Electrical stimulation of retinal neurons in epiretinal and subretinal configuration using a multicapacitor array

2012 ◽  
Vol 107 (10) ◽  
pp. 2742-2755 ◽  
Author(s):  
Max Eickenscheidt ◽  
Martin Jenkner ◽  
Roland Thewes ◽  
Peter Fromherz ◽  
Günther Zeck
Keyword(s):  
Electrical Stimulation ◽  
Ganglion Cells ◽  
Ex Vivo ◽  
Biophysical Model ◽  
Retinal Neurons ◽  
Direct Stimulation ◽  
Tungsten Electrode ◽  
Partial Restoration ◽  
Low Amplitude ◽  
Stimulation Of

Electrical stimulation of retinal neurons offers the possibility of partial restoration of visual function. Challenges in neuroprosthetic applications are the long-term stability of the metal-based devices and the physiological activation of retinal circuitry. In this study, we demonstrate electrical stimulation of different classes of retinal neurons with a multicapacitor array. The array—insulated by an inert oxide—allows for safe stimulation with monophasic anodal or cathodal current pulses of low amplitude. Ex vivo rabbit retinas were interfaced in either epiretinal or subretinal configuration to the multicapacitor array. The evoked activity was recorded from ganglion cells that respond to light increments by an extracellular tungsten electrode. First, a monophasic epiretinal cathodal or a subretinal anodal current pulse evokes a complex burst of action potentials in ganglion cells. The first action potential occurs within 1 ms and is attributed to direct stimulation. Within the next milliseconds additional spikes are evoked through bipolar cell or photoreceptor depolarization, as confirmed by pharmacological blockers. Second, monophasic epiretinal anodal or subretinal cathodal currents elicit spikes in ganglion cells by hyperpolarization of photoreceptor terminals. These stimuli mimic the photoreceptor response to light increments. Third, the stimulation symmetry between current polarities (anodal/cathodal) and retina-array configuration (epi/sub) is confirmed in an experiment in which stimuli presented at different positions reveal the center-surround organization of the ganglion cell. A simple biophysical model that relies on voltage changes of cell terminals in the transretinal electric field above the stimulation capacitor explains our results. This study provides a comprehensive guide for efficient stimulation of different retinal neuronal classes with low-amplitude capacitive currents.

Reorganization of the innervation of the vas deferens after sympathetic decentralization

1996 ◽  
Vol 271 (6) ◽  
pp. R1481-R1488
Author(s):  
K. Kihara ◽  
H. Kakizaki ◽  
W. C. de Groat
Keyword(s):  
Electrical Stimulation ◽  
Vas Deferens ◽  
Ganglion Cells ◽  
Rat Vas Deferens ◽  
Pelvic Nerve ◽  
Hypogastric Nerve ◽  
Normal Side ◽  
Efferent Pathways ◽  
Stimulation Of

Reorganization of autonomic efferent pathways to the rat vas deferens was noted after chronic (30 days) sympathetic decentralization produced by hypogastric nerve (HGN) transection. In normal rats, electrical stimulation of the HGN elicited an increase in vasal pressure (VP) bilaterally, whereas pelvic nerve (PN) stimulation did not alter VP. However, after unilateral HGN transection, stimulation of the PN on the transected side but not on the normal side increased VP. The decentralized vas exhibited larger VP responses to stimulation of the contralateral HGN in comparison with the normal vas. After bilateral HGN transection, PN-induced VP responses were elicited at lower stimulus intensities than in rats with unilateral transections. PN-induced VP responses were blocked by hexamethonium and prazosin but were not altered by atropine. Distension of the vas lumen occurred after decentralization. PN-induced VP responses were not detectable in extremely distended vas. These data indicate that, after degeneration of sympathetic preganglionic axons, decentralized adrenergic ganglion cells are reinnervated by parasympathetic or sympathetic preganglionic pathways and that the reinnervation influences vasal function.

Vesico-Urethral Electrical Stimulation with Surgically Implanted Devices

1993 ◽  
Vol 60 (1) ◽  
pp. 77-86 ◽  
Author(s):  
C. Simeone ◽  
T. Zanotelli ◽  
S. Cosciani-Cunico
Keyword(s):  
Electrical Stimulation ◽  
Experimental Research ◽  
Surgical Techniques ◽  
Clinical Results ◽  
Portable Devices ◽  
Detrusor Muscle ◽  
Direct Stimulation ◽  
Long Period ◽  
Implanted Devices ◽  
Stimulation Of

Good clinical results may be achieved with electrical stimulation in many fields of medicine. After a long period of experimental research, electrical stimulation has gained an important role in Urology too. Surgically implanted devices have been utilized only in recent years to cure neurogenic bladder, while external electrical stimulation with portable devices for female incontinence is well-defined in literature. Direct stimulation of detrusor muscle and sphincter was abandoned but, nowadays, selective neurostimulation seems to be very effective. In this paper, the most important surgical techniques are reviewed. Even if some of them are no longer used, knowledge of them is probably important to a better understanding of present results and future possibilities.

Optimizing the Electrical Stimulation of Retinal Ganglion Cells

2015 ◽  
Vol 23 (2) ◽  
pp. 169-178 ◽  
Author(s):  
A. E. Hadjinicolaou ◽  
C. O. Savage ◽  
N. V. Apollo ◽  
D. J. Garrett ◽  
S. L. Cloherty ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
Retinal Ganglion Cells ◽  
Ganglion Cells ◽  
Retinal Ganglion ◽  
Stimulation Of

Transcutaneous Electrical Stimulation of the Recurrent Laryngeal Nerve in Monkeys

1987 ◽  
Vol 96 (1) ◽  
pp. 38-42 ◽  
Author(s):  
Ira Sanders ◽  
Jonathan Aviv ◽  
Michael M. Racenstein ◽  
Warren M. Kraus ◽  
Hugh F. Biller
Keyword(s):  
Electrical Stimulation ◽  
Recurrent Laryngeal Nerve ◽  
Vocal Cord ◽  
Laryngeal Nerve ◽  
Transcutaneous Electrical Stimulation ◽  
Direct Stimulation ◽  
Glottic Closure ◽  
Unilateral Stimulation ◽  
Tracheoesophageal Groove ◽  
Stimulation Of

The recurrent laryngeal nerve (RLN) of four anesthetized adult Macaca fascicularis monkeys was stimulated by applying current with blunt electrodes placed unilaterally and bilaterally on the intact neck skin along the tracheoesophageal groove. The stimulus consisted of 2.5- to 4.0-mA cathodal pulses, each of 1-ms duration, beginning at a frequency of 10 Hz and increasing by 10-Hz increments to 100 Hz. Unilateral stimulation from 10 to 30 Hz resulted in a graded vocal cord abduction, with the maximal glottic aperture occurring at 30 Hz. Stimulation above 30 Hz produced a graded cord adduction, with nearly complete glottic closure at 100 Hz; bilateral stimulation yielded similar results, with total glottic closure at 100 Hz. Confirmation of the RLN as mediator of this frequency-dependent cord motion was achieved by surgically isolating it and attaining identical results with direct stimulation. No cardiopulmonary alterations were observed in any trial. Transcutaneous electrical stimulation of the RLN seems to be a relatively safe, reliable, and noninvasive method of controlling vocal cord position and thereby the glottic airway in monkeys.

scholarly journals Differential optogenetic excitation of the auditory midbrain in freely moving behaving mice

2021 ◽  
Author(s):  
Meike M. Rogalla ◽  
Adina Seibert ◽  
K Jannis Hildebrandt
Keyword(s):  
Electrical Stimulation ◽  
Surrounding Medium ◽  
Frequency Discrimination ◽  
Auditory Midbrain ◽  
Partial Restoration ◽  
Neuronal Ensembles ◽  
Sensory Pathway ◽  
Freely Moving ◽  
Differential Excitation ◽  
Stimulation Of

AbstractIn patients with severe sensory impairment due to compromised peripheral function, partial restoration can be achieved by implantation of sensory prostheses for the electrical stimulation of the central nervous system. However, these state of the art approaches suffer from the drawback of limited spectral resolution. Electrical field spread depends on the impedance of the surrounding medium, impeding spatially focused electrical stimulation in neural tissue. To overcome these technical limitations, optogenetic excitation could be applied in such prostheses to achieve enhanced resolution through precise and differential stimulation of nearby neuronal ensembles within the central sensory pathway. Previous experiments have provided a first proof for behavioral detectability of optogenetic excitation in the rodent auditory system. However, little is known about the generation of complex and behaviorally relevant sensory patterns involving differential excitation. In this study, we developed an optogenetic implant to excite two spatially separated points along the tonotopy of the murine central inferior colliculus (ICc). Using a newly-devised reward-based operant Go/No-Go paradigm for the evaluation of optogenetic excitation of the auditory midbrain in freely moving, behaving mice, we demonstrate that differential optogenetic excitation of a sub-cortical sensory pathway is possible and efficient. Here we demonstrate how animals which were previously trained in a frequency discrimination paradigm a) rapidly generalize between sound and optogenetic excitation, b) generally detect optogenetic excitation at two different neuronal ensembles, and c) discriminate between them. Our results demonstrate for the first time that optogenetic excitation at different points of the ICc tonotopy elicits a stable response behavior over time periods of several months. With this study, we provide the first proof of principle for sub-cortical differential stimulation of sensory systems using complex artificial cues in freely moving animals.

Evidence for a synaptically mediated decrease in conductance in a crustacean myocardium

1976 ◽  
Vol 65 (1) ◽  
pp. 117-129
Author(s):  
J. C. Delaleu
Keyword(s):  
Electrical Stimulation ◽  
Heart Muscle ◽  
Membrane Resistance ◽  
Inward Current ◽  
Partial Restoration ◽  
Inhibitory Processes ◽  
Myocardial Membrane ◽  
Composite Nature ◽  
Inhibitory Regulation ◽  
Stimulation Of

1. In the neurogenic heart of the isopod Porcellio dilatatus, electrical stimulation of the cardio-regulatory nerves at rates greater than 20–25 pulses/s elicited inhibitory junctional potentials (IJPs) in the myocardium. Its cessation was followed by a long lasting hyperpolarization of myocardial membrane (post-stimulus hyperpolarization = PSH). 2. During the PSH the membrane resistance of the heart muscle increased. The PSH was enhanced by myocardium hyperpolarization, decreased by depolarization and reversed around −50 mV. 3. Picrotoxin inhibited the summated IJPs elicited by the stimulation and thus caused the membrane to maximally hyperpolarize during inhibitory train, thus suggesting a composite nature of the inhibitory processes. 4. The PSH was reversibly reduced in K+-free saline or in ouabain containing saline but partial restoration was obtained by injection of inward current to the myocardium. 5. The PSH was abolished in lithium saline and reduced in Na+-deficient (choline) solution. Cl-deficient solution that markedly affected the summated IJPs shortly after its introduction did not affect the PSH. 6. It is proposed that the PSH results from a decrease in conductance, presumably to both Na+ and K+. The implication of such a mechanism as a component of the inhibitory regulation of this crustacean heart is discussed.

Sign in / Sign up

Export Citation Format

Share Document