Orientation column

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

Responses of striate cortical cells to moving edges of different curvatures

Abstract: The responses of twenty cells to stimuli of varying curvature were measured in cat's striate cortex. All the investigated cells were sensitive to the orientation of lines and not hypercomplex. Fourteen cells showed a systematic change of response with curvature. The optimal curvatures of the cells were distributed over the whole range investigated. Six cells were insensitive to curvature. The responses from all the typical simple cells (8) varied with curvature, whereas all the complex cells (5) were insensitive to curvature changes. The curvature tuning curves were broad and the variability to individual stimuli was high, independent on whether the cell responded best to straight or to curved edges. The findings do not support the view that individual cells of area 17 could detect curvature.

Intelligent Line Segment Perception With Cortex-Like Mechanisms

Abstract: This paper proposes a novel general framework for line segment perception, which is motivated by a biological visual cortex, and requires no parameter tuning. In this framework, we design a model to approximate receptive fields of simple cells. More importantly, the structure of biological orientation columns is imitated by organizing artificial complex and hypercomplex cells with the same orientation into independent arrays. Besides, an interaction mechanism is implemented by a set of self-organization rules. Enlightened by the visual topological theory, the outputs of these artificial cells are integrated to generate line segments that can describe nonlocal structural information of images. Each line segment is evaluated quantitatively by its significance. The computation complexity is also analyzed. The proposed method is tested and compared to state-of-the-art algorithms on real images with complex scenes and strong noises. The experiments demonstrate that our method outperforms the existing methods in the balance between conciseness and completeness.

The distribution of corticotectal projection neurons correlates with the interblob compartment in macaque striate cortex

Abstract: While much attention has been given to the correlation between cytochrome-oxidase (CO) compartments and patterns of cortico-cortical projections originating from supragranular layers in the striate cortex, little is known in this regard about patterns of cortico-subcortical projections originating from infragranular cortex. We studied the tangential distribution of the striate cortex neurons projecting to the superior colliculus and used two approaches to analyze the relationship of this distribution to the arrangement of CO "blobs." First, chi-square analysis indicated that significantly fewer labeled neurons were found within the CO blob compartment than the number expected for a random distribution. Second, spatial cross-correlation analysis--which circumvents the inherent subjectivity of delineating blob boundaries--revealed an area around blob centers in which there was a decreased probability of encountering labeled cells. The size of this area compared well with that of our outlines of CO blobs. We conclude that corticotectal projection neurons in the striate cortex are distributed preferentially within the interblob compartment of the infragranular striate cortex. These results demonstrate that the spatial distribution of cortico-subcortical projection neurons within infragranular cortex can correlate with the CO architecture of the primary visual cortex.