The use of an MEG device as a 3D digitizer and a motion correction system
نویسندگان
چکیده
An algorithm is described that localizes a set of simultaneously energized coils using MEG detectors. The algorithm is based on a mathematical model describing the coils as stationary magnetic dipoles, of which the source time functions are known. It is assumed that the source time functions are orthogonal. It is shown how this a priori knowledge can be used to improve the efficiency of the algorithm. The method is useful for continuous or intermittent head position registration during long MEG sessions, to registrate MR and MEG data, to localize EEG electrodes attached to the head, when EEG and MEG are recorded simultaneously, and to digitize the head shape. Experimental data shows that the localization error can be smaller than 2 mm.
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