Multidimensional Inverse Current Source Density in different geometries

Abstract

Event Abstract Back to Event Multidimensional Inverse Current Source Density in different geometries Daniel K. Wojcik1*, Szymon Leski1, Daniel A. Swiejkowski1, Ewa Kublik1 and Andrzej Wrobel1 1 Nencki Institute of Experimental Biology, Poland Growing availability of multi-electrode recordings has brought up the issue of efficient extraction of current source density generating the recorded potentials. While classical approach to CSD extraction can be viable in one dimension, in three dimensions it enforces discarding of majority of data. Inverse Current Source Density Method was proposed [1] to overcome certain deficiencies in the classical approach. We show its application to three dimensional set of potentials evoked by stimulation of a bunch of whiskers, recorded in a slab of the rat forebrain on a grid of 4x5x7 positions [2]. We compare the efficiency of the traditional CSD and variants of inverse CSD methods using several fidelity measures on different test data to investigate when one of the methods is superior to the others. The general framework of the method is to assume a particular plausible form of CSD distribution described by as many parameters as recording points. For measurements taken at points of a cubic grid one can take a set of cubic splines in 3D spanned on a grid of the same size. The relation between the CSD and the measured potentials is then given by a linear invertible operator. We explore the application of this idea to more general cases looking towards some available multi-electrode array geometries. This work was financed from the Polish Ministry of Science and Higher Education research grants N401 146 31/3239, PBZ/MNiSW/07/2006/11 and COST/127/2007.