Brain mapping: a contribution to linear interpolation.

Topographic mapping of brain electrical activity has become a powerful tool in neurological diagnosis. Maps are obtained from a reduced number of actual measurements by means of mathematical interpolation. Most of these systems use linear combination of the values measured and, in spite of its importance, the choice of the exponent "n" in the weighting function is made ad hoc. In this paper we present a critical analysis of such method and propose an objective criterion for the estimation of that exponent. As well, we propose another criterion for determining the number of leads used in the interpolation of each point.