BCM Network Develops Orientation Selectivity and Ocular Dominance in Natural Scene Environment.

1996 ◽  
Author(s):  
Harel Shouval ◽  
Nathan Intrator ◽  
Leon N. Cooper
1997 ◽  
Vol 37 (23) ◽  
pp. 3339-3342 ◽  
Author(s):  
Harel Shouval ◽  
Nathan Intratorj ◽  
Leon N. Cooper

1976 ◽  
Vol 39 (3) ◽  
pp. 512-533 ◽  
Author(s):  
J. R. Wilson ◽  
S. M. Sherman

1. Receptive-field properties of 214 neurons from cat striate cortex were studied with particular emphasis on: a) classification, b) field size, c) orientation selectivity, d) direction selectivity, e) speed selectivity, and f) ocular dominance. We studied receptive fields located throughtout the visual field, including the monocular segment, to determine how receptivefield properties changed with eccentricity in the visual field.2. We classified 98 cells as "simple," 80 as "complex," 21 as "hypercomplex," and 15 in other categories. The proportion of complex cells relative to simple cells increased monotonically with receptive-field eccenticity.3. Direction selectivity and preferred orientation did not measurably change with eccentricity. Through most of the binocular segment, this was also true for ocular dominance; however, at the edge of the binocular segment, there were more fields dominated by the contralateral eye.4. Cells had larger receptive fields, less orientation selectivity, and higher preferred speeds with increasing eccentricity. However, these changes were considerably more pronounced for complex than for simple cells.5. These data suggest that simple and complex cells analyze different aspects of a visual stimulus, and we provide a hypothesis which suggests that simple cells analyze input typically from one (or a few) geniculate neurons, while complex cells receive input from a larger region of geniculate neurons. On average, this region is invariant with eccentricity and, due to a changing magnification factor, complex fields increase in size with eccentricity much more than do simple cells. For complex cells, computations of this geniculate region transformed to cortical space provide a cortical extent equal to the spread of pyramidal cell basal dendrites.


2002 ◽  
Vol 88 (4) ◽  
pp. 1933-1940 ◽  
Author(s):  
Chris J. Beaver ◽  
Quentin S. Fischer ◽  
Qinghua Ji ◽  
Nigel W. Daw

We have previously shown that the protein kinase A (PKA) inhibitor, 8-chloroadenosine-3′,5′–monophosphorothioate (Rp-8-Cl-cAMPS), abolishes ocular dominance plasticity in the cat visual cortex. Here we investigate the effect of this inhibitor on orientation selectivity. The inhibitor reduces orientation selectivity in monocularly deprived animals but not in normal animals. In other words, PKA inhibitors by themselves do not affect orientation selectivity, nor does monocular deprivation by itself, but monocular deprivation in combination with a PKA inhibitor does affect orientation selectivity. This result is found for the receptive fields in both deprived and nondeprived eyes. Although there is a tendency for the orientation selectivity in the nondeprived eye to be higher than the orientation selectivity in the deprived eye, the orientation selectivity in both eyes is considerably less than normal. The result is striking in animals at 4 wk of age. The effect of the monocular deprivation on orientation selectivity is reduced at 6 wk of age and absent at 9 wk of age, while the effect on ocular dominance shifts is less changed in agreement with previous results showing that the critical period for orientation/direction selectivity ends earlier than the critical period for ocular dominance. We conclude that closure of one eye in combination with inhibition of PKA reduces orientation selectivity during the period that orientation selectivity is still mutable and that the reduction in orientation selectivity is transferred to the nondeprived eye.


2019 ◽  
Author(s):  
Xize Xu ◽  
Jianhua Cang ◽  
Hermann Riecke

AbstractIn mouse visual cortex, right after eye-opening binocular cells have different orientation preferences for input from the two eyes. With normal visual experience during a critical period, these orientation preferences shift and eventually become well matched. To gain insight into the matching process, we developed a computational model of a cortical cell receiving - via plastic synapses - orientation selective inputs that are individually monocular. The model captures the experimentally observed matching of the orientation preferences, the dependence of matching on ocular dominance of the cell, and the relationship between the degree of matching and the resulting monocular orientation selectivity. Moreover, our model puts forward testable predictions: i) the matching speed increases with initial ocular dominance and decreases with initial orientation selectivity; ii) matching proceeds faster than the sharpening of the orientation selectivity, suggesting that orientation selectivity is not a driving force for the matching process; iii) there are two main routes to matching: the preferred orientations either drift towards each other or one of the orientations switches suddenly. The latter occurs for cells with large initial mismatch and can render the cell monocular. We expect that these results provide insight more generally into the development of neuronal systems that integrate inputs from multiple sources, including different sensory modalities.New & NoteworthyAnimals gather information through multiple modalities (vision, audition, touch, etc). These information streams have to be merged coherently to provide a meaningful representation of the world. Thus, for neurons in visual cortex V1 the orientation selectivities for inputs from the two eyes have to match to enable binocular vision. We analyze the postnatal process underlying this matching using computational modeling. It captures recent experimental results and reveals interdependence between matching, ocular dominance, and orientation selectivity.


1976 ◽  
Vol 39 (6) ◽  
pp. 1320-1333 ◽  
Author(s):  
P. H. Schiller ◽  
B. L. Finlay ◽  
S. F. Volman

1. Quantitative analyses of orientation specificity and ocular dominance were carried out in striate cortex of the rhesus monkey. 2. Sharpness of orientation selectivity was greater for simple (S type) than for complex (CX type) cells. CX-type cells became more broadly tuned in the deeper cortical layers: S-type cells were equally well tuned throughout the cortex. 3. Sharpness of orientation selectivity for S-type cells was similar at all retinal eccentricities studied (0 degrees - 20 degrees from the fovea):in CX-type cells orientation selectivity decreased slightly with increasing eccentricity. 4. The orientation tuning of binocular cells was similar when mapped separately through each eye. 5. Orientation selectivity and direction selectivity are independent of each other, suggesting that separate neural mechanisms give rise to them. 6. More CX-type cells can be binocularly activated than S-type cells (88% versus 49%). The ocular dominance of S-type cells is similar in all cortical layers: for CX-type cells there is an increase in the number of cells in ocular-dominance category 4 in layers 5 and 6.


2020 ◽  
Vol 123 (4) ◽  
pp. 1305-1319 ◽  
Author(s):  
Xize Xu ◽  
Jianhua Cang ◽  
Hermann Riecke

In mouse visual cortex, right after eye opening binocular cells have different preferred orientations for input from the two eyes. With normal visual experience during a critical period, these preferred orientations evolve and eventually become well matched. To gain insight into the matching process, we developed a computational model of a cortical cell receiving orientation selective inputs via plastic synapses. The model captures the experimentally observed matching of the preferred orientations, the dependence of matching on ocular dominance of the cell, and the relationship between the degree of matching and the resulting monocular orientation selectivity. Moreover, our model puts forward testable predictions: 1) The matching speed increases with initial ocular dominance. 2) While the matching improves more slowly for cells that are more orientation selective, the selectivity increases faster for better matched cells during the matching process. This suggests that matching drives orientation selectivity but not vice versa. 3) There are two main routes to matching: the preferred orientations either drift toward each other or one of the orientations switches suddenly. The latter occurs for cells with large initial mismatch and can render the cells monocular. We expect that these results provide insight more generally into the development of neuronal systems that integrate inputs from multiple sources, including different sensory modalities. NEW & NOTEWORTHY Animals gather information through multiple modalities (vision, audition, touch, etc.). These information streams have to be merged coherently to provide a meaningful representation of the world. Thus, for neurons in visual cortex V1, the orientation selectivities for inputs from the two eyes have to match to enable binocular vision. We analyze the postnatal process underlying this matching using computational modeling. It captures recent experimental results and reveals interdependence between matching, ocular dominance, and orientation selectivity.


2005 ◽  
Vol 22 (3) ◽  
pp. 325-343 ◽  
Author(s):  
C. MILLERET ◽  
P. BUSER ◽  
L. WATROBA

Neurones activated through the corpus callosum (CC) in the cat visual cortex are known to be almost entirely located at the 17/18 border. They are orientation selective and display receptive fields (RFs) distributed along the central vertical meridian of the visual field (“visual midline”). Most of these cells are binocular, and many of them are activated both from the contralateral eye through the CC, and from the ipsilateral eyeviathe direct retino-geniculo-cortical (GC) pathway. These two pathways do not carry exactly the same information, leading to interocular disparity between pairs of RFs along the visual midline. Recently, we have demonstrated that a few weeks of unilateral paralytic strabismus surgically induced at adulthood does not alter the cortical distribution of these units but leads to a loss of their orientation selectivity and an increase of their RF size, mainly toward the ipsilateral hemifield when transcallosally activated (Watroba et al., 2001). To investigate interocular disparity, here we compared these RF changes to those occurring in the same neurones when activated through the ipsilateral direct GC route. The 17/18 transition zone and the bordering medial region within A17 were distinguished, as they display different interhemispheric connectivity. In these strabismics, some changes were noticed, but were basically identical in both recording zones. Ocular dominance was not altered, nor was the spatial distribution of the RFs with respect to the visual midline, nor the amplitude of position disparity between pairs of RFs. On the other hand, strabismus induced a loss of orientation selectivity regardless of whether neurones were activated directly or through the CC. Both types of RFs also widened, but in opposite directions with respect to the visual midline. This led to changes in incidences of the different types of position disparity. The overlap between pairs of RFs also increased. Based on these differences, we suggest that the contribution of the CC to binocular vision along the midline in the adult might be modulated through several intrinsic cortical mechanisms.


1983 ◽  
Vol 61 (12) ◽  
pp. 1433-1441 ◽  
Author(s):  
David H. Hubel ◽  
Margaret S. Livingstone

When the monkey striate cortex is stained for the mitochondrial enzyme cytochrome oxidase a polka-dot pattern of patches or blobs is observed in layers 2 and 3 and more faintly in layers 5 and 6. In the macaque these blobs are aligned along the centers of ocular dominance columns. Cells within blobs lack the orientation selectivity and instead have the simpler concentric center-surround fields common in geniculate cells. Blob cells are specifically concerned with color and in particular with maintaining color constancy despite marked changes in the spectral content of the light source.


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