Visual cortex contribution to the organization of eye movements produced by local electrical stimulation of the cat lateral geniculate body

1987 ◽  
Vol 19 (2) ◽  
pp. 126-130
Author(s):  
V. Ya. Svetlova ◽  
N. F. Podvigin ◽  
F. N. Makarov ◽  
K. P. Fedorova ◽  
E. V. Evpyat'eva
Keyword(s):  
Electrical Stimulation ◽  
Visual Cortex ◽  
Eye Movements ◽  
Lateral Geniculate Body ◽  
Lateral Geniculate ◽  
Stimulation Of

Organization of visual inputs to interneurons of lateral geniculate nucleus of the cat

1977 ◽  
Vol 40 (2) ◽  
pp. 410-427 ◽  
Author(s):  
M. W. Dubin ◽  
B. G. Cleland
Keyword(s):  
Electrical Stimulation ◽  
Visual Cortex ◽  
Lateral Geniculate Nucleus ◽  
Cell Activation ◽  
Synaptic Delay ◽  
Relay Cell ◽  
Inhibitory System ◽  
Spike Response ◽  
Lateral Geniculate ◽  
Stimulation Of

1. Two groups of interneurons that are involved in the organization of the lateral geniculate nucleus (LGN) are described. The cell bodies of one group lie within the LGN; these units are referred to as intrageniculate. The cell bodies of the other group are found immediately above the LGN at its border with the perigeniculate nucleus; these units are referred to as perigeniculate. 2. Intrageniculate interneurons have center-surround receptive fields that resemble those of relay (principal) cells. They can be subdivided into brisk or sluggish and sustained or transient categories. They are stimulated transsynaptically from the visual cortex and have a characteristic variation in the latency of their spike response to such stimulation both at threshold and for suprathreshold stimuli. The pathway for this stimulation appears to be via cortical efferents to the LGN. Intrageniculate interneurons receive direct, monosynaptic retinal inputs, as determined by recording simultaneously from such interneurons and from the ganglion cells which provide excitatory input to them. Similar to relay cells, they are shown to have one or two major ganglion cell inputs. 3. Perigeniculate interneurons are generally binocularly innervated and give on-off responses to small spot stimuli throughout their receptive field. They respond well to rapid movement of large targets. They respond to electrical stimulation of the retina with a spike latency that falls between that of brisk transient and brisk sustained relay cells. This latency is one synaptic delay longer than that of brisk transient relay cell activation and suggests that they are excited by axon collaterals of these relay cells. Electrical stimulation of the visual cortex is also consistent with this model; the latency of the response of perigeniculate interneurons is approximately one synaptic delay longer than the latency of the response of brisk transient relay cells. 4. The interneuronal pathways described are consistent with proposed circuits that subserve the generation of IPSPs that arise in response to optic nerve and visual cortical stimulation. We now show that such inhibition has feed-forward (intrageniculate) and feed-back (perigeniculate) components that are mediated by two different classes of geniculate interneurons. It is suggested that the intrageniculate interneurons are involved in precise, spatially organized inhibition and that the perigeniculate interneurons are part of a more general, diffuse inhibitory system that modulates LGN excitability.

Changes of visual pattern discrimination in adult cats after removal of an aspecific area of cerebral cortex

1961 ◽  
Vol 200 (6) ◽  
pp. 1215-1218 ◽  
Author(s):  
Torquato Gualtierotti
Keyword(s):  
Cerebral Cortex ◽  
Visual Cortex ◽  
Pattern Discrimination ◽  
Lateral Geniculate Body ◽  
Visual Pattern ◽  
Lateral Geniculate ◽  
Sensory Motor ◽  
Adult Cats ◽  
Stimulation Of ◽  
Visual Pattern Discrimination

In the curarized cat, a well-defined, aspecific trigger area (TA) of the cortex, situated in front of the visual cortex caudally to the crux, originated a widespread, 10/sec afterdischarge following stimulation of the lateral geniculate body of the same side. Removal of the TA significantly impaired the visual pattern discrimination of previously trained adult cats, increasing their time of response. Untrained cats were not susceptible to training when the TA had been destroyed on both sides. Removal of an equivalent visual area did not alter visual pattern discrimination. The stimulation of the lateral geniculate body of the same side did not elicit the 10/sec afterdischarge if the TA had been completely destroyed. It is concluded that the TA might be concerned with higher sensory-motor integrative activity.

Properties of ganglion cells with atypical receptive-field organization in retina of macaques

1978 ◽  
Vol 41 (6) ◽  
pp. 1435-1449 ◽  
Author(s):  
F. M. de Monasterio
Keyword(s):  
Electrical Stimulation ◽  
Superior Colliculus ◽  
Ganglion Cells ◽  
Receptive Fields ◽  
Optic Tract ◽  
Spatial Summation ◽  
Lateral Geniculate Body ◽  
Central Retina ◽  
Lateral Geniculate ◽  
Stimulation Of

1. About 10% of a sample of 436 cells recorded in the retina of macaques had receptive fields lacking a center-surround organization. These cells had a diffuse extrafoveal distribution, they were less frequently found in the foveal region, and their conduction latencies overlapped with those of cells (types I, III, and IV) having a center-surround organization. Three groups were distinguished. 2. Type II cells had spectrally opponent responses mediated by mechanisms having similar or identical distributions and response latency; these cells did not respond to white light. They predominated in the central retina, they usually received input from all three types of cone, they had a linear spatial summation of incomming photo-receptor signals, they lacked rod input, they had conduction latencies that were intermediate between those of the other two groups, and they could be antidromically activated by electrical stimulation of the lateral geniculate body but not of the superior colliculus. 3. Type V cells were neurons whose common characteristic was the presence of on-off responses to both small and large stimuli. One subgroup had either excitatory or inhibitory on-off responses and a silent inhibitory surround that tended to suppress cell responses and maintained activity. They were observed throughout the central retina, including the fovea; they received input from green- and red-sensitive cones, but not from blue-sensitive cones; they had a non-linear spatial summation; they had comparatively long conduction latencies; and they could be antidromically activated by electrical stimulation of either the lateral geniculate body or superior colliculus. Another subgroup lacked spontaneous activity and any type of surround. They were encountered at a retinal depth more sclerad than that of other neurons and could not be antidromically driven from the optic tract or more central structures; these cells also lacked input from blue-sensitive cones and had a nonlinear spatial summation. 4. Type VI cells were predominantly inhibited by moving stinuli in any direction of motion and failed to respond to stationary flashing stimuli; they appeared to predominate toward the perifovea and had comparatively short conduction latencies.

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