Abstract
P. Berg and M. Scherg's fast computation method (see Electroenceph. Clin. Neurophysiol., vol. 90, p.58-64, 1994) is extended to multilayer anisotropic spheres. The Berg parameters can be dependent upon a dipole radial parameter or not, depending on the actual sphere conductivities and the layer the dipole is within. To find the Berg parameters, no specific electrode locations are required. Berg and Scherg's method is generally applicable whenever de Munck and Peters's (1993) addition-subtraction method can be used.