AN ALTERNATIVE TO THE BIOMAGNETIC FORWARD PROBLEM IN A REALISTICALLY SHAPED HEAD MODEL, THE WEIGHTED VERTICES

The ''weighted vertices'' (WV), an alternative in solving the biomagne tic forward problem (BFP) for a realistically shaped head (RSH) model are presented. This proposed approach differs from the others in the w ay some terms in the governing integral equations are defined. The eff ects that WV has on important issues such as the ''auto solid angle'' and ''stability of equations'' are discussed. Two variants of the WV a pproach, i.e., the ''linear weight'' and the ''quadratic weight,'' hav e been developed, and comparison of results produced by these two appr oaches shows that the implementation of quadratic elements to evaluate the integral produces significant improvements. This study is done wi th a focus on magnetic rather than electric phenomena, so a homogeneou s conductor has been used in the numerical example. However, the thoug hts behind this proposed method can be easily extended for cases where inhomogeneous conductors are involved. Significant improvement in the accuracy of the forward problem has been observed by use of the WV ap proach.