The shortest duration of an electrical stimulus where the threshold amplitude is twice the rheobase - the minimum required for eliciting an ACTION POTENTIAL at any time period. It is a measure of the excitability of nerve or muscle tissue, and is characteristic of types and/or condition of the nerve or muscle cells in the tissue.

Strength-duration relationship for intra- versus extracellular stimulation with microelectrodes. (1/4)

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Effect of pacing rate on the human atrial strength-duration curve. (2/4)

The effect of rapid pacing on the atrial constant voltage stimulation threshold in humans has not been defined at rates applicable to those of antitachycardia pacing. The effect of pacing rate on the atrial strength-duration relation was determined in 10 patients at pacing rates between 125 and 300 beats/min to explore excitability over the range of rates used for permanent antitachycardia pacing systems. Two points that define the strength-duration curve were measured at each pacing rate: rheobase voltage--the lowest stimulus voltage that results in capture at a pulse duration of 2 ms; and chronaxie pulse duration--the threshold pulse duration at twice rheobase voltage. A permanent, tined, J-shaped pacing lead with a high current density and low polarization electrode was positioned in the right atrial appendage for cathodal stimulation. A constant voltage output, incorporating a fast recharge pulse designed to minimize electrode polarization, was used for stimulation. There was a significant increase in rheobase voltage (p = 0.009), chronaxie pulse duration (p = 0.001) and minimal threshold stimulus energy (p = 0.05) at pacing rates greater than 225 beats/min. A rheobase voltage greater than 5 V occurred in three patients at pacing rates greater than or equal to 275 beats/min. At a pacing rate of 300 beats/min, rheobase voltage had increased in 8 of 10 patients.(ABSTRACT TRUNCATED AT 250 WORDS)  (+info)

Biophysical properties of the longitudinal smooth muscle of the guinea-pig rectum. (3/4)

1. The membrane properties of the longitudinal muscle layer of the guinea-pig rectum were studied in hypertonic solution (twice the normal Krebs by addition of sucrose) by the micro-electrode technique. To produce the electrotonic potential and spike, stimulating partitions were used.2. Hypertonic solution hyperpolarized the membrane and increased the membrane resistance. However, no change in the space constant was observed before and after treatment with hypertonic solution.3. The appearance and amplitude of the spike became regular after treatment with hypertonic solution and appearance of the overshoot was consistent.4. The characteristic constants and the conduction velocity were measured in hypertonic solution.(i) The space constant of the membrane was 0.81 mm, the time constant of the electrotonic potential was 83.7 msec and the time constant of the foot of the propagated spike was 8.8 msec.(ii) The conduction velocity of the excitation measured by insertions of the two micro-electrodes was 4.4 cm/sec.(iii) The chronaxie of the membrane was 71.3 msec.5. The results obtained from the present experiments were discussed in relation to the cable theory, and it was concluded that the passive properties of the membrane of the rectal smooth muscle could be explained by the cable equations.6. The specificities of the electrical properties of rectal smooth muscle were compared with muscle from other regions of the alimentary canal.  (+info)

Properties of two unmyelinated fibre tracts of the central nervous system: lateral Lissauer tract, and parallel fibres of the cerebellum. (4/4)

1. Monoplar tungsten micro-electrodes were used to stimulate and platinun plated tungsten micro-electrodes to record from single, unmyelinated cerebellar parallel fibres and lateral Lissauer tract axons in cats. 2. Stimulation of the lateral Lissauer tract resulted in the activation of a narrow, longitudinal 'beam', much as on the cerebellar surface. 3. Following impulse conduction, parallel and Lissauer tract fibres showed a supernormal conduction velocity (up to 25% increase) and increased excitability (up to 40% increase). No subnormality was encountered following supernormality. Some Lissauer tract fibres had prolonged relative refractory periods and no supernormal periods. 4. Chronaxies ranged from 155 to 380 microseconds. 5. Single fibres exhibited a remarkable increase in conduction velocity (up to 18% and excitability (up to 40%) following a single subthreshold stimulus. The duration of this effect (up to 20 msec) was much longer than expected from membrane time constant estimates.  (+info)

Looking for Chronaxie? Find out information about Chronaxie. The time interval required to excite a tissue by an electric current of twice the galvanic threshold. McGraw-Hill Dictionary of Scientific & Technical... Explanation of Chronaxie
KRUEGER-BECK, Eddy et al. Action potential: from excitation to neural adaptation. Fisioter. mov. (Impr.) [online]. 2011, vol.24, n.3, pp.535-547. ISSN 1980-5918. http://dx.doi.org/10.1590/S0103-51502011000300018.. INTRODUCTION: The action potential (AP) arises due to a disturbance of the resting state of the cell membrane with consequent flow of ions across the membrane and ion concentration changes in intra and extra cellular space. OBJECTIVES: This article aims to summarize the scientific knowledge accumulated to date on the action potential and neural adaptation in the process of applying a constant stimulus. MATERIALS AND METHODS: This is a literature review on the bases Springer, ScienceDirect, PubMed, IEEE Xplore, Google Scholar, Capes Periodicals Portal as well as books on the topic. The selected preferred language was English with the keywords: action potential; adaptation, accommodation; rheobase; chronaxy; nerve impulse. We conducted a search of articles with a wide time window from ...
Lintasan Traktus Medula Spinalis Jaras Asendens salah satunya berupa jaras nyeri dan suhu Terdapat 3 serabut jaras nyeri dan suhu: Serabut ordo I: membentuk traktus dorsolateralis (Lissauer) Serabut ordo II: membentuk trjatus spinothalamikus lateralis Serabut ordo III: membentuk tractus thalamokortikalis Serabut saraf sensorik masuk ke radiks dorsalis medulla spinalis (membentuk traktus dorsolateralis). Sampai di susbtansia…
1. Strength-duration data for the giant fiber of the great stellar nerve of the squid (Loligo pealii) can be approximately described by several mathematical formulations.. 2. Excitation time constants for isolated giant fibers are essentially the same as constants of the giant fibers in the intact nerve.. 3. The strength-duration curves of the fibers in the intact nerve lie higher on the voltage axis than those of the isolated fibers. It is concluded that the principal effect of other fibers upon the excitation of one fiber in a nerve trunk is that of shunting the stimulating current.. 4. Deterioration of the nerve shifts the curve upward and to the left, resulting in shorter time constants.. 5. Decreasing interelectrode distance also shifts the curve upward and to the left.. 6. Excitation time constants of the giant fibers are larger with plate electrodes than with wire or pore electrodes.. 7. The strength-duration curves of the smaller fin nerve fibers lie consistently to the right of, and the ...
We develop a viscosity solution theory for a system of nonlinear degenerate parabolic integro-partial differential equations (IPDEs) related to stochastic optimal switching and control problems or stochastic games. In the case of stochastic optimal switching and control, we prove via dynamic programming methods that the value function is a viscosity solution of the IPDEs. In our setting the value functions or the solutions of the IPDEs are not smooth, so classical verification theorems do not apply ...
Sensory strength-duration curves were obtained using percutaneous true square-wave pulses ranging from 0.1 to 20.0 ms produced by an isolated constant current stimulator. In 119 healthy volunteers sensory thresholds were measured bilaterally by stimulating the distal phalange of the little finger. In order to examine the relationship of sensory threshold and handedness the latter was assessed by means of the Edinburgh Inventory. An asymmetry of sensory threshold was found for all the subjects and this was more pronounced with shorter stimuli. Of right-handers tested 73.5% had a lower threshold on the left side while 70.8% of left-handers had a lower threshold on the right side. Although threshold asymmetry is associated with handedness this is not necessarily due to cerebral lateralization.. ...
Two more problems remain. One is that rigc.ses and rigxc.ses set up range variable plots over paths that dont exist in the new model cell--they refer to sections with the base name dend, but the new model cell has sections whose base name is dend2 (even if the base names were identical, the shape of the new cell is completely different so the paths that are good for it would probably be quite uninteresting in the new cell). The symptom is that, when the hoc parser reaches a statement that refers to a nonexistent section, NEURON emits an error message about a nonexistent section (finally a helpful error message!) and halts. The quickest fix is to edit these two ses files, identifying the code blocks that set up the windows whose graphs refer to nonexistent sections, comment them out, execute initxstim.hoc again, use the NEURON Main Menu toolbar to bring up a new shape plot, use that shape plot to set up the range variable plots that are of interest, and save new session files. This is a little ...
It is known that lesions of the substantia gelatinosa and Lissauer Tract (LT) are associated with the occurrence of pain in cases of BPA [38]. The posterior horn of the spinal cord (PHSC) and LT are the first integration centers of the primary sensory afferents in the neuroaxis [34]. The LT is located at the apex of PHSC and its fibers are distributed longitudinally along the spinal cord [35]. About one third of its fibers are primary afferents projecting, rostral or caudally for one or more spinal segments [36]. The other fibers originate in the PHSC itself [37,39,40]. Both the medial and lateral sides of the LT contain propriospinal fibers, but only the medial component is associated with nociceptive transmission [41].. It seems that both the medial and lateral components of the LT play an important role in modulating a normal overlapping of receptive fields from different dorsal roots. As the lateral LT plays an inhibitory effect, its lesion leads to a net facilitation of the local neurons ...
I am trying to develop a simple axon model that represents nodes of Ranvier connected by perfectly insulating myelinated internodal segments. Sweeney channel mechanics are used at the nodes (sodium and leakage currents). I would like to apply stimulation to this model using the extracellular mechanism, with the extracellular potentials at the nodes of Ranvier calculated through interpolation within a FEM program (ANSYS Ansoft). Since the internodal myelinated segments are perfectly insulating, I did not add any channel mechanics or transmembrane capacitance to these segments, nor did I apply a non-zero extracellular voltage. My procedure code for creating such an axon is below ...
Lissauer ME, Diaz JJ, Scalea TM, Chiu WC, Weltz AS, Koo G, McCrone MP, Harris DG. Epidemiology and outcomes of acute kidney injury in critically ill surgical patients. Journal of critical care.. 2015 Feb 0; 30(1):102-6. Epub 2014 Aug 06. ...
Mou, Z., Triantis, I., Woods, V. M., Toumazou, C. and Nikolic, K. (2012). A simulation study of the combined thermoelectric extracellular stimulation of the sciatic nerve of the Xenopus laevis: the localized transient heat block. IEEE Transactions on Biomedical Engineering, 59(6), pp. 1758-1769. doi: 10.1109/TBME.2012.2194146 ...
This archive instantiates the single-cell cortical models used in (Aberra et al. 2018) and sets up extracellular stimulation with either a point-current source, to simulate intracortical microstimulation (ICMS), or a uniform E-field distribution, with a monophasic, rectangular pulse waveform in both cases ...
This archive instantiates the single-cell cortical models used in (Aberra et al. 2018) and sets up extracellular stimulation with either a point-current source, to simulate intracortical microstimulation (ICMS), or a uniform E-field distribution, with a monophasic, rectangular pulse waveform in both cases ...
Akesson, T., Albrow, M. G., Almehed, S., Anassontzis, E., Batley, R., Benary, O., Boggild, H., Botner, O., Breuker, H., Burkert, V., Di Ciaccio, A., Cockerill, D., Dagan, S., Dahl-Jensen, E., Dahl-Jensen, I., Damgaard, G., Evans, W. M., Fabjan, C. W., Gordon, H., Hallgren, A., Heck, B., Hilke, H. J., Jarlskog, G., Jeffreys, P., Killian, T., Kourkoumelis, C., Lans, J. V. D., Lissauer, D., Lörstad, B., Ludlam, T., McCubbin, N. A., Mannelli, I., Mjörnmark, U., Molzon, W., Nielsen, Børge Svane, Oren, Y., Palmer, R. B., Rahm, D. C., Rehak, P., Resvanis, L. K., Rosselet, L., Rosso, E., Rudge, A., Schindler, R. H., Schistad, B., Stumer, I., Willis, W. J., Winik, M., Witzeling, W. & Woody, C., 1 aug. 1986, I : Physica Scripta. 34, 2, s. 106-110 5 s.. Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › fagfællebedømt ...
Akesson, T., Albrow, M. G., Almehed, S., Anassontzis, E., Batley, R., Benary, O., Boggild, H., Botner, O., Breuker, H., Burkert, V., Di Ciaccio, A., Cockerill, D., Dagan, S., Dahl-Jensen, E., Dahl-Jensen, I., Damgaard, G., Evans, W. M., Fabjan, C. W., Gordon, H., Hallgren, A., Heck, B., Hilke, H. J., Jarlskog, G., Jeffreys, P., Killian, T., Kourkoumelis, C., Lans, J. V. D., Lissauer, D., Lörstad, B., Ludlam, T., McCubbin, N. A., Mannelli, I., Mjörnmark, U., Molzon, W., Nielsen, Børge Svane, Oren, Y., Palmer, R. B., Rahm, D. C., Rehak, P., Resvanis, L. K., Rosselet, L., Rosso, E., Rudge, A., Schindler, R. H., Schistad, B., Stumer, I., Willis, W. J., Winik, M., Witzeling, W. & Woody, C., 1 aug. 1986, I : Physica Scripta. 34, 2, s. 106-110 5 s.. Publikation: Bidrag til tidsskrift › Tidsskriftartikel › Forskning › fagfællebedømt ...
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A reduction in chronaxie occurs during reinnervation. The published values for chronaxie have a wide range. If chronaxie is the ... The chronaxie times of grey matter were reported as being 380 +/- 191 ms and 200±700 ms. Interpretations of chronaxie times are ... Chronaxie varies across different types of tissue: fast-twitch muscles have a lower chronaxie, slow-twitch muscles have a ... Buchanan D. N.; Garven H. S. D. (1926). "Chronaxie in tetany. The effect on the chronaxie of thyreoparathyreoidectomy, the ...
Chronaxie Ashley, et al. "Determination of the Chronaxie and Rheobase of Denervated Limb Muscles in Conscious Rabbits". ... The x-intercept of the Weiss equation is equal to b x c, or rheobase times chronaxie. This equation suggests that a graph of ... Measurement of chronaxie and rheobase in sural sensory fibers has revealed mild reductions in excitability in diabetics, as ... Mathematically, rheobase is equivalent to half the current that needs to be applied for the duration of chronaxie, which is a ...
She was the author of many works on Chronaxie and the influence of insulin on the autonomic nervous system and became a ... Hurynowicz, J. (1933). Über die normale und pathologische Chronaxie der vasomotorischen Nerven. Pogoń. Hurynowicz, J. (1947). ...
While working on her doctorate, she worked in Louis and Marcelle Lapicque's Laboratory of Physiology, investigating chronaxie ...
... so called chronaxie). Typically, chronaxie of neural cells is in the range of 0.1-10 ms, so the sensitivity to electrical ...
Transcutaneous Electro-muscular stimulation Therapy and Relativity of Chronaxie. Invited lecture at International Conference on ...
Marcelle de Heredia Lapicque (1873 - 1960) was a French neurophysiologist known for her research on nerve impulses (chronaxie) ... and the effects of poisons, especially strychnine, on chronaxie. She was in charge of the Laboratoire des Hautes-Études General ...
This theory states that the frequency of the vocal fold vibration is determined by the chronaxie of the recurrent nerve, and ...
Arnab Chakraborty) Chronaxie - The Annual Cultural Festival (Name given by Dr. Arnab Chakraborty) Annual Sports meets ...
Anode break excitation Bioelectricity Biological neuron model Bursting Central pattern generator Chronaxie Frog battery Law of ...
In September 2019 Facebook bought a startup called CTRL-labs that was working on EMG Chronaxie Compound muscle action potential ...
Calcium channel - Ion channel complex through which calcium ions pass Chronaxie - Electrophysiology metric Epithelial sodium ...
Another factor is that cardiac tissue has a chronaxie (response time) of about 3 milliseconds, so electricity at frequencies of ...
... specialist of the nervous system and known for his discovery of the chronaxie. Marcel Mauss (1872-1950), father of French ...
Chronaxie in Frédéric Joliot-Curie page 578 by Michel Pinault (Editions Odile Jacob, 2000) Lapicque L (1907). "Recherches ... chronaxie, its meaning and its measure (1926) Nervous machine (1943) Neuromuscular isochronism and rythmogenic excitability ( ...
CHRONAXY. alternate spelling of chronaxie POOR YORICK. The (dead) jester in Hamlet. The quote referred to is by Hamlet, holding ...
phase-width duration (in µs, i.e.microseconds) or chronaxie being used. ...
Chronaxy - Preferred Concept UI. M0004446. Scope note. The shortest duration of an electrical stimulus where the threshold ...
Matematické základy měření kathodové chronaxie  Lednický, Alois (Sborník Vysoké školy báňské v Ostravě. 1950, roč. 2, s. 37-45 ...
Chronaxie of nerve cell and nerve fiber Active Synonym false false 138475018 Chronaxy of nerve cell and nerve fiber Active ... Chronaxie of nerve cell and nerve fiber, function (observable entity). Code System Preferred Concept Name. Chronaxie of nerve ... Chronaxie of nerve cell and nerve fibre Active Synonym false false 505631016 Chronaxia of nerve cell and nerve fibre Active ... Chronaxie of nerve cell and nerve fiber, function Active Synonym false false ...
... with reference to chronaxie of subordination. American Journal of Physiology, 106, 721-737. Tente links no:* Google ...
value; 【生】chronaxie; duration; 网络释义: chronaxy; time value; Time ... 心理学专业词汇翻译辞典 - MBA智库文档 ... chronaximetry 时值测量法 chronaxy 时值 chronic 慢性的 ... ... 心理学专业词
Found 65 words with the letters ONYX. Find your perfect word for Scrabble or Words with Friends now!
Chronaxie. Sensory Functions. A (alpha). 40-100μs. Predominantly motor neurons. They also have. the following sensory functions ... This is called the chronaxie threshold. It is preferable to keep the pulse width as close to this value for the related nerve ... It can be seen that the stimulation is the most energy efficient at the chronaxie pulse of +- 80μs width as would be expected. ... In the second case even though the total charge transferred to the nerve is the same, because of the chronaxie threshold of 100 ...
keywords = "Calcium imaging, Chronaxie, Electric stimulation, Issue 123, Magnetic stimulation, Neuronal networks, Neuroscience ...
Rheobase/chronaxies (. 10:13. ). *Tetanization (. 12:05. ). *Graph showing Tetanization (. 15:52. ) ...
01 CHRONAXIE 0. Worked example 5. Settlers of Catan - Trading Strategies By Seth Brown.et al. To 4. All these people have one ...
... and chronaxie and accommodation index (AI) measured by the strength-duration curve were evaluated. RESULTS: Both groups showed ... chronaxie values always reported similar values with no differences between groups (p >0.05); Conclusion: Ultrasound-PNM ...
Bourguignon D.G. La chronaxie chez Phomme. Masson etcie; 1923.417 p.. *Verdan C.E. Primary repair of flexor tendons. JBone ...
The effects of shock wave stimulation of mesenchymal stem cells on proliferation, migration, and differentiation in an injectable gelatin matrix for osteogenic regeneration. J Tissue Eng Regen Med. 2020 11; 14(11):1630-1640 ...
Low rheobase and chronaxie values indicate that the electrode is positioned close to the motor point. ... The rheobase (the threshold twitch current over a prolonged pulse duration of 500 μs) and range of chronaxie (electrical ...
galvanický proud;neofaradický proud;chronaxie;reobáze;akomodační kvocient;I/t křivka;denervační syndrom. ... galvanic current;neofaradic current;chronaxy;rheobase;accomodation quotient;Strength-Duration curve;denervation syndrome. ...
Chronaxy [G11.561.175] * Cortical Excitability [G11.561.200] * Dominance, Cerebral [G11.561.225] * Habituation, ...
chronaxy. chronic. chronicle. Chronicles. Chrono. chronogram. chronograph. chronological. chronology. chronometer. chronometry ...
The likesRelated failure of this bifurcation removes to determine the government of osteoporosis chronaxie and EE cytolysis in ...
Fits to the data using standard strength-duration equations were qualitatively similar, but the resulting chronaxie and ...
â ¢ automatic calculation of rheobase, chronaxie as well as accommodation coefficient. ULTRASOUND THERAPY. â ¢ operation ...
1998-02 Axons, but not cell bodies, are activated by electrical stimulation in cortical gray matter I. Evidence from chronaxie ...
On electron microscopy, two forms of synoviocytes are distinguished: sort A and kind B. Lapicque, L: La Chronaxie et ses ...
chromosome, chromosomes, chromous, chromyl, chronaxies, chronaxy, chronic, chronicle, chronicled, chronicler, chroniclers, ...
In the context of long-term hypoestrogenemy threshold of AP appearance was 55,32±7,69%, chronaxy ? 115,09±2,67%, latent period ...
Substance 2 will elucidate a failure chronaxie to shear the phenotype of HF and its individuals over sympathoexcitation to Add ...
Chronaxy [G11.561.175] Chronaxy * Cortical Excitability [G11.561.200] + Cortical Excitability + * Dominance, Cerebral [G11.561. ...
Chronaxy [G11.561.175] Chronaxy * Cortical Excitability [G11.561.200] Cortical Excitability * Dominance, Cerebral [G11.561.225 ...
  • phase-width duration (in µs, i.e.microseconds) or chronaxie being used. (hammernutrition.com)
  • Some conditions affecting intensity and duration thresholds in motor nerves, with reference to chronaxie of subordination. (bvsalud.org)
  • The resulting strength duration curves were analyzed by determining chronaxie and rheobase. (medscape.com)
  • [ 15 ] Both models are described by 2 parameters: the rheobase and the chronaxie. (medscape.com)
  • This is equivalent to measuring one data point of a strength-duration curve to determine chronaxie and rheobase of our preparation. (medunigraz.at)
  • Activation characteristics of the heart and phrenic nerve are different with higher chronaxie for the heart. (medscape.com)
  • In children, rates of response are lower than in adults (less than 20 5 years or even no response 1 year) because of the immaturity of the fibers (higher chronaxie in non-myelinized fibers). (findbinaryoption.com)
  • 3) Most, and perhaps all, CNS myelinated fibers have chronaxies of 50-100 musec. (nih.gov)
  • When gray matter is stimulated, the chronaxie is often 200-700 musec. (nih.gov)