The primary visual cortex has a map of multiple visual parameters whose topographic relations remain poorly understood. A new study (Nauhaus et al., 2016) reveals a nearly geometric map-topography that coexists within a remarkably precise representation of visual space.

Shear has been known to exist for many years in the topographic structure of the primary visual cortex, but has received little attention in the modeling literature. Although the topographic map of V1 is largely conformal (i.e. zero shear), several groups have observed topographic shear in the region of the V1/V2 border. Furthermore, shear has also been revealed by anisotropy of cortical magnif...

In this research we propose learning a controller for a mobile robot with a topographic Restricted Boltzmann machine (tRBM). The topographic RBM generalizes the previously proposed Map-Initialized Perceptron (MIP) to a probabilistic model which learns a joint distribution of sensory states and continuous actions. Keywords— Topographical Structure, Restricted Boltzmann Machine, Mobile Robot, Imi...

The High Resolution Stereo Camera (HRSC) on board of the European space mission Mars Express provides multispectral digital image data in high resolution as well as the systematic stereo coverage of our neighbouring planet. Thus, these data particularly meet the requirements of stereophotogrammetric processing and cartographic applications. Based on HRSC imagery, large-scale topographic and the...

Topographic maps are the primary means of relaying spatial information in the brain. Understanding the mechanisms by which they form has been a goal of experimental and theoretical neuroscientists for decades. The projection of the retina to the superior colliculus (SC)/tectum has been an important model used to show that graded molecular cues and patterned retinal activity are required for top...

A self-organizing map (SOM) algorithm can generate a topographic map from a high-dimensional stimulus space to a low-dimensional array of units. Because a topographic map preserves neighborhood relationships between the stimuli, the SOM can be applied to certain types of information processing such as data visualization. During the learning process, however, topological defects frequently emerg...

National administration of surveying, mapping and geoinformation started to launch the project of national fundamental geographic information database dynamic update in 2012. Among them, the 1:50000 database was updated once a year, furthermore the 1:250000 database was downsized and linkage-updated on the basis. In 2014, using the latest achievements of 1:250000 database, comprehensively updat...

We introduce relational variants of neural topographic maps including the selforganizing map and neural gas, which allow clustering and visualization of data given in terms of a pairwise similarity or dissimilarity matrix. It is assumed that this matrix originates from an euclidean distance or dot product, respectively, however, the underlying embedding of points is unknown. One can equivalentl...

Optimizing the performance of self-organizing feature maps like the Kohonen map involves the choice of the output space topology. We present a topographic product which measures the preservation of neighborhood relations as a criterion to optimize the output space topology of the map with regard to the global dimensionality DA as well as to the dimensions in the individual directions. We test t...