Biomaterial Database

Influence of eye movements on geniculo-striate excitability in the cat. 1973

W R Adey, and H Noda

1. The excitability of the geniculo-striate pathway during a saccadic eye movement was studied in alert cats with chronically implanted electrodes. Excitability was assessed by the amplitude of post-synaptic components of field responses in both lateral geniculate nucleus and visual cortex to electrical stimulation of the optic chiasm. Modifications in amplitude were evaluated during the period following eye movements, by triggering a stimulator from potential shifts in the electrooculograms and altering delays in the stimulus pulse.2. The post-synaptic component of the geniculate response was markedly depressed for about 150 msec, reaching a trough at approximately 100 msec after the initiation of an eye movement. This effect was dependent on the visual environment and was not observed in complete darkness. A similar depression occurred when the visual field was abruptly moved by retinal impulses generated by a quick displacement of the image of the visual world associated with an eye movement. The depression reflected a reduction of cellular discharge to the orthodromic volley and hence a suppression of the transmission of visual information through the lateral geniculate nucleus. This may be a mechanism for saccadic suppression.3. The post-synaptic components of the cortical response were enhanced for about 200 msec, reaching a peak at approximately 150 msec after the initiation of an eye movement. Although this facilitation occurred also in complete darkness, it did not occur when the visual field was abruptly shifted while the eyes were stationary. The fact that it occurred with eye movements and exclusively in the post-synaptic components suggests that it was caused by signals from a system closely related to eye movements. This may be a manifestation of the corollary mechanism.

UI	MeSH Term	Description	Entries
D009039	Motion Perception	The real or apparent movement of objects through the visual field.	Movement Perception,Perception, Motion,Perception, Movement
D009897	Optic Chiasm	The X-shaped structure formed by the meeting of the two optic nerves. At the optic chiasm the fibers from the medial part of each retina cross to project to the other side of the brain while the lateral retinal fibers continue on the same side. As a result each half of the brain receives information about the contralateral visual field from both eyes.	Chiasma Opticum,Optic Chiasma,Optic Decussation,Chiasm, Optic,Chiasma Opticums,Chiasma, Optic,Chiasmas, Optic,Chiasms, Optic,Decussation, Optic,Decussations, Optic,Optic Chiasmas,Optic Chiasms,Optic Decussations,Opticum, Chiasma,Opticums, Chiasma
D002415	Cats	The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)	Felis catus,Felis domesticus,Domestic Cats,Felis domestica,Felis sylvestris catus,Cat,Cat, Domestic,Cats, Domestic,Domestic Cat
D003624	Darkness	The absence of light.	Darknesses
D004558	Electric Stimulation	Use of electric potential or currents to elicit biological responses.	Stimulation, Electric,Electrical Stimulation,Electric Stimulations,Electrical Stimulations,Stimulation, Electrical,Stimulations, Electric,Stimulations, Electrical
D004585	Electrooculography	Recording of the average amplitude of the resting potential arising between the cornea and the retina in light and dark adaptation as the eyes turn a standard distance to the right and the left. The increase in potential with light adaptation is used to evaluate the condition of the retinal pigment epithelium.	EOG,Electrooculograms,Electrooculogram
D005133	Eye Movements	Voluntary or reflex-controlled movements of the eye.	Eye Movement,Movement, Eye,Movements, Eye
D005829	Geniculate Bodies	Part of the DIENCEPHALON inferior to the caudal end of the dorsal THALAMUS. Includes the lateral geniculate body which relays visual impulses from the OPTIC TRACT to the calcarine cortex, and the medial geniculate body which relays auditory impulses from the lateral lemniscus to the AUDITORY CORTEX.	Lateral Geniculate Body,Medial Geniculate Body,Metathalamus,Corpus Geniculatum Mediale,Geniculate Nucleus,Lateral Geniculate Nucleus,Medial Geniculate Complex,Medial Geniculate Nucleus,Nucleus Geniculatus Lateralis Dorsalis,Nucleus Geniculatus Lateralis Pars Dorsalis,Bodies, Geniculate,Complex, Medial Geniculate,Complices, Medial Geniculate,Corpus Geniculatum Mediales,Geniculate Bodies, Lateral,Geniculate Bodies, Medial,Geniculate Body,Geniculate Body, Lateral,Geniculate Body, Medial,Geniculate Complex, Medial,Geniculate Complices, Medial,Geniculate Nucleus, Lateral,Geniculate Nucleus, Medial,Geniculatum Mediale, Corpus,Geniculatum Mediales, Corpus,Lateral Geniculate Bodies,Medial Geniculate Bodies,Medial Geniculate Complices,Mediale, Corpus Geniculatum,Mediales, Corpus Geniculatum,Nucleus, Geniculate,Nucleus, Lateral Geniculate,Nucleus, Medial Geniculate
D000200	Action Potentials	Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.	Spike Potentials,Nerve Impulses,Action Potential,Impulse, Nerve,Impulses, Nerve,Nerve Impulse,Potential, Action,Potential, Spike,Potentials, Action,Potentials, Spike,Spike Potential
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia