Optimizing an array of sensors for magnetoencephalography

Modern magnetoencephalographic (MEG) instruments estimate the location of endocranial current sources with an array of magnetometers. The authors provide a technique for computing the magnetometer orientations that achieve minimum mean-square localization error. They thereby show that the radial orientations in a commonly-used array are non-optimal, and suggest a simple modification that significantly improves the array's performance.