| 摘要 |
PURPOSE:To automatically obtain a solution of showing the actually existing number of current dipoles by assuming a larger estimated number of current dipoles than the estimated number of current dipoles in the body, in the case of estimating current distribution in the body by measuring a magnetic field, generated from this body, in a plurality of measuring points in the outside of the living body. CONSTITUTION:A position of the m-th measuring point is shown by a vector rm, and a measuring amount of a magnetic field in that point is set to Dm by assuming M for a number of measuring points of a head part surface. A number N of current dipoles are assumed contained in the interior of a brain. The number N are set a little larger than an estimated number of current dipoles. An estimated position of thus assumed estimated current dipole is shown by rn, and an estimated current vector is shown by qn. A magnetic field Dm (m=1,..., M), generated in the measuring point by the current dipole thus assumed, is obtained by calculation. That is, Dm can be called a virtual magnetic field measuring value obtained from the estimated current dipole. Next, by optimized arithmetic operation, an estimated value of minimum cost function is obtained by displacing the position estimated value rn and the current vector estimated value qn of the assumed current dipole. |
