Hostname: page-component-78c5997874-m6dg7 Total loading time: 0 Render date: 2024-11-04T05:14:46.821Z Has data issue: false hasContentIssue false

Binocular convergence of excitatory and inhibitory synaptic pathways onto neurons of cat visual cortex

Published online by Cambridge University Press:  02 June 2009

David Ferster
Affiliation:
Department of Neurobiology and Physiology, Northwestern University, Evanston, Illinois

Abstract

When a cortical neuron receives synaptic input from both eyes, do the synaptic pathways that mediate the input from each eye match? In this study, inputs from the two eyes were compared by measuring the latencies of EPSPs and IPSPs evoked by electrical stimulation of the two optic nerves. For binocular neurons, these latencies invariably matched closely, indicating that the pathways from the two eyes contain the same number of synapses; monosynaptic input from lamina A of the lateral geniculate nucleus (LGN) is always matched by monosynaptic input from lamina A1. Conversely, polysynaptic input from one eye, either excitatory or inhibitory, is invariably accompanied by similar input from the other eye. In addition, the match between the two eyes in latency indicates that for each eye a synaptic potential is mediated by the same type of afferent, either X or Y.

Judging from intracellular recording, 75% of the neurons studied were binocular, that is, EPSPs could be evoked from either eye. In the remaining 25%, EPSPs could be evoked from only one eye, in agreement with extracellular receptive field studies in which 30% of cortical neurons are monocular.

Type
Short Communication
Copyright
Copyright © Cambridge University Press 1990

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bishop, P.O. & McLeod, J.G. (1954). Nature of potentials associated with synaptic transmission in lateral geniculate nucleus of cat. Journal of Neurophysiology 17, 387414.CrossRefGoogle Scholar
Carlson, M., Hubel, D.H. & Wiesel, T.N. (1986). Effects of monocular exposure to oriented lines on monkey striate cortex. Developmental Brain Research 25, 7181.CrossRefGoogle Scholar
Cleland, B.G., Dubin, M.W. & Levick, W.R. (1971). Sustained and transient neurones in the cat's retina and lateral geniculate nucleus. Journal of Physiology (London). 217, 473496.CrossRefGoogle ScholarPubMed
Ferster, D. (1990). X- and Y-mediated synaptic potentials in neurons of areas 17 and 18 of cat visual cortex. Visual Neuroscience 4, 115133.CrossRefGoogle ScholarPubMed
Ferster, D. & Lindström, S. (1983). An intracellular analysis of geniculocortical connectivity in area 17 of the cat. Journal of Physiology (London). 342, 181215.CrossRefGoogle ScholarPubMed
Guillery, R.W. & Stelzner, D.J. (1970). The differential effects of unilateral lid closure upon the monocular and binocular segments of the dorsal lateral geniculate nucleus in the cat. Journal of Comparative Neurology 139, 413422.CrossRefGoogle ScholarPubMed
Hubel, D.H. & Wiesel, T.N. (1962). Receptive fields, binocular interaction and functional architecture in the cat's visual cortex. Journal of Physiology (London). 160, 106154.CrossRefGoogle ScholarPubMed
Ito, M., Sanides, D. & Creutzfeldt, O.D. (1977). A study of binocular convergence in visual cortex neurons. Experimental Brain Research 28, 2135.Google ScholarPubMed
LeVay, S., Hubel, D.H. & Wiesel, T.N. (1980). The development of ocular dominance columns in normal and visually deprived monkeys. Journal of Comparative Neurology 191, 151.CrossRefGoogle ScholarPubMed
Mitzdorf, U. & Singer, W. (1977). Laminar segregation of afferents to lateral geniculate nucleus of the cat: An analysis of current source density. Journal of Neurophysiology 40, 12271244.CrossRefGoogle Scholar
Shatz, C.J. & Stryker, M.P. (1978). Ocular dominance in layer IV of the cat's visual cortex and the effects of monocular deprivation. 281, 267283.Google Scholar
Stryker, M.P. & Harris, W.A. (1986). Binocular impulse blockade prevents the formation of ocular dominance columns in cat visual cortex. Journal of Neuroscience 6, 21172133.CrossRefGoogle ScholarPubMed
Tsumoto, T. (1978). Inhibitory and excitatory binocular convergence to visual cortical neurons of the cat. Brain Research 159, 8597.CrossRefGoogle ScholarPubMed
Wiesel, T.N. & Hubel, D.H. (1963). Single cell responses in striate cortex of kittens deprived of vision in one eye. Journal of Neurophysiology 26, 10031017.CrossRefGoogle ScholarPubMed
Wilson, P.D., Rowe, M.H. & Stone, J. (1976). Properties of relay cells in the cat's lateral geniculate nucleus: A comparison of W-cells with X- and Y-cells. Journal of Neurophysiology 39, 11931209.CrossRefGoogle ScholarPubMed