Chronaxy: 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.BooksAction Potentials: Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.Adaptation, Physiological: The non-genetic biological changes of an organism in response to challenges in its ENVIRONMENT.Accommodation, Ocular: 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)Periodicals as Topic: A publication issued at stated, more or less regular, intervals.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Electric Stimulation Therapy: 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.Transcutaneous Electric Nerve Stimulation: 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.Ultrasonic Therapy: 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.Cellular Phone: 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.Pain Threshold: Amount of stimulation required before the sensation of pain is experienced.Pain: An unpleasant sensation induced by noxious stimuli which are detected by NERVE ENDINGS of NOCICEPTIVE NEURONS.Catastrophization: Cognitive and emotional processes encompassing magnification of pain-related stimuli, feelings of helplessness, and a generally pessimistic orientation.Brachial Plexus: 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.Brachial Plexus Neuropathies: 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)Tooth Movement: Orthodontic techniques used to correct the malposition of a single tooth.Galvanic Skin Response: A change in electrical resistance of the skin, occurring in emotion and in certain other conditions.Neon: 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.Skin Physiological Phenomena: The functions of the skin in the human and animal body. It includes the pigmentation of the skin.Brachial Plexus Neuritis: 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)Pediatric Nursing: The nursing specialty concerning care of children from birth to adolescence. It includes the clinical and psychological aspects of nursing care.Quadriceps Muscle: 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.Air Filters: Barriers used to separate and remove PARTICULATE MATTER from air.Electric Stimulation: Use of electric potential or currents to elicit biological responses.Muscle Weakness: 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)Torque: 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.Catheter Ablation: Removal of tissue with electrical current delivered via electrodes positioned at the distal end of a catheter. Energy sources are commonly direct current (DC-shock) or alternating current at radiofrequencies (usually 750 kHz). The technique is used most often to ablate the AV junction and/or accessory pathways in order to interrupt AV conduction and produce AV block in the treatment of various tachyarrhythmias.Ventricular Fibrillation: A potentially lethal cardiac arrhythmia that is characterized by uncoordinated extremely rapid firing of electrical impulses (400-600/min) in HEART VENTRICLES. Such asynchronous ventricular quivering or fibrillation prevents any effective cardiac output and results in unconsciousness (SYNCOPE). It is one of the major electrocardiographic patterns seen with CARDIAC ARREST.Heart Conduction System: An impulse-conducting system composed of modified cardiac muscle, having the power of spontaneous rhythmicity and conduction more highly developed than the rest of the heart.Atrial Fibrillation: Abnormal cardiac rhythm that is characterized by rapid, uncoordinated firing of electrical impulses in the upper chambers of the heart (HEART ATRIA). In such case, blood cannot be effectively pumped into the lower chambers of the heart (HEART VENTRICLES). It is caused by abnormal impulse generation.Body Surface Potential Mapping: Recording of regional electrophysiological information by analysis of surface potentials to give a complete picture of the effects of the currents from the heart on the body surface. It has been applied to the diagnosis of old inferior myocardial infarction, localization of the bypass pathway in Wolff-Parkinson-White syndrome, recognition of ventricular hypertrophy, estimation of the size of a myocardial infarct, and the effects of different interventions designed to reduce infarct size. The limiting factor at present is the complexity of the recording and analysis, which requires 100 or more electrodes, sophisticated instrumentation, and dedicated personnel. (Braunwald, Heart Disease, 4th ed)Electrodes: Electric conductors through which electric currents enter or leave a medium, whether it be an electrolytic solution, solid, molten mass, gas, or vacuum.Electrocardiography: Recording of the moment-to-moment electromotive forces of the HEART as projected onto various sites on the body's surface, delineated as a scalar function of time. The recording is monitored by a tracing on slow moving chart paper or by observing it on a cardioscope, which is a CATHODE RAY TUBE DISPLAY.Patents as Topic: Exclusive legal rights or privileges applied to inventions, plants, etc.Stimulation, Chemical: The increase in a measurable parameter of a PHYSIOLOGICAL PROCESS, including cellular, microbial, and plant; immunological, cardiovascular, respiratory, reproductive, urinary, digestive, neural, musculoskeletal, ocular, and skin physiological processes; or METABOLIC PROCESS, including enzymatic and other pharmacological processes, by a drug or other chemical.Foramen Ovale, Patent: A condition in which the FORAMEN OVALE in the ATRIAL SEPTUM fails to close shortly after birth. This results in abnormal communications between the two upper chambers of the heart. An isolated patent ovale foramen without other structural heart defects is usually of no hemodynamic significance.Physical Stimulation: Act of eliciting a response from a person or organism through physical contact.Regional Blood Flow: The flow of BLOOD through or around an organ or region of the body.Lidocaine: A local anesthetic and cardiac depressant used as an antiarrhythmia agent. Its actions are more intense and its effects more prolonged than those of PROCAINE but its duration of action is shorter than that of BUPIVACAINE or PRILOCAINE.Anesthesiology: A specialty concerned with the study of anesthetics and anesthesia.Research: Critical and exhaustive investigation or experimentation, having for its aim the discovery of new facts and their correct interpretation, the revision of accepted conclusions, theories, or laws in the light of newly discovered facts, or the practical application of such new or revised conclusions, theories, or laws. (Webster, 3d ed)Research Personnel: Those individuals engaged in research.Research Support as Topic: Financial support of research activities.Biomedical Research: Research that involves the application of the natural sciences, especially biology and physiology, to medicine.Resuscitation: The restoration to life or consciousness of one apparently dead. (Dorland, 27th ed)Dictionaries, MedicalDictionaries as Topic: Lists of words, usually in alphabetical order, giving information about form, pronunciation, etymology, grammar, and meaning.Dictionaries, ChemicalRecurrence: The return of a sign, symptom, or disease after a remission.Terminology as Topic: The terms, expressions, designations, or symbols used in a particular science, discipline, or specialized subject area.Phonetics: The science or study of speech sounds and their production, transmission, and reception, and their analysis, classification, and transcription. (Random House Unabridged Dictionary, 2d ed)Dictionary

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)

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 ...
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 ...
ATCC offers a variety of extremophiles including archaea, halophiles, acidophiles, thermophiles, psychrophiles, and alkaliphiles.
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 ...
While working on her doctorate, she worked in Louis and Marcelle Lapicque's Laboratory of Physiology, investigating chronaxie ...
Ion channels Calcium channels Potassium channels Resting ion channels Epithelial sodium channel Chronaxie Jessell TM, Kandel ER ...
... so called chronaxie). Typically, chronaxie of neural cells is in the range of 0.1-10 ms, so the sensitivity to electrical ...
... chronaxie) and the effects of poisons, especially strychnine, on chronaxie. She was in charge of the Laboratoire des Hautes- ...
This theory states that the frequency of the vocal fold vibration is determined by the chronaxie of the recurrent nerve, and ...
Neuroscience portal Anode break excitation Biological neuron model Bursting Central pattern generator Chronaxie Frog battery ...
Another factor is that cardiac tissue has a chronaxie (response time) of about 3 milliseconds, so electricity at frequencies of ...
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 ...
... 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 ...
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 ...
Study Electrotherapy and Pain Modulation flashcards from Connor Vankouwenberg
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 ...
I. Evidence from chronaxie measurements. Exp. Brain Res. 118, 477-488. doi: 10.1007/s002210050304 ...
CHRONAXIE. Term. 71. _____ is the minimum volts necessary to excite a nerve.. ...
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 ...
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 ...
Spiritoso drabbled ciscoes defends dozier parallelly neighbouring expostulated Cyril plim introrsely mincing chronaxie. Skell ...
Sample Decks: Timing Cycles, Arrhythmias, Rheobase And Chronaxie Time Show Class * Cardiology ...
A comparison of chronaxies for ventricular fibrillation induction, defibrillation, and cardiac stimulation: unexpected findings ...
  • 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)
  • figures from recordings of solitary fiber reactions to electric excitement, including threshold, comparative CB-839 distributor pass on, jitter, and chronaxie. (ecologicalsgardens.com)
  • 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)
  • 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)
  • The true secret metric that electrophysiologists use to describe the relationship between the result of pulse length and recent is chronaxie, an idea much like what we engineers call the process time continual. (timeblog.net)