present research

Turtle cortex

Dynamics of the turtle visual cortex
Wenxue Wang, Bijoy K. Ghosh

A large scale model of the turtle visual cortex was built with GENESIS software package. The model contains five populations of neurons: lateral pyramidal and medial pyramidal cells(excitatory  cells); stellate, horizontal and subpial cells(inhibitory cells).  With the detailed compartmental model of subpial cells and the large scale model, the biophysical properties of subpial cells were examined and it is indicated that the responses of subpial cells to simulated visual stimuli consist of two phases. More ...

Design of sensor networks
Wenxue Wang, Bijoy K. Ghosh

 Waves of activity produced by the large scale model of turtle visual cortex with visual stimuli encodes visual information. In this study, we address how images of objects in three dimensional space from multiple sensors are encoded using a sparse coding with an overcomplete set of basis functions and subsequently how the codes from individual sensors are fused to produce a data stream of vectors. More ...
senser networks

Encoding Images  Bio-inspired Encoding of Images with Spatiotemporal Activity Waves
Jenner J. Joseph, Bijoy K. Ghosh

The visual cortex of freshwater turtles can be viewed as a pattern generating system when stimulated by visual targets. We aspire to build a model of the visual pathway using a sequence of natural scenes as stimuli. This is done in two phases: In the forward phase, each image is mapped onto a fixed architecture given by the distribution of the turtle’s lateral geniculate nucleus (LGN) cells. These cells are viewed as sensing devices and we optimize the representation of the natural inputs with respect to the LGN distribution. More ...

retinal networks

Modeling of retinal networks
Xihua Dong, Bijoy K. Ghosh

The goal of this project is to model the retina of the freshwater
turtles. We will do it in three steps: Firstly,adjust the parameters of
single neuron model so that the output of fit the experiments well;
secondly,build the network model and compare with the
experimental results; finally Use our model to study how to decode
information from the output of a population of ganglion cells. More...

gene networks Dynamical Systems Approach to Modelling Gene Expression Profiles
Thanura Elvitigala, Bijoy K. Ghosh

The goal of this project is to apply various engineering techniques including cluster analysis and sequnce searching to identify corregulated genes and their similarities. Microarray data from different experiments are being analyzed in order to identify main behavioral patterns in genes. These expression profiles are then used to build dynamical systems which can axproximate such behaviors. More ...

synaptic adaptation

Synaptic Adaptation in the Visual Cortex Model

Zachary V. Frendenburg, Bijoy K. Ghosh

This project explores the effects of Hebbian learning on the wave activity patterns of the freshwater cortex model. The Hebbian synaptic weight learning rule is the most basic and wide spread learning rule used in neuromodeling. However, to date there has been little work done in applying this simple learning mechanism to significantly large scale cortex models. The visual cortex of a freshwater turtle, when stimulated by a pattern of light, produces waves of activity that have been both recorded experimentally and simulated using a large scale model cortex. More ...

CBCIS collaborates with several reseach groups with diverse research interests in an attempt to bring together different skills. As a part of this initiative presently we are working with the Biology Department of Washington University.

In addition some research activities are carried out in collaboration with the Medical School of the Washington University .


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