Forward and inverse methods in event related potential imaging using a resistor mesh model

A spherical head model based on a resistor mesh is presented. Each resistor corresponds to the conducting electrical properties of a tissue volume. A current dipole is simulated by an electrical current source connected between two nodes in this mesh. The direct problem is solved and the accuracy of this model is evaluated in comparison with the analytical solution. The results show that the resistor mesh provides correct potential and scalp current density values. The model structure makes it easy to introduce conductivity heterogeneities such as stroke and skull anisotropy. First trials of an inverse method are also presented.