scholarly journals Feedback from V1 and inhibition from beyond the classical receptive field modulates the responses of neurons in the primate lateral geniculate nucleus

2002 ◽  
Vol 19 (5) ◽  
pp. 583-592 ◽  
Author(s):  
BEN S. WEBB ◽  
CHRIS J. TINSLEY ◽  
NICK E. BARRACLOUGH ◽  
ALEXANDER EASTON ◽  
AMANDA PARKER ◽  
...  
Keyword(s):  
Receptive Field ◽  
Firing Rate ◽  
Lateral Geniculate Nucleus ◽  
Visual Information ◽  
Striate Cortex ◽  
Temporal Frequency ◽  
Optimal Size ◽  
Marmoset Monkey ◽  
Lateral Geniculate ◽  
Classical Receptive Field

It is well established that the responses of neurons in the lateral geniculate nucleus (LGN) can be modulated by feedback from visual cortex, but it is still unclear how cortico-geniculate afferents regulate the flow of visual information to the cortex in the primate. Here we report the effects, on the gain of LGN neurons, of differentially stimulating the extraclassical receptive field, with feedback from the striate cortex intact or inactivated in the marmoset monkey, Callithrix jacchus. A horizontally oriented grating of optimal size, spatial frequency, and temporal frequency was presented to the classical receptive field. The grating varied in contrast (range: 0–1) from trial to trial, and was presented alone, or surrounded by a grating of the same or orthogonal orientation, contained within either a larger annular field, or flanks oriented either horizontally or vertically. V1 was ablated to inactivate cortico-geniculate feedback. The maximum firing rate of LGN neurons was greater with V1 intact, but was reduced by visually stimulating beyond the classical receptive field. Large horizontal or vertical annular gratings were most effective in reducing the maximum firing rate of LGN neurons. Magnocellular neurons were most susceptible to this inhibition from beyond the classical receptive field. Extraclassical inhibition was less effective with V1 ablated. We conclude that inhibition from beyond the classical receptive field reduces the excitatory influence of V1 in the LGN. The net balance between cortico-geniculate excitation and inhibition from beyond the classical receptive field is one mechanism by which signals relayed from the retina to V1 are controlled.

Spatial Distribution of Suppressive Signals Outside the Classical Receptive Field in Lateral Geniculate Nucleus

2005 ◽  
Vol 94 (3) ◽  
pp. 1789-1797 ◽  
Author(s):  
Ben S. Webb ◽  
Christopher J. Tinsley ◽  
Christopher J. Vincent ◽  
Andrew M. Derrington
Keyword(s):  
Spatial Distribution ◽  
Receptive Field ◽  
Lateral Geniculate Nucleus ◽  
Spatial Organization ◽  
Temporal Frequency ◽  
Spatial Summation ◽  
Sinusoidal Grating ◽  
Circular Symmetry ◽  
Lateral Geniculate ◽  
Classical Receptive Field

A suppressive surround modulates the responsiveness of cells in the lateral geniculate nucleus (LGN), but we know nothing of its spatial structure or the way in which it combines signals arising from different locations. It is generally assumed that suppressive signals are either uniformly distributed or balanced in opposing regions outside the receptive field. Here, we examine the spatial distribution and summation of suppressive signals outside the receptive field in extracellular recordings from 46 LGN cells in anesthetized marmosets. The receptive field of each cell was stimulated with a drifting sinusoidal grating of the preferred size and spatial and temporal frequency; we probed different positions in the suppressive surround with either a large half-annular grating or a small circular grating patch of the preferred spatial and temporal frequency. In many of the cells with a strong suppressive surround (29/46), the spatial distribution of suppression showed clear deviation from circular symmetry. In the majority of these of cells, suppressive signals were spatially asymmetrical or balanced in opposing areas outside the receptive field. A suppressive area was larger than the classical receptive field itself and spatial summation within and between these areas was nonlinear. There was no bias for suppression to arise from foveal or nasal retina where cone density is higher and no other sign of a systematic spatial organization to the suppressive surround. We conclude that nonclassical suppressive signals in LGN deviate from circular symmetry and are nonlinearly combined.

Striate cortex increases contrast gain of macaque LGN neurons

2000 ◽  
Vol 17 (4) ◽  
pp. 485-494 ◽  
Author(s):  
ANDRZEJ W. PRZYBYSZEWSKI ◽  
JAMES P. GASKA ◽  
WARREN FOOTE ◽  
DANIEL A. POLLEN
Keyword(s):  
Receptive Field ◽  
Lateral Geniculate Nucleus ◽  
Functional Significance ◽  
Striate Cortex ◽  
Experimental Basis ◽  
Contrast Gain ◽  
Classical Receptive Field ◽  
Wide Range ◽  
Universal Feature ◽  
Parvocellular Neurons

Recurrent projections comprise a universal feature of cerebral organization. Here, we show that the corticofugal projections from the striate cortex (V1) to the lateral geniculate nucleus (LGN) robustly and multiplicatively enhance the responses of parvocellular neurons, stimulated by gratings restricted to the classical receptive field and modulated in luminance, by over two-fold in a contrast-independent manner at all but the lowest contrasts. In the equiluminant plane, wherein stimuli are modulated in chromaticity with luminance held constant, such enhancement is strongly contrast dependent. These projections also robustly enhance the responses of magnocellular neurons but contrast independently only at high contrasts. Thus, these results have broad functional significance at both network and neuronal levels by providing the experimental basis and quantitative constraints for a wide range of models on recurrent projections and the control of contrast gain.

Cortical feedback increases visual information transmitted by monkey parvocellular lateral geniculate nucleus neurons

1994 ◽  
Vol 11 (3) ◽  
pp. 601-617 ◽  
Author(s):  
John W. McClurkin ◽  
Lance M. Optican ◽  
Barry J. Richmond
Keyword(s):  
Lateral Geniculate Nucleus ◽  
Visual Information ◽  
Striate Cortex ◽  
Temporal Distribution ◽  
Information Measure ◽  
Signal Separation ◽  
Transmitted Information ◽  
Related Information ◽  
Lateral Geniculate ◽  
Stimulus Parameters

AbstractWe studied the effect of cooling the striate cortex on parvocellular lateral geniculate nucleus (PLGN) neurons in awake monkeys. Cooling the striate cortex produced both facilitation and inhibition of the responses of all neurons, depending on the stimulus presented. Cooling the striate cortex also altered the temporal distribution of spikes in the responses of PLGN neurons. Shannon's information measure revealed that cooling the striate cortex reduced the average stimulus-related information transmitted by all PLGN neurons. The reduction in transmitted information was associated with both facilitation and inhibition of the response. Cooling the striate cortex reduced the amount of information transmitted about all of the stimulus parameters tested: pattern, luminance, spatial contrast, and sequential contrast. The effect of cooling was nearly the same for codes based on the number of spikes in the response as for codes based on their temporal distribution. The reduction in transmitted information occurred because the differences among the responses to different stimuli (signal separation) were reduced, not because the variability of the responses to individual stimuli (noise) was increased. We conclude that one function of corticogeniculate feedback is to improve the ability of PLGN neurons to discriminate among stimuli by enhancing the differences among their responses.

Visual signal processing in the macaque lateral geniculate nucleus

2012 ◽  
Vol 29 (2) ◽  
pp. 105-117 ◽  
Author(s):  
THORSTEIN SEIM ◽  
ARNE VALBERG ◽  
BARRY B. LEE
Keyword(s):  
Receptive Field ◽  
Lateral Geniculate Nucleus ◽  
Visual Information ◽  
Field Size ◽  
Visual Signal ◽  
Test Field ◽  
Retinal Ganglion ◽  
Relay Cell ◽  
Firing Rates ◽  
Lateral Geniculate

AbstractComparisons of S- or prepotential activity, thought to derive from a retinal ganglion cell afferent, with the activity of relay cells of the lateral geniculate nucleus (LGN) have sometimes implied a loss, or leak, of visual information. The idea of the “leaky” relay cell is reconsidered in the present analysis of prepotential firing and LGN responses of color-opponent cells of the macaque LGN to stimuli varying in size, relative luminance, and spectral distribution. Above a threshold prepotential spike frequency, called the signal transfer threshold (STT), there is a range of more than 2 log units of test field luminance that has a 1:1 relationship between prepotential- and LGN-cell firing rates. Consequently, above this threshold, the LGN cell response can be viewed as an extension of prepotential firing (a “nonleaky relay cell”). The STT level decreased when the size of the stimulus increased beyond the classical receptive field center, indicating that the LGN cell is influenced by factors other than the prepotential input. For opponent ON cells, both the excitatory and the inhibitory response decreased similarly when the test field size increased beyond the center of the receptive field. These findings have consequences for the modeling of LGN cell responses and transmission of visual information, particularly for small fields. For instance, for LGN ON cells, information in the prepotential intensity–response curve for firing rates below the STT is left to be discriminated by OFF cells. Consequently, for a given light adaptation, the STT improves the separation of the response range of retinal ganglion cells into “complementary” ON and OFF pathways.

Organization of Binocular Pathways: Modeling and Data Related to Rivalry

1991 ◽  
Vol 3 (1) ◽  
pp. 44-53 ◽  
Author(s):  
Sidney R. Lehky ◽  
Randolph Blake
Keyword(s):  
Lateral Geniculate Nucleus ◽  
Binocular Rivalry ◽  
Striate Cortex ◽  
Reciprocal Inhibition ◽  
Lateral Geniculate ◽  
Layer 4 ◽  
Inhibitory Coupling ◽  
Binocular Matching

It is proposed that inputs to binocular cells are gated by reciprocal inhibition between neurons located either in the lateral geniculate nucleus or in layer 4 of striate cortex. The strength of inhibitory coupling in the gating circuitry is modulated by layer 6 neurons, which are the outputs of binocular matching circuitry. If binocular inputs are matched, the inhibition is modulated to be weak, leading to fused vision, whereas if the binocular inputs are unmatched, inhibition is modulated to be strong, leading to rivalrous oscillations. These proposals are buttressed by psychophysical experiments measuring the strength of adaptational aftereffects following exposure to an adapting stimulus visible only intermittently during binocular rivalry.

The multifaceted role of inhibitory interneurons in the dorsal lateral geniculate nucleus

2017 ◽  
Vol 34 ◽  
Author(s):  
CHARLES L. COX ◽  
JOSEPH A. BEATTY
Keyword(s):  
Glutamate Receptors ◽  
Lateral Geniculate Nucleus ◽  
Visual Information ◽  
Metabotropic Glutamate Receptors ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Metabotropic Glutamate ◽  
Lateral Geniculate ◽  
Presynaptic Dendrites ◽  
Dorsal Lateral Geniculate ◽  
Stimulation Of

AbstractIntrinsic interneurons within the dorsal lateral geniculate nucleus (dLGN) provide a feed-forward inhibitory pathway for afferent visual information originating from the retina. These interneurons are unique because in addition to traditional axodendritic output onto thalamocortical neurons, these interneurons have presynaptic dendrites that form dendrodendritic synapses onto thalamocortical neurons as well. These presynaptic dendrites, termed F2 terminals, are tightly coupled to the retinogeniculate afferents that synapse onto thalamocortical relay neurons. Retinogeniculate stimulation of F2 terminals can occur through the activation of ionotropic and/or metabotropic glutamate receptors. The stimulation of ionotropic glutamate receptors can occur with single stimuli and produces a short-lasting inhibition of the thalamocortical neuron. By contrast, activation of metabotropic glutamate receptors requires tetanic activation and results in longer-lasting inhibition in the thalamocortical neuron. The F2 terminals are predominantly localized to the distal dendrites of interneurons, and the excitation and output of F2 terminals can occur independent of somatic activity within the interneuron thereby allowing these F2 terminals to serve as independent processors, giving rise to focal inhibition. By contrast, strong transient depolarizations at the soma can initiate a backpropagating calcium-mediated potential that invades the dendritic arbor activating F2 terminals and leading to a global form of inhibition. These distinct types of output, focal versus global, could play an important role in the temporal and spatial roles of inhibition that in turn impacts thalamocortical information processing.

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