A RAPID METHOD FOR DETERMINING STANDARD 10 10-ELECTRODE POSITIONS FORHIGH-RESOLUTION EEG STUDIES/

This report describes the basic principle and examines the comparative accuracy of a novel method for locating 3-D coordinates of electrode positions on the bead. The method involves calculation of the 3-D coor dinates for any array of 10/10 electrode positions from 14 straight-li ne distances between 11 10/10 electrodes. In 11 subjects the 3-D coord inates of 64 scalp electrodes embedded in an electrode cap were identi fied with the novel method, and also with a standard commercial magnet ic field digitizer. The outcomes from the two methods were compared wi th directly measured coordinates of all 64 positions (cf. De Munck, J. C., Vijn, P.C.M, and Spekreijse, PI. A practical method for determinin g electrode positions on the head. Electroenceph. clin. Neurophysiol., 1991, 89: 85-87). Coordinates in 3 dimensions obtained using the new method were significantly closer to the directly measured values than those from the magnetic field digitizer. The new method was also quick er and requires less specialized instrumentation than the magnetic fie ld digitization method. The novel method appears to be a valid and con venient tool for use with EEG analysis techniques that require specifi c information about 10/10 electrode positions. (C) 1998 Elsevier Scien ce Ireland Ltd. All rights reserved.