation and analgesia.

  4. K+-induced alterations in airway muscle responsiveness to electrical field stimulation

    International Nuclear Information System (INIS)

    We investigated possible pre- and postsynaptic effects of K+-induced depolarization on ferret tracheal smooth muscle (TSM) responsiveness to cholinergic stimulation. To assess electromechanical activity, cell membrane potential (Em) and tension (Tm) were simultaneously recorded in buffer containing 6, 12, 18, or 24 mM K+ before and after electrical field stimulation (EFS) or exogenous acetylcholine (ACh). In 6 mM K+, Em was -58.1 +/- 1.0 mV (mean +/- SE). In 12 mM K+, Em was depolarized to -52.3 +/- 0.9 mV, basal Tm did not change, and both excitatory junctional potentials and contractile responses to EFS at short stimulus duration were larger than in 6 mM K+. No such potentiation occurred at a higher K+, although resting Em and Tm increased progressively above 12 mM K+. The sensitivity of ferret TSM to exogenous ACh appeared unaffected by K+. To determine whether the hyperresponsiveness in 12 mM K+ was due, in part, to augmented ACh release from intramural airway nerves, experiments were done using TSM preparations incubated with [3H]choline to measure [3H]ACh release at rest and during EFS. Although resting [3H]ACh release increased progressively in higher K+, release evoked by EFS was maximal in 12 mM K+ and declined in higher concentrations. We conclude that small elevations in the extracellular K+ concentration augment responsiveness of the airways, by increasing the release of ACh both at rest and during EFS from intramural cholinergic nerve terminals. Larger increases in K+ appear to be inhibitory, possibly due to voltage-dependent effects that occur both pre- and postsynaptically

  5. K+-induced alterations in airway muscle responsiveness to electrical field stimulation

    International Nuclear Information System (INIS)

    The authors investigated possible pre- and postsynaptic effects of K+-induced depolarization on ferret tracheal smooth muscle (TSM) responsiveness to cholinergic stimulation. To assess electromechanical activity, cell membrane potential (E/sub m/) and tension (T/sub m/) were simultaneously recorded in buffer containing 6, 12, 18, or 24 mM K+ before and after electrical field stimulation (EFS) or exogenous acetylcholine (ACh). In 6 mM K+ E/sub m/ was -58.1 +/- 1.0 m V (mean +/- SE). In 12 mM K+, E/sub m/ was depolarized to -52.3 +/- 0.9 mV, basal T/sub m/ did not change, and both excitatory junctional potentials and contractile responses to EFS at short stimulus duration were larger than in 6 mM K+. No such potentiation occurred at a higher K+, although resting E/sub m/ and T/sub m/ increased progressively above 12 mM K+. The sensitivity of ferret TSM to exogenous ACh appeared unaffected by K+. To determine whether the hyperresponsiveness in 12 mM K+ was due, in part, to augmented ACh release from intramural airway nerves, experiments were done using TSM preparations incubated with [3H]choline to measure [3H]ACh release at rest and during EFS. Although resting [3H]ACh release increased progressively in higher K+, release evoked by EFS was maximal in 12 mM K+ and declined in higher concentrations. They conclude that small elevations in the extracellular K+ concentration augment responsiveness of the airways, by increasing the release of ACh both at rest and during EFS from intramural cholinergic nerve terminals. Larger increases in K+ appear to be inhibitory, possibly due to voltage-dependent effects that occur both pre- and postsynaptically

  6. Effects of different frequencies of transcutaneous electrical nerve stimulation on venous vascular reactivity

    Energy Technology Data Exchange (ETDEWEB)

    Franco, O.S.; Paulitsch, F.S.; Pereira, A.P.C.; Teixeira, A.O. [Universidade Federal do Rio Grande, Faculdade de Medicina, Programa de Pós-Graduação em Ciências da Saúde, Rio Grande, RS, Brasil, Programa de Pós-Graduação em Ciências da Saúde, Faculdade de Medicina, Universidade Federal do Rio Grande, Rio Grande, RS (Brazil); Martins, C.N. [Universidade Federal do Rio Grande, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Fisiologia Animal Comparada, Rio Grande, RS, Brasil, Programa de Pós-Graduação em Fisiologia Animal Comparada, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Rio Grande, RS (Brazil); Silva, A.M.V. [Universidade Federal de Santa Maria, Departamento de Fisioterapia e Reabilitação, Santa Maria, RS, Brasil, Departamento de Fisioterapia e Reabilitação, Universidade Federal de Santa Maria, Santa Maria, RS (Brazil); Plentz, R.D.M. [Universidade Federal de Ciências da Saúde de Porto Alegre, Programa de Pós-Graduação em Ciências da Reabilitação, Programa de Pós-Graduação em Ciências da Saúde, Porto Alegre, RS, Brasil, Programa de Pós-Graduação em Ciências da Saúde, Programa de Pós-Graduação em Ciências da Reabilitação, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, RS (Brazil); Irigoyen, M.C. [Faculdade de Medicina, Universidade de São Paulo, Instituto do Coração, Unidade de Hipertensão, São Paulo, SP, Brasil, Unidade de Hipertensão, Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Signori, L.U. [Universidade Federal do Rio Grande, Faculdade de Medicina, Programa de Pós-Graduação em Ciências da Saúde, Rio Grande, RS, Brasil, Programa de Pós-Graduação em Ciências da Saúde, Faculdade de Medicina, Universidade Federal do Rio Grande, Rio Grande, RS (Brazil); Universidade Federal do Rio Grande, Instituto de Ciências Biológicas, Programa de Pós-Graduação em Fisiologia Animal Comparada, Rio Grande, RS, Brasil, Programa de Pós-Graduação em Fisiologia Animal Comparada, Instituto de Ciências Biológicas, Universidade Federal do Rio Grande, Rio Grande, RS (Brazil); Universidade Federal de Santa Maria, Departamento de Fisioterapia e Reabilitação, Santa Maria, RS, Brasil, Departamento de Fisioterapia e Reabilitação, Universidade Federal de Santa Maria, Santa Maria, RS (Brazil)

    2014-04-04

    Transcutaneous electrical nerve stimulation (TENS) is a type of therapy used primarily for analgesia, but also presents changes in the cardiovascular system responses; its effects are dependent upon application parameters. Alterations to the cardiovascular system suggest that TENS may modify venous vascular response. The objective of this study was to evaluate the effects of TENS at different frequencies (10 and 100 Hz) on venous vascular reactivity in healthy subjects. Twenty-nine healthy male volunteers were randomized into three groups: placebo (n=10), low-frequency TENS (10 Hz, n=9) and high-frequency TENS (100 Hz, n=10). TENS was applied for 30 min in the nervous plexus trajectory from the superior member (from cervical to dorsal region of the fist) at low (10 Hz/200 μs) and high frequency (100 Hz/200 μs) with its intensity adjusted below the motor threshold and intensified every 5 min, intending to avoid accommodation. Venous vascular reactivity in response to phenylephrine, acetylcholine (endothelium-dependent) and sodium nitroprusside (endothelium-independent) was assessed by the dorsal hand vein technique. The phenylephrine effective dose to achieve 70% vasoconstriction was reduced 53% (P<0.01) using low-frequency TENS (10 Hz), while in high-frequency stimulation (100 Hz), a 47% increased dose was needed (P<0.01). The endothelium-dependent (acetylcholine) and independent (sodium nitroprusside) responses were not modified by TENS, which modifies venous responsiveness, and increases the low-frequency sensitivity of α1-adrenergic receptors and shows high-frequency opposite effects. These changes represent an important vascular effect caused by TENS with implications for hemodynamics, inflammation and analgesia.

  7. Effects of different frequencies of transcutaneous electrical nerve stimulation on venous vascular reactivity

    International Nuclear Information System (INIS)

    Transcutaneous electrical nerve stimulation (TENS) is a type of therapy used primarily for analgesia, but also presents changes in the cardiovascular system responses; its effects are dependent upon application parameters. Alterations to the cardiovascular system suggest that TENS may modify venous vascular response. The objective of this study was to evaluate the effects of TENS at different frequencies (10 and 100 Hz) on venous vascular reactivity in healthy subjects. Twenty-nine healthy male volunteers were randomized into three groups: placebo (n=10), low-frequency TENS (10 Hz, n=9) and high-frequency TENS (100 Hz, n=10). TENS was applied for 30 min in the nervous plexus trajectory from the superior member (from cervical to dorsal region of the fist) at low (10 Hz/200 μs) and high frequency (100 Hz/200 μs) with its intensity adjusted below the motor threshold and intensified every 5 min, intending to avoid accommodation. Venous vascular reactivity in response to phenylephrine, acetylcholine (endothelium-dependent) and sodium nitroprusside (endothelium-independent) was assessed by the dorsal hand vein technique. The phenylephrine effective dose to achieve 70% vasoconstriction was reduced 53% (P<0.01) using low-frequency TENS (10 Hz), while in high-frequency stimulation (100 Hz), a 47% increased dose was needed (P<0.01). The endothelium-dependent (acetylcholine) and independent (sodium nitroprusside) responses were not modified by TENS, which modifies venous responsiveness, and increases the low-frequency sensitivity of α1-adrenergic receptors and shows high-frequency opposite effects. These changes represent an important vascular effect caused by TENS with implications for hemodynamics, inflammation and analgesia

  8. Cytoprotective Role of Nrf2 in Electrical Pulse Stimulated C2C12 Myotube.

    Directory of Open Access Journals (Sweden)

    Masaki Horie

    Full Text Available Regular physical exercise is central to a healthy lifestyle. However, exercise-related muscle contraction can induce reactive oxygen species and reactive nitrogen species (ROS/RNS production in skeletal muscle. The nuclear factor-E2-related factor-2 (Nrf2 transcription factor is a cellular sensor for oxidative stress. Regulation of nuclear Nrf2 signaling regulates antioxidant responses and protects organ structure and function. However, the role of Nrf2 in exercise- or contraction-induced ROS/RNS production in skeletal muscle is not clear. In this study, using differentiated C2C12 cells and electrical pulse stimulation (EPS of muscle contraction, we explored whether Nrf2 plays a role in the skeletal muscle response to muscle contraction-induced ROS/RNS. We found that EPS (40 V, 1 Hz, 2 ms stimulated ROS/RNS accumulation and Nrf2 activation. We also showed that expression of NQO1, HO-1 and GCLM increased after EPS-induced muscle contraction and was remarkably suppressed in cells with Nrf2 knockdown. We also found that the antioxidant N-acetylcysteine (NAC significantly attenuated Nrf2 activation after EPS, whereas the nitric oxide synthetase inhibitor Nω-nitro-L-arginine methyl ester (L-NAME did not. Furthermore, Nrf2 knockdown after EPS markedly decreased ROS/RNS redox potential and cell viability and increased expression of the apoptosis marker Annexin V in C2C12 myotubes. These results indicate that Nrf2 activation and expression of Nrf2 regulated-genes protected muscle against the increased ROS caused by EPS-induced muscle contraction. Thus, our findings suggest that Nrf2 may be a key factor for preservation of muscle function during muscle contraction.

  9. Comparison of 2 methods of non-invasive treatment between transcutaneous electrical stimulation and pulsed electromagnetic field stimulation as replacement of invasive manual acupuncture.

    Science.gov (United States)

    Kim, Soo-Byeong; Kim, Jung-Yoon; Park, Sun-Woo; Lee, Na-Ra; Lee, Seung-Wook; Kim, Young-Ho; Lee, Yong-Heum

    2012-01-01

    The aim of this study was to find the non-invasive optimal alternative method for Manual Acupuncture. Existing researches had reported that Transcutaneous Electrical Acupoint Stimulation (TEAS) was an effective treatment method instead of manual acupuncture. In place of the TEAS, we suggested the Pulsed Electromagnetic Fields (PEMFs). Thus, we designed the PEMFs system which can stimulate only an acupoint. There have been no researches which reported therapeutic effect when stimulating at an identical acupoint by TEAS and PEMFs. Hence, this study investigated the therapeutic effect on the muscle fatigue after the strenuous knee extension/flexion exercise by two stimulations. We selected the stimulation method of both TEAS and PEMFs by using 2Hz biphasic rectangular wave pulse and pulse width 0.2ms. The magnetic flux was the 30.92mT (309.2gauss) at 2 Hz. The electromyogram (EMG) and the maximal voluntary contraction (MVC) at rectus femoris were measured. The Median Frequency (MF) at TEAS group was significantly effective at 6 minutes (p=0.499). The PEMFs group was recovered to the MF rapidly after 4 minutes (p=0.166). The results of the peak torque indicated that both non-stimulation group and TEAS group did not recover to the peak torque at pre-exercise during the recovery period (p<0.05). In contrast, the significant treatment effect of PEMFs group was found after 14 minutes (p=0.135). The results of this study demonstrated that PEMFs were better than TEAS as a non-invasive method to replace the manual acupuncture. PMID:23409610

  10. Tinnitus Suppression by Intracochlear Electrical Stimulation in Single Sided Deafness – A Prospective Clinical Trial: Follow-Up

    Science.gov (United States)

    Arts, Remo A. G. J.; George, Erwin L. J.; Janssen, Miranda; Griessner, Andreas; Zierhofer, Clemens; Stokroos, Robert J.

    2016-01-01

    Introduction Earlier studies show that a Cochlear Implant (CI), capable of providing intracochlear electrical stimulation independent of environmental sounds, appears to suppress tinnitus at least for minutes. The current main objective is to compare the long-term suppressive effects of looped (i.e. repeated) electrical stimulation (without environmental sound perception) with the standard stimulation pattern of a CI (with environmental sound perception). This could open new possibilities for the development of a “Tinnitus Implant” (TI), an intracochlear pulse generator for the suppression of tinnitus. Materials and Methods Ten patients with single sided deafness suffering from unilateral tinnitus in the deaf ear are fitted with a CI (MED-EL Corporation, Innsbruck, Austria). Stimulation patterns are optimized for each individual patient, after which they are compared using a randomized crossover design, with a follow-up of six months, followed by a 3 month period using the modality of patient’s choice. Results Results show that tinnitus can be suppressed with intracochlear electrical stimulation independent of environmental sounds, even long term. No significant difference in tinnitus suppression was found between the standard clinical CI and the TI. Conclusion It can be concluded that coding of environmental sounds is no requirement for tinnitus suppression with intracochlear electrical stimulation. It is therefore plausible that tinnitus suppression by CI is not solely caused by an attention shift from the tinnitus to environmental sounds. Both the standard clinical CI and the experimental TI are potential treatment options for tinnitus. These findings offer perspectives for a successful clinical application of the TI, possibly even in patients with significant residual hearing. Trial Registration TrialRegister.nl NTR3374 PMID:27111333

  11. Schottky barrier breakdown in Si stimulation by exciton drift in inhomogeneous electric field at 4.2 K

    International Nuclear Information System (INIS)

    Experimental study of the mechanism of the Schottky barrier breakdown stimulation in photoexcited silicon in the strong electric field at 4.2 K is presented. The effect of photoexcitation intensity and the intensity of the electric field applied, as well as the influence of their time on breakdown mechanism were studied. It is shown that Schottky barrier breakdown occurs due to the narrowing of the spatial charged region caused by the exciton drift under the inhomogeneous electric field and electron recombination at the barrier ionized impurity levels

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

    OpenAIRE

    Mattar, J.; Turk, M.; 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. Th...

  13. Acupressure and Transcutaneous Electrical Acupoint Stimulation for Improving Uremic Pruritus: A Randomized, Controlled Trial.

    Science.gov (United States)

    Kılıç Akça, Nazan; Taşcı, Sultan

    2016-03-01

    Context • Uremic pruritus, a frequent and compromising symptom for patients with advanced or end-stage renal disease (ESRD), strongly reduces the patient's quality of life. Pruritus may be extremely difficult to control because therapeutic options are limited. Topical products are frequently used for easing pruritus, but their effects are generally temporary and marginal. Although acupressure and electrical-stimulation methods for the application of acupressure have been evaluated separately in terms of pruritus efficiency in different studies, the existence of any difference between the efficacies of the 2 methods has not been assessed yet. Objective • The study intended to test the effectiveness of acupressure and transcutaneous electrical acupoint stimulation (TEAS) on uremic pruritus in patients who were receiving the routine hemodialysis treatment. Design • The study was a randomized, controlled trial. Setting • The study took place in hemodialysis units located in hemodialysis centers in Turkey. Participants • Participants were patients in the hemodialysis units who were under hemodialysis treatment and had experienced uremic pruritus. Intervention • Participants were randomly assigned to the acupressure group (intervention group), the TEAS group (intervention group), or the control group. For the 2 intervention groups, the treatment was applied 3 ×/wk during the 4 wk of the study on the large intestine (LI-11) acupuncture points in the arm, for a total of 12 sessions. Outcome Measures • The study measured the severity of participants' pruritus using a patient information form and a visual analogue scale (VAS). The data were collected at baseline and posttreatment. Results • A total of 75 patients participated in the study. The results indicated that patients in the acupressure and TEAS groups had significant reductions from baseline to posttreatment in their levels of discomfort from uremic pruritus compared with patients in the control

  14. Electrical stimulation of the aortic depressor nerve in conscious rats overcomes the attenuation of the baroreflex in chronic heart failure.

    Science.gov (United States)

    Pinto, Tomás O C Teixeira; Lataro, Renata M; Castania, Jaci A; Durand, Marina T; Silva, Carlos A A; Patel, Kaushik P; Fazan, Rubens; Salgado, Helio C

    2016-04-01

    Chronic heart failure (CHF) is characterized by autonomic dysfunction combined with baroreflex attenuation. The hypotensive and bradycardic responses produced by electrical stimulation of the aortic depressor nerve (ADN) were examined in conscious CHF and control male Wistar rats (12-13 wk old). Furthermore, the role of parasympathetic and sympathetic nervous system in mediating the cardiovascular responses to baroreflex activation was evaluated by selective β1-adrenergic and muscarinic receptor antagonists. CHF was induced by myocardial infarction. After 6 wk, the subjects were implanted with electrodes for ADN stimulation. Twenty-four hours later, electrical stimulation of the ADN was applied for 20 s using five different frequencies (5, 15, 30, 60, and 90 Hz), while the arterial pressure was recorded by a catheter implanted into the femoral artery. Electrical stimulation of the ADN elicited progressive and similar hypotensive and bradycardic responses in control (n= 12) and CHF (n= 11) rats, while the hypotensive response was not affected by methylatropine. Nevertheless, the reflex bradycardia was attenuated by methylatropine in control, but not in CHF rats. Atenolol did not affect the hypotensive or bradycardic response in either group. The ADN function was examined under anesthesia through electroneurographic recordings. The arterial pressure-ADN activity relationship was attenuated in CHF rats. In conclusion, despite the attenuation of baroreceptor function in CHF rats, the electrical stimulation of the ADN elicited a stimulus-dependent hypotension and bradycardia of similar magnitude as observed in control rats. Therefore, electrical activation of the aortic baroreflex overcomes both the attenuation of parasympathetic function and the sympathetic overdrive. PMID:26843582

  15. Retinal ganglion cells: mechanisms underlying depolarization block and differential responses to high frequency electrical stimulation of ON and OFF cells

    Science.gov (United States)

    Kameneva, T.; Maturana, M. I.; Hadjinicolaou, A. E.; Cloherty, S. L.; Ibbotson, M. R.; Grayden, D. B.; Burkitt, A. N.; Meffin, H.

    2016-02-01

    Objective. ON and OFF retinal ganglion cells (RGCs) are known to have non-monotonic responses to increasing amplitudes of high frequency (2 kHz) biphasic electrical stimulation. That is, an increase in stimulation amplitude causes an increase in the cell’s spike rate up to a peak value above which further increases in stimulation amplitude cause the cell to decrease its activity. The peak response for ON and OFF cells occurs at different stimulation amplitudes, which allows differential stimulation of these functional cell types. In this study, we investigate the mechanisms underlying the non-monotonic responses of ON and OFF brisk-transient RGCs and the mechanisms underlying their differential responses. Approach. Using in vitro patch-clamp recordings from rat RGCs, together with simulations of single and multiple compartment Hodgkin-Huxley models, we show that the non-monotonic response to increasing amplitudes of stimulation is due to depolarization block, a change in the membrane potential that prevents the cell from generating action potentials. Main results. We show that the onset for depolarization block depends on the amplitude and frequency of stimulation and reveal the biophysical mechanisms that lead to depolarization block during high frequency stimulation. Our results indicate that differences in transmembrane potassium conductance lead to shifts of the stimulus currents that generate peak spike rates, suggesting that the differential responses of ON and OFF cells may be due to differences in the expression of this current type. We also show that the length of the axon’s high sodium channel band (SOCB) affects non-monotonic responses and the stimulation amplitude that leads to the peak spike rate, suggesting that the length of the SOCB is shorter in ON cells. Significance. This may have important implications for stimulation strategies in visual prostheses.

  16. Non-linear analysis of body responses to functional electrical stimulation on hemiplegic subjects.

    Science.gov (United States)

    Yu, W W; Acharya, U R; Lim, T C; Low, H W

    2009-08-01

    Functional electrical stimulation (FES) is a method of applying low-level electrical currents to restore or improve body functions lost through nervous system impairment. FES is applied to peripheral nerves that control specific muscles or muscle groups. Application of advanced signal computing techniques to the medical field has helped to achieve practical solutions to the health care problems accurately. The physiological signals are essentially non-stationary and may contain indicators of current disease, or even warnings about impending diseases. These indicators may be present at all times or may occur at random on the timescale. However, to study and pinpoint these subtle changes in the voluminous data collected over several hours is tedious. These signals, e.g. walking-related accelerometer signals, are not simply linear and involve non-linear contributions. Hence, non-linear signal-processing methods may be useful to extract the hidden complexities of the signal and to aid physicians in their diagnosis. In this work, a young female subject with major neuromuscular dysfunction of the left lower limb, which resulted in an asymmetric hemiplegic gait, participated in a series of FES-assisted walking experiments. Two three-axis accelerometers were attached to her left and right ankles and their corresponding signals were recorded during FES-assisted walking. The accelerometer signals were studied in three directions using the Hurst exponent H, the fractal dimension (FD), the phase space plot, and recurrence plots (RPs). The results showed that the H and FD values increase with increasing FES, indicating more synchronized variability due to FES for the left leg (paralysed leg). However, the variation in the normal right leg is more chaotic on FES. PMID:19743632

  17. Glucose metabolic change after visual and electrical stimulation of the rabbit retina using [18F]FDG PET: a preliminary result

    International Nuclear Information System (INIS)

    We studied to compare the cerebral cortical metabolic change after visual and electrical stimulation of the rabbit retina. Five PET scans were performed on five different days in an albino rabbit. One FDG PET study was done at rest state. In another two FDG PET studies, repetitive flash light stimulation (0.3 Hz, 6 min total) on each eye started 1 min prior to FDG injection and continued for 5 min into uptake. In the other two FDG studies, electrical retinal stimulation (500 μA, 1 Hz, 6 min total) of each eye using a suprachoroidal electrode placed under the visual streak was performed with the same procedure. Static PET data was acquired for 10 min after injection of [18F]FDG (37 MBq) through the catheter placed in the ear vein. All images were realigned to the rest state image. To remove the effects of global differences, each voxel value of the images was normalized versus mean value in whole brain. Change of cerebral glucose metabolism was examined with difference between rest and stimulation state. After visual and electrical stimulation of the rabbit retina, the cerebral area of increased metabolism could be determined. The hypermetabolic area of electrical stimulation overlapped with the area of visual stimulation, while electrically simulated cerebral area was focal and confined within the visually activated area. The electrical stimulation of the rabbit retina could increase the metabolism of the visual cortex which indicates electrical retinal stimulation caused visual perception of brain

  18. Glucose metabolic change after visual and electrical stimulation of the rabbit retina using [{sup 18}F]FDG PET: a preliminary result

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Su Jin; Lee, Jae Sung; Woo, Se Joon; Seo, Jong Mo; Chung, Hum; Lee, Dong Soo; Zhou, Zing Ai; Kim, Sung June [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

    2007-07-01

    We studied to compare the cerebral cortical metabolic change after visual and electrical stimulation of the rabbit retina. Five PET scans were performed on five different days in an albino rabbit. One FDG PET study was done at rest state. In another two FDG PET studies, repetitive flash light stimulation (0.3 Hz, 6 min total) on each eye started 1 min prior to FDG injection and continued for 5 min into uptake. In the other two FDG studies, electrical retinal stimulation (500 {mu}A, 1 Hz, 6 min total) of each eye using a suprachoroidal electrode placed under the visual streak was performed with the same procedure. Static PET data was acquired for 10 min after injection of [{sup 18}F]FDG (37 MBq) through the catheter placed in the ear vein. All images were realigned to the rest state image. To remove the effects of global differences, each voxel value of the images was normalized versus mean value in whole brain. Change of cerebral glucose metabolism was examined with difference between rest and stimulation state. After visual and electrical stimulation of the rabbit retina, the cerebral area of increased metabolism could be determined. The hypermetabolic area of electrical stimulation overlapped with the area of visual stimulation, while electrically simulated cerebral area was focal and confined within the visually activated area. The electrical stimulation of the rabbit retina could increase the metabolism of the visual cortex which indicates electrical retinal stimulation caused visual perception of brain.

  19. Electromagnetic Field Modeling of Transcranial Electric and Magnetic Stimulation: Targeting, Individualization, and Safety of Convulsive and Subconvulsive Applications

    Science.gov (United States)

    Deng, Zhi-De

    The proliferation of noninvasive transcranial electric and magnetic brain stimulation techniques and applications in recent years has led to important insights into brain function and pathophysiology of brain-based disorders. Transcranial electric and magnetic stimulation encompasses a wide spectrum of methods that have developed into therapeutic interventions for a variety of neurological and psychiatric disorders. Although these methods are at different stages of development, the physical principle underlying these techniques is the similar. Namely, an electromagnetic field is induced in the brain either via current injection through scalp electrodes or via electromagnetic induction. The induced electric field modulates the neuronal transmembrane potentials and, thereby, neuronal excitability or activity. Therefore, knowledge of the induced electric field distribution is key in the design and interpretation of basic research and clinical studies. This work aims to delineate the fundamental physical limitations, tradeoffs, and technological feasibility constraints associated with transcranial electric and magnetic stimulation, in order to inform the development of technologies that deliver safer, and more spatially, temporally, and patient specific stimulation. Part I of this dissertation expounds on the issue of spatial targeting of the electric field. Contrasting electroconvulsive therapy (ECT) and magnetic seizure therapy (MST) configurations that differ markedly in efficacy, side effects, and seizure induction efficiency could advance our understanding of the principles linking treatment parameters and therapeutic outcome and could provide a means of testing hypotheses of the mechanisms of therapeutic action. Using the finite element method, we systematically compare the electric field characteristics of existing forms of ECT and MST. We introduce a method of incorporating a modality-specific neural activation threshold in the electric field models that can

  20. Comparison of functional electrical stimulation associated with kinesiotherapy and kinesiotherapy alone in patients with hemiparesis during the subacute phase of ischemic cerebrovascular accident

    OpenAIRE

    Paulo Cesar Modesto; Fernando Campos Gomes Pinto

    2013-01-01

    Objective: To compare the functional electrical stimulation associated with functional kinesiotherapy alone in patients after ischemic cerebrovascular accident. Methods: The study included 20 patients who were divided into two groups: Group I (GI): functional electrical stimulation plus functional kinesiotherapy and Group II (GII): functional kinesiotherapy. We evaluated active and passive range of motion, in knee flexion and extension muscle strength, activities of daily ...