Abstract: An improved method, termed “statistical synthetic aperture magnetometry” (SSAM) of transforming magnetoencephalographic (MEG) measurements into corresponding three-dimensional images of the electrophysiological activity within the brain. The computed images are static, representing the time-integrated brain activity over a selected period. By selecting the time periods and frequency bands of interest, the SSAM method selectively images brain activity relating to different types of brain pathology or to cognitive events. Unlike prior art methods, the SSAM method compensates for the growth of ionic signal source strength estimates with depth into the head, resulting, in part, from the declining sensitivity of the MEG sensors. This is achieved by computing and displaying functions of the ratio of source strength to its noise for each element comprising the image.
Abstract: A method of performing synthetic aperture magnetometery on the signals from a target organ using an array of biomagnetic sensors positioned in a predetermined manner around the target organ, each sensor in the array having a position vector and an orientation vector relative to a common coordinate system encompassing the target organ.