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.
Lists of words, usually in alphabetical order, giving information about form, pronunciation, etymology, grammar, and meaning.
Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.
The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.
The dioptric adjustment of the EYE (to attain maximal sharpness of retinal imagery for an object of regard) referring to the ability, to the mechanism, or to the process. Ocular accommodation is the effecting of refractive changes by changes in the shape of the CRYSTALLINE LENS. Loosely, it refers to ocular adjustments for VISION, OCULAR at various distances. (Cline et al., Dictionary of Visual Science, 4th ed)
A publication issued at stated, more or less regular, intervals.
Elements of limited time intervals, contributing to particular results or situations.
Application of electric current in treatment without the generation of perceptible heat. It includes electric stimulation of nerves or muscles, passage of current into the body, or use of interrupted current of low intensity to raise the threshold of the skin to pain.
The use of specifically placed small electrodes to deliver electrical impulses across the SKIN to relieve PAIN. It is used less frequently to produce ANESTHESIA.
The use of focused, high-frequency sound waves to produce local hyperthermia in certain diseased or injured parts of the body or to destroy the diseased tissue.
Analog or digital communications device in which the user has a wireless connection from a telephone to a nearby transmitter. It is termed cellular because the service area is divided into multiple "cells." As the user moves from one cell area to another, the call is transferred to the local transmitter.
Amount of stimulation required before the sensation of pain is experienced.
An unpleasant sensation induced by noxious stimuli which are detected by NERVE ENDINGS of NOCICEPTIVE NEURONS.
Cognitive and emotional processes encompassing magnification of pain-related stimuli, feelings of helplessness, and a generally pessimistic orientation.
Therapeutic modalities frequently used in PHYSICAL THERAPY SPECIALTY by PHYSICAL THERAPISTS or physiotherapists to promote, maintain, or restore the physical and physiological well-being of an individual.
Instructional materials used in teaching.
The branch of pharmacology that deals directly with the effectiveness and safety of drugs in humans.
The direct struggle between individuals for environmental necessities or for a common goal.
The auxiliary health profession which makes use of PHYSICAL THERAPY MODALITIES to prevent, correct, and alleviate movement dysfunction of anatomic or physiological origin.
A form of interactive entertainment in which the player controls electronically generated images that appear on a video display screen. This includes video games played in the home on special machines or home computers, and those played in arcades.
The large network of nerve fibers which distributes the innervation of the upper extremity. The brachial plexus extends from the neck into the axilla. In humans, the nerves of the plexus usually originate from the lower cervical and the first thoracic spinal cord segments (C5-C8 and T1), but variations are not uncommon.
Diseases of the cervical (and first thoracic) roots, nerve trunks, cords, and peripheral nerve components of the BRACHIAL PLEXUS. Clinical manifestations include regional pain, PARESTHESIA; MUSCLE WEAKNESS, and decreased sensation (HYPESTHESIA) in the upper extremity. These disorders may be associated with trauma (including BIRTH INJURIES); THORACIC OUTLET SYNDROME; NEOPLASMS; NEURITIS; RADIOTHERAPY; and other conditions. (From Adams et al., Principles of Neurology, 6th ed, pp1351-2)
Orthodontic techniques used to correct the malposition of a single tooth.
A change in electrical resistance of the skin, occurring in emotion and in certain other conditions.
Neon. A noble gas with the atomic symbol Ne, atomic number 10, and atomic weight 20.18. It is found in the earth's crust and atmosphere as an inert, odorless gas and is used in vacuum tubes and incandescent lamps.
The functions of the skin in the human and animal body. It includes the pigmentation of the skin.
A syndrome associated with inflammation of the BRACHIAL PLEXUS. Clinical features include severe pain in the shoulder region which may be accompanied by MUSCLE WEAKNESS and loss of sensation in the upper extremity. This condition may be associated with VIRUS DISEASES; IMMUNIZATION; SURGERY; heroin use (see HEROIN DEPENDENCE); and other conditions. The term brachial neuralgia generally refers to pain associated with brachial plexus injury. (From Adams et al., Principles of Neurology, 6th ed, pp1355-6)
An occupational discipline founded by D.D. Palmer in the 1890's based on the relationship of the spine to health and disease.
Procedures used by chiropractors to treat neuromusculoskeletal complaints.
Diseases of the muscles and their associated ligaments and other connective tissue and of the bones and cartilage viewed collectively.
The MUSCLES, bones (BONE AND BONES), and CARTILAGE of the body.
Discomfort stemming from muscles, LIGAMENTS, tendons, and bones.
Diseases caused by factors involved in one's employment.
Authoritative treatises on drugs and preparations, their description, formulation, analytic composition, physical constants, main chemical properties used in identification, standards for strength, purity, and dosage, chemical tests for determining identity and purity, etc. They are usually published under governmental jurisdiction (e.g., USP, the United States Pharmacopoeia; BP, British Pharmacopoeia; P. Helv., the Swiss Pharmacopoeia). They differ from FORMULARIES in that they are far more complete: formularies tend to be mere listings of formulas and prescriptions.
The nursing specialty concerning care of children from birth to adolescence. It includes the clinical and psychological aspects of nursing care.
The quadriceps femoris. A collective name of the four-headed skeletal muscle of the thigh, comprised of the rectus femoris, vastus intermedius, vastus lateralis, and vastus medialis.
Barriers used to separate and remove PARTICULATE MATTER from air.
Use of electric potential or currents to elicit biological responses.
A vague complaint of debility, fatigue, or exhaustion attributable to weakness of various muscles. The weakness can be characterized as subacute or chronic, often progressive, and is a manifestation of many muscle and neuromuscular diseases. (From Wyngaarden et al., Cecil Textbook of Medicine, 19th ed, p2251)
The rotational force about an axis that is equal to the product of a force times the distance from the axis where the force is applied.

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 ...
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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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 ...
Calcium channels Chronaxie Epithelial sodium channel Ion channels Resting ion channels Jessell TM, Kandel ER, Schwartz JH (2000 ...
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 ...
Anode break excitation Bioelectricity Biological neuron model Bursting Central pattern generator Chronaxie Frog battery Neural ...
In September 2019 Facebook bought a startup called CTRL-labs that was working on EMG Chronaxie Compound muscle action potential ...
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 ( ...
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 ...
Tympanic membrane displacement (TMD) technique, proposed nearly twenty years ago by Marchbanks [16] exploits the effect of intracranial pressure on the acoustic reflex, i.e. a reflex contraction of the stapedius and tensor tympani muscles in response to a sound. Normally, vibrations of the tympanic membrane (eardrum) elicited by acoustic stimuli are transmitted through the chain of ossicles (malleus, uncus, and stapes) in the middle ear to the oval window of the cochlea. Vibrations of the footplate of stapes transmit through the oval window to the perilymph, which in turn causes the endolymph, the basilar membrane, and the organ of Corti to vibrate, activating ultimately the acoustic sensor cells, the inner hair cells of the organ of Corti. The transfer function of this complex mechanical system under physiological conditions is modulated by the action of two small muscles of the middle ear, the tensor tympani and stapedius. The tensor tympani arises from the cartilaginous portion of the ...
... has been a subject of study since as early as 4,000 B.C. In the early B.C. years, most studies were of different natural sedatives like alcohol and poppy plants. In 1700 B.C., the Edwin Smith surgical papyrus was written. This papyrus was crucial in understanding how the ancient Egyptians understood the nervous system. This papyrus looked at different case studies about injuries to different parts of the body, most notably the head. Beginning around 460 B.C., Hippocrates began to study epilepsy, and theorized that it had its origins in the brain. Hippocrates also theorized that the brain was involved in sensation, and that it was where intelligence was derived from. Hippocrates, as well as most ancient Greeks, believed that relaxation and a stress free environment was crucial in helping treat neurological disorders. In 280 B.C., Erasistratus of Chios theorized that there were divisions in the vestibular processing the brain, as well as deducing from observation that sensation was ...
Before the local protein synthesis hypothesis gained significant support, there was general agreement that the protein synthesis underlying L-LTP occurred in the cell body. Further, there was thought that the products of this synthesis were shipped cell-wide in a nonspecific manner. It thus became necessary to explain how protein synthesis could occur in the cell body without compromising LTP's input specificity. The synaptic tagging hypothesis attempts to solve the cell's difficult problem of synthesizing proteins in the cell body but ensuring they only reach synapses that have received LTP-inducing stimuli. The synaptic tagging hypothesis proposes that a "synaptic tag" is synthesized at synapses that have received LTP-inducing stimuli, and that this synaptic tag may serve to capture plasticity-related proteins shipped cell-wide from the cell body.[47] Studies of LTP in the marine snail Aplysia californica have implicated synaptic tagging as a mechanism for the input-specificity of LTP.[48][49] ...
... s can be inhibited themselves through a signaling process called "depolarized-induced suppression of inhibition (DSI)" in CA1 pyramidal cells and cerebellar Purkinje cells.[10][11] In a laboratory setting step depolarizations the soma have been used to create DSIs, but it can also be achieved through synaptically induced depolarization of the dendrites. DSIs can be blocked by ionotropic receptor calcium ion channel antagonists on the somata and proximal apical dendrites of CA1 pyramidal cells. Dendritic inhibitory postsynaptic potentials can be severely reduced by DSIs through direct depolarization. Along these lines, inhibitory postsynaptic potentials are useful in the signaling of the olfactory bulb to the olfactory cortex.[12] EPSPs are amplified by persistent sodium ion conductance in external tufted cells. Low-voltage activated calcium ion conductance enhances even larger EPSPs. The hyperpolarization activated nonselective cation conductance decreases EPSP ...
Chronaxie. *Frog battery. *Neural accommodation. *Single-unit recording. *Soliton model in neuroscience ...
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 ...
The irritability of the vagus nerves of dogs, as shown by the rheobase and chronaxie, in some types of tetany; and their relief ... The irritability of the vagus nerves of dogs, as shown by the rheobase and chronaxie, in some types of tetany; and their relief ...
McGraw-Hill Dictionary of Scientific & Technical... Explanation of Chronaxie ... Find out information about Chronaxie. The time interval required to excite a tissue by an electric current of twice the ... Chronaxie. Also found in: Dictionary, Medical, Wikipedia.. Related to Chronaxie: rheobase. chronaxie. [′krä‚nak·sē] (physiology ... Subordinative chronaxie is generally more brief than constitutional chronaxie.. The chronaxie of excitable tissues varies; it ...
Chronaxie (1929); Equilibrium, Animal (1929); Nerve in part (1929). Luis W. Alvarez. Accelerators, Particle, in part (1956). ...
Keywords : Action potentials; Physiological adaptation; Chronaxy; Nerve tissue; Ion channels. · abstract in Portuguese · text ... chronaxy; nerve impulse. We conducted a search of articles with a wide time window from 1931 to 2010 and books from 1791 to ... chronaxie, accommodation, and adaptation. CONCLUSION: A stimulus that creates AP, if applied consistently, can reduce 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 ...
Study Electrotherapy and Pain Modulation flashcards from Connor Vankouwenberg
I. Evidence from chronaxie measurements. Exp. Brain Res. 118, 477-488. doi: 10.1007/s002210050304 ...
What is chronaxie?. Duration of a stimulus 2xs the rheobase (capable of eliciting a minimal detectable motor response. ... Healthy = less than 1ms Denervated = prolonged chronaxie (10-20ms). What are the 3 levels of response to electrical stimulation ...
the propagation of action potentials along myelinated axons from one node of Ranvier to the next node, increasing the conduction velocity of action potentials without needing to increase the diameter of an axon. Larger diameter = faster impulse. is the principle that the strength by which a nerve or muscle fiber responds to a stimulus is not dependent on the strength of the stimulus. ...
CHRONAXIE. Term. 71. _____ is the minimum volts necessary to excite a nerve.. ...
The linear fit of the sinusoidal (R² = 0.9913) and trapezoidal thresholds (R² = 0.9947) reveals chronaxie times of 504 μs and ... It was found that the PNS threshold parameters (i.e., field threshold amplitude and chronaxie of the stimulation threshold ... Recoskie, B. J., Scholl, T. J. & Chronik, B. A. The discrepancy between human peripheral nerve chronaxie times as measured ... as a function of pulse duration were assessed in terms of linearity with a linear fit and in terms of the chronaxie times (i.e ...
Irnich, W. (1980). The chronaxie time and its practical importance. Pacing Clin. Electrophysiol. 3, 292-301. doi: 10.1111/j. ... Irnich, W. (2010). The terms "chronaxie" and "rheobase" are 100 years old. Pacing Clin. Electrophysiol. 33, 491-496. doi: ... In the future, studies addressing the calculation of rheobase and chronaxie and stimulation with variable pulse parameters ...
Doctrine of Chronaxy; Consciousness & Nerve Fiber Radiation; Soul as Harmony of the body; Neural Frequencies & Ether Waves.. ...
8 chronaxy 108. 8 Chrysler 108. 8 chunters 108. 8 circuity 108 ...
The "chronaxie" is that duration which requires a doubling of the rheobase current. The chronaxie time constant dc is thus ... Using the available data on measured defibrillation chronaxie time constants, dc =2.7±0.9 ms is the average chronaxie value for ... Assuming a chronaxie of 2.7 ms and an inter-electrode resistance of 50 Ω, the optimum capacitance value from Eq. 32 is 43 μF. ... 5 that if the chronaxie value dc were zero, the effective current Ipe would simply be Iave, the average current of a monophasic ...
change in chronaxie with rats. However, those experiments could be either not verified in later experiments, could not be ...
Chronaxie Measurements in Patterned Neuronal Cultures from Rat Hippocampus.. Stern S, Agudelo-Toro A, Rotem A, Moses E, Neef A. ...
Holsheimer J, Dijkstra EA, Demeulemeester H, et al. Chronaxie calculated from current-duration and voltage-duration data. J ... and chronaxie is the stimulus duration that elicits a response when the stimulus strength is twice that of rheobase. But, of ... having similarities to the concepts of rheobase and chronaxie in neurophysiology 60, 61, might be promising, where rheobase is ...
Chronaxie. 71. 73. Electrotonic potential. 69. 74. F wave. 66. 75. Multielectrode array. 65. ...
phase-width duration (in µs, i.e.microseconds) or chronaxie being used.Technical Characteristics*4 Independent Channels (8 ...
phase-width duration (in µs, i.e.microseconds) or chronaxie being used. Technical Characteristics *4 Independent Channels (8 ...
... preceded by drop in chronaxie. [Motion pictures.] Case 3 ...
EOLa and citral (at 60 and 30 g/mL, values close to their respective IC50 for CAP blockade) significantly increased chronaxy ... EOLs and thymol in the concentration of 60 g/mL significantly increased chronaxie and rheobase. The conduction velocities of ...
In a significant aspect of the present invention, a preferred device periodically determines the chronaxie and rheobase ... Additionally, a larger chronaxie may result from the leads larger surface area ring electrode which is typically used for a CS ... And thus, the chronaxie value (in milliseconds) may be determined by the following equation with measurements made at duration ... The chronaxie and rheobase may be calculated using the present device. As described below, this calculation may be accomplished ...
Several measurements were used to characterized neuromuscular function, including twitch characteristics, chronaxie, tetanic ...
1) modification of the basic chronaxie, (2) alteration of normal impulse amplitude, wave length, force intensity, and/or (3) ...
Safety and Feasibility of a Neuromuscular Electrical Stimulation Chronaxie-Based Protocol in Critical Ill Patients: A ... There was a significant difference between the maximum gluteal chronaxie: 550 (±150) microseconds versus quadriceps: 300 (±90) ...
T0 =Chronaxie (pulse width at two times the Rheobase value).. The S-D curves shown in FIG. 1 are in accordance with this ...
Mean (SD) chronaxie measured before and after general anaesthesia was 0.32 (0.17) ms (95% CI 0.26-0.38 ms) and 0.29 (0.13) ms ( ... Under anaesthesia, rheobase values increased by an average of 20% (p = 0.05), but chronaxie values did not change significantly ... The effects of general anaesthesia on nerve-motor response characteristics (rheobase and chronaxie) to peripheral nerve ... and chronaxie (the minimum time for a stimulus twice the rheobase to elicit nerve activity). Nerve stimulation was used to ...
  • Lapicque used constant-current, capacitor-discharge pulses to obtain chronaxie for a wide variety of excitable tissues. (wikipedia.org)
  • Lapicque's investigations on the chronaxie of excitable tissues. (yale.edu)
  • This example of the preponderating influence which the condition of the skin and the underlying tissues may exert compels caution in judging the results of chronaxie measurements by percutaneous stimulation. (wikipedia.org)
  • Chronaxie times decreased and rheobase current values increased when retrograde nerve fibre degeneration was simulated. (scielo.org.za)
  • The terms chronaxie and rheobase were first coined in Louis Lapicque's famous paper on Définition expérimentale de l'excitabilité that was published in 1909. (wikipedia.org)
  • Chronaxie is the tissue-excitability parameter that permits choice of the optimum stimulus pulse duration for stimulation of any excitable tissue. (wikipedia.org)
  • Chronaxie (c) is the Lapicque descriptor of the stimulus pulse duration for a current of twice rheobasic (b) strength, which is the threshold current for an infinitely long-duration stimulus pulse. (wikipedia.org)
  • The minimum energy occurs with a pulse duration equal to chronaxie. (wikipedia.org)
  • Mathematically, rheobase is equivalent to half the current that needs to be applied for the duration of chronaxie, which is a strength-duration time constant that corresponds to the duration of time that elicits a response when the nerve is stimulated at twice rheobasic strength. (wikipedia.org)
  • The strength-duration time constant (chronaxie) and rheobase are parameters that describe the strength-duration curve-the curve that relates the intensity of a threshold stimulus to its duration. (wikipedia.org)
  • His equation for determining current I: I = b ( 1 + c d ) , {\displaystyle I=b(1+{c \over d}\,),} where b relates to the rheobase value and c relates to the chronaxie value over duration d. (wikipedia.org)
  • The electrical charge Q can be calculated with the following equation: Q = b ( d + c ) {\displaystyle Q=b(d+c)} or Q = I d , {\displaystyle Q=Id,} again, where I is the current is measured in amperes multiplied by duration d. b relates to the rheobase value and c relates to the chronaxie value. (wikipedia.org)
  • phase-width duration (in µs, i.e.microseconds) or chronaxie being used. (hammernutrition.com)
  • In a significant aspect of the present invention, a preferred device periodically determines the chronaxie and rheobase corresponding to a strength-duration curve for each site and sets initial controlled energy levels accordingly. (google.com)
  • There were analyzed the threshold chronaxy, latent period, duration and amplitude of the action potential (AP) of VR. (vpbm.com.ua)
  • It is the specific free Calling for Help: care of disease neck and is particularly one chronaxie of the congestive compensatory effects. (adams-farm.com)
  • heart in patients with congestive uptake completion: chronaxie of translational aggregation Qtc heart messenger. (worldclassbows.com)
  • chronaxie The shortest time required for excitation of a nerve when the electrical stimulus is twice the threshold intensity required to elicit a response if applied over a pro- longed period. (oilforexprofits.com)
  • As to the irreversible but not cell death type block was not due to threshold change which was confirmed by measurement of chronaxy in crayfish giant axon before and after lidocaine application. (nii.ac.jp)
  • The measurement of chronaxie by means of chronaximetry was formerly a common means of studying man's locomotor activity. (thefreedictionary.com)
  • Chronaxie varies across different types of tissue: fast-twitch muscles have a lower chronaxie, slow-twitch muscles have a higher one. (wikipedia.org)
  • Constitutional chronaxie is relevant to tissue exclusive of the tissue's neural relationship with the body. (thefreedictionary.com)
  • Subordinative chronaxie is relevant to tissue in its natural relationship with the body, and primarily with the central nervous system, which regulates the tissue's activity. (thefreedictionary.com)
  • Among the different types of muscle tissue, skeletal striated muscles have the briefest chronaxie. (thefreedictionary.com)
  • Chronaxie is the minimum time required for an electric current double the strength of the rheobase to stimulate a muscle or a neuron. (wikipedia.org)
  • Consequently, changes in subordinative chronaxie, for example, in that of muscles, reflect changes both in the given muscle and in the central nervous system. (thefreedictionary.com)
  • The chronaxie of the heart muscle is more prolonged, and that of the smooth muscles is the most prolonged. (thefreedictionary.com)
  • muscle atrophy and late (3 months) return of motor function, preceded by drop in chronaxie. (thejns.org)
  • The chronaxie measured from the S/D curve was about 1.0 ms, similar to that obtained for muscle membranes. (biomedcentral.com)
  • Chronaxie: 0.07 ms vs 0.08 ms. 2) Muscle contraction parameters: Peak tension: 58.5±5.1 g vs 48.3±4.3 g (P =0.19). (scienceopen.com)
  • Chronaxie is dependent on the density of voltage-gated sodium channels in the cell, which affect that cell's excitability. (wikipedia.org)
  • Measurements on the canine heart in situ with block, carried out with currents pulses of rectangular configuration, revealed that, when the Furman method is used, chronaxy and rheobase of the myocardium are dependent on the position of the electrodes. (uu.nl)
  • As mentioned, the two important points on the curve are rheobase (b) and chronaxie (c), which correlates to twice the rheobase (2b). (wikipedia.org)
  • It has been reported that large-diameter myelinated axons have chronaxie times ranging from 50 to 100 µs and 30 to 200 µs, and neuronal cell bodies and dendrites have chronaxie times ranging from 1 to 10 ms or even up to 30 ms. The chronaxie times of grey matter were reported as being 380 +/- 191 ms and 200±700 ms. Interpretations of chronaxie times are further confounded by additional factors. (wikipedia.org)
  • The chronaxie times reported for soma and dendrites have been established using intracellular pulses that cannot be readily extrapolated to extra- cellular stimuli. (wikipedia.org)
  • The x-intercept of the Weiss equation is equal to b x c, or rheobase times chronaxie. (wikipedia.org)
  • In psychological tests, it has been determined that the time between the nervous impulse and reaction (chronaxie) takes 3-4 times longer than it would in an adult. (uskbtc.com)
  • Chronaxie values increase resulting from hyperventilation can be ascribed to a change in skin impedance, the physiological factors responsible for this change being under the influence of the autonomic nervous system. (wikipedia.org)
  • Chronaxie values were determined for upper extremity musculature, but only finger flexors were intact bilaterally for all children and these were chosen for NMES. (acpoc.org)
  • Notice that the chronaxie (c) is not explicitly present here. (wikipedia.org)
  • chronaxie: The nutritional zero through which application is from the efficacy to the taste. (ajw-service.de)