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Orientation column

About: Orientation column is a research topic. Over the lifetime, 1142 publications have been published within this topic receiving 130169 citations.


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Journal ArticleDOI
TL;DR: Most receptive fields of neurons in the visual cortex of rats could be mapped with moving and stationary stimuli and neurons were most effectively driven by moving stimuli.

58 citations

Journal ArticleDOI
TL;DR: Responses of single cells in the striate cortex of a behaving monkey were studied while the eye movements of fixation were monitored with high precision and the eye position signal was used to stabilize the image on the retina.

58 citations

Journal ArticleDOI
TL;DR: Double intracellular recordings showed that synaptic reinforcement is not confined to the depolarized postsynaptic neuron, but is also observed in adjacent but not coactivated neurons.
Abstract: IN the mammalian CNS, long term potentiation can be induced by repeatedly pairing presynaptic stimulation with postsynaptic depolarization of a single cell, similar to a model proposed by Hebb, that synaptic strengthening occurs as a result of correlated pre- and postsynaptic activity. However, our

58 citations

Journal ArticleDOI
TL;DR: It is concluded that monocularly and binocularly sutured cats develop by qualitatively different mechanisms, with the former facing competition between central synapses related to each eye is a prominent feature of geniculocortical development, whereas, for the latter, such specific forms of genimedial development may not obtain.
Abstract: 1. We studied the receptive fields of 171 striate cortical neurons from 17 cats raised with binocular lid suture. Of these, 102 fields were within 10 degrees of the area centralis and the remaining 69 were at least 38 degrees from the vertical meridian. 2. Based on their different response properties, cells were divided into three broad groups: the mappable cells (49%) had clearly defined receptive fields, the unmappable cells (31%) were activated by visual stimuli but had diffuse fields which could not be hand plotted, and the visually inexcitable cells (20%) could not be activated by visual stimuli. Very few (less than or equal to 12% of the total sample) normal simple or complex cells could be found. 3. Orientation selectivity was assessed in these cells. Only 12% displayed orientation selectivity within normal bounds, and these were all mappable cells. None of the unmappable cells had discernible orientation selectivity. 4. Ocular dominance was assessed for 62 of the centrally located receptive fields. Among mappable cells, there was an abnormally low proportion of binocular fields, while no such abnormality was seen for unmappable cells. 5. For 47 of the neurons, average response histograms were compiled for moving stimuli of various parameters in an effort to evoke the maximum discharge or peak response. This peak response was normal for mappable cells but reduced for unmappable cells. 6. We devised a technique for studying potential inhibitory receptive-field zones in these neurons, validated the method in normal striate cortex, and used it to test 20 mappable cells in the lid-sutured cats. None showed the pattern of strong inhibitory side bands seen in normal simple cells, although six showed weak or abnormal inhibitory zones. Interestingly, six of the seven visually inexcitable cells tested by this method had purely inhibitory receptive fields. 7. The effects of binocular suture were essentially identical for the binocular and monocular segments since the cell types and their response properties did not differ between these two areas of cortex. Furthermore, the cortical monocular segments of these cats seemed qualitatively different from the deprived cortical monocular segment after monocular suture. This extends an analogous difference for these cats reported for the monocular segments of the lateral geniculate nucleus. We thus conclude that monocularly and binocularly sutured cats develop by qualitatively different mechanisms. For the former, competition between central synapses related to each eye is a prominent feature of geniculocortical development, whereas, for the latter, such specific forms of geniculocortical development may not obtain.

58 citations

Journal ArticleDOI
TL;DR: It is suggested that contour alignment alters visual processing in rats, despite their lack of orientation columns in the visual cortex, in the first report that the arrangement of visual features relative to each other affects visual behavior in rats.
Abstract: We measure rats' ability to detect an oriented visual target grating located between two flanking stimuli ("flankers"). Flankers varied in contrast, orientation, angular position, and sign. Rats are impaired at detecting visual targets with collinear flankers, compared to configurations where flankers differ from the target in orientation or angular position. In particular, rats are more likely to miss the target when flankers are collinear. The same impairment is found even when the flanker luminance was sign-reversed relative to the target. These findings suggest that contour alignment alters visual processing in rats, despite their lack of orientation columns in visual cortex. This is the first report that the arrangement of visual features relative to each other affects visual behavior in rats. To provide a conceptual framework for our findings, we relate our stimuli to a contrast normalization model of early visual processing. We suggest a pattern-sensitive generalization of the model which could account for a collinear deficit. These experiments were performed using a novel method for automated high-throughput training and testing of visual behavior in rodents.

57 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20231
20223
20212
20208
20192
20189