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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: Responses of striate cortical neurones to bars of optimal orientation and width, moving with fixed velocity, were recorded in the lightly anaesthetized cat and maximal effects were obtained with adapting gratings of optimal velocity and spatial frequency.
Abstract: Responses of striate cortical neurones to bars of optimal orientation and width, moving with fixed velocity, were recorded in the lightly anaesthetized cat. Effects of periods of pre-adaptation with square-wave gratings of variable spatial frequency and velocity, drifting continuously in each cell's preferred or null directions, were investigated. Variations of cells' directional bias and responsiveness to oriented bars were assessed in relation to the degree and time-course of pre-adaptation to drifting gratings, compared with the preceding level of firing when exposed to uniform backgrounds of the same average luminance. All cells showed some susceptibility to pre-adapting moving gratings: subsequent responses to a bar were initially depressed in the direction of pre-adaptation and, in direction-biased or bidirectional cells, were enhanced in the opposite direction, compared with bar responses following exposure merely to a uniform background. These effects were strongest and most consistent amongst standard complex cells and weakest amongst special complex cells: maximal effects were obtained with adapting gratings of optimal velocity and spatial frequency.

61 citations

Journal ArticleDOI
TL;DR: It is shown that the retinotopic organization of the lateral peristriate cortex remains largely unchanged after lesions in area 17, and V I appears similar to that of the albino raO s and other rodents.

61 citations

01 Jan 2004
TL;DR: Research in receptive fields and suppressive fields in lateral geniculate nucleus (LGN) and in primary visual cortex (V1) is summarized and it is hoped that this term will find wide acceptance to describe responses of both LGN and V1 neurons.
Abstract: Initial models proposed that these operations are weighted sums, with weights given by a neuron’s receptive field. These models explain the basic features of response selectivity. They were later extended to explain a number of suppressive effects originating within and outside the region of the receptive field. The resulting models rely on division. In this division, the receptive field feeds into the numerator, and the denominator is provided by a larger, non-classical suppressive field. While the receptive field confers to a neuron the basic selectivity for stimulus properties, the suppressive field modulates responsiveness. A divisive suppressive field confers to neurons in early visual system a number of computational advantages. Recent evidence in higher cortical areas suggests that the modulation of divisive suppression is the primary means of operation of visual attention. In this chapter I summarize research in receptive fields and suppressive fields in lateral geniculate nucleus (LGN) and in primary visual cortex (V1). In the following, I refer to a “suppressive field” as though this term had wide acceptance. In reality, the concept has been proposed only for LGN neurons (Levick et al., 1972), and lies forgotten since 30 years. My hope is that it will find wide acceptance to describe responses of both LGN and V1 neurons. Receptive fields in LGN

60 citations

Journal ArticleDOI
TL;DR: Single neurons were recorded in the striate visual cortex of the old-world monkey Macacus nemestrinus, and the laminar specificity of the boutons was very much more precise in the monkey than in the cat.
Abstract: Single neurons were recorded in the striate visual cortex (area 17) of the old-world monkey Macacus nemestrinus. Eight pyramidal neurons, seven spiny stellate neurons, two basket cells, a clutch cell, and a chandelier cell were filled intracellularly with HRP. Their receptive fields were consistent with previous single-unit studies. Their axonal arbors were less elaborate than in equivalent neurons in the cat, but the laminar specificity of the boutons was very much more precise in the monkey than in the cat. Nevertheless, the basic cortical circuits in cat and monkey appear to be very similar.

60 citations

Journal ArticleDOI
TL;DR: It is shown that the “cortical images” undergo simple shifts whenever the retinal images are scaled or rotated, and the main neuroanatomical and neurophysiological properties taken into account are: the linear increase of the receptive fields diameter with eccentricity, the constancy of the overlap factor and the topological transformation operated upon the retina image by the retino-corticals connection.
Abstract: A model of the early stages of the visual system is presented, with particular reference to the region of the visual field outside the fovea and to the class of retinal and lateral geniculate nucleus cells which are most active in the processing of pattern information (X-cells). The main neuroanatomical and neurophysiological properties taken into account are: the linear increase of the receptive fields diameter with eccentricity, the constancy of the overlap factor and the topological transformation operated upon the retinal image by the retino-cortical connection. The type of filtering taking place between the retina and the visual cortex is analyzed and some simulations are presented. It is shown that such a filtering is of a band-pass space variant type, with center frequencies that decrease from the center (i.e. the fovea) toward the periphery of the visual field. This processing is "form invariant" under linear scaling of the input. Moreover, considering the properties of the retino-cortical connection, it is shown that the "cortical images" undergo simple shifts whenever the retinal images are scaled or rotated.

60 citations


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