On the use of isoflurane versus halothane in the study of visual response properties of single cells in the primary visual cortex

ABSTRACTThe normal development of neuronal circuits requires both hard-wired gene expression and experience. Sensory processing, such as vision, is especially sensitive to perturbations in experience. However, the exact contribution of experience to neuronal visual response properties and binocular vision remains unknown. To determine how visual response properties developin vivo, we used single cell resolution two-photon calcium imaging of mouse binocular visual cortex at multiple time-points after eye opening. Few neurons are binocularly responsive immediately after eye opening and respond solely to either the contralateral or ipsilateral eye. Binocular neurons emerge during development, which requires visual experience, and show specific tuning of visual response properties. As binocular neurons emerge, activity between the two eyes becomes more correlated in the neuropil. Since experience-dependent plasticity requires the expression of activity-dependent genes, we determined whether the plasticity geneArcmediates the development of normal visual response properties. Surprisingly, rather than mirroring the effects of visual deprivation, mice that lackArcshow increased numbers of binocular neurons during development. Strikingly, removingArcin adult binocular visual cortex increases the numbers of binocular neurons and recapitulates the developmental phenotype, suggesting cortical circuits that mediate visual processing require ongoing experience-dependent plasticity. Thus, experience is critical for the normal development and maintenance of circuits required to process binocular vision.

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Running reduces firing but improves coding in rodent higher-order visual cortex

10.1101/214007 ◽

2017 ◽

Cited By ~ 7

Author(s):

Amelia J. Christensen ◽

Jonathan W. Pillow

Keyword(s):

Visual Cortex ◽

Primary Visual Cortex ◽

Single Neuron ◽

Higher Order ◽

Visual Responses ◽

Cortical Layers ◽

Response Properties ◽

Stimulus Response ◽

Allen Brain ◽

Visual Areas

Running profoundly alters stimulus-response properties in mouse primary visual cortex (V1), but its effects in higher-order visual cortex remain unknown. Here we systematically investigated how locomotion modulates visual responses across six visual areas and three cortical layers using a massive dataset from the Allen Brain Institute. Although running has been shown to increase firing in V1, we found that it suppressed firing in higher-order visual areas. Despite this reduction in gain, visual responses during running could be decoded more accurately than visual responses during stationary periods. We show that this effect was not attributable to changes in noise correlations, and propose that it instead arises from increased reliability of single neuron responses during running.

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Orientation tuning depends on spatial frequency in mouse visual cortex

10.1101/069997 ◽

2016 ◽

Cited By ~ 1

Author(s):

Inbal Ayzenshtat ◽

Jesse Jackson ◽

Rafael Yuste

Keyword(s):

Visual Cortex ◽

Spatial Frequency ◽

Visual System ◽

Primary Visual Cortex ◽

Receptive Fields ◽

Orientation Selectivity ◽

Natural Scenes ◽

Response Properties ◽

Layer 2 ◽

Mouse Visual Cortex

AbstractThe response properties of neurons to sensory stimuli have been used to identify their receptive fields and functionally map sensory systems. In primary visual cortex, most neurons are selective to a particular orientation and spatial frequency of the visual stimulus. Using two-photon calcium imaging of neuronal populations from the primary visual cortex of mice, we have characterized the response properties of neurons to various orientations and spatial frequencies. Surprisingly, we found that the orientation selectivity of neurons actually depends on the spatial frequency of the stimulus. This dependence can be easily explained if one assumed spatially asymmetric Gabor-type receptive fields. We propose that receptive fields of neurons in layer 2/3 of visual cortex are indeed spatially asymmetric, and that this asymmetry could be used effectively by the visual system to encode natural scenes.Significance StatementIn this manuscript we demonstrate that the orientation selectivity of neurons in primary visual cortex of mouse is highly dependent on the stimulus SF. This dependence is realized quantitatively in a decrease in the selectivity strength of cells in non-optimum SF, and more importantly, it is also evident qualitatively in a shift in the preferred orientation of cells in non-optimum SF. We show that a receptive-field model of a 2D asymmetric Gabor, rather than a symmetric one, can explain this surprising observation. Therefore, we propose that the receptive fields of neurons in layer 2/3 of mouse visual cortex are spatially asymmetric and this asymmetry could be used effectively by the visual system to encode natural scenes.Highlights–Orientation selectivity is dependent on spatial frequency.–Asymmetric Gabor model can explain this dependence.

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Activation of metabotropic glutamate receptors has different effects in different layers of cat visual cortex

Visual Neuroscience ◽

10.1017/s0952523800008786 ◽

1997 ◽

Vol 14 (1) ◽

pp. 83-88 ◽

Cited By ~ 15

Author(s):

Silvia N.M. Reid ◽

Nigel W. Daw

Keyword(s):

Visual Cortex ◽

Dicarboxylic Acid ◽

Glutamate Receptors ◽

Spontaneous Activity ◽

Primary Visual Cortex ◽

Metabotropic Glutamate Receptors ◽

Visual Response ◽

Single Neurons ◽

Metabotropic Glutamate ◽

Cat Visual Cortex

AbstractSingle neurons were recorded in cat primary visual cortex, and the effect of iontophoresis of the metabotropic glutamate agonist 1S,3R-aminocyclopentane-1.3-dicarboxylic acid (ACPD) was observed. In nearly all cases (41/43), ACPD reduced the visual response. In some cases ACPD also reduced spontaneous activity (24/43), and in other cases ACPD increased spontaneous activity (18/43). Increases were generally seen in infragranular layers (V and VI), and decreases in supragranular layers (II and III). The reduction in the visual response was also largest in supragranular layers. We conclude that activation of metabotropic glutamate receptors has both facilitatory and depressive effects in visual cortex, and the effect depends on the layer of the cell recorded.

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Influence of Contrast on Orientation and Temporal Frequency Tuning in Ferret Primary Visual Cortex

Journal of Neurophysiology ◽

10.1152/jn.00943.2003 ◽

2004 ◽

Vol 91 (6) ◽

pp. 2797-2808 ◽

Cited By ~ 83

Author(s):

Henry J. Alitto ◽

W. Martin Usrey

Keyword(s):

Visual Cortex ◽

Primary Visual Cortex ◽

Cortical Neurons ◽

Frequency Tuning ◽

Temporal Frequency ◽

Orientation Tuning ◽

Visual Response ◽

Stimulus Contrast ◽

Tuning Curves ◽

Simple And Complex Cells

Neurons in primary visual cortex are highly sensitive to the contrast, orientation, and temporal frequency of a visual stimulus. These three stimulus properties can be varied independently of one another, raising the question of how they interact to influence neuronal responses. We recorded from individual neurons in ferret primary visual cortex to determine the influence of stimulus contrast on orientation tuning, temporal-frequency tuning, and latency to visual response. Results show that orientation-tuning bandwidth is not affected by contrast level. Thus neurons in ferret visual cortex display contrast-invariant orientation tuning. Stimulus contrast does, however, influence the structure of orientation-tuning curves as measures of circular variance vary inversely with contrast for both simple and complex cells. This change in circular variance depends, in part, on a contrast-dependent change in the ratio of null to preferred orientation responses. Stimulus contrast also has an influence on the temporal-frequency tuning of cortical neurons. Both simple and complex cells display a contrast-dependent rightward shift in their temporal frequency-tuning curves that results in an increase in the highest temporal frequency needed to produce a half-maximum response (TF50). Results show that the degree of the contrast-dependent increase in TF50 is similar for cortical neurons and neurons in the lateral geniculate nucleus (LGN) and indicate that subcortical mechanisms likely play a major role in establishing the degree of effect displayed by downstream neurons. Finally, results show that LGN and cortical neurons experience a contrast-dependent phase advance in their visual response. This phase advance is most pronounced for cortical neurons indicating a role for both subcortical and cortical mechanisms.

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The Role of Spared Calcarine Cortex and Lateral Occipital Cortex in the Responses of Human Hemianopes to Visual Motion

Journal of Cognitive Neuroscience ◽

10.1162/089892904322984517 ◽

2004 ◽

Vol 16 (2) ◽

pp. 204-218 ◽

Cited By ~ 33

Author(s):

Antony B. Morland ◽

Sandra Lê ◽

Erin Carroll ◽

Michael B. Hoffmann ◽

Alidz Pambakian

Keyword(s):

Visual Cortex ◽

Primary Visual Cortex ◽

Visual Motion ◽

Neural Mechanism ◽

Visual Pathways ◽

The Other ◽

Visual Response ◽

Visual Responses ◽

Behavioral Experiments ◽

Residual Vision

Some patients, who are rendered perimetrically blind in one hemifield by cortical lesions, nevertheless exhibit residual visual capacities within their field defects. The neural mechanism that mediates the residual visual responses has remained the topic of considerable debate. One explanation posits the subcortical visual pathways that bypass the primary visual cortex and innervate the extrastriate visual areas as the substrate that underlies the residual vision. The other explanation is that small islands of the primary visual cortex remain intact and provide the signals for residual vision. We have performed behavioral and functional magnetic resonance imaging experiments to investigate the validity of the two explanations of residual vision. Our behavioral experiments indicated that of the seven hemianopes tested, two had the ability to discriminate the direction of a drifting grating. This residual visual response was shown with fMRI to be the result of spared islands of calcarine cortical activity in one of the hemianopes, whereas only lateral occipital activity was documented in the other patient. These results indicate that the underlying neural correlates of residual vision can vary between patients. Moreover, our study emphasizes the necessity of ruling out the presence of islands of preserved function and primary visual cortex before assigning residual visual capacities to the properties of visual pathways that bypass the primary visual cortex.

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