scholarly journals V. On the "blaze currents" of the frog's eyeball

In a recent communication to the Society I have stated that the normal electrical response of the eye to light consists in a current traversing the eye ball in a positive direction, i. e . from fundus to cornea, and that a similar positive response is aroused by meachanical and by electrical stimuli, whatever be the direction of the latter. I have designated this positive response to non-luminous stimuli as the retainal discharge or blaze. With reference to electrical stimulation, its most characteristic from is when it occurs in the same dorection as the current by which it is excited, i. e . when it cannot be polarisation counter-current. It is in such case analogous with the discharge of an electrical organ excited by an electrical current in the direction of normal discharge, and, indeed, it may be of such magnitued as to lead an observer to regard retain in the light of an electrical organ.

1985 ◽  
Vol 93 (3) ◽  
pp. 385-389 ◽  
Author(s):  
Jack A. Vernon ◽  
James A. Fenwick

Various electrical stimuli were tested for their ability to suppress or relieve severe tinnitus. Stimulation was applied transdermally by electrodes placed on the preauricular and postauricular regions and on the two mastoids. Of the 50 patients tested, only 14 (28%) obtained relief that met the criterion of a reduction in the tinnitus by 40% or more. When relief was obtained, it usually extended for several hours into the poststimulation period. There was only one positive response (2%) In the placebo trial, which was administered to all patients. It was concluded that transdermal electrical stimulation such as that used in this research Is not a practical therapeutic procedure for the relief of tinnitus.


1962 ◽  
Vol 39 (1) ◽  
pp. 119-128 ◽  
Author(s):  
R. W. MURRAY

1. The ampullae of Lorenzini are sensitive to weak electrical stimuli which presumably cause currents to flow along the jelly-filled tubes of the sense organ. Increase of the resting frequency occurs when the tube-opening is made negative to the capsule, and inhibition when the opening is positive, with opposite after-effects in each case. Adaptation is three-quarters complete in about 5 sec. 2. When the stimulus is applied as a voltage gradient in the water overlying the ampullae, the threshold for the most sensitive units is 1 µV./cm., which represents a current along the tube of less than 5 x 10-11 A. 3. When the stimulus is applied as a current directly to the tube opening, the threshold for the most sensitive units is 4 x 10-10 A. 4. Changes in the salinity of the water at the tube opening are also effective, the threshold being about 3%. Dilution causes excitation, and concentration causes inhibition. The response is not due to the osmotic differences, and so probably results from potentials established at the jelly-water interface.


Catalysts ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 62
Author(s):  
Won-Yong Jeon ◽  
Seyoung Mun ◽  
Wei Beng Ng ◽  
Keunsoo Kang ◽  
Kyudong Han ◽  
...  

Enzymatic biofuel cells (EBFCs) have excellent potential as components in bioelectronic devices, especially as active biointerfaces to regulate stem cell behavior for regenerative medicine applications. However, it remains unclear to what extent EBFC-generated electrical stimulation can regulate the functional behavior of human adipose-derived mesenchymal stem cells (hAD-MSCs) at the morphological and gene expression levels. Herein, we investigated the effect of EBFC-generated electrical stimulation on hAD-MSC cell morphology and gene expression using next-generation RNA sequencing. We tested three different electrical currents, 127 ± 9, 248 ± 15, and 598 ± 75 nA/cm2, in mesenchymal stem cells. We performed transcriptome profiling to analyze the impact of EBFC-derived electrical current on gene expression using next generation sequencing (NGS). We also observed changes in cytoskeleton arrangement and analyzed gene expression that depends on the electrical stimulation. The electrical stimulation of EBFC changes cell morphology through cytoskeleton re-arrangement. In particular, the results of whole transcriptome NGS showed that specific gene clusters were up- or down-regulated depending on the magnitude of applied electrical current of EBFC. In conclusion, this study demonstrates that EBFC-generated electrical stimulation can influence the morphological and gene expression properties of stem cells; such capabilities can be useful for regenerative medicine applications such as bioelectronic devices.


2009 ◽  
Vol 110 (6) ◽  
pp. 1300-1303 ◽  
Author(s):  
Mario F. Dulay ◽  
Dona K. Murphey ◽  
Ping Sun ◽  
Yadin B. David ◽  
John H. R. Maunsell ◽  
...  

Cortical mapping with electrical stimulation (ES) in neurosurgical patients typically involves the manually controlled delivery of suprathreshold electrical current to a discrete area of the brain. Limited numbers of trials and imprecise current delivery methods increase the variability of the behavioral response and make it difficult to collect quantitative mapping data, which is especially important in research studies of human cortical function. To overcome these limitations, the authors developed a method for computer-controlled delivery of defined electrical current to implanted intracranial electrodes. They demonstrate that stimulation can be time locked to a behavioral task to rapidly and systematically measure the detection threshold for ES in human visual cortex over many trials. Computer-controlled ES is well suited for the systematic and quantitative study of the function of virtually any region of cerebral cortex. It may be especially useful for studying human cortical regions that are not well characterized and for verifying the presence of stimulation-evoked percepts that are difficult to objectively confirm.


1995 ◽  
Vol 269 (6) ◽  
pp. H2031-H2038 ◽  
Author(s):  
J. Xia ◽  
T. L. Little ◽  
B. R. Duling

We have previously shown that conducted vasomotor responses follow patterns that are consistent with a passive spread of electrical current along the length of the arterioles [(Xia and Duling, Am. J. Physiol. 269 (Heart Circ. Physiol. 38): H2022-H2030, 1995]. In this study, we define the cells through which the current flows. Isolated arterioles of hamster cheek pouch were used. The mean resting membrane potential (RMP) for randomly sampled arteriolar cells was -67 mV. When cell types were identified by dye injection, the RMPs were -68 and -67 mV for smooth muscle (SM) and endothelium (EC), respectively. Pulses of KCl induced transient, monophasic depolarizations at the site of stimulation (local), which were conducted decrementally along the length of the arteriole over several millimeters. During electrical conduction, three patterns of responses could be observed, but identical patterns of the conducted electrical responses were always observed in SM and EC. Phenylephrine stimulation also caused transient local and conducted depolarizations in both SM and EC. As with KCl stimuli, shapes of conducted electrical responses were identical in records made in both cell types. The results suggest that SM and EC are electrically coupled both homocellularly and heterocellularly.


2021 ◽  
Vol 877 (1) ◽  
pp. 012047
Author(s):  
Hind M. Ewadh ◽  
Mustafa J. Al Imari ◽  
Sabrean F. Jawad ◽  
Hayfaa A. Mubarak

Abstract A modest quantity of fluoride can increase the mineralization of teeth and reduce their cavities. But the presomerence of fluoride in excess in water can lead to severe disease infertility. In the past few decades, scientists have thus been preoccupied with developing ways to reduce sewage fluoride concentrations and reduce their effects on human health. The present study is aimed at using the technology of electrocoagulation to remove fluoride from polluted water. Tests have been done to examine the elimination of fluoride with a rectangular electrocoagulation cell and examine the impact of the experimental aspects on fluoride extraction, specifically electrical current, electrode spacing, and pH. The authors found that 93% of the fluoride has been extracted using 5mm spaced electrodes with a current density of 2 mA/cm2 and a level of pH of 7 from the polluted water after 20 min of processing. Experimental factors considerably impact the efficacy of fluoride removal. In the acidic environment, greater effectiveness of fluoride removal is being attained. The elimination effectiveness depends directly on the electric current, whereas the distance between poles is adversely linked to fluoride elimination.


2020 ◽  
pp. 833-851
Author(s):  
Poulami Ghosh ◽  
Ankita Mazumder ◽  
Anwesha Banerjee ◽  
D.N. Tibarewala

Loss or impairment in the ability of muscle movement or sensation is called Paralysis which is caused by disruption of communication of nerve impulses along the pathway from the brain to the muscles. One of the principal reasons causing paralysis is Spinal Cord Injury (SCI) and Neurological rehabilitation by using neuro-prostheses, based on Functional Electrical Stimulation (FES) is extensively used for its treatment. Impaired muscles are activated by applying small amplitude electrical current. Electromyography (EMG), the recording of biosignals generated by muscle activity during the application of FES can be used as the control signal for FES based rehabilitative devices. This method is predominantly used for restoring upper extremity functioning (wrist, hand, elbow, etc.), standing, walking (speed, pattern) in stroke patients. FES, collaborated with conventional methods, has the potential to be utilized as a useful tool for rehabilitation and restoration of muscle strength, metabolic responses etc. in paralyzed patients.


1989 ◽  
Vol 100 (4) ◽  
pp. 345-347 ◽  
Author(s):  
Ian M. Windmill ◽  
Serge A. Martinez ◽  
Christopher B. Shields ◽  
Markku Paloheimo

Facial nerve stimulation by electrical current is painful and tends to discourage serial studies. Transcutaneous magnetic stimulation of the facial nerve is painless, easily reproducible, and elicits facial muscle responses identical to electrical stimulation.


2011 ◽  
Vol 2 ◽  
pp. 727-733 ◽  
Author(s):  
Tchavdar N Todorov ◽  
Daniel Dundas ◽  
Anthony T Paxton ◽  
Andrew P Horsfield

We give a physical interpretation of the recently demonstrated nonconservative nature of interatomic forces in current-carrying nanostructures. We start from the analytical expression for the curl of these forces, and evaluate it for a point defect in a current-carrying system. We obtain a general definition of the capacity of electrical current flow to exert a nonconservative force, and thus do net work around closed paths, by a formal noninvasive test procedure. Second, we show that the gain in atomic kinetic energy over time, generated by nonconservative current-induced forces, is equivalent to the uncompensated stimulated emission of directional phonons. This connection with electron–phonon interactions quantifies explicitly the intuitive notion that nonconservative forces work by angular momentum transfer.


1975 ◽  
Vol 38 (1) ◽  
pp. 198-209 ◽  
Author(s):  
R. W. Knighton

1. To show conclusively that the electrically evoked retinal response (EERG) is in fact an electrically evoked component of the usual ERG, it is necessary to show that the two responses have the same intraretinal pattern of current generators. A method for determining when two responses have the same origin has been developed. This method utilizes measurements from a single microelectrode penetrating the retina. 2. The method was sensitive enough to detect differences in the origins of two responses when they were present. 3. The EERG had the same intraretinal origin as the PII component of the ERG, and thus is the PII component evoked by electricity rather than by light. 4. The hypothesis that electrical stimuli act on the synaptic terminals of the photoreceptor cells predicts that electrical current will evoke components of the ERG. The fact that the EERG is an electrically evoked component of the ERG fulfills that prediction.


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