FIGURE 3.

Distance Profile. (A) Distances from one electrode to other electrodes form a particular pattern that could be utilized in identifying and labeling electrodes. (B) The distance profiles for six of the 64 electrodes of a subject (frontal: FP1 and FPZ, occipital: O1 and OZ, and central: CZ and M1). To construct the distance profile, we set the Euclidean distances between the electrode of interest and the rest of the 63 electrodes in a descending order. Comparing the distance profiles of FPZ and OZ the total distance of FPZ from all other electrodes would decrease slower than in the case of OZ. This profile is used to individualize the electrode for the assignment of labels to each electrode by comparison with electrodes with known position and label (Note: Distance values were extracted from the units available through Brainstorm from the MRI volumes).