Anisotropic receptive field structure of cat horizontal cells

Recent experimental studies of hetero-synaptic interactions in various systems have shown the role of signaling in the plasticity, challenging the conventional understanding of Hebb's rule. It has also been found that activity plays a major role in plasticity, with neurotrophins acting as molecular signals translating activity into structural changes. Furthermore, role of synaptic efficacy in biasing the outcome of competition has also been revealed recently. Motivated by these experimental findings we present a model for the development of simple cell receptive field structure based on the competitive hetero-synaptic interactions for neurotrophins combined with cooperative hetero-synaptic interactions in the spatial domain. We find that with proper balance in competition and cooperation, the inputs from two populations (ON/OFF) of LGN cells segregate starting from the homogeneous state. We obtain segregated ON and OFF regions in simple cell receptive field. Our modeling study supports the experimental findings, suggesting the role of synaptic efficacy and the role of spatial signaling. We find that using this model we obtain simple cell RF, even for positively correlated activity of ON/OFF cells. We also compare different mechanism of finding the response of cortical cell and study their possible role in the sharpening of orientation selectivity. We find that degree of selectivity improvement in individual cells varies from case to case depending upon the structure of RF field and type of sharpening mechanism.

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Receptive field of the retinal bipolar cell: a pharmacological study in the tiger salamander

Journal of Neurophysiology ◽

10.1152/jn.1996.76.3.2005 ◽

1996 ◽

Vol 76 (3) ◽

pp. 2005-2019 ◽

Cited By ~ 42

Author(s):

W. A. Hare ◽

W. G. Owen

Keyword(s):

Receptive Field ◽

Gaba Receptors ◽

Bipolar Cell ◽

Horizontal Cell ◽

Pharmacological Study ◽

Bipolar Cells ◽

Horizontal Cells ◽

Gaba Uptake ◽

Gamma Aminobutyric Acid ◽

Gabaergic Synapse

1. It is widely believed that signals contributing to the receptive field surrounds of retinal bipolar cells pass from horizontal cells to bipolar cells via GABAergic synapses. To test this notion, we applied gamma-aminobutyric acid (GABA) agonists and antagonists to isolated, perfused retinas of the salamander Ambystoma tigrinum while recording intracellularly from bipolar cells, horizontal cells, and photoreceptors. 2. As we previously reported, administration of the GABA analogue D-aminovaleric acid in concert with picrotoxin did not block horizontal cell responses or the center responses of bipolar cells but blocked the surround responses of both on-center and off-center bipolar cells. 3. Surround responses were not blocked by the GABA, antagonists picrotoxin or bicuculline, the GABAB agonist baclofen or the GABAB antagonist phaclofen, and the GABAC antagonists picrotoxin or cis-4-aminocrotonic acid. Combinations of these drugs were similarly ineffective. 4. GABA itself activated a powerful GABA uptake mechanism in horizontal cells for which nipecotic acid is a competitive agonist. It also activated, both in horizontal cells and bipolar cells, large GABAA conductances that shunted light responses but that could be blocked by picrotoxin or bicuculline. 5. GABA, administered together with picrotoxin to block the shunting effect of GABAA activation, did not eliminate bipolar cell surround responses at concentrations sufficient to saturate the known types of GABA receptors. 6. Surround responses were not blocked by glycine or its antagonist strychnine, or by combinations of drugs designed to eliminate GABAergic and glycinergic pathways simultaneously. 7. Although we cannot fully discount the involvement of a novel GABAergic synapse, the simplest explanation of our findings is that the primary pathway mediating the bipolar cell's surround is neither GABAergic nor glycinergic.

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Parallel ON and OFF Cone Bipolar Inputs Establish Spatially Coextensive Receptive Field Structure of Blue-Yellow Ganglion Cells in Primate Retina

Journal of Neuroscience ◽

10.1523/jneurosci.1218-09.2009 ◽

2009 ◽

Vol 29 (26) ◽

pp. 8372-8387 ◽

Cited By ~ 72

Author(s):

J. D. Crook ◽

C. M. Davenport ◽

B. B. Peterson ◽

O. S. Packer ◽

P. B. Detwiler ◽

...

Keyword(s):

Receptive Field ◽

Ganglion Cells ◽

Field Structure

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Receptive-field structure in cat striate cortex.

Journal of Neurophysiology ◽

10.1152/jn.1981.46.2.260 ◽

1981 ◽

Vol 46 (2) ◽

pp. 260-276 ◽

Cited By ~ 108

Author(s):

L A Palmer ◽

T L Davis

Keyword(s):

Receptive Field ◽

Striate Cortex ◽

Field Structure ◽

Cat Striate Cortex

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Attention operates uniformly throughout the classical receptive field and the surround

eLife ◽

10.7554/elife.17256 ◽

2016 ◽

Vol 5 ◽

Cited By ~ 8

Author(s):

Bram-Ernst Verhoef ◽

John HR Maunsell

Keyword(s):

Receptive Field ◽

Cortical Neurons ◽

Receptive Fields ◽

Spatial Summation ◽

Field Structure ◽

Neuronal Responses ◽

Large Variability ◽

Area V4 ◽

Classical Receptive Field ◽

Spatially Varying

Shifting attention among visual stimuli at different locations modulates neuronal responses in heterogeneous ways, depending on where those stimuli lie within the receptive fields of neurons. Yet how attention interacts with the receptive-field structure of cortical neurons remains unclear. We measured neuronal responses in area V4 while monkeys shifted their attention among stimuli placed in different locations within and around neuronal receptive fields. We found that attention interacts uniformly with the spatially-varying excitation and suppression associated with the receptive field. This interaction explained the large variability in attention modulation across neurons, and a non-additive relationship among stimulus selectivity, stimulus-induced suppression and attention modulation that has not been previously described. A spatially-tuned normalization model precisely accounted for all observed attention modulations and for the spatial summation properties of neurons. These results provide a unified account of spatial summation and attention-related modulation across both the classical receptive field and the surround.

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