Neuromagnetic localization performed by using planar gradiometer configurations

The spatial discrimination of planar and axial gradiometers is compared by using a spatial filtering model. By measuring somatosensory evoked fields, equivalent current dipoles were localized with the use of planar gradiometer outputs. The planar configurations were obtained by combining, in a proper way, the outputs of a four-channel biomagnetic system. It was observed that with a proper signal-to-noise ratio, the use of the planar configurations did not significantly affect the localization precision.