Orientation column

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

Using Log-Gabor Filter Array to Estimate Seismic Dip and Azimuth

Abstract: In this paper, we introduce a method of orientation estimation in seismic data. Unlike conventional methods of orientation estimation with a context window, our method is inspired by the neural mechanism of visual perception. The primary visual cortex in the brain contains orientation columns, which are composed of an array of orientation detectors. A log-Gabor filter with a specific orientation and scale configuration simulates the neuronal mechanism of the orientation detector, while an array of such filters simulates the orientation columns. The resulting orientation is derived at the sample level of the input seismic data: the filter response competes with each other in the array, and the maximum response defines the seismic orientation. Our proposed method has many applications in seismic interpretation, e.g., calculating the volumetric azimuth and dip attributes without picking, guiding seismic attribute computation, and detecting seismic texture patterns.

Scene Segmentation and Boundary Estimation in Primary Visual Cortex

Abstract: Neurons are described as the core computational unit associated with intelligence of primates but very little is understood about the biological and physiochemical processes associated that results in their robust behavior. Numerous unique morphology of neurons are stacked with either precise connectivity in some regions, whereas significantly dissimilar connectome specificity in others, shaping cognitive behavior that is yet to be unraveled. In this proposed work, parasol RGC layers with moderate receptive fields connected to ON bipolar cell in the primary region projecting onto magnocellular region and orientation selectivity in magnocellular region have been explored. Result suggests segmentation type behavior due to connectivity with ON bipolar cells in the striate cortex of primary visual cortex whereas boundary estimation type behavior due to orientation selectivity in the V2 region of primary visual cortex.

An Orientation Column-Inspired Contour Representation and Its Application in Shape-Based Recognition

Abstract: Recognizing an object from its background in a real-world image is always a very challenging task. During the recognition process, shape (or contour) information of an object is useful. In this paper, we build a bio-inspired contour detection model which can organize the edge information into a structured data form. Biological primary visual cortex, which can be simulated by computer, is specialized in detecting orientation of edge to producing a set of line segments. Then we propose the concept of route that indicates a continuous part of the contour. The set of line segments is divided into several routes which are the basic processing units of following recognition steps.

The pairwise phase consistency in cortical network and its relationship with neuronal activation

Abstract: Gamma-band neuronal oscillation and synchronization with the range of 30-90 Hz are ubiquitous phenomenon across numerous brain areas and various species, and correlated with plenty of cognitive functions. The phase of the oscillation, as one aspect of CTC (Communication through Coherence) hypothesis, underlies various functions for feature coding, memory processing and behaviour performing. The PPC (Pairwise Phase Consistency), an improved coherence measure, statistically quantifies the strength of phase synchronization. In order to evaluate the PPC and its relationships with input stimulus, neuronal activation and firing rate, a simplified spiking neuronal network is constructed to simulate orientation columns in primary visual cortex. If the input orientation stimulus is preferred for a certain orientation column, neurons within this corresponding column will obtain higher firing rate and stronger neuronal activation, which consequently engender higher PPC values, with higher PPC corresponding to higher firing rate. In addition, we investigate the PPC in time resolved analysis with a sliding window.