[Registration of visual evoked neuromagnetic fields following partial field stimulation of the fovea]

Visual evoked neuromagnetic fields were recorded after stimulation of the right and left foveal half-field and of the right lower and upper quadrant. A contralateral topography of the dominant complex of the visual evoked field was measured on the skull after right and left half-field stimulation. After switching from the right half-field stimulation to the stimulation of the right quadrants we observed large individual differences in our subject group. A possible morphological explanation is that the more elementary stimulation in the quadrants is connected with a greater number of dipole orientations as compared with the less elementary stimulation in the half-fields.