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Biomag 96 pp 393-396 | Cite as

Current Density Reconstructions Using the L1 Norm

  • M. Wagner
  • H.-A. Wischmann
  • M. Fuchs
  • T. Köhler
  • R. Drenckhahn

Abstract

A major goal in biomagnetism is the reconstruction of current distributions without making preliminary assumptions about number and temporal properties of the sources to be reconstructed. We propose a new current density reconstruction method that computes source images with high resolution and small blurring. A nonlinear functional, the L1-norm, is used as a source constraint. The L1-norm is the sum of absolute current densities. A simple Simulation shows, that the L1-norm does neither impose artificial smoothness nor sharpness upon the reconstructed sources. We have implemented three different minimization schemes for the L1-norm, which we compare against each other and against the MNLS (minimum norm least squares, L2-norm) method [1]. Unlike the L1-norm method described earlier [2], our approaches tolerate noisy data and arbitrary source orientations.

Keywords

Single Dipole Reconstructed Source Simulated Source Source Configuration Magnetic Source Image 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 2000

Authors and Affiliations

  • M. Wagner
    • 1
  • H.-A. Wischmann
    • 1
  • M. Fuchs
    • 1
  • T. Köhler
    • 1
  • R. Drenckhahn
    • 1
  1. 1.Philips Research HamburgHamburgGermany

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