INTRARETINAL RESPONSES OF THE CYNAMOLGUS MONKEY TO ELECTRICAL STIMULATION OF THE OPTIC NERVE AND RETINA

1964 ◽  
Vol 27 (4) ◽  
pp. 682-705 ◽  
Author(s):  
T. E. Ogden ◽  
K. T. Brown
Keyword(s):  
Electrical Stimulation ◽  
Optic Nerve ◽  
Stimulation Of

Relation of Posttetanic Potentiation to Subnormality of Lateral Geniculate Potentials

1957 ◽  
Vol 188 (2) ◽  
pp. 238-244 ◽  
Author(s):  
Edward V. Evarts ◽  
John R. Hughes
Keyword(s):  
Electrical Stimulation ◽  
Optic Nerve ◽  
Posttetanic Potentiation ◽  
Postsynaptic Response ◽  
Lateral Geniculate ◽  
Decerebrate Cats ◽  
Stimulation Of

The lateral geniculate response to electrical stimulation of the optic nerve was recorded in decerebrate cats and in cats anesthetized with Nembutal. Tetanization of the optic nerve at 500/sec. for 20 seconds in nembutalized cats produced a prolonged second subnormality of the geniculate postsynaptic response. Further tetanization during tetanically-induced second subnormality produced posttetanic potentiation (PTP). The degree of PTP (expressed in percentage of the pretetanic level) of the postsynaptic response following a 20-second tetanus was proportional to the degree of second subnormality present at the time the tetanus was applied. PTP was also found to occur during the subnormality which followed a brief train of optic nerve shocks, and during LSD-induced subnormality. PTP of postsynaptic lateral geniculate potentials occurred only rarely in the absence of some form of intentionally induced subnormality.

Dual actions of isthmic input to tectal neurons in a reptile, Gekko gekko

1999 ◽  
Vol 16 (5) ◽  
pp. 889-893 ◽  
Author(s):  
STEPHEN A. GEORGE ◽  
GANG-YI WU ◽  
WEN-CHANG LI ◽  
SHU-RONG WANG
Keyword(s):  
Electrical Stimulation ◽  
Optic Nerve ◽  
Optic Tectum ◽  
Nucleus Isthmi ◽  
Postsynaptic Potentials ◽  
Tectal Neurons ◽  
Electrical Connections ◽  
Stimulation Of

We analyzed postsynaptic potentials and dye-labeled morphology of tectal neurons responding to electrical stimulation of the optic nerve and of the nucleus isthmi in a reptile, Gekko gekko, in order to compare with previously reported interactions between the optic tectum and the nucleus isthmi in amphibians and birds. The results indicate that isthmic stimulation exerts inhibitory and excitatory actions on tectal cells, similar to dual isthmotectal actions in amphibians. It appears that dual actions of the isthmotectal pathway in amphibians and reptiles are shared by two subdivisions of the nucleus isthmi in birds. The morphology of tectal cells responding to isthmic stimulation is generally similar to that of tectoisthmic projecting neurons, but they differ particularly in that some tectoisthmic cells bear numerous varicosities whereas cells receiving isthmic afferents do not. Thus, it is likely that at least some tectoisthmic cells may not be in the population of tectal cells that can be affected by isthmic stimulation. Forty-four percent of injections resulted in dye-coupled labeling, suggesting extensive electrical connections between tectal cells in reptiles.

Electrical potentials from the eye and optic nerve of Strombus: effects of electrical stimulation of the optic nerve

1977 ◽  
Vol 66 (1) ◽  
pp. 159-171
Author(s):  
H. L. Gillary
Keyword(s):  
Electrical Stimulation ◽  
Optic Nerve ◽  
Synaptic Input ◽  
Oscillatory Potentials ◽  
Photic Stimulation ◽  
Abrupt Decrease ◽  
Electrical Potentials ◽  
Photic Stimulus ◽  
Inhibitory Synaptic Input ◽  
Stimulation Of

1. Photic stimulation of the mature eye of Strombus can evoke in the optic nerve ‘on’ activity in numerous small afferent fibres and repetitive ‘off’ bursts of afferent impulses in a smaller number of larger fibres. 2. Synchronous invasion of the eye by electrically evoked impulses in small optic nerve fibres (apparently the ‘on’ afferents, antidromically activated) can evoke a burst of impulses in the larger ‘off’ fibres which propagate away from the eye. Invasion of the eye via one branch of optic nerve can evoke an answering burst in another branch. 3. Such electrically evoked bursts are similar to light-evoked ‘off’ bursts with respect to their impulse composition, their ability to be inhibited by illumination of the eye, and their susceptibility to MgCl2 anaesthesia. 4. Invasion of the eye by a train of repetitive electrically evoked impulses in the absence of photic stimulation can give rise to repetitive ‘off’ bursts as well as concomitant oscillatory potentials in the eye which are similar to those normally evoked by cessation of a photic stimulus. 5. The electrically evoked ‘off’ bursts appear to be caused by an excitatory rebound following the cessation of inhibitory synaptic input from photoreceptors which can be antidromically activated by electrical stimulation of the optic nerve. 6. The experimental results suggest that the rhythmic discharge of the ‘off’ fibres evoked by the cessation of a photic stimulus is mediated by the abrupt decrease of inhibitory synaptic input from the receptors.

Direct epidural electrical stimulation of the optic nerve: a new method for intraoperative assessment of function

2008 ◽  
Vol 109 (4) ◽  
pp. 647-653 ◽  
Author(s):  
Roman Bošnjak ◽  
Mitja Benedièiè
Keyword(s):  
Electrical Stimulation ◽  
Optic Nerve ◽  
Optic Canal ◽  
Tumor Removal ◽  
Tuberculum Sellae Meningioma ◽  
Close Relationship ◽  
Tuberculum Sellae ◽  
The Impact ◽  
Light Flashes ◽  
Stimulation Of

Intraoperative visual system monitoring of lesions with a close relationship to the optic apparatus by using light flashes reportedly is difficult to perform, and the results are too unreliable to interpret. The authors used direct epidural electrical stimulation of the optic nerve (ON) during surgery instead of light flashes. Four patients were included in this feasibility study. In 3 patients—1 each harboring a planum sphenoidale meningioma, a tuberculum sellae meningioma, and an intraorbital ON sheath meningioma—2 stimulating needle electrodes were placed on each side of the ON just anterior to the optic canal, before unroofing the optic canal and an extradural anterior clinoidectomy. In the fourth patient, who harbored a frontotemporal astrocytoma, stimulation was applied at the exit of the ON from the canal. The electrically induced visual evoked potentials (eVEPs) were recorded from the scalp before, during, and after tumor removal. A typical eVEP consisted of N20 and N40 waves. The amplitude of the N40 wave varied up to 25% prior to tumor removal. In the patient with a symptomatic tuberculum sellae meningioma, the decompressive effect of opening the optic canal and the impact of manipulation during piecemeal tumor removal were detected by the eVEPs. In the patient with an ON sheath meningioma and light sensation, only the N20 wave was observed. Epidural electrical stimulation of the ON is a safe means of providing a stable signal and real-time information on nerve conduction during surgery. It may be a useful adjunct in improving visual outcomes postoperatively. Further clinical studies are necessary.

scholarly journals Erratum to: Axonal regeneration induced by repetitive electrical stimulation of crushed optic nerve in adult rats

2009 ◽  
Vol 53 (5) ◽  
pp. 564-564 ◽  
Author(s):  
Yuichi Tagami ◽  
Takuji Kurimoto ◽  
Tomomitsu Miyoshi ◽  
Takeshi Morimoto ◽  
Hajime Sawai ◽  
...  
Keyword(s):  
Electrical Stimulation ◽  
Optic Nerve ◽  
Axonal Regeneration ◽  
Adult Rats ◽  
Repetitive Electrical Stimulation ◽  
Stimulation Of
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